0001140361-24-012644 | 10-K | XBRL Viewer

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Income Taxes, Effective Income Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Effective income tax rate reconciliation [Abstract]
Statutory federal income tax benefit	$ 4,242	$ 3,048
State tax benefit, net of federal taxes	531	783
Foreign tax	(1)	(1)
Nondeductible/nontaxable items	(694)	548
Other	(295)	(41)
Valuation allowance (increase) decrease	(3,791)	(4,346)
Total income tax expense	$ (8)	$ (9)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Common Stock [Member] Series I Convertible Preferred Stock [Member]	Common Stock [Member] Series J Convertible Preferred Stock [Member]	Additional Paid in Capital [Member]	Additional Paid in Capital [Member] Series I Convertible Preferred Stock [Member]	Additional Paid in Capital [Member] Series J Convertible Preferred Stock [Member]	Accumulated Other Comprehensive Income [Member]	Accumulated Other Comprehensive Income [Member] Series I Convertible Preferred Stock [Member]	Accumulated Other Comprehensive Income [Member] Series J Convertible Preferred Stock [Member]	Accumulated Deficit [Member]	Accumulated Deficit [Member] Series I Convertible Preferred Stock [Member]	Accumulated Deficit [Member] Series J Convertible Preferred Stock [Member]	Total	Series I Convertible Preferred Stock [Member]	Series J Convertible Preferred Stock [Member]
Balance at Dec. 31, 2021	$ 0			$ 278,874			$ (35)			$ (252,892)			$ 25,947
Balance (in shares) at Dec. 31, 2021	105,376
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 0			0			0			(14,525)			(14,525)
Unrealized foreign currency translation adjustment	0			0			(7)			0			(7)
Unrealized gain on marketable securities	0			0			80			0			80
Stock-based compensation	$ 0			862			0			0			862
Stock-based compensation (in shares)	0
Issuance of common stock from ATM offering, net	$ 0			0			0			0			0
Issuance of common stock from ATM offering, net (in shares)	209,940
Issuance of common stock from conversion of convertible preferred stock	$ 0			0			0			0			0
Issuance of common stock from conversion of convertible preferred stock (in shares)	221,078
Balance at Dec. 31, 2022	$ 0			279,736			38			(267,417)			12,357
Balance (in shares) at Dec. 31, 2022	536,394
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ 0			0			0			(20,209)			(20,209)
Unrealized foreign currency translation adjustment	0			0			(13)			0			(13)
Unrealized gain on marketable securities	0			0			(56)			0			(56)
Stock-based compensation	$ 0			670			0			0			670
Stock-based compensation (in shares)	0
Issuance of common stock from ATM offering, net	$ 0			2,119			0			0			2,119
Issuance of common stock from ATM offering, net (in shares)	657,333
Issuance of common stock from conversion of convertible preferred stock		$ 0	$ 1		$ 0	$ 2,620		$ 0	$ 0		$ 0	$ 0		$ 0	$ 2,621
Issuance of common stock from conversion of convertible preferred stock (in shares)		10,493	3,417,079
Issuance costs related to 2022 common stock offering	$ 0			(11)			0			0			(11)
Issuance of common stock from exercise of warrants		$ 0			$ 307			$ 0			$ 0			$ 307
Issuance of common stock from warrant conversions (in shares)		1,061,162
Reclassification of warrants to equity	0			7,623			0			0			7,623
Series J Convertible Preferred Stock deemed dividend	0			(2,297)			0			0			(2,297)
Series J Convertible Preferred Stock PIK dividend	0			(121)			0			0			(121)
Balance at Dec. 31, 2023	$ 1			$ 290,646			$ (31)			$ (287,626)			$ 2,990
Balance (in shares) at Dec. 31, 2023	5,682,461

Operating Leases

12 Months Ended

Dec. 31, 2023

Operating Leases [Abstract]

Operating Leases

Note 8—Operating Leases

The Company leases a 23,000 square foot facility located in Eden Prairie, Minnesota for office and manufacturing space under a non-cancelable operating lease that expires in March 2027. In November 2021, the Company entered into a fourth amendment to the lease, extending the term of the lease from March 31, 2022, to March 31, 2027. This facility serves as our corporate headquarters and houses substantially all our functional areas. Monthly rent and common area maintenance charges, including estimated property tax for our headquarters, total approximately $34,000. The lease contains provisions for annual inflationary adjustments. Rent expense is being recorded on a straight-line basis over the term of the lease. Beginning on April 1, 2022, the annual base rent was $10.50 per square foot, subject to annual increases of $0.32 to $0.34 per square foot thereafter.

The cost components of the Company’s operating lease were as follows for the year ended December 31:

(in thousands)	2023		2022
Operating lease cost	$	249	$	238
Variable lease cost		142		127
Total	$	391	$	365

Variable lease costs consist primarily of taxes, insurance, and common area or other maintenance costs for our leased office and manufacturing space.

Maturities of our lease liability for the Company’s operating lease are as follows as of December 31:

(in thousands)	2023
2024	$	257
2025		264
2026		272
2027		69
Total lease payments		862
Less: Interest		(102	)
Present value of lease liability	$	760

As of December 31, 2023 and 2022, the remaining lease terms were 3.25 and 4.25 years, respectively, and discount rates were 6.25% and 6.25% respectively. For the years ended December 31, 2023, and 2022, the operating cash outflows from the Company’s operating lease for office and manufacturing space were $249,000 and $238,000, respectively.

Stock-Based Compensation, Stock Options (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 670,000	$ 862,000
Minimum [Member]
Additional Disclosures [Abstract]
Award vesting period	1 year
Maximum [Member]
Additional Disclosures [Abstract]
Award vesting period	4 years
Selling, General and Administrative [Member]
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 630,000	784,000
Research and Development [Member]
Stock-Based Compensation Expense Items [Abstract]
Stock-based compensation expense	$ 40,000	$ 78,000
Stock Options [Member]
Stock Options Activity [Roll Forward]
Outstanding, beginning balance (in shares)	10,485	7,481
Granted (in shares)	127,353	5,833
Exercised (in shares)	0	0
Forfeited/expired (in shares)	(26,922)	(2,829)
Outstanding, ending balance (in shares)	110,916	10,485
Vested at the end of the year (in shares)	8,882	3,531
Weighted Average Exercise Price [Abstract]
Outstanding, beginning balance (in dollars per share)	$ 404.08	$ 656.05
Granted (in dollars per share)	6.38	83.96
Exercised (in dollars per share)	0	0
Forfeited/expired (in dollars per share)	39.68	410.34
Outstanding, ending balance (in dollars per share)	35.9	404.08
Vested at the end of the year (in dollars per share)	$ 293.89	$ 727.26
Weighted Average Remaining Contractual Term [Abstract]
Options outstanding, weighted average remaining contractual life	9 years 2 months 4 days	9 years 2 months 4 days
Options vested, weighted average remaining contractual life	8 years 9 months 14 days	8 years 9 months 14 days
Aggregate Intrinsic Value [Abstract]
Fair value of options, vested	$ 614,100	$ 1,100,000
Weighted Average Assumptions used in Black-Scholes Option Pricing Model [Abstract]
Expected dividend yield	0.00%	0.00%
Risk-free interest rate	4.16%	2.13%
Expected volatility	152.28%	132.48%
Expected life	6 years 2 months 8 days	6 years 1 month 24 days
Additional Disclosures [Abstract]
Weighted-average fair value of options granted (in dollars per share)	$ 6.09	$ 76.05
Total unrecognized compensation costs related to non-vested stock option awards	$ 1,100,000
Unrecognized compensation costs related to non-vested stock option awards, recognition life	3 years 3 days

Income Taxes, Domestic and Foreign Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Domestic and foreign income (loss) before income taxes [Abstract]
Domestic	$ (20,233)	$ (14,551)
Foreign	32	35
Loss before income taxes	$ (20,201)	$ (14,516)

- Definition

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

+ References

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+ Details

Finance Lease Liability	12 Months Ended
Finance Lease Liability	Dec. 31, 2023
Finance Lease Liability [Abstract]
Finance Lease Liability	Note 9—Finance Lease Liability In 2020, the Company entered into lease agreements to finance equipment valued at $98,000. The equipment consisted of computer hardware and audio-visual equipment and is included in Property, Plant and Equipment in the accompanying consolidated financial statements. The principal amount under the lease agreements was $93,000 at the date the lease commenced, the implied interest rate is 7.5%, and the term of the lease is 39 months.

Related Party Transactions (Details) - USD ($)	12 Months Ended
Related Party Transactions (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Related Party Transactions [Abstract]
Amount of related party transactions	$ 0	$ 0

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2023

Stock-Based Compensation [Abstract]

Summary of Stock-Based Compensation Expense

The following table summarizes the stock-based compensation expense that was recognized in the consolidated statements of operations for the years ended December 31,

(in thousands)	2023		2022
Selling, general and administrative	$	630	$	784
Research and development		40		78
Total	$	670	$	862

Summary of Plan Stock Option Activity

The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2023					2022
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		10,485		$	404.08		7,481		$	656.05
Granted		127,353			6.38		5,833			83.96
Exercised		—			—		—			—
Forfeited/expired		(26,922	)		39.68		(2,829	)		410.34
Outstanding at December 31		110,916		$	35.90		10,485		$	404.08
Vested at December 31		8,882		$	293.89		3,531		$	727.26

Weighted Average Assumptions used in Black-Scholes Option Pricing Model

The following table provides the weighted average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2023			2022
Expected dividend yield		0	%		0	%
Risk-free interest rate		4.16	%		2.13	%
Expected volatility		152.28	%		132.48	%
Expected life (in years)		6.19			6.15

Revenue Recognition	12 Months Ended
Revenue Recognition	Dec. 31, 2023
Revenue Recognition [Abstract]
Revenue Recognition	Note 2 – Revenue Recognition Net Sales The Company sells its products in the United States primarily through a direct salesforce. Customers who purchase the Company’s products include hospitals and clinics throughout the United States. In countries outside the United States, the Company sells its products through a limited number of specialty healthcare distributors in Austria, Belarus, Brazil, Colombia, Czech Republic, Germany, Greece, Hong Kong, India, Indonesia, Israel, Italy, Panama, Romania, Singapore, Slovak Republic, Spain, Switzerland, Thailand, United Arab Emirates and the United Kingdom. These distributors resell the Company’s products to hospitals and clinics in their respective geographies. Revenue from product sales is recognized when the customer or distributor obtains control of the product, which occurs at a point in time, most frequently upon shipment of the product or receipt of the product, depending on shipment terms. The Company’s standard shipping terms are FOB shipping point unless the customer requests that control and title to the inventory transfer upon delivery. Revenue is measured as the amount of consideration we expect to receive, adjusted for any applicable estimates of variable consideration and other factors affecting the transaction price, which is based on the invoiced price, in exchange for transferring products. All revenue is recognized when the Company satisfies its performance obligations under the contract. The majority of the Company’s contracts have a single performance obligation and are short term in nature. The Company has entered into extended service plans with customers, which are recognized over time. This revenue represents less than 1% of net sales for each of the years ended December 31, 2023, and 2022. The unfulfilled performance obligations related to these extended service plans are included in deferred revenue, which is included in other current liabilities on the consolidated balance sheets. The majority of the deferred revenue is expected to be recognized within one year. Sales taxes and value added taxes in foreign jurisdictions that are collected from customers and remitted to governmental authorities are accounted for on a net basis and therefore are excluded from net sales. Revenue includes shipment and handling fees charged to customers. Shipping and handling costs associated with outbound freight after control over a product has transferred to a customer are accounted for as a fulfillment cost and are included in cost of goods sold. Product Returns: The Company offers customers a limited right of return for its product in case of non-conformity or performance issues. The Company estimates the amount of its product sales that may be returned by its customers and records this estimate as a reduction of revenue in the period the related product revenue is recognized. The Company currently estimates product return liabilities using available industry data and its own historical sales and returns information. The Company has received minimal returns to date and believes that future returns of its products will continue to be minimal. Therefore, revenue recognized is not currently impacted by variable consideration related to product returns.

