UHMS Position Statement: Why Standardising the Term HBO2 Matters for Patients and Clinicians

Words carry weight in medicine. The name given to a treatment shapes how it is researched, regulated, reimbursed, and understood by patients and clinicians alike. When terminology is inconsistent, the consequences extend well beyond semantics: clinical evidence becomes harder to compare, regulatory frameworks become harder to apply, and patients face a landscape in which the same intervention is described in ways that obscure rather than clarify.

The Undersea and Hyperbaric Medical Society (UHMS) has addressed this directly through a formal position statement calling for the consistent use of the term HBO2 as the standard abbreviation for hyperbaric oxygen therapy. The statement is a concise but clinically significant document, and its implications reach further than the abbreviation itself.

---

What the UHMS Position Statement Says

The UHMS position statement on the standardisation of hyperbaric oxygen terminology makes a clear and specific recommendation: the abbreviation HBO2 should be adopted as the standard term across clinical, research, and educational contexts.

The rationale is straightforward. Hyperbaric oxygen therapy has historically appeared in the literature and in clinical settings under a range of abbreviations and descriptors, including HBOT, HBO, OHB, and various others depending on language, country of origin, and institutional preference. This fragmentation creates practical problems.

When a clinician searches the published literature for evidence on hyperbaric oxygen, inconsistent terminology means that relevant studies may not surface in a search using one abbreviation but not another. When a researcher designs a trial, the choice of terminology affects how the work is indexed and how it connects to the broader body of evidence. When a patient or referring physician reads a clinical summary, inconsistent naming can create confusion about whether different terms refer to the same intervention or to variations of it.

The UHMS position is that HBO2 is the most precise and unambiguous descriptor. The subscript numeral 2 explicitly denotes molecular oxygen (O2), distinguishing the therapy from other uses of the word "oxygen" in clinical contexts and from hyperbaric exposures that do not involve supplemental oxygen. This precision is not pedantic. It is the kind of specificity that clinical medicine depends on.

The full position statement is available for reference: UHMS Position Statement: Standardization of the HBO2 Term (PDF)

---

Why Terminology Precision Matters in Hyperbaric Medicine

Hyperbaric medicine occupies an unusual position in the clinical landscape. It is a well-established specialty with decades of peer-reviewed evidence, formal training pathways, and recognised professional bodies. It is also a field that has attracted a significant volume of unregulated commercial activity, unsupported claims, and consumer-facing marketing that frequently blurs the line between clinical therapy and wellness services.

In that context, precise terminology is not merely a matter of academic tidiness. It is a tool for maintaining the integrity of the clinical evidence base and for distinguishing legitimate medical practice from unregulated alternatives.

When the same abbreviation is used to describe a physician-supervised course of treatment in a certified multiplace chamber and a session in an unregulated low-pressure soft-shell device marketed for home use, the terminology itself becomes a source of confusion. Patients researching their options cannot easily distinguish between these very different interventions if the language used to describe them is interchangeable.

Standardising on HBO2 as the clinical term creates a clearer boundary. It signals that the reference is to hyperbaric oxygen therapy as defined and practised within the medical and scientific community, not to the broader and often poorly defined category of "hyperbaric" products and services available in the consumer market.

---

The UHMS and Its Role in Setting Clinical Standards

The Undersea and Hyperbaric Medical Society is the principal professional and scientific organisation for hyperbaric medicine. Founded in 1967, it brings together physicians, researchers, nurses, technicians, and other professionals working in hyperbaric and diving medicine. Its membership spans clinical practice, academic research, and military medicine.

The UHMS publishes the list of approved indications for hyperbaric oxygen therapy, which forms the basis for clinical decision-making and insurance reimbursement in many settings. It maintains accreditation programmes for hyperbaric facilities, supports training and certification for hyperbaric professionals, and publishes the journal Undersea and Hyperbaric Medicine.

Position statements issued by the UHMS carry significant weight within the specialty. They represent the considered view of the organisation's leadership and membership on matters of clinical practice, safety, and professional standards. The position statement on HBO2 terminology is consistent with the UHMS's broader role in maintaining the rigour and coherence of hyperbaric medicine as a clinical discipline.

