Hyperbaric Oxygen Therapy Referral: When to Send Patients

Hyperbaric Oxygen Therapy Referral for Wound Care Patients

Hyperbaric oxygen therapy (HBOT) delivers 100% oxygen at pressures greater than atmospheric pressure, typically 2.0-2.4 atmospheres absolute (ATA), in a pressurized chamber. For wound care practitioners, HBOT is not a first-line treatment — it is an adjunctive therapy reserved for specific wound types that have failed to respond to standard wound care over a defined treatment period. Knowing when to refer, what documentation to provide, and which patients will actually benefit from HBOT separates appropriate utilization from overuse.

This guide covers the clinical decision-making process for hyperbaric oxygen therapy referral in wound care practice.

HBOT Indications in Wound Care

The Undersea and Hyperbaric Medical Society (UHMS) recognizes 14 approved indications for HBOT. The wound-related indications most relevant to wound care practitioners are:

Diabetic Lower Extremity Wounds

This is the most common wound care referral indication for HBOT. Medicare covers HBOT for diabetic patients with a Wagner Grade III or higher lower extremity wound who have failed an adequate course of standard wound care.

The specific Medicare criteria:

Patient has type 1 or type 2 diabetes
Wound is Wagner Grade III (deep ulcer with abscess, osteomyelitis, or joint sepsis) or higher
Patient has failed 30 days of standard wound care, which must include:
- Assessment and optimization of vascular status
- Optimization of glycemic control
- Debridement of necrotic tissue
- Moist wound healing environment
- Offloading
- Treatment of any infection
No measurable improvement after the standard care period

Chronic Refractory Osteomyelitis

When osteomyelitis persists despite appropriate antibiotic therapy and surgical debridement, HBOT enhances white blood cell killing function at the bone level and promotes osteogenesis. This is particularly relevant for wound care patients whose foot ulcers have progressed to bone involvement.

Compromised Skin Grafts and Flaps

When a skin graft or flap shows signs of compromise — marginal perfusion, partial necrosis, or delayed take — HBOT can improve oxygen delivery to the tissue during the critical early healing period. The referral should be timely: within the first few days of identifying graft compromise, not after the graft has fully failed.

Soft Tissue Radiation Necrosis

Patients with wounds in previously irradiated tissue fields may benefit from HBOT. Radiation damages the microvasculature permanently, creating a hypoxic wound bed that cannot support healing through standard wound care alone. HBOT stimulates angiogenesis in irradiated tissue.

For CPT code references related to wound care procedures performed alongside HBOT referral, see our wound care CPT codes 2026 guide.

Contraindications: When Not to Refer

Absolute and relative contraindications must be assessed before making a referral:

Absolute Contraindications

Untreated pneumothorax — pressure changes can cause fatal tension pneumothorax
Concurrent use of certain chemotherapy agents (doxorubicin, cisplatin, bleomycin, disulfiram) — HBOT may potentiate toxicity

Relative Contraindications

Active upper respiratory infection or sinus congestion — inability to equalize pressure
Seizure disorder — oxygen toxicity can lower seizure threshold
Claustrophobia — monoplace chambers may trigger anxiety (multiplace chambers are better tolerated)
COPD with CO2 retention — high-concentration oxygen can suppress respiratory drive
Implantable devices — pacemakers and other implanted devices must be confirmed as pressure-compatible
Pregnancy — limited safety data; generally avoided unless the indication is emergent

Patients Who Will Not Benefit

Even when the indication is present, certain patients are poor HBOT candidates:

Patients with an ABI < 0.4 or TCPO2 < 100 mmHg in the hyperbaric chamber (unable to achieve adequate tissue oxygen levels even with pressurized oxygen)
Patients who are non-adherent with basic wound care (HBOT will not compensate for failure to offload, control glucose, or manage infection)
Patients whose wounds are not being concurrently managed with appropriate standard wound care

