Topical Oxygen Oxygen chambers / Topical Oxygen Chambers for Extremities. The chamber provides intermittent pressure up to 50 mmHg, cycling / ramping from 0 mmHg to 50 mmHg of pressure over a 15 to 20 second cycle, then venting back to 0mmHg of pressure within 5 seconds.

AI/ML Overview

The provided text does not describe a study involving detailed acceptance criteria and performance data for a device in the manner typical for AI/ML medical devices. Instead, it is a 510(k) premarket notification summary for a "Topical Oxygen Chamber for Extremities" (HEC 1000). The document discusses safety concerns related to pressure levels and how the device's intermittent pressure design (cycling from 0 mmHg to 50 mmHg) addresses these concerns, differentiating it from devices with continuous pressure exceeding 22 mmHg.

Therefore, many of the requested points from the prompt (e.g., sample size for test set, number of experts for ground truth, MRMC study, sample size for training set) are not applicable as this isn't an AI/ML device where such studies are typically performed.

However, I can extract information related to the device's operational characteristics and the rationale for its safety, which serves as a form of "acceptance criteria" for its safe operation in the context of the 510(k) submission.

Here's the information derived from the provided text, adapted to the prompt's structure where possible:

Acceptance Criteria and Device Performance for Topical Oxygen Chamber (HEC 1000)

1. Table of Acceptance Criteria and Reported Device Performance

Acceptance Criteria Category	Specific Criteria (from document)	Reported Device Performance (from document)
Safety - Pressure	Address concern of occluding arterial circulation due to continuous pressure > 22 mmHg: - Avoid prolonged, continuous pressure above 22 mmHg. - Allow for capillary refill time.	The HEC 1000 provides intermittent pressure up to 50 mmHg. - Cycles from 0 mmHg to 50 mmHg with an average fill time of less than 25 seconds. - Applies pressures above 22 mmHg for no longer than 15 seconds before venting to nearly 0 mmHg for 3-4 seconds. - Pressures less than 22 mmHg are applied for approximately 15 seconds. - Safety risk of capillary occlusion is minimized by limiting time above 22 mmHg to ~15 seconds and allowing ~15 seconds for capillary refill. - Worst-case scenario (if failing to reach 50mmHg within 60s): Pressures > 22 mmHg for no greater than 45 seconds, then vents and holds at nearly 0 mmHg.
Safety - Pressure Relief	Prevent prolonged constant pressures above 22 mmHg even in case of malfunction.	- Software design: If the set pressure (50 mmHg) is not achieved within 60 seconds (implying the unit would reach 22 mmHg in ~15s, thus being above for ~45s), the software automatically vents the chamber and remains on hold. - Hardware design: Unit is designed with a pressure relief valve to vent automatically upon reaching 50 mmHg of pressure. - These built-in redundancies address safety concerns of exceeding prolonged constant pressures above 22 mmHg.
Safety - Infection	Device material/construction should not prevent proper disinfection.	(Not explicitly detailed in the provided text beyond stating the concern)
Safety - Fire	Mitigate hazards of pure oxygen when an open flame is present.	(Not explicitly detailed in the provided text beyond stating the concern)
Effectiveness (Limitations)	Device has diminished/no effectiveness for ulcers/wounds associated with: - Severe ischemic disease. - Raynaud's Disease. - Acute/chronic ischemic disease secondary to thrombosis, embolism. - Avascularity (absent blood supply). - Osteomyelitis. - Wounds not adequately debrided of necrotic tissue. - Wounds not irrigated clean of topical ointments (required removal of dressings).	Implicitly, the device is effective for conditions outside of these stated limitations when used with proper wound preparation (debridement, irrigation, dressing removal). The submission cites various studies (see point 3) supporting the effectiveness of topical oxygen therapy generally, rather than providing specific performance data for the HEC 1000 against a defined effectiveness metric.

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

Not applicable (N/A). This is a 510(k) submission for a physical medical device (Topical Oxygen Chamber), not an AI/ML device that typically involves a "test set" in this context. The safety assessment relies on device design considerations ("chamber performance qualification testing" with "actual data in section G" which is not provided in the extract) and a review of existing medical literature and adverse event databases, not a specific clinical "test set" for performance evaluation in the AI/ML sense.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)

Not applicable (N/A). "Ground truth" in the AI/ML sense, requiring expert consensus on a test set, is not relevant here. The "ground truth" for the device's safety and effectiveness relies on established medical understanding of oxygen therapy, circulatory physiology, and clinical experience, as evidenced by citations and letters from medical professionals like "Dr. Benjamin" and "Dr. Hess" (see point 9 for more detail on their input).