- Definition

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

Fair Value of Financial Instruments, Available-for-Sale Marketable Securities Measured at Fair Value on Recurring Basis (Details) - Recurring [Member] - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Available-for-sale marketable securities [Abstract]
Marketable securities	$ 0	$ 569
Level 1 [Member]
Available-for-sale marketable securities [Abstract]
Marketable securities	$ 0	$ 569

Property, Plant and Equipment

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Note 3—Property, Plant and Equipment

Property, plant and equipment were as follows:

(in thousands)	December 31, 2023			December 31, 2022
Production Equipment	$	1,360		$	1,360
Loaners and Demo Equipment		1,534			1,444
Computer Software and Equipment		688			719
Office Furniture & Fixtures		375			375
Leasehold Improvements		253			253
Total		4,210			4,151
Accumulated Depreciation		(3,482	)		(3,171	)
	$	728		$	980

Depreciation and amortization expense was $362,000 and $372,000 for the years ended December 31, 2023, and 2022, respectively.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2023

Stock-Based Compensation [Abstract]

Stock-Based Compensation

Note 5— Stock-Based Compensation

Stock Options and Restricted Stock Awards

The Company has various share-based compensation plans, including the Third Amended and Restated 2017 Equity Incentive Plan, the 2013 Non-Employee Directors’ Equity Incentive Plan and the 2021 Inducement Plan (collectively, the “Plans”). The Plans are designed to assist in attracting, motivating, and retaining employees and directors and to recognize the importance of employees to the long-term performance and success of the Company. The Company has also granted stock options to certain non-employees outside of the Plans.

The Company recognized stock-based compensation expense related to grants of stock options and common stock awards to employees, directors and consultants of $670,000 and $862,000 during the years ended December 31, 2023 and 2022, respectively. The following table summarizes the stock-based compensation expense that was recognized in the consolidated statements of operations for the years ended December 31,

(in thousands)	2023		2022
Selling, general and administrative	$	630	$	784
Research and development		40		78
Total	$	670	$	862

The majority of the common stock awards and options to purchase common stock vest on the anniversary of the date of grant, which ranges from one to four years. Stock-based compensation expense related to these awards is recognized on a straight-line basis over the related vesting term in most cases, which generally is the service period. It is the Company’s policy to issue new shares upon the exercise of options.

Stock Options: The following is a summary of the Plans’ stock option activity during the years ended December 31:

	2023					2022
	Options Outstanding			Weighted Average Exercise Price		Options Outstanding			Weighted Average Exercise Price
Beginning Balance		10,485		$	404.08		7,481		$	656.05
Granted		127,353			6.38		5,833			83.96
Exercised		—			—		—			—
Forfeited/expired		(26,922	)		39.68		(2,829	)		410.34
Outstanding at December 31		110,916		$	35.90		10,485		$	404.08
Vested at December 31		8,882		$	293.89		3,531		$	727.26

For options outstanding and vested at December 31, 2023 and 2022, the weighted average remaining contractual life was 9.18 years and 8.79 years, respectively. There were no option exercises in 2023 or 2022. The total fair value of options that vested in 2023 and 2022 was $614,100, and $1.1 million, respectively, at the fair value of the options as of the date of grant.

Valuation Assumptions: The fair value of each stock option is estimated at the grant date using the Black-Scholes option pricing model. The fair value of stock options under the Black-Scholes option pricing model requires management to make assumptions regarding projected employee stock option exercise behaviors, risk-free interest rates, volatility of the Company’s stock price, and expected dividends.

The Company has not historically paid cash dividends to its common stockholders and currently does not anticipate paying any cash dividends in the foreseeable future. As a result, the Company has assumed a dividend yield of 0%. The risk-free interest rate is based upon the rates of U.S. Treasury bills with a term that approximates the expected life of the option. Since the Company has limited historical exercise data to reasonably estimate the expected life of its option awards, the expected life is calculated using a simplified method. Expected volatility is based on historical volatility of the Company’s stock.

The following table provides the weighted average assumptions used in the Black-Scholes option pricing model for the years ended December 31:

	2023			2022
Expected dividend yield		0	%		0	%
Risk-free interest rate		4.16	%		2.13	%
Expected volatility		152.28	%		132.48	%
Expected life (in years)		6.19			6.15

The weighted-average fair value of stock options granted in 2023 and 2022 was $6.09 and $76.05, respectively. As of December 31, 2023, the total compensation cost related to all non-vested stock option awards not yet recognized was approximately $1.1 million and is expected to be recognized over the remaining weighted-average life of 3.01 years.

Warrants: Warrants to purchase 2,963 and 679 shares of common stock were outstanding on December 31, 2023 and 2022, respectively. Exercisable warrants were 151,583 and 679,244 on December 31, 2023 and 2022, respectively. As of December 31, 2023, warrants outstanding were exercisable at prices ranging from $3.30 to $189,000 per share and are exercisable over a period ranging from immediately to 4.8 years.

Nature of Business and Significant Accounting Policies, Going Concern, Accounts Receivable and Inventories (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Customer	Dec. 31, 2022 USD ($) Customer
Going Concern [Abstract]
Accumulated deficit	$ (287,626)	$ (267,417)
Net proceeds from issuance of public offering	$ 40,900
Accounts Receivable [Abstract]
Accounts receivables maximum credit period from invoice date	30 days
Allowance for doubtful accounts	$ 0	0
Inventories [Abstract]
Finished Goods	393	993
Work in Process	207	204
Raw Materials	1,472	1,609
Inventory Reserve	(75)	(145)
Total	$ 1,997	$ 2,661
Accounts Receivable [Member]
Revenue, Performance Obligation [Abstract]
Number of major customers \| Customer	2	2
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage	14.00%	15.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage	15.00%	10.00%

Stock-Based Compensation, Warrants (Details) - Warrants [Member] - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Class of Warrant or Right [Abstract]
Warrants to purchase shares of common stock (in shares)	2,963,000	679,000
Exercisable warrants (in shares)	151,583	679,244
Minimum [Member]
Class of Warrant or Right [Abstract]
Exercise price of warrants (in dollars per share)	$ 3.3
Maximum [Member]
Class of Warrant or Right [Abstract]
Exercise price of warrants (in dollars per share)	$ 189,000
Warrants exercisable period	4 years 9 months 18 days

Commitments and Contingencies (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 27, 2022	Dec. 31, 2023	Dec. 31, 2022
Employee Retirement Plan [Abstract]
Employer's matching contribution		$ 268	$ 185
SeaStar Medical Holding Corporation [Member]
Commitments and Contingencies [Abstract]
Milestone payments	$ 450
Payment period after achievement of milestone event		30 days

Related Party Transactions	12 Months Ended
Related Party Transactions	Dec. 31, 2023
Related Party Transactions [Abstract]
Related Party Transactions	Note 11—Related Party Transactions There were no related party transactions requiring disclosure during the year ended December 31, 2023, and 2022.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-5

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-6

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 235
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481062/946-235-50-2

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(g)(3))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(c))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-07(2)(e))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483575/946-220-S99-1

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//850/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-6

Reference 12: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

Reference 13: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483326/850-10-50-1

+ Details

Finance Lease Liability (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2020
Finance Lease Liability [Abstract]
Value of finance lease equipment		$ 98,000
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]		Property, Plant and Equipment, Net
Principal amount under lease agreement		$ 93,000
Implied interest rate		7.50%
Finance lease term	39 months

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 3,800	$ 17,737
Marketable securities	0	569
Accounts receivable	1,951	1,406
Inventories, net	1,997	2,661
Other current assets	461	396
Total current assets	8,209	22,769
Property, plant and equipment, net	728	980
Operating lease right-of-use asset	713	903
Other assets	120	21
TOTAL ASSETS	9,770	24,673
Current liabilities
Accounts payable and accrued liabilities	2,380	2,245
Accrued compensation	525	2,161
Current portion of operating lease liability	216	196
Current portion of finance lease liability	0	28
Other current liabilities	51	58
Total current liabilities	3,172	4,688
Common stock warrant liability	2,843	6,868
Operating lease liability	544	760
Total liabilities	6,559	12,316
Commitments and contingencies
Mezzanine Equity
Series J Convertible Preferred Stock as of December 31, 2023 and December 31, 2022, par value $0.0001 per share; authorized 600,000 and none, issued and outstanding 11,950 and none, respectively	221	0
Stockholders' equity
Preferred stock	0	0
Common stock as of December 31, 2023 and December 31, 2022, par value $0.0001 per share; authorized 100,000,000 shares, issued and outstanding 5,682,461 and 536,394, respectively	1	0
Additional paid-in capital	290,646	279,736
Accumulated other comprehensive income:
Foreign currency translation adjustment	(31)	(18)
Unrealized gain (loss) on marketable securities	0	56
Accumulated deficit	(287,626)	(267,417)
Total stockholders' equity	2,990	12,357
TOTAL LIABILITIES, CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY	9,770	24,673
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity
Preferred stock	0	0
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock	0	0
Series I Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock	$ 0	$ 0

Insider Trading Arrangements	3 Months Ended
Insider Trading Arrangements	Dec. 31, 2023
Insider Trading Arrangements [Line Items]
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Operating Leases (Tables)

12 Months Ended

Dec. 31, 2023

Operating Leases [Abstract]

Cost Components of Operating Leases

The cost components of the Company’s operating lease were as follows for the year ended December 31:

(in thousands)	2023		2022
Operating lease cost	$	249	$	238
Variable lease cost		142		127
Total	$	391	$	365

Maturities of Lease Liability

Maturities of our lease liability for the Company’s operating lease are as follows as of December 31:

(in thousands)	2023
2024	$	257
2025		264
2026		272
2027		69
Total lease payments		862
Less: Interest		(102	)
Present value of lease liability	$	760

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Operating Activities
Net loss	$ (20,209)	$ (14,525)
Adjustments to reconcile net loss to cash flows from operating activities:
Depreciation and amortization	362	372
Stock-based compensation expense	670	862
Change in fair value of warrant liability	(758)	(11,827)
Financing expense	3,483	9,247
Net realized and unrealized gains on marketable securities	(65)	124
Changes in operating assets and liabilities:
Accounts receivable	(545)	(656)
Inventory	697	140
Other current assets	(65)	(68)
Other assets and liabilities	(7)	(96)
Accounts payable and accrued expenses	(1,500)	1,278
Net cash used in operating activities	(17,937)	(15,149)
Investing Activities:
Additions to intangible assets	(99)	0
Proceeds from sales of marketable securities	578	14,850
Purchase of property and equipment	(149)	(122)
Net cash provided by investing activities	330	14,728
Financing Activities:
Proceeds from public stock offerings, net	2,109	9,449
Proceeds from Series J Preferred Stock and Warrants	1,482	0
Proceeds from the exercise of warrants	120	0
Payments on finance lease liability	(28)	(26)
Net cash provided by financing activities	3,683	9,423
Effect of exchange rate changes on cash	(13)	(7)
Net decrease in cash and cash equivalents	(13,937)	8,995
Cash and cash equivalents - beginning of year	17,737	8,742
Cash and cash equivalents - end of year	3,800	17,737
Supplemental schedule of non-cash activities
Inventory transferred to property, plant and equipment	41	42
Issuance of Common Stock for exercise of Series I Warrants	7,623	0
Issuance of Series J Preferred Stock for exercise of Warrants	2,927	0
Deemed dividend on Series J Preferred Stock	2,297	0
Series J Preferred Stock issued for payment in kind dividend	121	0
Supplemental cash flow information
Cash paid for income taxes	$ 12	$ 9