Hyperbaric Oxygen Referral Documentation

A complete HBOT referral should include documentation that supports both clinical appropriateness and payer requirements:

Required Documentation Elements

Wound history and duration — how long the wound has been present, with objective measurements over time showing lack of progress
Standard care provided — itemized list of treatments attempted, with dates and outcomes
30-day failure documentation — objective evidence (wound measurements, photographs) demonstrating that the wound has not responded to appropriate care over at least 30 days
Wagner classification (for diabetic foot ulcers) — document the specific grade and the clinical findings that support it
Vascular assessment — ABI, TBI, or TCPO2 results confirming adequate arterial supply to support HBOT
Glycemic status — recent HbA1c and blood glucose trends
Infection status — current infection assessment and any treatment in progress
Wound photographs — baseline and serial photos documenting wound trajectory

Pre-Referral Optimization

Before referring, ensure you have optimized everything within your scope:

Sharp debridement of all non-viable tissue
Appropriate offloading device in place and confirmed adherent
Glycemic control addressed (communicate with PCP/endocrinologist if A1c > 8%)
Nutrition assessed and supplementation initiated if needed (prealbumin, albumin)
Any active infection treated or resolved
Smoking cessation discussed (smoking dramatically reduces HBOT efficacy)

Medicare HBOT Coverage Criteria

Medicare covers HBOT under specific conditions. Understanding these criteria helps wound care practitioners make appropriate referrals and avoid denials for the receiving HBOT facility. For broader LCD compliance guidance, see our wound care LCD compliance guide.

Coverage Requirements

Medicare requires:

The wound meets a covered indication (diabetic lower extremity wound is most common)
30 days of standard wound care has been documented
No measurable signs of healing during the standard care period
TCPO2 testing confirms the wound is hypoxic but responsive to oxygen (in-chamber TCPO2 should be > 200 mmHg for adequate treatment response prediction)

Treatment Parameters

Covered HBOT is typically:

90-minute treatment sessions at 2.0-2.4 ATA
5 days per week
Initial authorization for 30 treatments
Reassessment at 30 treatments — continued authorization requires demonstrated measurable wound improvement

TCPO2 as a Selection and Monitoring Tool

Transcutaneous oxygen pressure measurement plays a dual role in HBOT referral:

Selection: A periwound TCPO2 < 40 mmHg on room air indicates wound hypoxia and suggests the wound may benefit from enhanced oxygen delivery. An in-chamber TCPO2 > 200 mmHg confirms the tissue can respond to hyperbaric oxygen.

Monitoring: Serial TCPO2 measurements during the HBOT course can predict treatment response. Patients whose periwound TCPO2 does not improve with treatment are unlikely to benefit from continued sessions.

Coordinating Care During HBOT

Patients receiving HBOT continue to need wound care. The wound care practitioner's role during HBOT includes:

Continuing regular wound care visits for debridement, dressing changes, and monitoring
Communicating with the HBOT team regarding wound status and treatment response
Documenting wound measurements at consistent intervals for comparison
Adjusting the wound care plan based on response (or lack of response) to combined therapy
Preparing for advanced interventions (skin substitutes, grafting) once the wound bed is optimized through HBOT

Key Takeaways

HBOT is adjunctive therapy, not a standalone treatment — patients must be receiving concurrent appropriate wound care including debridement, offloading, and infection management
The most common wound care HBOT referral is for Wagner Grade III+ diabetic foot ulcers that have failed 30 days of documented standard care
Pre-referral optimization is the wound care practitioner's responsibility — debride, offload, address glycemic control, treat infection, and assess nutrition before referring
TCPO2 testing is both a selection tool and a monitoring tool — periwound values below 40 mmHg indicate hypoxia, and in-chamber values above 200 mmHg predict treatment response
Medicare authorizes HBOT in 30-treatment blocks with mandatory reassessment demonstrating measurable improvement before continuation