HCPCS code A4575: Oxygen chamber, disposable topical2026 Medicare rate & RVUs

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

What A4575 covers

A4575 identifies a disposable chamber used to apply oxygen under pressure to a localized body area, commonly a wound. Unlike whole-body hyperbaric oxygen treatment, topical treatment places the affected area in the chamber. The item may be furnished by a wound-care practice or another provider involved in the treatment; the code represents the chamber, not the clinical service itself.

Medicare assigns A4575 physician fee schedule status X because it is not a physician service; the physician fee schedule never pays it. The HCPCS pricing method classifies it as not separately priced by Medicare Part B. When covered, it is paid under another fee schedule or payment system, and coverage is left to the Medicare contractor’s judgment. A4575 represents the disposable chamber item rather than the clinical service.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where A4575 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 of 109 payment localities

A4575 rates by state

Office rate range in each state. Select a state to see its payment localities.

How the A4575 rate is calculated

Each of A4575’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

Payment rules and modifiers for A4575

A4575 has no global surgery period, no multiple-procedure, bilateral or assistant-at-surgery adjustment, and no professional/technical split. What changes the payment is where the service happens: the place of service on the claim decides whether Medicare pays the office or the facility rate.

A4575 compared with similar codes

How to choose

G0277Hyperbaric oxygenFull-body chamber, per 30 minutes

G0277 reports a facility hyperbaric oxygen treatment service by time. A4575 identifies a disposable topical chamber, not a treatment service.

99183Hyperbaric oxygenProfessional service

99183 reports physician attendance and supervision of hyperbaric oxygen therapy. A4575 identifies the topical chamber itself.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Open CMS sourceHow we calculate rates