---

What This Means for the Evidence Base

The practical significance of consistent terminology becomes most apparent when examining how clinical evidence is produced and used.

Systematic reviews and meta-analyses, the highest levels of evidence in clinical medicine, depend on comprehensive and accurate literature searches. If the studies relevant to a clinical question are indexed under different terms, a review that searches only one term will miss evidence indexed under the others. The result is an incomplete picture of what the research actually shows.

This is not a hypothetical concern in hyperbaric medicine. The literature spans decades, multiple languages, and research communities with different naming conventions. A researcher working in English may use different terminology from a colleague working in French, German, or Portuguese. A study published in a diving medicine context may use different abbreviations from one published in a wound care or oncology journal.

The UHMS position statement addresses this by advocating for a single, internationally recognisable standard. HBO2, with its explicit chemical notation, is legible across languages in a way that purely alphabetic abbreviations are not. The subscript 2 is a universal chemical symbol, not a language-specific convention.

For clinicians reviewing evidence to inform treatment decisions, and for patients trying to understand what the research says about their condition, a more coherent and consistently indexed literature is a meaningful practical benefit.

---

Implications for Patients Navigating the Hyperbaric Landscape

For someone exploring hyperbaric oxygen therapy as a potential option, the terminology question has direct relevance.

The hyperbaric market includes a wide spectrum of offerings. At one end are accredited clinical facilities operating certified chambers under physician supervision, following established protocols for recognised indications. At the other end are consumer-facing products and services that use hyperbaric language loosely, often to describe low-pressure devices that do not meet the standards required for medical use.

When a patient encounters the term "hyperbaric oxygen therapy" or "HBOT" in a commercial context, it may or may not refer to the same intervention described in the clinical literature. The UHMS position statement, by advocating for HBO2 as the precise clinical term, helps create a clearer signal. Clinical and research contexts that use HBO2 are more likely to be referring to the intervention as it is defined and studied within the medical community.

This does not mean that every use of "HBOT" is misleading or that every use of "HBO2" is automatically credible. Terminology alone cannot substitute for due diligence about a facility, its equipment, its clinical oversight, and its approach to patient assessment. But consistent terminology is one of the tools that helps patients and referring clinicians navigate a landscape that is not always easy to read.

---

A Note on Regulatory and Reimbursement Contexts

Terminology also has practical implications in regulatory and reimbursement settings.

Regulatory agencies, including the Food and Drug Administration in the United States, use specific terminology when classifying devices and defining the scope of cleared indications. Insurance and reimbursement systems use specific codes and descriptors when determining coverage. When the clinical community uses inconsistent terminology, it creates friction in these processes.

A treatment described as HBO2 in a clinical guideline, HBOT in a reimbursement code, and HBO in a research paper may all refer to the same intervention, but the inconsistency requires additional interpretation at every point where these documents interact. Standardisation reduces that friction and reduces the risk of misclassification or miscommunication in administrative and regulatory contexts.

The UHMS position statement is, in this sense, a contribution not only to clinical clarity but to the operational coherence of hyperbaric medicine as a recognised and reimbursable medical specialty.

---

Conclusion

The UHMS position statement on the standardisation of HBO2 terminology is a focused document with broad implications. It addresses a specific and practical problem: the inconsistent naming of hyperbaric oxygen therapy across clinical, research, regulatory, and commercial contexts. Its recommendation, to adopt HBO2 as the standard abbreviation, is grounded in the need for precision, consistency, and a clear distinction between clinical hyperbaric medicine and the wider and less regulated hyperbaric market.

For clinicians, the statement supports a more coherent and searchable evidence base. For patients, it provides a clearer signal about what constitutes clinical hyperbaric oxygen therapy as defined and practised within the medical community. For the specialty as a whole, it reflects the UHMS's ongoing commitment to maintaining the rigour and integrity of hyperbaric medicine.

Terminology is not the most dramatic aspect of clinical medicine. But in a field where precision matters, where the evidence base is still developing, and where the commercial landscape includes significant variation in quality and safety, getting the language right is part of getting the medicine right.

---

The UHMS position statement referenced in this article is available in full as a PDF document: Standardization of the HBO2 Term. Readers are encouraged to consult the original document directly.