Is Hyperbaric Oxygen Therapy Effective?
by Thomas E. Serena MD, FACS, FACHM, FAPWCA
Parents of most children growing up in the sixties read them Winnie the Pooh. My father, a Woodrow Wilson fellow in English literature, read us Homer’s Odyssey, four times. I remember listening with excitement and anticipation as Odysseus rowed between the fearsome sea monsters Scylla and Charybdis. More than 40 years later I find myself navigating two equally challenging concepts: Efficacy and Effectiveness.
In research, efficacy denotes the performance of a treatment modality, such as a medication, a device or therapy, in the precise well-ordered setting of a randomized controlled clinical trial (RCT). RCTs represent the gold-standard for judging a product's usefulness. Effectiveness, on the other hand, reflects the value of a therapy in the less controlled, "real world" setting of everyday practice. Studies examining effectiveness typically follow RCTs to determine how well a treatment translates from clinical trials which limit enrollment to a highly selective group of subjects, to the broader more heterogeneous patient population as a whole.
A disparity between efficacy and effectiveness could mean that the treatment is not generalizable to all of the patient’s with a given disease. However, a discrepancy could also arise if physicians prescribing the modality do not have the appropriate training or requisite skill level needed to obtain results in clinical practice equal to those seen in the RCTs. This latter explanation has been the driving force behind medical specialization: the advent of an innovative technology requires physicians with specialized knowledge and skill to deliver it; conversely, in the hands of less skilled physicians the modality is not as effective.
Four separate clinical trials established the efficacy of hyperbaric oxygen therapy (HBOT) in the treatment of diabetic foot ulcers. Taken together, the studies demonstrated an accelerated healing time and decreased amputation rates; however, until recently the effectiveness of HBOT had not been examined. In February of this year Margolis and colleagues published a retrospective analysis of more than 6,000 patients with diabetic foot ulcers treated at centers under contract with one of the largest management companies in the United States (National Healing now Healogics, Jacksonville, FL).1 The authors concluded that HBOT did not improve the time to healing or reduce the rate of amputation for the patients treated at these centers. Clearly, the study has a number of serious design and statistical flaws that render its conclusions questionable. I will leave that argument to the statisticians and epidemiologists.
Let us assume for the moment that the conclusions set forth in this retrospective are correct: HBOT, a demonstrably efficacious treatment was not shown to be effective in this study. The most plausible explanation for the findings is that HBOT was not utilized appropriately by the treating physicians. The majority of clinicians in the referenced cases belonged to a large physician panel. As such, they worked in the wound clinics for blocks of time as little as four hours per week: HBOT was not prescribed by full-time specialists dedicated to wound and hyperbaric medicine. On the contrary, it was provided by "dabblers": part-time physicians administering itinerant care. It is not surprising then that the outcomes fell short of the clinical trial results.
This study provides further support for what I have being saying for years: wound care must develop into a specialty with actual specialists. We must develop training programs and work toward ASGME approved physician board certification in wound care. In the interim, hospitals might consider staffing their wound centers with dedicated "woundologists" rather than itinerant "dabblers."
Finally, one of the inherent dangers in disseminating the results of a flawed retrospective study of the results from a single entrepreneurial entity reveals more about that entity than it does about the efficacy of HBOT; and, clearly, draws unwarranted attention from Centers for Medicare Services (CMS). It is not beyond the realm of possibility that CMS could suspend HBOT coverage for diabetic foot ulcers (DFU) pending further study on its effectiveness. This would eliminate a valuable weapon in the fight against major amputations in patients with diabetes. Those of us "woundologists" treating actual patients day-in-day-out know with a certainty that the last best hope for our DFU patients is HBOT. We've seen it; we've lived it. There is an old bromide that has purchase here: "A man with an argument is no match for a man with an experience."
The solution lies in in the creation of true centers of excellence. When other specialties, such as bariatric surgery, faced similar challenges the COE designation demanded that only well trained specialists with documented skills could provide care. COE accreditation for wound and hyperbaric centers would require hospitals and or management companies to staff their clinics with full-time woundologists. Only centers with COE designation would be permitted to bill CMS for wound and hyperbaric services.
1. Margolis DJ, Gupta J, Hoffstad O, et. al. Lack of effectiveness of hyperbaric oxygen therapy for the treatment of diabetic foot ulcers and prevention of amputation. Diabetes Care 2013 Feb 19. (Epub ahead of print).
About The Author
Dr. Thomas Serena has published more than 75 peer-reviewed papers and has made in excess of 200 presentations worldwide. He has been elected to the Board of Directors of both The Wound Healing Society and the American College of Hyperbaric Medicine (ACHM), the leading academic society in the field of Hyperbaric Medicine. In 2013 Dr. Serena was elected vice president of the American Professional Wound Care Association (APWCA). Dr. Serena has opened and operates Wound Care and hyperbaric oxygen treatment clinics across the United States.
The views and opinions expressed in this blog are solely those of the author, and do not represent the views of WoundSource, Kestrel Health Information, Inc., its affiliates, or subsidiary companies.