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Consolidated Statements of Operations and Comprehensive Loss [Abstract]
Net sales	$ 8,864	$ 8,543
Cost of goods sold	3,881	3,788
Gross profit	4,983	4,755
Operating expenses:
Selling, general and administrative	17,191	17,584
Research and development	5,422	4,342
Total operating expenses	22,613	21,926
Loss from operations	(17,630)	(17,171)
Other income (expense), net
Other income	154	75
Financing expense	(3,483)	(9,247)
Change in fair value of warrant liability	758	11,827
Loss before income taxes	(20,201)	(14,516)
Income tax expense	(8)	(9)
Net loss	(20,209)	(14,525)
Deemed dividend attributable to Series J Convertible Preferred Stock	(2,297)	0
Dividend on Series J Convertible Preferred Stock	(121)	0
Net loss attributable to common stockholders	$ (22,627)	$ (14,525)
Basic loss per share (in dollars per share)	$ (11.52)	$ (83.55)
Diluted loss per share (in dollars per share)	$ (11.52)	$ (83.55)
Weighted average shares outstanding - basic (in shares)	1,964,406	173,846
Weighted average shares outstanding - diluted (in shares)	1,964,406	173,846
Other comprehensive loss:
Net loss	$ (20,209)	$ (14,525)
Unrealized (loss) gain on marketable securities	(56)	80
Unrealized foreign currency translation adjustment	(13)	(7)
Total comprehensive loss	$ (20,278)	$ (14,452)

Fair Value of Financial Instruments, Roll-Forward of Fair Value of Level 3 Warrants (Details) - Warrant [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Roll-Forward of Fair Value of Level 3 Warrants [Roll Forward]
Beginning balance	$ 6,868	$ 0
Ending balance	2,483	6,868
October 18, 2022 Series I Warrants Issuance [Member]
Roll-Forward of Fair Value of Level 3 Warrants [Roll Forward]
Issuance		18,695
Issuance of Common Stock for exercise of warrants	(7,623)
Change in fair value	755	$ (11,827)
October 17, 2023 Series J Warrants Issuance [Member]
Roll-Forward of Fair Value of Level 3 Warrants [Roll Forward]
Issuance	4,965
Exercise of warrants	(536)
Change in fair value	$ (1,586)

Property, Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2023

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, plant and equipment were as follows:

(in thousands)	December 31, 2023			December 31, 2022
Production Equipment	$	1,360		$	1,360
Loaners and Demo Equipment		1,534			1,444
Computer Software and Equipment		688			719
Office Furniture & Fixtures		375			375
Leasehold Improvements		253			253
Total		4,210			4,151
Accumulated Depreciation		(3,482	)		(3,171	)
	$	728		$	980

Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2023
Stockholders' Equity [Abstract]
Stockholders' Equity	Note 4—Stockholders’ Equity Series F Convertible Preferred Stock: On November 27, 2017, the Company closed on an underwritten public offering Series F Convertible Preferred Stock and warrants to purchase shares of common stock for gross proceeds of $18.0 million. Net proceeds totaled approximately $16.2 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The offering was comprised of Series F convertible preferred stock, convertible into shares of the Company’s common stock at a conversion price of $189,000 per share. Each share of Series F convertible preferred stock was accompanied by a Series 1 warrant, which was to expire on the first anniversary of its issuance, to purchase 16 shares of the Company’s common stock at an exercise price of $189,000 per share, and a Series 2 warrant, which expires on the seventh anniversary of its issuance, to purchase 4 shares of the Company’s common stock at an exercise price of $189,000 per share. The Series F convertible preferred stock has full ratchet price-based anti-dilution protection, subject to customary carve-outs, in the event of a down-round financing at a price per share below the conversion price of the Series F convertible preferred stock (which protection will expire if, during any 20 of 30 consecutive trading days, the volume weighted average price of the Company’s common stock exceeds 300% of the then-effective conversion price of the Series F convertible preferred stock and the daily dollar trading volume for each trading day during such period exceeds $200,000). The exercise price of the warrants is fixed and does not contain any variable pricing features, nor any price based anti-dilutive features, apart from customary adjustments for stock splits, combinations, reclassifications, stock dividends or fundamental transactions. A total of 18,000 shares of Series F convertible preferred stock convertible into 96 shares of common stock and warrants to purchase 191 shares of common stock were issued in the offering. Effective March 12, 2019, the conversion price of the Series F convertible preferred stock was reduced from $89,040 to $15,750, the per share price to the public of the Series G convertible preferred stock issued in the March 2019 Offering. Effective October 25, 2019, the conversion price of the Series F convertible preferred stock was reduced from $15,750 to $4,230, and on November 6, 2019, from $4,230 to $2,983, the per share price to the public in the October and November 2019 transactions, respectively. Effective January 28, 2020, the conversion price of the Series F convertible preferred stock was reduced from $2,983 to $1,650, the per share price to the public of the Series H convertible preferred stock which closed in an underwritten public offering on January 28, 2020, described below. Effective March 23, 2020, the conversion price of the Series F convertible preferred stock was reduced from $1,650 to $900, the per share price to the public in the March 2020 transaction, described below. In connection with the September 2021 offering, the conversion price of the Series F convertible preferred stock was reduced from $550 to $250, the per share price to the public in the September 2021 offering, described below. In connection with the October 2022 offering, the conversion price of the Series F convertible preferred stock was reduced from $250 to $25, the per share price to the public in the October 2020 offering, described below. In connection with the October 2023 offering, the conversion price of the Series F convertible preferred stock was reduced from $25 to $1.01, the per share price to the public in the October 2023 offering, described below. As of December 31, 2023 and December 31, 2022, 127 shares of the Series F convertible preferred stock remained outstanding. Market-Based Warrants: On May 30, 2019, the Company granted a market-based warrant to a consultant in exchange for investor relations services. The warrant represents the right to acquire up to 33 shares of the Company’s common stock at an exercise price of $9,540 per share, the closing stock price of the Company’s common shares on May 30, 2019. The warrant is subject to a vesting schedule based on the Company achieving certain market stock prices within a specified period of time. The warrant expires on May 30, 2024. None of these warrants had vested as of December 31, 2023. Series H Convertible Preferred Stock and January 2020 Offering: On January 28, 2020, the Company closed on an underwritten public offering of common stock, Series H convertible preferred stock, and warrants to purchase shares of common stock for gross proceeds of $9.7 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants (“January 2020 Offering”). Net proceeds totaled approximately $8.6 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The Series H convertible preferred stock included a beneficial conversion amount of $1.6 million, representing the intrinsic value of the shares at the time of issuance, and $0.2 million of down-round protection in connection with the re-pricing of the warrants following the March 2020 offering described below. The January 2020 Offering was comprised of 2,015 shares of common stock priced at $1,650 per share and 115,173 shares of Series H convertible preferred stock, convertible into common stock at $1,650 per share, including the full exercise of the over-allotment option. Each share of Series H convertible preferred stock and each share of common stock was accompanied by a warrant to purchase common stock. The warrants are exercisable into 5,855 shares of common stock. The conversion price of the preferred stock issued in the transaction is fixed and does not contain any variable pricing feature or any price-based anti-dilutive feature. The preferred stock issued in this transaction includes a beneficial ownership blocker but has no dividend rights (except to the extent that dividends are also paid on the common stock) or liquidation preference, and, subject to limited exceptions, has no voting rights. The securities comprising the units are immediately separable and were issued separately. The warrants were exercisable beginning on the closing date and expire on the fifth anniversary of the closing date and had an initial exercise price per share equal to $1,650 per share, subject to appropriate adjustment in the event of subsequent equity sales of common stock or securities convertible into common stock for an exercise price per share less than the exercise price per share of the warrants then in effect (but in no event lower than 10% of the applicable unit offering price), or in the event of recapitalization events, stock dividends, stock splits, stock combinations, reclassifications, reorganizations or similar events affecting our common stock. Effective March 23, 2020, the exercise price of these warrants was reduced from $1,650 to $900, the per share price to the public in the March 2020 offering, described below. As of December 31, 2023 and 2022, there were 6,532 warrants outstanding. March 2020 Offering: On March 23, 2020, the Company closed on a registered direct offering of 1,387 shares of its common stock at a price to the public of $900 per share, for gross proceeds of approximately $1.2 million, or $1.0 million net proceeds, after deducting commissions and offering expenses. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 1,387 shares of the Company’s common stock. The warrants to purchase up to 1,387 shares of common stock have an exercise price of $1,118 per share, were exercisable six months from the date of issuance, and will expire five and a half years from the date of issuance. April 2020 Offering: On April 1, 2020, the Company closed on a registered direct offering of 1,710 shares of its common stock at a price to the public of $1,302 per share, for gross proceeds of approximately $2.2 million, prior to deduction of commissions and offering expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 855 shares of the Company’s common stock. The warrants have an exercise price of $1,115 per share, were exercisable immediately, and will expire five and a half years from the date of issuance. May 2020 Offering: On May 5, 2020, the Company closed on a registered direct offering of 1,199 shares of its common stock at a price to the public of $1,418 per share, for gross proceeds of approximately $1.7 million, prior to deduction of commissions and offering expenses related to the transaction. In a concurrent private placement, the Company agreed to issue to the investors in the registered direct offering warrants to purchase up to 600 shares of the Company’s common stock. The warrants have an exercise price of $1,230 per share, were exercisable immediately, and will expire five and a half years from the date of issuance. August 2020 Offering: On August 21, 2020, the Company closed on an underwritten public offering of common stock and warrants to purchase shares of common stock for gross proceeds of approximately $14.4 million, which included the full exercise of the underwriter’s over-allotment option to purchase additional shares and warrants (“August 2020 Offering”). Net proceeds totaled approximately $13.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering. The August 2020 Offering was comprised of 10,647 shares of common stock priced at $1,350 per share. Each share of common stock was accompanied by a warrant to purchase common stock. The warrants are exercisable into 10,647 shares of common stock. The securities comprising the units are immediately separable and were issued separately. The warrants were exercisable beginning on the effective date of our stockholders’ approval of a reverse stock split in an amount sufficient to permit the exercise in full of the warrants, which occurred on October 6, 2020, and will expire on the five-year anniversary of the closing date. March 2021 Offering: On March 19, 2021, the Company closed on an underwritten public offering of 37,958 shares of common stock, for gross proceeds of approximately $20.9 million (the “March 2021 Offering”). Net proceeds totaled approximately $18.9 million after deducting the underwriting discounts and commissions and other costs associated with the offering and after giving effect to the underwriters’ full exercise of their overallotment option. In connection with the March 2021 Offering, the conversion price of the Series F convertible preferred stock was reduced from $900 to $550, the per share price to the public in the March 2021 Offering. In addition, the exercise price of the common stock warrants issued in connection with the January 2020 Offering was reduced from $900 to $550, the per share price to the public in the March 2021 Offering. September 2021 Offering: On September 17, 2021, the Company closed on an underwritten public offering of 40,056 shares of common stock, for gross proceeds of approximately $10.0 million (the “September 2021 Offering”). Net proceeds totaled approximately $9.0 million after deducting the underwriting discounts and commissions and other costs associated with the offering and after giving effect to the underwriters’ full exercise of their overallotment option. In connection with the September 2021 Offering, the conversion price of the Series F convertible preferred stock was reduced from $550 to $250, the per share price to the public in the September 2021 Offering. In addition, the exercise price of the common stock warrants issued in connection with the January 2020 Offering was reduced from $550 to $250, the per share price to the public in the September 2021 Offering. October 2022 Offering: On October 18, 2022, the Company closed on an underwritten public offering of 209,940 shares of common stock and 23,157,124 shares of Series I convertible preferred stock, for gross proceeds of approximately $11.0 million (the “October 2022 Offering”). Net proceeds totaled approximately $9.4 million after deducting underwriting discounts and commissions and other costs associated with the offering and after giving effect to the underwriters’ full exercise of their overallotment option. The offering was comprised of (1) 209,940 Class A Units, priced at a public offering price of $25 per Class A Unit, with each Class A Unit consisting of one share of common stock and 1.5 warrants to purchase one share of common stock at an exercise price of $25 per share, and (2) 23,157,124 Class B Units, priced at a public offering price of $0.25 per Class B Unit, with each Class B Unit consisting of one share of Series I convertible preferred stock, convertible into one share of common stock for every one hundred shares of Series I convertible preferred stock, and 1.5 warrants to purchase one share of common stock for every one hundred shares of Series I convertible preferred stock The warrants included a cashless exercise provision that upon becoming exercisable, the warrant holders could exercise at a $0.00 exercise price. The warrants became exercisable beginning on the effective date of a reverse stock split in an amount sufficient to permit the exercise in full of the warrants, contingent upon stockholder approval of such reverse stock split and of the exercisability of the warrants under Nasdaq rules and will expire on the sixth anniversary of the initial exercise date. The warrants were reflected as a liability and were valued on day 1. The valuation exceeded the gross proceeds of the offering, which resulted in a day 1 financing expense of $7.7 million. The warrants were re-measured at fair value as of December 31, 2022, with the fair value change being recorded as non-operating income. On December 8, 2022, following a special meeting of stockholders, the Company’s board of directors approved a one-for-one hundred reverse stock split of the Company’s issued and outstanding shares of common stock. On December 9, 2022, the Company filed with the Secretary of State of the State of Delaware a Certificate of Amendment to its Certificate of Incorporation to effect the Reverse Stock Split. The Reverse Stock Split became effective as of 5:00 p.m. Eastern Time on December 9, 2022, and the Company’s common stock began trading on a split-adjusted basis when the market opened on December 12, 2022. The conversion price of the preferred stock issued in the transaction was fixed and does not contain any variable pricing feature or any price-based anti-dilutive feature. The preferred stock issued in this transaction includes a beneficial ownership blocker but has no dividend rights (except to the extent that dividends are also paid on the common stock) or liquidation preference and, subject to limited exceptions, has no voting rights. The securities comprising the units are immediately separable and were issued separately. In connection with the October 2022 Offering, the conversion price of the Series F convertible preferred stock was reduced from $250 to $25, the per share price to the public in the October 2022 Offering. In addition, the exercise price of the common stock warrants issued in connection with the January 2020 Offering was reduced from $250 to $25, the per share price to the public in the October 2022 Offering. In connection with the October 2023 offering, the conversion price of the Series F convertible preferred stock was reduced from $25 to $1.01, the per share price to the public in the October 2023 offering, described below. Reverse Stock Split: On December 5, 2022, the Company’s stockholders approved a reverse split of its outstanding common stock at a ratio in the range of 1-for-50 to 1-for-100 and, on December 8, 2022, the Company’s board of directors approved a 1-for-100 reverse split of the Company’s outstanding common stock that became effective after trading on December 9, 2022. This reverse stock split did not change the par value of the Company’s common stock or the number of common or preferred shares authorized by the Company’s Fourth Amended and Restated Certificate of Incorporation, as amended. All share and per-share amounts have been retroactively adjusted to reflect the reverse stock splits for all periods presented. 2023 At-the-Market Program: In March 2023, the Company filed a Prospectus Supplement to its Registration Statement on Form S-3 with the SEC in connection with a proposed At-the-Market Securities offering (the “At-the-Market Program”). During 2023, the Company issued 657,333 shares of common stock under the At-the-Market Program for gross proceeds of approximately $2.3 million. Net proceeds totaled approximately $2.1 million after deducting the underwriting discounts and commissions and other costs associated with the offering. Supply Agreement Warrants: On June 19, 2023, we entered into a Supply and Collaboration Agreement with DaVita Inc., a Delaware corporation, pursuant to which DaVita will pilot the Aquadex ultrafiltration therapy system to treat adult patients with congestive heart failure and related conditions within select U.S. markets. The pilot program launched in the third quarter 2023 and will extend through May 31, 2024. Through the Pilot, ultrafiltration therapy using Aquadex will be offered at a combination of DaVita’s hospital customer and outpatient center locations, with both companies collaborating on the roll-out of the therapy, clinician training, and patient support. At the conclusion of the Pilot, DaVita has the option, in its sole discretion, to extend the Supply Agreement with the Company for continued provision of both inpatient and outpatient ultrafiltration services for up to 10 years. October 2023 Offering: On October 12, 2023, Nuwellis, Inc. entered into a Placement Agency Agreement with Lake Street Capital Markets, LLC and Maxim Group LLC, pursuant to which the Company issued and sold, in a best efforts registered public offering by the Company, 150,000 units, with each Unit consisting of (A) one share of the Company’s Series J Convertible Redeemable Preferred Stock, par value $0.0001 per share, and (B) one warrant to purchase one-half of one (0.50) share of Series J Convertible Preferred Stock, at a price to the public of $15.00 per Unit, less placement agent fees and commissions. The public offering price of $15.00 per Unit reflects the issuance of the Series J Convertible Preferred Stock with an original issue discount of 40%. The Company is also registering under the Registration Statement (as defined below) an additional 362,933 shares of Series J Convertible Preferred Stock that will be issued, if and when the Company’s Board of Directors declares such dividends, as paid in-kind dividends and the shares of Common Stock issuable upon conversion of the Series J Convertible Preferred Stock issued as PIK dividends. The Units, the shares of Series J Convertible Preferred Stock, the Warrants, the PIK Dividend Shares, the PIK Conversion Shares as well as the shares of Series J Convertible Preferred Stock issuable upon exercise of the Warrants and the shares of the Company’s common stock, par value $0.0001 per share, issuable upon conversion of the Series J Convertible Preferred Stock, were offered and sold by the Company pursuant to an effective registration statement on Form S-1, as amended (File No. 333-274610), which was initially filed with the Securities Exchange Commission on September 21, 2023, as amended on September 29, 2023, and declared effective by the SEC on September 29, 2023 with an additional registration statement on Form S-1 filed on October 6, 2023 pursuant to Rule 462(c). A final prospectus relating to the Offering was filed with the SEC on October 13, 2023. The closing of the Offering contemplated by the Placement Agency Agreement occurred on October 17, 2023. On October 17, 2023, the Company also entered into a warrant agency agreement with the Company’s transfer agent, Equiniti Trust Company, LLC, who will act as warrant agent for the Company, setting forth the terms and conditions of the Warrants sold in this Offering. Each Warrant has an exercise price of $7.50 per one-half of one (0.5) share of Series J Convertible Preferred Stock, is immediately exercisable and will expire three (3) years from the date of issuance. There is no established trading market for the Series J Convertible Preferred Stock or the Warrants and we do not expect a market to develop. In addition, we do not intend to list the Series J Convertible Preferred Stock or the Warrants on The Nasdaq Capital Market or any other national securities exchange or any other nationally recognized trading system. The gross proceeds to the Company from the October 17, 2023, Offering were $2.25 million. Net proceeds were approximately $1.5 million after deducting placement agent fees and commissions and Offering expenses payable by the Company. The Company used the net proceeds from the Offering for working capital and for general corporate purposes. The Series J Convertible Preferred Stock is classified as mezzanine equity and accreted to reflect its redemption value as of each reporting date. The accretion will be reflected as a deemed dividend adjustment to arrive at net loss attributed to common stockholders for earnings per share calculations. The warrants are recorded as a liability and re-measured at fair value as of each reporting date with fair value changes being recorded as non-operating income or expense. The warrants were valued on day 1 and exceeded the gross proceeds of the offering. This resulted in a day 1 financing expense of $2.7 million. Underwriter and Placement Agent Fees: In connection with the offerings described above, the Company paid the underwriter or placement agent, as applicable, an aggregate cash fee equal to 8% of the aggregate gross proceeds raised in each of the offerings, except with respect to the issuances made pursuant to the At-the-Market Program, for which the placement fee was equal to 3% of the aggregate gross proceeds. In conjunction with the Supply Agreement, the Company issued DaVita a warrant to purchase up to an aggregate of 1,289,081 shares of common stock of the Company, par value $0.0001 per share, at an exercise price of $3.2996 per share, provided that at no time can the DaVita Warrant be exercised for an amount of shares that would represent greater than 19.9% ownership in the Company subject to certain vesting milestones. The DaVita Warrant is expected to vest in four tranches as follows: (i) 25% upon receipt of notice to extend the Supply Agreement past the initial pilot-term; (ii) 25% upon the attainment by the Company of a net revenue achievement from DaVita’s efforts pursuant to the Supply Agreement within twelve months of Ultrafiltration Services Approval; (iii) 25% upon the attainment by the Company of a net revenue achievement from DaVita’s efforts pursuant to the Supply Agreement within twenty-four months of Ultrafiltration Services Approval; and (iv) 25% upon the attainment by the Company of a net revenue achievement from DaVita’s efforts pursuant to the Supply Agreement within thirty-six months of Ultrafiltration Services Approval. This warrant had not vested as of December 31, 2023. The Company evaluated the accounting treatment for the DaVita Warrant pursuant to ASC 718, “Stock Compensation,” and ASC 480, “Distinguishing Liabilities from Equity,” and concluded that the DaVita Warrant should be classified as an equity instrument on the balance sheet as of December 31, 2023. In accordance with this treatment, the Company’s management concluded none of the performance-based vesting conditions of the DaVita Warrant were probable of vesting as of December 31, 2023, and therefore, no expense associated with the DaVita Warrant was recognized in the Company’s financial statements as of that date. The Company will continue to evaluate the probability of achieving the performance milestones associated with the DaVita Supply Agreement and will record the related equity-based expense in its financial statements based on the grant date fair value of the DaVita Warrant when management deems it is probable that the performance-based vesting conditions will be achieved.