4. Adjudication method (e.g. 2+1, 3+1, none) for the test set

Not applicable (N/A). No "test set" or adjudication in the AI/ML context.

5. If a multi reader multi case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

Not applicable (N/A). This is not an AI-assisted device.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

Not applicable (N/A). This is not an algorithm. The device operates independently of human interpretation of its outputs, but requires human intervention for application and patient monitoring.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)

The "ground truth" for the safety claims (specifically regarding pressure and circulation) is based on physiological principles (capillary occlusion pressure of 22 mmHg) and clinical experience (Dr. Benjamin's letter on over 400 patients using intermittent chambers).
For effectiveness, the "ground truth" is derived from published medical literature/clinical studies (cited in section 3 of the document) and general understanding of wound healing and oxygen therapy.

8. The sample size for the training set

Not applicable (N/A). There is no "training set" as this is not an AI/ML device.

9. How the ground truth for the training set was established

Not applicable (N/A). As there is no training set, this point is not relevant. However, the basis for the safety assertions includes:
- "Chamber performance qualification testing" (data in section G, not provided) for the HEC 1000's operational parameters (fill time, venting).
- Clinical experience and expert opinion: A "letter from Dr. Benjamin" (cited in section F and 3.12) regarding his experiences using intermittent chambers on "over 400 patients" is referenced to support the safety profile of intermittent pressure. Another letter from "R. Hess" (cited in section 3.13) is also mentioned.
- Review of adverse event databases: Searches of MDR (Manufacturer and User Facility Device Experience) and MAUDE (Manufacturer and User Facility Device Experience) databases to confirm no reported adverse reactions specifically to topical oxygen chambers.

Summary

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KO20466

SUMMARY OF 510-K SAFETY AND EFFECTIVENESS

Topical Oxygen Oxygen chambers / Topical Oxygen Chambers for Extremities

EFFECTIVENESS PROBLEMS:

Topical oxygen oxygen has diminished or no effectiveness when treating:

1.) Ulcers / Wounds associated with the following:
- severe ischemic disease .
- Raynaud's Disease ●
- Acute or chronic ischemic disease secondary to thrombosis, embolism .
- Avascularity (absent blood supply) .
- Osteomyelitis .
1. ) Ulcers / wounds that have not been adequately debrided of necrotic tissue. Dead tissue will not allow oxygen to penetrate and oxygenate the tissue.
1. Ulcers / wounds that have not been irrigated clean of any topical ointments that may cause a barrier over the wound, preventing the penetration of oxygen into the viable tissue. [All wound dressings must be removed to expose tissue to oxygen]

SAFETY

Upon reviewing MDR, there are no reported adverse reactions to topical oxygen oxygen chambers. However, the following adverse safety concerns should be observed:

1. } Infection: Infection may result if the material used in the device or its contruction prevent proper disinfection.
2.) Fire: Pure oxygen required in oxygen chambers is highly combustible and hazardous when an open flame is present.
3.) Decrease in local tissue circulation:

Greater than 22 mmHg of continuous oxygen pressure in the chamber, may occlude arterial circulation, leading to a decrease in local tissue circulation.

Note: Our chamber requesting 510k clearance and the two predicate chambers mentioned in our premarket notification, provide up tp 50mmHg of pressure intermittently, cycling / ramping from 0 mmHg to 50 mmHg of pressure over a 15 to 20 second cycle *, then venting back to 0mmHg of pressure within 5 seconds. This cycling or intermittent compression will not have the same degree of safety Concern as a constant, non-intermittent pressure on the extremity. (See letter from Dr. Benjamin in section F. Cycle times may vary dependent on liter flow and the degree to which the the chamber volume is reduced by the limb, positioning pads, etc.

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4.) Oxygen chambers that apply oxygen under positive intermittent (pulsed) pressure are contraindicated for use in the presence of acute thrombophlebitis, as the pressure variations may dislodge the thrombus.
5.) Allergic reactions: Sleeve used to seal the extremity inside the chamber contains natural rubber latex which may cause allergic reaction.

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Discussion of Pressures above 22 mmHg:

In the Federal Register notice dated January 19, 1982, volume 47, #12, page 2645, a statement is made addressing the possibility of occluding blood flow to tissues when pressures exceed 22 mmHg. This may be a valid concern when it applies to the topical oxygen chambers that place the extremity inside of a plastic bag and inflate the bag with oxygen to a constant / continuous pressure of 22 mmHg for time periods of one hour or more. (i.e. - GWR - O2 Boot / Lifetech Systems- Lifetech Cassette / Oxycure -Boot)

Metro Medicals chamber and the predicate devices cited in this submission by: Topox / Advanced Hyperbaric Technologies, Inc. and Stephenson Industries are also classified as topical oxygen chambers for extremities, however, there are some major differences in their design and operation which should be addressed as they relate to the safety concerns of chambers that exceed 22 mmHg.

