Codes without
the hunt.
The codes, crosswalks, and payer notes for hyperbaric oxygen therapy in one place — so a claim doesn't stall on paperwork.
Procedure codes
99183
Physician attendance and supervision of hyperbaric oxygen therapy, per session
A4575
Topical hyperbaric oxygen chamber, disposable
Not the same as systemic HBOT — do not substitute for G0277.
C1300
Hyperbaric oxygen under pressure, full body chamber, per 30-minute interval (hospital outpatient)
G0277
Hyperbaric oxygen under pressure, full body chamber, per 30-minute interval
G0277 units calculator
HCPCS G0277 bills per 30-minute interval. Enter the chamber time to get billable units.
Billable units
3
Units = chamber time ÷ 30 (rounded to payer policy). Confirm rounding rules with the specific payer.
ICD-10 by indication
| Condition | ICD-10 | FDA | Medicare |
|---|---|---|---|
| Carbon Monoxide Poisoning | T58.11XA | ✓ | ✓ |
| Decompression Sickness | T70.3XXA | ✓ | ✓ |
| Delayed Radiation Injury | M27.2 | ✓ | ✓ |
| Diabetic Foot Ulcers | E11.621, L97.509 | ✓ | ✓ |
| Sudden Sensorineural Hearing Loss | H91.20 | ✓ | — |
Per-payer notes
Aetna
Covers recognized indications per its Clinical Policy Bulletin; requires documentation mirroring NCD 20.29. Off-label uses considered experimental.
Blue Shield
Commercial plans generally follow Medicare's indication list with prior authorization. Off-label uses (e.g. TBI, long COVID) are excluded.
Cigna
Aligns with Medicare's covered indications; prior authorization and periodic reauthorization for extended wound courses.
Medicaid / Medi-Cal
Follows Medicare's recognized-indication list; specifics and prior-auth vary by state. In California, Medi-Cal generally aligns with NCD 20.29.
Medicare
Covers the 14 UHMS-recognized indications under NCD 20.29 (plus diabetic lower-extremity wounds meeting Wagner III+ / 30-day criteria). Part B pays 80% after deductible. Documentation of failed standard care is the usual denial point.
UnitedHealthcare
Covers recognized indications with prior authorization; medical-necessity review common for wound-care courses beyond initial approval.
Coding guidance is educational and current to our best knowledge — verify against each payer's active policy and the latest CMS determinations. Medicare policy: NCD 20.29.