- Definition

The entire disclosure for equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Name Accounting Standards Codification
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-Paragraph 13
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 6: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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Reference 9: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
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Reference 10: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI https://asc.fasb.org//505/tableOfContent

Reference 11: http://www.xbrl.org/2003/role/disclosureRef
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Reference 12: http://www.xbrl.org/2003/role/disclosureRef
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Reference 13: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 13
-Subparagraph (i)
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-13

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
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-Paragraph 14
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Reference 15: http://www.xbrl.org/2003/role/disclosureRef
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Reference 16: http://www.xbrl.org/2003/role/disclosureRef
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Reference 17: http://www.xbrl.org/2003/role/disclosureRef
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Reference 18: http://www.xbrl.org/2003/role/disclosureRef
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Reference 19: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://asc.fasb.org//1943274/2147481112/505-10-50-18

+ Details

Nature of Business and Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2023

Nature of Business and Significant Accounting Policies [Abstract]

Going Concern

The Company’s financial statements have been prepared and presented on a basis assuming it continues as a going concern. During the years ended December 31, 2023 and 2022, the Company incurred losses from operations and net cash outflows from operating activities as disclosed in the consolidated statements of operations and cash flows, respectively. As of December 31, 2023, the Company had an accumulated deficit of $287.6 million, and it expects to incur losses for the immediate future. To date, the Company has been funded by equity financings, and although the Company believes that it will be able to successfully fund its operations, there can be no assurance that it will be able to do so or that it will ever operate profitably. These factors raise substantial doubt about the Company’s ability to continue as a going concern through at least twelve months from the report date.

The Company became a revenue-generating company after acquiring the Aquadex Business in August 2016. The Company expects to incur additional losses in the near-term as it grows the Aquadex Business, including investments in expanding its sales and marketing capabilities, purchasing inventory, manufacturing components, investing in clinical research and new product development, and complying with the requirements related to being a U.S. public company. To become and remain profitable, the Company must succeed in expanding the adoption and market acceptance of the Aquadex System. This will require the Company to succeed in training personnel at hospitals and effectively and efficiently manufacturing, marketing, and distributing the Aquadex System and related components. There can be no assurance that the Company will succeed in these activities, and it may never generate revenues sufficient to achieve profitability.

During 2021 and through December 31, 2023, the Company closed on underwritten public equity offerings for aggregate net proceeds of approximately $40.9 million after deducting the underwriting discounts and commissions and other costs associated with the offerings. See Note 4—Stockholders’ Equity for additional related disclosure. The Company will require additional funding to grow its Aquadex Business, which may not be available on terms favorable to the Company, or at all. The Company may receive those funds from the proceeds from future warrant exercises, issuances of equity securities, or other financing transactions.