The big difference is that the chambers provide intermittent pressure up to 50 mmHg and do not exceed 22 mmHg for more than 15 to 30 seconds before they vent to nearly 0mmHg.

In our chamber performance qualification testing (see actual data in section G) the HEC 1000 cycled from 0mmHg to 50mmHg with an average fill time of less than 25 seconds. Therefore, the amount of time that the unit is actually applying pressures above 22 mmHg would be no longer than 15 seconds before venting to nearly 0 mmHg for the next 3 to 4 seconds. The following cycle begins to pressurize and will exceed 22 mmHg in approximately 12 to 15 seconds before reaching the set pressure of 50mmHg under 25 seconds. (See letter from Dr. Benjamin in section F regarding his experiences using the intermittent chambers on over 400 patients.)

In summary, the chamber will apply pressures above 22mmHg for approximately 15 seconds and pressures less than 22 mmHg for approximately 15 seconds. The safety risk of capillary occlusion is minimized by limiting the length of time to no more than 15 seconds above 22 mmHg and allowing approximately 15 seconds for capillary refill to take place. There is a much greater risk of reducing blood flow to the tissues when a constant pressure is applied. Even if the unit failed to reach its set maximum pressure of 50mmHg. the software would automatically vent the chamber and remain on hold, if the set pressure was not achieved within 60 seconds. Assuming that the unit would reach 22 mmHg within approximately 15 seconds, the worst case scenario would be that the extremity would be under pressures greater than 22 mmHg for no greater than 45 seconds then vent and hold at nearly 0 mmHg until the continue screen was pressed. In addition, the unit is designed with a pressure relief valve to vent automatically upon reaching 50 mmHg of pressure. This built in redundancy of the 60 second timer and pressure relief valve addresses any safety concerns of exceeding prolonged constant pressures above 22 mmHg. A review of MDR and MAUDE data bases turns up no reported claims of adverse reactions resulting from topical oxygen chambers for extremities.

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CITATIONS / SEARCH METHODOLOGY AND REFERENCES FOR SAFETY AND EFFECTIVENESSS STATEMENTS:

1. Search of MDR and MAUDE databases for reports on any adverse reports relating to topical oxygen oxygen chambers.
1. ) Code of Federal Regulations pertaining to the classification of topical oxygen chambers for extremities. ( 21 CFR 878.5650)
1. ) Fisher, Boguslav. Treatment of Ulcers on the legs with Hyperbaric Oxygen. Journal of Dermatologic Surgury, Inc. 1975; 3:55-58
1. ) Heng, MCY: Topical Oxygen Therapy for Problem Skin Wounds. Dermatol Surgury Oncology 19:784-793, 1993
1. ) Lehman WL, Jones WW, Allo MD, Johnston RM. Human Bite Infections of the Hand: Adjunct treatment with Hyperbaric Oxygen. Infections in Surgery 1985; 460-465.
6.) Williams RL, Hyperbaric Oxygen Therapy and the Diabetic Foot. Journal of American Podiatric Medical Association. 1997; 279-291.
7.) Heng MCY, Harker J, Bardakjian VB, Ayvazian H, Enhanced Healing and Cost Effectiveness of Low Pressure Oxygen Therapy in Healing Necrotic Wounds. Ostomy Wound Management 2000: 46(3); 52-62
8 ) Rossi F. Elsinger E. Topical Hyperbaric Oxygen Therapy for Lower-Extremity Wound Care: An Overview. Podiatry Management, November 1997; 110-111
9.) Diamond E, Forst MB, Hyman SA, Rand SA, The Effect of Hyperbaric Oxygen on Lower Extremity Ulcerations. Journal of he American Podiatry Association, Volume 72, Number 4, April 1972; 180-184
- 10.) Rehm KB, Goudberg D. Longobardi J. Tidwell G. THBO: Putting Pressure On Non-Healing Wounds. Podiatry Today, December 1997; 54,56,64,65
- 11.) Olejniczak S. Zielinski A. Eloise, Low Oxygen Therapy in Management of Leg Ulcers. Michigan Medicine, Volume 74, Number 32. November 1975; 707-712
- 12.) Benjamin RS, Letter Addressing Safety and Effectiveness Of THBO, November 29, 2001
- 13.) Hess R, Letter addressing safety and effectiveness of THBO, May 2, 2001

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Image /page/4/Picture/1 description: The image shows the logo for the Department of Health & Human Services - USA. The logo features a stylized image of an eagle with three heads, representing the department's mission to protect the health of all Americans and provide essential human services. The words "DEPARTMENT OF HEALTH & HUMAN SERVICES - USA" are arranged in a circular pattern around the eagle.

