The Physicians and Researchers Shaping HBOT Worldwide

Hyperbaric oxygen therapy has a longer clinical history than most people realise. It has been used in formal medical settings since the 1960s, and the body of research supporting its established applications, wound healing, decompression sickness, carbon monoxide poisoning, radiation injury, is substantial. But the field has also been shaped by a smaller group of clinicians and researchers who have pushed into less established territory: traumatic brain injury, post-stroke recovery, PTSD, long COVID, and cognitive decline.

Understanding who those researchers are, what they have contributed, and where their work is most credible is useful context for anyone navigating HBOT seriously, whether as a patient, a referring physician, or a family member trying to make sense of conflicting information.

This article profiles the physicians and researchers who have most significantly shaped the field globally.

Israel: The Sagol Center and Professor Shai Efrati

No single figure has done more to advance the evidence base for HBOT in neurological applications than Professor Shai Efrati, Director of the Sagol Center for Hyperbaric Medicine and Research at Shamir Medical Center in Israel.

Efrati's work has focused on what he terms neuroplasticity induction, the hypothesis that HBOT can stimulate repair and regeneration in brain tissue that has been damaged but not destroyed. His research group has published randomised controlled trials on HBOT in post-stroke patients, traumatic brain injury, fibromyalgia, and age-related cognitive decline, as well as the landmark 2022 trial on HBOT in long COVID.

The Sagol Center is the largest hyperbaric facility in the world dedicated to research, with over 60 chambers and a clinical research programme that has produced more peer-reviewed publications on HBOT in neurological conditions than any other institution. Efrati's work is not without its critics, some researchers have questioned aspects of his trial methodology and the breadth of claims made, but his contribution to the evidence base is undeniable.

His 2023 trial on HBOT in treatment-resistant PTSD, published in PLOS ONE, is among the most rigorous studies in the field and has attracted significant attention from military medicine communities in the United States and Israel.

United States: Dr Paul Harch

Dr Paul Harch, Clinical Professor of Medicine at Louisiana State University Health Sciences Center, is one of the longest-serving and most prolific researchers in hyperbaric medicine in the United States. His work spans more than three decades and has focused particularly on traumatic brain injury, chronic traumatic encephalopathy (CTE), and neurological applications of HBOT.

Harch is the author of the book The Oxygen Revolution and has been a consistent advocate for expanding the clinical recognition of HBOT in TBI. His case series and small trials on HBOT in veterans with blast-induced TBI have been influential in bringing the treatment to the attention of military medicine, even as the evidence base remains contested in some quarters.

He has also contributed to the foundational understanding of HBOT dosing, the relationship between pressure, oxygen concentration, session duration, and biological effect, which is relevant to understanding why protocols vary so significantly between facilities and conditions.

United States: Dr William Duncan and the Undersea and Hyperbaric Medical Society

The Undersea and Hyperbaric Medical Society (UHMS) is the primary professional body governing hyperbaric medicine in the United States and internationally. Its evidence review process determines which indications receive formal approval for reimbursement and clinical use.

The UHMS currently recognises 14 approved indications for HBOT, including diabetic foot ulcers, radiation injury, carbon monoxide poisoning, and decompression sickness. Its approval process is rigorous and conservative, which is appropriate for a medical intervention, but has also meant that conditions with emerging evidence, including TBI and neurological applications, remain outside formal approval despite a growing body of research.

Understanding the UHMS framework is important for anyone navigating HBOT access, particularly in the United States, where insurance coverage is tied to approved indications.

The Asia-Pacific Region: Professor David Smart

Professor David Smart, Director of Hyperbaric Medicine at Royal Hobart Hospital, is one of the most prominent hyperbaric physicians and researchers in the Asia-Pacific region. His work has spanned emergency hyperbaric medicine, diving medicine, and the clinical application of HBOT in wound care and radiation injury.

Smart has contributed to the international evidence base through clinical trials and systematic reviews, and has been involved in training and credentialling programmes for hyperbaric physicians across the region. The Royal Hobart Hospital hyperbaric unit is one of the most active research centres in the southern hemisphere.

The hyperbaric medicine community across the Asia-Pacific is relatively small but well-organised, with formal training pathways and a network of hospital-based hyperbaric units operating to recognised international standards.

Europe: Professor Zeljko Dujic and the Split Research Group

Professor Zeljko Dujic at the University of Split School of Medicine in Croatia has led one of Europe's most productive hyperbaric research programmes, with a particular focus on the physiology of decompression, cardiovascular responses to hyperbaric exposure, and the mechanisms by which HBOT affects vascular function.

While his work is more mechanistic than clinical, it has contributed significantly to the understanding of how HBOT produces its effects at a physiological level, knowledge that underpins the rationale for its use in conditions involving vascular insufficiency and tissue hypoxia.

The Emerging Longevity Medicine Research Stream

A newer strand of HBOT research has emerged from the longevity medicine community, where researchers are investigating whether HBOT can slow or reverse aspects of cellular ageing. Efrati's group at the Sagol Center published a study in 2020 in Aging showing that a protocol of 60 HBOT sessions produced significant lengthening of telomeres and reduction in senescent cells in healthy older adults, findings that attracted considerable attention and some scepticism.

This research is preliminary and the clinical implications are not yet clear. But it has brought HBOT to the attention of a new audience, high-performance individuals and longevity-focused clinicians, and is driving investment in premium HBOT facilities internationally.

What This Means for Patients and Referring Physicians

The HBOT field is not monolithic. It encompasses a well-established core of approved indications with strong evidence, a growing body of research in neurological and post-viral applications, and an emerging strand of longevity medicine research that is earlier in its development.

The researchers profiled here represent the most credible contributors to each of these streams. When evaluating claims made by HBOT facilities or practitioners, understanding whether those claims are grounded in the work of researchers like Efrati, Harch, or Smart, or whether they are extrapolations from that work, or something else entirely, is a useful filter.

For patients seeking HBOT outside their home country, or for referring physicians trying to identify facilities that operate to a clinical standard, the connection between a facility's protocols and the published research is one of the most important things to assess.