The Company believes that its existing capital resources will be sufficient to support its operating plan through May 31, 2024. However, the Company will seek to raise additional capital to support its growth or other strategic initiatives through debt, equity, or a combination thereof. There can be no assurance we will be successful in raising additional capital.

Segment Information

Operating segments are defined as components of an enterprise about which separate discrete information is available for evaluation by the chief operating decision-maker in deciding how to allocate resources and assess performance. The Company and the Company’s chief operating decision-maker, the Company’s chief executive officer, views the Company’s operations and manages its business as a single operating segment. At December 31, 2023 and 2022, long-lived assets were located primarily in the United States.

Basis of Presentation

The accompanying consolidated financial statements include the accounts of Nuwellis, Inc. and its wholly owned subsidiary, Sunshine Heart Ireland Limited. All intercompany accounts and transactions between consolidated entities have been eliminated.

Use of Estimates

The preparation of financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts and disclosures in the consolidated financial statements and accompanying notes. Actual results could differ materially from those estimates.

Cash and Cash Equivalents

Cash and cash equivalents consist of cash and term deposits with original maturities of three months or less. The carrying value of these instruments approximates fair value. The balances, at times, may exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents.

Marketable securities

The Company’s marketable securities typically consist of investment-grade, U.S. dollar-denominated fixed and floating-rate debt, which are classified as available-for-sale and included in current assets. Most marketable securities mature within twelve months from their date of purchase and generally are intended to fund current operations. Securities are valued based on market prices for similar assets using third party certified pricing sources. Available-for-sale securities are carried at fair value with unrealized gains and losses reported as a component of shareholders’ equity in accumulated other comprehensive income (loss).

Available-for-sale securities are reviewed for possible impairment at least quarterly, or more frequently if circumstances arise that may indicate impairment. When the fair value of the securities declines below the amortized cost basis and impairment is indicated, it must be determined whether the impairment is other than temporary. Impairment is considered to be other than temporary if the Company: (i) intends to sell the security, (ii) will more likely than not be forced to sell the security before recovering its cost, or (iii) does not expect to recover the security’s amortized cost basis. If the decline in fair value is considered other than temporary, the cost basis of the security is adjusted to its fair market value and the realized loss is reported in earnings. Subsequent increases or decreases in fair value are reported as a component of shareholders’ equity in accumulated other comprehensive gain (loss).

Accounts Receivable

Accounts receivables are unsecured, recorded at net realizable value, and do not bear interest. The Company makes judgments as to its ability to collect outstanding receivables based upon significant patterns of collectability, historical experience, and management’s evaluation of specific accounts, and it will provide an allowance for credit losses when collection becomes doubtful. The Company performs credit evaluations of its customers’ financial condition on an as-needed basis. Payment is generally due 30 days from the invoice date and accounts past 30 days are individually analyzed for collectability. When all collection efforts have been exhausted, the account is written off against the related allowance. To date the Company has not experienced any write-offs or significant deterioration in the aging of its accounts receivable, and therefore, no allowance for doubtful accounts was considered necessary as of December 31, 2023, or December 31, 2022. As of December 31, 2023, two customers represented 14% and 15% of the total accounts receivable balance. As of December 31, 2022, two customers represented 15% and 10% of the total accounts receivable balance.

Inventories

Inventories are recorded at the lower of cost or net realizable value using the first-in, first-out method. Overhead is allocated to manufactured finished goods inventory based on the normal capacity of the Company’s production facilities. Abnormal amounts of overhead, if any, are expensed as incurred. On a regular basis, the Company reviews its inventory and identifies that which is excess, slow moving, and obsolete by considering factors such as inventory levels and expected product life. A reserve is established for any identified excess, slow moving, and obsolete inventory through a charge to cost of goods sold. Inventories consisted of the following as of December 31:

(in thousands)	2023			2022
Finished Goods	$	393		$	993
Work in Process		207			204
Raw Materials		1,472			1,609
Inventory Reserve		(75	)		(145	)
Total	$	1,997		$	2,661

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Property, plant and equipment is stated at cost less accumulated depreciation. Depreciation is computed based upon the estimated useful life of the respective asset. Leasehold improvements are amortized using the straight-line method over the shorter of the lease term or the estimated useful life of the assets. Repairs and maintenance cost is expensed as incurred. The cost and accumulated depreciation of property, plant and equipment retired or otherwise disposed of is removed from the related accounts, and any residual values are charged to expense. Depreciation expense has been calculated using the following estimated useful lives:

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Depreciation and amortization expense was $362,000 and $372,000 for the years ended December 31, 2023, and 2022, respectively.

Property, plant and equipment is reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset or asset group may not be recoverable. If the impairment tests indicate that the carrying value of the asset or asset group is greater than the expected undiscounted cash flows to be generated by such asset or asset group, further analysis is performed to determine the fair value of the asset or asset group. To the extent the fair value of the asset or asset group is less than its carrying value, an impairment loss is recognized equal to the amount the fair value of the asset or asset group is exceeded by its carrying amount. Assets to be disposed of are carried at the lower of their carrying value or fair value less costs to sell. Considerable management judgment is necessary to estimate the fair value of assets or asset groups, and accordingly, actual results could vary significantly from such estimates.

The Company continues to report operating losses and negative cash flows from operations, both of which it considers to be indicators of potential impairment. Therefore, the Company evaluates its long-lived assets for potential impairment at each reporting period. The Company has concluded that its cash flows from the various long-lived assets are highly interrelated and, as a result, the Company consists of a single asset group. As the Company expects to continue incurring losses in the foreseeable future, the undiscounted cash flow step was bypassed, and the Company proceeded to fair value the asset group. The Company has determined the fair value of the asset group using its market capitalization determined with level 1 fair value inputs. For the operating lease right-of-use asset the Company believes that the remaining lease payments represent a fair value of the right of use asset.

There have been no impairment losses recognized for the years ended December 31, 2023, or 2022.

Revenue Recognition

The Company recognizes revenue in accordance with Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contracts with Customers. Accordingly, the Company recognizes revenue when its customers obtain control of its products or services, in an amount that reflects the consideration that the Company expects to receive in exchange for those goods and services. See Note 2 – Revenue Recognition, for additional disclosures. For the year ended December 31, 2023, two customers represented 13.9% and 12.6% of net sales. For the year ended December 31, 2022, one customer represented 12.5% of net sales.

Foreign Currency Translation

Sales and expenses denominated in foreign currencies are translated at average exchange rates in effect throughout the year. Assets and liabilities of foreign operations are translated at period-end exchange rates with the impacts of foreign currency translation recorded in cumulative translation adjustment, a component of accumulated other comprehensive income. Foreign currency transactions gains and losses are included in other expense, net in the consolidated statements of operations and other comprehensive loss.

Stock-Based Compensation

The Company recognizes all share-based payments to employees, directors, and consultants, including grants of stock options and common stock awards, in the consolidated statement of operations and comprehensive loss as an operating expense based on their fair values as established at the grant date. Equity instruments issued to non-employees include common stock awards or warrants to purchase shares of our common stock. These common stock awards or warrants are either fully vested and exercisable at the date of grant or vest over a certain period during which services are provided. The Company expenses the fair market value of fully vested awards at the time of grant, and of unvested awards over the period in which the related services are received.

The Company computes the estimated fair values of stock options using the Black-Scholes option pricing model. Market price at the date of grant is used to calculate the fair value of common stock awards.

Stock-based compensation expense is recorded based on awards ultimately expected to vest and is reduced for forfeitures. See Note 5—Stock-Based Compensation, for further information regarding the assumptions used to calculate the fair value of stock-based compensation.

Income Taxes

Deferred income taxes are provided on a liability method, whereby deferred tax assets are recognized for deductible temporary differences and operating loss and tax credit carryforwards. Deferred tax liabilities are recognized for taxable temporary differences, which are the differences between the reported amounts of assets and liabilities and their tax bases. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Deferred tax assets and liabilities are adjusted for the effects of changes in tax laws and rates on the date of enactment. The Company recognizes the financial statement benefit of a tax position only after determining that the relevant tax authority would more likely than not sustain the position following an audit. For tax positions meeting the more-likely-than-not threshold, the amount recognized in the consolidated financial statements is the largest benefit that has a greater than 50 percent likelihood of being realized upon ultimate settlement with the relevant tax authority.

Loss per Share

Basic loss per share is computed based on the net loss for each period divided by the weighted average number of common shares outstanding. The net loss allocable to common stockholders for the year ended December 31, 2023, includes a deemed dividend from the Series J Convertible Preferred Stock of $2.3 million and a payment in kind dividend from the Series J Convertible Preferred Stock of $0.1 million. (see Note 4 — Stockholders’ Equity).

Diluted earnings per share is computed based on the net loss allocable to common stockholders for each period divided by the weighted average number of common shares outstanding, increased by the number of additional shares that would have been outstanding had the potentially dilutive common shares been issued, and reduced by the number of shares the Company could have repurchased from the proceeds from issuance of the potentially dilutive shares. Potentially dilutive shares of common stock include shares underlying outstanding convertible preferred stock, warrants, stock options and other stock-based awards granted under stock-based compensation plans.

The following table sets forth the potential shares of common stock that are not included in the calculation of diluted net loss per share because to do so would be anti-dilutive as of the end of each year presented:

	December 31,
	2023		2022
Stock options		110,916		10,485
Warrants to purchase common stock		2,963,192		679,244
Series F convertible preferred stock		125,857		5,080
Series I convertible preferred stock		—		10,493
Series J convertible preferred stock		295,792		—
Total		3,495,757		705,302

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2023			2022
Net loss to common stockholders	$	(20,209	)	$	(14,525	)
Deemed dividend attributable to Series J Convertible Preferred Stock		(2,297	)		—
Dividend on Series J Convertible Preferred Stock		(121	)		—
Net loss after deemed dividend		(22,627	)		(14,525	)
Weighted average shares outstanding		1,964			174
Basic and diluted loss per share	$	(11.52	)	$	(83.55	)

Research and Development

Research and development (R&D) costs include activities related to development, design, and testing improvements of the Aquadex System and potential related new products. These R&D costs also include expenses related to clinical research that the Company may sponsor or conduct to enhance understanding of the product and its use. R&D costs are expensed as incurred.

Recent Accounting Pronouncements

In June 2016, the FASB issued Accounting Standards Update (ASU) 2016-13, “Financial Instruments – Credit Losses.” This ASU added a new impairment model (known as the current expected credit loss (“CECL”) model) that is based on expected losses rather than incurred losses. Under the new guidance, an entity recognizes as an allowance its estimate of expected credit losses. The CECL model applies to most debt instruments, trade receivables, lease receivables, financial guarantee contracts, and other loan commitments. The CECL model does not have a minimum threshold for recognition of impairment losses, and entities will need to measure expected credit losses on assets that have a low risk of loss. As a smaller reporting company pursuant to Rule 12b-2 of the Securities Exchange Act of 1934, as amended, these changes become effective for the Company on January 1, 2023. The Company has adopted the new standard effective January 1, 2023, which didn’t have a material impact on the consolidated financial statements.

The Company evaluates subsequent events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements.