MAY 0 8 2002

Food and Drug Administration 9200 Corporate Boulevard Rockville MD 20850

Mr. Paul Mocur President Metro Medical Manufacturing, Inc. 12985 Wayne Road Livonia, MI 48150

Re: K020466

Trade/Device Name: Topical (O2) Oxygen Chamber for Extremities Regulation Number: 878.5650 Regulation Name: Topical oxygen chamber for extremities Regulatory Class: III Product Code: KPJ Dated: February 8, 2002 Received: February 12, 2002

Dear Mr. Mocur:

We have reviewed your Section 510(k) premarket notification of intent to market the device w ferenced above and have determined the device is substantially equivalent (for the indications for use stated in the enclosure) to legally marketed predicate devices marketed in interstate commerce prior to May 28, 1976, the enactment date of the Medical Device Amendments, or to devices that have been reclassified in accordance with the provisions of the Federal Food, Drug, and Cosmetic Act (Act) that do not require approval of a premarket approval application (PMA). You may, therefore, market the device, subject to the general controls provisions of the Act. The general controls provisions of the Act include requirements for annual registration, listing of devices, good manufacturing practice, labeling, and prohibitions against misbranding and adulteration.

If your device is classified (see above) into either class II (Special Controls) or class III (PMA), it may be subject to such additional controls. Existing major regulations affecting your device can be found in the Code of Federal Regulations, Title 21, Parts 800 to 898. In addition, FDA may publish further announcements concerning your device in the Federal Register.

Please be advised that FDA's issuance of a substantial equivalence determination does not mean that FDA has made a determination that your device complies with other requirements of the Act or any Federal statutes and regulations administered by other Federal agencies. You must comply with all the Act's requirements, including, but not limited to: registration and listing (21 CFR Part 807); labeling (21 CFR Part 801); good manufacturing practice requirements as set forth in the quality systems (QS) regulation (21 CFR Part 820); and if applicable, the electronic product radiation control provisions (Sections 531-542 of the Act); 21 CFR 1000-1050.

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Page 2 -- Mr. Paul Mocur

This letter will allow you to begin marketing your device as described in your Section 510(k) premarket notification. The FDA finding of substantial equivalence of your device to a legally marketed predicate device results in a classification for your device and thus, permits your device to proceed to the market.

If you desire specific advice for your device on our labeling regulation (21 CFR Part 801 and additionally 21 CFR Part 809.10 for in vitro diagnostic devices), please contact the Office of Compliance at (301) 594-4659. Additionally, for questions on the promotion and advertising of your device, please contact the Office of Compliance at (301) 594-4639. Also, please note the regulation entitled, "Misbranding by reference to premarket notification" (21CFR Part 807.97). Other general information on your responsibilities under the Act may be obtained from the Division of Small Manufacturers, International and Consumer Assistance at its toll-free number (800) 638-2041 or (301) 443-6597 or at its Internet address http://www.fda.gov/cdrh/dsma/dsmamain.html

Sincerely yours,

Miriam C. Provost

for Celia Witten, Ph.D., M.D. Director Division of General, Restorative and Neurological Devices Office of Device Evaluation Center for Devices and Radiological Health

Enclosure

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510(K) Number (if krown): K020466

Device Name: HEC 1000 | Topical Oxygen Chamber for Extremities]

Indications For Use:

" STATEMENT OF INDICATIONS FOR USE "

Q Burns
Post Surgical Infections は
Venous Stasis Ulcers G
Diabetic Ulcers C
Frostbite 山
Amputations / Infected Stumps এ
Skin Grafts €

(PLEASE DO NOT V/RITE BELOW THIS LINE-CONTINUE ON ANOTHER PAGE IF NEEDED)

Concarrence of CDRH, Office of Device Evaluation (ODE)

Prescription Use (Per 21 CFR 801.109) OR

Over-The-Counter Use

(Optional Format 1-2-96 )

iriam C. Provost

Division Sign-Off) (Division Sign-Off)
Division of General, Restorative
Division of General, Devices Division of General, 100 -KO204bb

510(k) Number -

Regulation Number and Section

§ 878.5650 Topical oxygen chamber for extremities.

(a)
Identification. A topical oxygen chamber for extremities is a device that is intended to surround a patient's limb and apply humidified oxygen topically at a pressure slightly greater than atmospheric pressure to aid healing of chronic skin ulcers such as bedsores.(b)
Classification. Class II (special controls). The special control for this device is FDA's “Class II Special Controls Guidance: Topical Oxygen Chamber for Extremities.” See § 878.1(e) for the availability of this guidance document.