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2023

Income Taxes [Abstract]

Domestic and Foreign Income (Loss) Before Income Taxes

Domestic and foreign income (loss) before income taxes consists of the following for the years ended December 31:

(in thousands)	2023			2022
Domestic	$	(20,233	)	$	(14,551	)
Foreign		32			35
Loss before income taxes	$	(20,201	)	$	(14,516	)

Components of Income Tax Expense

The components of income tax expense consist of the following for the years ended December 31:

(in thousands)	2023			2022
Current:
United States and state	$	—		$	—
Foreign, net		(8	)		(9	)
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax expense	$	(8	)	$	(9	)

Actual Income Tax Expense Differs from Statutory Federal Income Tax Expense

Actual income tax expense differs from statutory federal income tax expense as follows for the years ended December 31:

(in thousands)	2023			2022
Statutory federal income tax benefit	$	4,242		$	3,048
State tax benefit, net of federal taxes		531			783
Foreign tax		(1	)		(1	)
Nondeductible/nontaxable items		(694	)		548
Other		(295	)		(41	)
Valuation allowance (increase) decrease		(3,791	)		(4,346	)
Total income tax expense	$	(8	)	$	(9	)

Deferred Taxes

Deferred taxes consist of the following as of December 31:

(in thousands)	2023			2022
Deferred tax assets:
Noncurrent:
Accrued leave	$	25		$	397
Stock based compensation		285			360
Net operating loss carryforward		48,818			45,405
Other		26			42
Intangibles		2,627			1,786
R&D credit carryforward		531			531
Total deferred tax assets		52,312			48,521
Less: valuation allowance		(52,312	)		(48,521	)
Total	$	—		$	—

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2023
Commitments and Contingencies [Abstract]
Commitments and Contingencies	Note 10—Commitments and Contingencies Employee Retirement Plan The Company has a 401(k) plan that provides a retirement benefit to substantially all full-time U.S. employees. Eligible employees may contribute a percentage of their annual compensation, subject to Internal Revenue Service limitations, with the Company matching a portion of the employees’ contributions at the discretion of the Company. Matching contributions totaled $268,000 and $185,000 for the years ended December 31, 2023, and 2022, respectively. Milestone Payment On December 27, 2022, the Company entered into a license and distribution agreement with SeaStar Medical Holding Corporation, (Nasdaq: ICU), a medical device company developing proprietary solutions to reduce the consequences of dysregulated immune responses including hyperinflammation on vital organs (“SeaStar”), appointing the Company as the exclusive U.S. distributor to promote, advertise, market, distribute and sell certain products. As a part of this agreement, the Company agreed to pay SeaStar, a milestone payment of $450,000, upon its receipt of a Human Device Exemption (HDE) approval from the U.S. Food and Drug Administration’s (FDA). This payment is due on the later to occur of 30 days after achievement of the milestone event or April 1, 2024. As of December 31, 2023, the Company concluded it was probable HDE approval would be obtained and recorded a liability of $450,000 on the consolidated balance sheet. On February 22, 2024, SeaStar obtained HDE approval.

Fair Value of Financial Instruments, Fair Values Assumptions (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Valuation Technique and Input, Description [Abstract]
Dates and probability of future equity raises	various	various
Risk-Free Interest Rate, Adjusted for Continuous Compounding [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input		0.0397
Risk-Free Interest Rate, Adjusted for Continuous Compounding [Member] \| Minimum [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input	0.0384
Risk-Free Interest Rate, Adjusted for Continuous Compounding [Member] \| Maximum [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input	0.0492
Term [Member]
Valuation Technique and Input, Description [Abstract]
Term		6 years 1 month 9 days
Term [Member] \| Minimum [Member]
Valuation Technique and Input, Description [Abstract]
Term	2 years 9 months 10 days
Term [Member] \| Maximum [Member]
Valuation Technique and Input, Description [Abstract]
Term	3 years
Expected Volatility [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input		1.453
Expected Volatility [Member] \| Minimum [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input	1.411
Expected Volatility [Member] \| Maximum [Member]
Valuation Technique and Input, Description [Abstract]
Measurement input	1.464

Fair Value of Financial Instruments (Tables)

12 Months Ended

Dec. 31, 2023

Fair Value of Financial Instruments [Abstract]

Available-for-Sale Marketable Securities Measured at Fair Value on Recurring Basis

The available-for-sale marketable securities primarily consist of investment-grade, U.S. dollar-denominated fixed and floating-rate debt, measured at fair value on a recurring basis.

	2023				2022
(in thousands)	Fair Value		Level 1		Fair Value		Level 1

Marketable securities		—		—	$	569	$	569

Roll-Forward of Fair Value of Level 3 Warrants

The following is a roll-forward of the fair value of Level 3 warrants:

(in thousands)	2023
Balance at December 31, 2021	$	—
October 18, 2022, issuance of Series I warrants		18,695
Change in fair value		(11,827	)
Balance at December 31, 2022		6,868
Change in fair value		755
Issuance of Common Stock for exercise of Series I warrants		(7,623	)
October 17, 2023, issuance of Series J warrants		4,965
Exercise of Series J warrants		(536	)
Change in fair value		(1,586	)
Balance at December 31, 2023	$	2,483

Fair Value Assumptions

Fair values were calculated using the following assumptions:

	2023			2022
Risk-free interest rates, adjusted for continuous compounding		3.84%-4.92	%		3.97	%
Term (years)		2.78-3.0			6.11
Expected volatility		141.1%-146.4	%		145.3	%
Dates and probability of future equity raises	various			various

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	39,802,000	39,802,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	5,682,461	536,394
Common stock, shares outstanding (in shares)	5,682,461	536,394
Series J Convertible Preferred Stock [Member]
Mezzanine Equity
Mezzanine equity, par value (in dollars per share)	$ 0.0001	$ 0.0001
Mezzanine equity, shares authorized (in shares)	600,000	0
Mezzanine equity, shares issued (in shares)	11,950	0
Mezzanine equity, shares outstanding (in shares)	11,950	0
Series A Junior Participating Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	30,000	30,000
Preferred stock, shares outstanding (in shares)	0	0
Series F Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	18,000	18,000
Preferred stock, shares issued (in shares)	127	127
Preferred stock, shares outstanding (in shares)	127	127
Series I Convertible Preferred Stock [Member]
Stockholders' equity
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	1,049,280	1,049,280
Preferred stock, shares issued (in shares)	0	1,049,280
Preferred stock, shares outstanding (in shares)	0	1,049,280

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
Document and Entity Information - USD ($) $ in Millions	Dec. 31, 2023	Mar. 01, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Amendment Flag	false
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Document Transition Report	false
Entity File Number	001-35312
Entity Registrant Name	NUWELLIS, INC.
Entity Central Index Key	0001506492
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	68-0533453
Entity Address, Address Line One	12988 Valley View Road
Entity Address, City or Town	Eden Prairie
Entity Address, State or Province	MN
Entity Address, Postal Zip Code	55344
City Area Code	952
Local Phone Number	345-4200
Title of 12(b) Security	Common Stock, par value $0.0001 per share
Trading Symbol	NUWE
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 5.0
Entity Common Stock, Shares Outstanding		6,801,443
Auditor Firm ID	23
Auditor Name	Baker Tilly US, LLP
Auditor Location	Minneapolis, Minnesota

Income Taxes, Components of Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Current [Abstract]
United States and state	$ 0	$ 0
Foreign, net	(8)	(9)
Deferred [Abstract]
United States and state	0	0
Foreign	0	0
Total income tax expense	$ (8)	$ (9)

- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2023

Income Taxes [Abstract]

Income Taxes

Note 7—Income Taxes

Domestic and foreign income (loss) before income taxes consists of the following for the years ended December 31:

(in thousands)	2023			2022
Domestic	$	(20,233	)	$	(14,551	)
Foreign		32			35
Loss before income taxes	$	(20,201	)	$	(14,516	)

The components of income tax expense consist of the following for the years ended December 31:

(in thousands)	2023			2022
Current:
United States and state	$	—		$	—
Foreign, net		(8	)		(9	)
Deferred:
United States and state		—			—
Foreign		—			—
Total income tax expense	$	(8	)	$	(9	)

Actual income tax expense differs from statutory federal income tax expense as follows for the years ended December 31:

(in thousands)	2023			2022
Statutory federal income tax benefit	$	4,242		$	3,048
State tax benefit, net of federal taxes		531			783
Foreign tax		(1	)		(1	)
Nondeductible/nontaxable items		(694	)		548
Other		(295	)		(41	)
Valuation allowance (increase) decrease		(3,791	)		(4,346	)
Total income tax expense	$	(8	)	$	(9	)

Deferred taxes consist of the following as of December 31:

(in thousands)	2023			2022
Deferred tax assets:
Noncurrent:
Accrued leave	$	25		$	397
Stock based compensation		285			360
Net operating loss carryforward		48,818			45,405
Other		26			42
Intangibles		2,627			1,786
R&D credit carryforward		531			531
Total deferred tax assets		52,312			48,521
Less: valuation allowance		(52,312	)		(48,521	)
Total	$	—		$	—

As of December 31, 2023, the Company had federal net operating loss (“NOL”) carryforwards of approximately $212.2 million and state NOL carryforwards of $61.7 million. Approximately $119.7 million of federal NOL carryforwards will expire between 2024 and 2037. Pursuant to the Tax Cuts and Jobs Act of 2017, NOLs generated after 2017 of approximately $92.5 million do not expire. The expiration of state NOL carryforwards will vary by jurisdiction. In addition, future utilization of NOL carryforwards in the U.S. may be subject to certain limitations under Section 382 of the Internal Revenue Code. The Company does not have any foreign loss carryovers.

The Company provides for a valuation allowance when it is more likely than not that it will not realize a portion of the deferred tax assets. The Company has established a valuation allowance for U.S. and foreign deferred tax assets due to the uncertainty that enough taxable income will be generated in those taxing jurisdictions to utilize the assets. Therefore, the Company has not reflected any benefit of such deferred tax assets in the accompanying consolidated financial statements. For the years ended December 31, 2023 and 2022, the valuation allowance increased by $3.8 million and $4.3 million, respectively. The current year increase was primarily due to the federal and state net operating losses generated.

During 2023 and 2022, the Company believes it experienced an ownership change as defined in Section 382 of the Internal Revenue Code, which will limit the ability to utilize the Company’s net operating losses (NOLs). The Company may have experienced additional ownership changes in earlier years further limiting the NOL carryforwards that may be utilized. The Company has not yet completed a formal Section 382 analysis. The general limitation rules allow the Company to utilize its NOLs subject to an annual limitation that is determined by multiplying the federal long-term tax-exempt rate by the Company’s value immediately before the ownership change.

The accounting guidance related to uncertain tax positions prescribes a recognition threshold and measurement attribute for recognition and measurement of a tax position taken or expected to be taken in a tax return. It also provides guidance on de-recognition, classification, interest and penalties, accounting in interim periods, disclosure and transition. The Company had no material uncertain tax positions as of December 31, 2023 or 2022.

The Company recognizes interest and penalties on unrecognized tax benefits as well as interest received from favorable tax settlements within income tax expense. At December 31, 2023 and 2022, the Company recorded no accrued interest or penalties related to uncertain tax positions.

The tax years ended December 31, 2020 through December 31, 2023 remain open to examination by the Internal Revenue Service and by the various states where the Company is subject to taxation. Additionally, the returns of the Company’s Irish subsidiary are subject to examination by tax authorities for the tax years ended December 31, 2020 and subsequent years.

- Definition

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480990/946-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(h)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-Name Accounting Standards Codification
-Publisher FASB
-URI https://asc.fasb.org//740/tableOfContent

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 14
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-14

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-21

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 270
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482526/740-270-50-1

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 17
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-17

Reference 8: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I.5.Q1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-1

Reference 9: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 11.C)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479360/740-10-S99-2

Reference 10: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482603/740-30-50-2

+ Details

Nature of Business and Significant Accounting Policies, Loss Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	3,495,757	705,302
Reconciliation of reported net loss with reported net loss per share [Abstract]
Net loss to common stockholders	$ (20,209)	$ (14,525)
Deemed dividend attributable to Series J Convertible Preferred Stock	(2,297)	0
Dividend on Series J Convertible Preferred Stock	(121)	0
Net loss attributable to common stockholders	$ (22,627)	$ (14,525)
Weighted average shares outstanding - basic (in shares)	1,964,406	173,846
Weighted average shares outstanding - diluted (in shares)	1,964,406	173,846
Basic loss per share (in dollars per share)	$ (11.52)	$ (83.55)
Diluted loss per share (in dollars per share)	$ (11.52)	$ (83.55)
Stock Options [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	110,916	10,485
Warrants to Purchase Common Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	2,963,192	679,244
Series F Convertible Preferred Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	125,857	5,080
Series I Convertible Preferred Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	0	10,493
Series J Convertible Preferred Stock [Member]
Potential shares of common stock that are not included in the calculation of diluted net loss per share [Abstract]
Potential shares of common stock that are not included in the calculation of diluted net loss per share (in shares)	295,792	0

Nature of Business and Significant Accounting Policies

12 Months Ended

Dec. 31, 2023

Nature of Business and Significant Accounting Policies [Abstract]

Nature of Business and Significant Accounting Policies

Note 1—Nature of Business and Significant Accounting Policies

Nature of Business

Nuwellis, Inc. (the “Company”) is a medical technology company focused on developing, manufacturing and commercializing the Aquadex FlexFlow® and Aquadex SmartFlow® systems (collectively, the “Aquadex System”) for ultrafiltration therapy. The Aquadex SmartFlow® system is indicated for temporary (up to eight hours) or extended (longer than 8 hours in patients who require hospitalization) use in adult and pediatric patients weighing 20 kg. or more, whose fluid overload is unresponsive to medical management, including diuretics. Nuwellis, Inc. is a Delaware corporation headquartered in Minneapolis with a wholly owned subsidiary in Ireland. The Company has been listed on Nasdaq since February 2012.

In August 2016, the Company acquired the business associated with the Aquadex System (the “Aquadex Business”) from a subsidiary of Baxter International, Inc. (“Baxter”), and refocused its strategy to fully devote its resources to the Aquadex Business. On April 27, 2021, the Company announced that it was changing its name from CHF Solutions, Inc. to Nuwellis, Inc. to reflect the expansion of its customer base from treating fluid imbalance resulting from congestive heart failure to also include critical care and pediatrics applications.

Segment Information

Going Concern

Basis of Presentation

Use of Estimates

Cash and Cash Equivalents

Marketable securities

Accounts Receivable

Inventories

(in thousands)	2023			2022
Finished Goods	$	393		$	993
Work in Process		207			204
Raw Materials		1,472			1,609
Inventory Reserve		(75	)		(145	)
Total	$	1,997		$	2,661

Other Current Assets

Other current assets represent prepayments and deposits made by the Company.

Property, Plant and Equipment

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Depreciation and amortization expense was $362,000 and $372,000 for the years ended December 31, 2023, and 2022, respectively.

There have been no impairment losses recognized for the years ended December 31, 2023, or 2022.

Revenue Recognition

Foreign Currency Translation

Stock-Based Compensation

Income Taxes

Loss per Share

	December 31,
	2023		2022
Stock options		110,916		10,485
Warrants to purchase common stock		2,963,192		679,244
Series F convertible preferred stock		125,857		5,080
Series I convertible preferred stock		—		10,493
Series J convertible preferred stock		295,792		—
Total		3,495,757		705,302

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2023			2022
Net loss to common stockholders	$	(20,209	)	$	(14,525	)
Deemed dividend attributable to Series J Convertible Preferred Stock		(2,297	)		—
Dividend on Series J Convertible Preferred Stock		(121	)		—
Net loss after deemed dividend		(22,627	)		(14,525	)
Weighted average shares outstanding		1,964			174
Basic and diluted loss per share	$	(11.52	)	$	(83.55	)

Research and Development

Recent Accounting Pronouncements

The Company evaluates subsequent events through the date the consolidated financial statements are filed for events requiring adjustment to or disclosure in the consolidated financial statements.

Fair Value of Financial Instruments

12 Months Ended

Dec. 31, 2023

Fair Value of Financial Instruments [Abstract]

Fair Value of Financial Instruments

Note 6—Fair Value of Financial Instruments

The Company’s financial instruments consist of cash and cash equivalents, marketable securities, and warrants.

Pursuant to the requirements of ASC Topic 820 “Fair Value Measurement,” the Company’s financial assets and liabilities measured at fair value on a recurring basis are classified and disclosed in one of the following three categories:

●	Level 1 - Financial instruments with unadjusted quoted prices listed on active market exchanges.

●

Level 2 - Financial instruments lacking unadjusted, quoted prices from active market exchanges, including over-the-counter traded financial instruments. The prices for the financial instruments are determined using prices for recently traded financial instruments with similar underlying terms as well as directly or indirectly observable inputs, such as interest rates and yield curves that are observable at commonly quoted intervals.

●	Level 3 - Financial instruments that are not actively traded on a market exchange. This category includes situations where there is little, if any, market activity for the financial instrument. The prices are determined using significant unobservable inputs or valuation techniques.

All cash equivalents and marketable securities are considered Level 1 measurements for all periods presented.

The available-for-sale marketable securities primarily consist of investment-grade, U.S. dollar-denominated fixed and floating-rate debt, measured at fair value on a recurring basis.

	2023				2022
(in thousands)	Fair Value		Level 1		Fair Value		Level 1

Marketable securities		—		—	$	569	$	569

The fair value of the Company’s common stock warrant liability related to the investor warrants issued in the October 2023 and October 2022 public offerings, were calculated using a Monte Carlo valuation model and were classified as Level 3 in the fair value hierarchy.

The following is a roll-forward of the fair value of Level 3 warrants:

(in thousands)	2023
Balance at December 31, 2021	$	—
October 18, 2022, issuance of Series I warrants		18,695
Change in fair value		(11,827	)
Balance at December 31, 2022		6,868
Change in fair value		755
Issuance of Common Stock for exercise of Series I warrants		(7,623	)
October 17, 2023, issuance of Series J warrants		4,965
Exercise of Series J warrants		(536	)
Change in fair value		(1,586	)
Balance at December 31, 2023	$	2,483

Fair values were calculated using the following assumptions:

	2023			2022
Risk-free interest rates, adjusted for continuous compounding		3.84%-4.92	%		3.97	%
Term (years)		2.78-3.0			6.11
Expected volatility		141.1%-146.4	%		145.3	%
Dates and probability of future equity raises	various			various

A significant change in the inputs used for the Monte Carlo valuation models, such as the expected volatility, risk-free interest rate, or probability of future equity financings, in isolation, would result in significantly higher or lower fair value measurements. In combination, changes in these inputs could result in a significantly higher or lower fair value measurement if the input changes were to be aligned or could result in a minimally higher or lower fair value measurement if the input changes were of a compensating nature.

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Nature of Business and Significant Accounting Policies, Property, Plant and Equipment, Intangible Assets and Revenue Recognition (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2023 USD ($) Customer	Dec. 31, 2022 USD ($) Customer
Property, Plant and Equipment [Abstract]
Depreciation and amortization expense	$ 362	$ 372
Impairment losses recognized	$ 0	$ 0
Production Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Production Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	7 years
Office Furniture and Fixtures [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Office Furniture and Fixtures [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
Computer Software and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Computer Software and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	4 years
Loaners and Demo Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	1 year
Loaners and Demo Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
Leasehold Improvements [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	3 years
Leasehold Improvements [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Estimated useful lives	5 years
ASC 606 [Member] \| Net Sales [Member]
Revenue Recognition [Abstract]
Number of major customers \| Customer	2	1
ASC 606 [Member] \| Customer One [Member] \| Net Sales [Member] \| Customer Concentration Risk [Member]
Revenue Recognition [Abstract]
Concentration risk percentage	13.90%	12.50%
ASC 606 [Member] \| Customer Two [Member] \| Net Sales [Member] \| Customer Concentration Risk [Member]
Revenue Recognition [Abstract]
Concentration risk percentage	12.60%

Revenue Recognition (Details)	12 Months Ended
Revenue Recognition (Details)	Dec. 31, 2023	Dec. 31, 2022
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Abstract]
Expected timing of satisfaction, period		1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Abstract]
Expected timing of satisfaction, period	1 year
Sales Revenue [Member] \| Customer Concentration Risk [Member] \| ASC 606 [Member] \| Maximum [Member]
Revenue, Performance Obligation [Abstract]
Concentration risk percentage	1.00%	1.00%

Nature of Business and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2023

Nature of Business and Significant Accounting Policies [Abstract]

Inventories

Inventories consisted of the following as of December 31:

(in thousands)	2023			2022
Finished Goods	$	393		$	993
Work in Process		207			204
Raw Materials		1,472			1,609
Inventory Reserve		(75	)		(145	)
Total	$	1,997		$	2,661

Estimated Useful Lives

Depreciation expense has been calculated using the following estimated useful lives:

Production Equipment	3-7 years
Office Furniture and Fixtures	3-5 years
Computer Software and Equipment	3-4 years
Loaners and demo equipment	1-5 years
Leasehold improvements	3-5 years

Potential Shares of Common Stock not Included in Diluted Net Loss Per Share

	December 31,
	2023		2022
Stock options		110,916		10,485
Warrants to purchase common stock		2,963,192		679,244
Series F convertible preferred stock		125,857		5,080
Series I convertible preferred stock		—		10,493
Series J convertible preferred stock		295,792		—
Total		3,495,757		705,302

Reconciles Reported Net Loss with Reported Net Loss Per Share

The following table reconciles reported net loss with reported net loss per share for the years ended December 31:

(in thousands, except per share amounts)	2023			2022
Net loss to common stockholders	$	(20,209	)	$	(14,525	)
Deemed dividend attributable to Series J Convertible Preferred Stock		(2,297	)		—
Dividend on Series J Convertible Preferred Stock		(121	)		—
Net loss after deemed dividend		(22,627	)		(14,525	)
Weighted average shares outstanding		1,964			174
Basic and diluted loss per share	$	(11.52	)	$	(83.55	)

Property, Plant and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	$ 4,210	$ 4,151
Accumulated Depreciation	(3,482)	(3,171)
Property, Plant and Equipment, Net	728	980
Depreciation and amortization expense	362	372
Production Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	1,360	1,360
Loaners and Demo Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	1,534	1,444
Computer Software and Equipment [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	688	719
Office Furniture & Fixtures [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	375	375
Leasehold Improvements [Member]
Property, Plant and Equipment, Gross [Abstract]
Property, Plant and Equipment, Gross	$ 253	$ 253

Operating Leases (Details) $ in Thousands	12 Months Ended
Operating Leases (Details) $ in Thousands	Dec. 31, 2023 USD ($) ft² $ / ft²	Dec. 31, 2022 USD ($)
Operating Leases [Abstract]
Area of property leased under operating lease \| ft²	23,000
Monthly rent and common area maintenance charges	$ 34
Annual base rent (per square foot) \| $ / ft²	10.5
Cost Components of Operating Leases [Abstract]
Operating lease cost	$ 249	$ 238
Variable lease cost	142	127
Total	391	$ 365
Maturities of Lease Liability [Abstract]
2024	257
2025	264
2026	272
2027	69
Total lease payments	862
Less: Interest	(102)
Present value of lease liability	$ 760
Remaining lease term	3 years 3 months	4 years 3 months
Discount rate	6.25%	6.25%
Operating cash outflows from operating lease	$ 249	$ 238
Minimum [Member]
Operating Leases [Abstract]
Annual increase per square foot (in dollars per square foot) \| $ / ft²	0.32
Maximum [Member]
Operating Leases [Abstract]
Annual increase per square foot (in dollars per square foot) \| $ / ft²	0.34

Stockholders' Equity (Details) $ / shares in Units, $ in Millions																	12 Months Ended
	Oct. 17, 2023 USD ($) $ / shares shares	Oct. 17, 2023 AUD ($)	Oct. 12, 2023 shares $ / shares	Jun. 19, 2023 Tranche $ / shares shares	Dec. 08, 2022	Dec. 05, 2022	Oct. 18, 2022 USD ($) $ / shares shares	Sep. 17, 2021 USD ($) $ / shares shares	Mar. 19, 2021 USD ($) $ / shares shares	Aug. 21, 2020 USD ($) $ / shares shares	May 05, 2020 USD ($) $ / shares shares	Apr. 01, 2020 USD ($) shares	Mar. 23, 2020 USD ($) $ / shares shares	Jan. 28, 2020 USD ($) $ / shares shares	Mar. 12, 2019 $ / shares	Nov. 27, 2017 USD ($) $ / shares shares	Dec. 31, 2023 USD ($) $ / shares shares	Dec. 31, 2022 $ / shares shares	Sep. 30, 2022 $ / shares	Apr. 02, 2020 $ / shares shares	Nov. 06, 2019 $ / shares	Oct. 25, 2019 $ / shares	May 30, 2019 $ / shares shares	Jul. 03, 2018 $ / shares
Class of Stock Disclosures [Abstract]
Preferred stock, shares outstanding (in shares)																	0	0
Reverse stock split					0.01
Preferred stock, par value (in dollars per share) \| $ / shares																	$ 0.0001	$ 0.0001
Common stock, par value (in dollars per share) \| $ / shares																	$ 0.0001	$ 0.0001
Minimum [Member]
Class of Stock Disclosures [Abstract]
Reverse stock split						0.02
Period of warrants expected to vest																	1 year
Maximum [Member]
Class of Stock Disclosures [Abstract]
Reverse stock split						0.01
Period of warrants expected to vest																	4 years
Maximum [Member] \| Supply Agreement [Member]
Class of Stock Disclosures [Abstract]
Period for ultrafiltration services				10 years
January 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)														5,855
Exercise price of warrants (in dollars per share) \| $ / shares							$ 25						$ 900	$ 1,650					$ 250
Issuance of common stock, net (in shares)														2,015
Public offering price (in dollars per share) \| $ / shares														$ 1,650
Gross proceeds from public stock offering \| $														$ 9,700,000
Net proceeds from public stock offering \| $														8,600,000
Down-round protection in connection with re-pricing of warrants \| $														200,000
Beneficial conversion amount \| $														$ 1,600,000
March 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)													1,387
Exercise price of warrants (in dollars per share) \| $ / shares													$ 1,118
Issuance of common stock, net (in shares)													1,387
Public offering price (in dollars per share) \| $ / shares													$ 900
Gross proceeds from public stock offering \| $													$ 1,200,000
Net proceeds from public stock offering \| $													$ 1,000,000
Warrant expiry period																	5 years 6 months
Warrants exercisable period																	6 months
April 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)																				855
Exercise price of warrants (in dollars per share) \| $ / shares																				$ 1,115
Issuance of common stock, net (in shares)												1,710
Public offering price (in dollars per share) \| $ / shares																				$ 1,302
Gross proceeds from public stock offering \| $												$ 2,200,000
Warrant expiry period																	5 years 6 months
May 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)											600
Exercise price of warrants (in dollars per share) \| $ / shares											$ 1,230
Issuance of common stock, net (in shares)											1,199
Public offering price (in dollars per share) \| $ / shares											$ 1,418
Gross proceeds from public stock offering \| $											$ 1,700,000
Warrant expiry period																	5 years 6 months
August 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)										10,647
Public offering price (in dollars per share) \| $ / shares										$ 1,350
Gross proceeds from public stock offering \| $										$ 14,400,000
Net proceeds from public stock offering \| $										$ 13,000,000
Number of shares issuable on the exercise of warrants (in shares)										10,647
Warrant expiry period																	5 years
March 2021 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)									37,958
Gross proceeds from public stock offering \| $									$ 20,900,000
Net proceeds from public stock offering \| $									$ 18,900,000
September 2021 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)								40,056
Gross proceeds from public stock offering \| $								$ 10,000,000
Net proceeds from public stock offering \| $								$ 9,000,000
October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Gross proceeds from public stock offering \| $							$ 11,000,000
Net proceeds from public stock offering \| $							9,400,000
Financing expense \| $							$ 7,700,000
At-the-Market Program [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)																	657,333
Gross proceeds from public stock offering \| $																	$ 2,300,000
Net proceeds from public stock offering \| $																	$ 2,100,000
Aggregate cash fee paid to underwriter or placement agent																	3.00%
Warrants to Purchase Common Stock [Member]
Class of Stock Disclosures [Abstract]
Number of warrants vested (in shares)																	0
Warrants to Purchase Common Stock [Member] \| Consultant [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)																							33
Exercise price of warrants (in dollars per share) \| $ / shares																							$ 9,540
DaVita Warrant [Member] \| Supply Agreement [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)				1,289,081
Exercise price of warrants (in dollars per share) \| $ / shares				$ 3.2996
Number of warrants vested (in shares)																	0
Common stock, par value (in dollars per share) \| $ / shares				$ 0.0001
Number of tranches \| Tranche				4
DaVita Warrant [Member] \| Supply Agreement [Member] \| Tranche One [Member]
Class of Stock Disclosures [Abstract]
Percentage of warrants expected to vest				25.00%
DaVita Warrant [Member] \| Supply Agreement [Member] \| Tranche Two [Member]
Class of Stock Disclosures [Abstract]
Percentage of warrants expected to vest				25.00%
Period of warrants expected to vest				12 months
DaVita Warrant [Member] \| Supply Agreement [Member] \| Tranche Three [Member]
Class of Stock Disclosures [Abstract]
Percentage of warrants expected to vest				25.00%
Period of warrants expected to vest				24 months
DaVita Warrant [Member] \| Supply Agreement [Member] \| Tranche Four [Member]
Class of Stock Disclosures [Abstract]
Percentage of warrants expected to vest				25.00%
Period of warrants expected to vest				36 months
DaVita Warrant [Member] \| Maximum [Member] \| Supply Agreement [Member]
Class of Stock Disclosures [Abstract]
Warrants to be exercised for amount of shares ownership percentage in entity				19.90%
Common Stock [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)																	657,333	209,940
Common Stock [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)							209,940
Warrants [Member]
Class of Stock Disclosures [Abstract]
Warrants outstanding (in shares)																	6,532	6,532
Warrants [Member] \| October 2023 Offering [Member]
Class of Stock Disclosures [Abstract]
Financing expense \| $		$ 2.7
Gross proceeds before deducting placement agent fees and commissions and offering expenses \| $	$ 2,250,000
Net proceeds after deducting placement agent fees and commissions and offering expenses \| $	$ 1,500,000
Series F Convertible Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Gross proceeds from issuance of convertible preferred stock \| $																$ 18,000,000
Net proceeds from issuance of convertible preferred stock \| $																$ 16,200,000
Conversion price (in dollars per share) \| $ / shares																$ 189,000								$ 89,040
Number of consecutive trading days considered for expiration																	20 days
Number of consecutive trading days																	30 days
Preferred stock issued (in shares)																18,000	127	127
Number of shares issuable on conversion of preferred stock (in shares)																96
Preferred stock, shares outstanding (in shares)																	127	127
Preferred stock, par value (in dollars per share) \| $ / shares																	$ 0.0001	$ 0.0001
Aggregate cash fee paid to underwriter or placement agent															8.00%
Series F Convertible Preferred Stock [Member] \| Minimum [Member]
Class of Stock Disclosures [Abstract]
Percentage of volume weighted average price of common stock																300.00%
Trading volume for each trading day \| $																$ 200,000
Series F Convertible Preferred Stock [Member] \| March 2019 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares															$ 15,750
Series F Convertible Preferred Stock [Member] \| October 2019 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares																						$ 4,230
Series F Convertible Preferred Stock [Member] \| November 2019 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares																					$ 2,983
Series F Convertible Preferred Stock [Member] \| January 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares														$ 1,650
Exercise price of warrants (in dollars per share) \| $ / shares														900
Series F Convertible Preferred Stock [Member] \| March 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares													$ 900
Series F Convertible Preferred Stock [Member] \| March 2021 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares									$ 550
Exercise price of warrants (in dollars per share) \| $ / shares									$ 550
Series F Convertible Preferred Stock [Member] \| September 2021 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares								$ 250
Exercise price of warrants (in dollars per share) \| $ / shares								$ 250
Series F Convertible Preferred Stock [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares							$ 25												$ 250
Series F Convertible Preferred Stock [Member] \| October 2023 Offering [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares			$ 1.01
Series F Convertible Preferred Stock [Member] \| Warrants to Purchase Common Stock [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)																191
Series F Convertible Preferred Stock [Member] \| Warrant Series 1 [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)																16
Exercise price of warrants (in dollars per share) \| $ / shares																$ 189,000
Series F Convertible Preferred Stock [Member] \| Warrant Series 2 [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)																4
Exercise price of warrants (in dollars per share) \| $ / shares																$ 189,000
Series H Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Conversion price (in dollars per share) \| $ / shares														$ 1,650
Maximum percentage of the applicable Unit offering price, by which exercise price can be lower than adjustment														10.00%
Series H Preferred Stock [Member] \| January 2020 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)														115,173
Series I Preferred Stock [Member]
Class of Stock Disclosures [Abstract]
Preferred stock issued (in shares)																	0	1,049,280
Preferred stock, shares outstanding (in shares)																	0	1,049,280
Preferred stock, par value (in dollars per share) \| $ / shares																	$ 0.0001	$ 0.0001
Series I Preferred Stock [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)							23,157,124
Number of shares in one unit (in shares)							1
Class A Unit [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)							209,940
Common stock offering price per share (in dollars per share) \| $ / shares							$ 25
Number of shares in one unit (in shares)							1
Common stock exercise price per share (in dollars per share) \| $ / shares							$ 25
Class A Unit [Member] \| Warrants [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Number of shares in one unit (in shares)							1.5
Class B Unit [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Issuance of common stock, net (in shares)							23,157,124
Common stock offering price per share (in dollars per share) \| $ / shares							$ 0.25
Common stock exercise price per share (in dollars per share) \| $ / shares							$ 0
Class B Unit [Member] \| Warrants [Member] \| October 2022 Offering [Member]
Class of Stock Disclosures [Abstract]
Number of shares in one unit (in shares)							1.5
Series J Convertible Preferred Stock [Member] \| October 2023 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)			0.5
Issuance of common stock, net (in shares)			150,000
Common stock offering price per share (in dollars per share) \| $ / shares			$ 15
Number of shares in one unit (in shares)			1
Preferred stock, par value (in dollars per share) \| $ / shares			$ 0.0001
Number of warrants included in each unit			1
Original issue discount percentage			40.00%
Additional shares issuable upon declaration of dividends (in shares)			362,933
Series J Convertible Preferred Stock [Member] \| Common Stock [Member] \| October 2023 Offering [Member]
Class of Stock Disclosures [Abstract]
Common stock, par value (in dollars per share) \| $ / shares			$ 0.0001
Series J Convertible Preferred Stock [Member] \| Warrants [Member] \| October 2023 Offering [Member]
Class of Stock Disclosures [Abstract]
Warrants to purchase shares of common stock (in shares)	0.5
Exercise price of warrants (in dollars per share) \| $ / shares	$ 7.5
Warrants term	3 years

Income Taxes, Deferred Taxes and Other Information (Details) $ in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2020 AUD ($)
Noncurrent [Abstract]
Accrued leave	$ 25	$ 397
Stock based compensation	285	360
Net operating loss carryforward	48,818	45,405
Other	26	42
Intangibles	2,627	1,786
R&D credit carryforward	531	531
Total deferred tax assets	52,312	48,521
Less: valuation allowance	(52,312)	(48,521)
Total	0	0
Operating Loss Carryforwards [Abstract]
Increase in valuation allowance	3,800	4,300
Unrecognized Tax Benefits [Abstract]
Uncertain tax positions	0	0
Penalties and Interest Accrued [Abstract]
Interest and penalties accrued on uncertain tax positions	$ 0	$ 0
Earliest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards, expiration date	Dec. 31, 2024
Latest Tax Year [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards, expiration date	Dec. 31, 2037
Federal [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards	$ 212,200
Net operating loss (NOL) carryforwards with expiration date	119,700
Net operating loss (NOL) carryforwards with no expiration date	92,500
State [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards	$ 61,700
Foreign [Member]
Operating Loss Carryforwards [Abstract]
Net operating loss (NOL) carryforwards			$ 0