While there is not an overwhelming amount of literature on hyperbaric oxygen therapy (HBO), the recent decision by the Centers for Medicare and Medicaid Services (CMS) to cover the use of HBO in treating diabetic foot wounds has fueled new discussions on the potential efficacy of the modality. With this in mind, our panelists discuss their experiences in using HBO, the current literature on the subject and reimbursement issues.
Q: What has been your experience in using hyperbaric oxygen therapy (HBO) to treat lower extremity wounds?
A: Leon Brill, DPM, says he has had a “very positive” experience using HBO within his group practice setting. Dr. Brill was involved in a 33-month retrospective study of patients with diabetic foot ulcers. He says this study consisted of 87 patients who received HBO in addition to standard wound care and 382 patients who received only standard wound care. Dr. Brill notes the limb salvage rate for the HBO patients was 72 percent in comparison to the 53 percent salvage rate for those who received standard wound care.
Steven Kominsky, DPM, who has used HBO in 100 cases over a 20-year period, says he has been pleased with the results he has seen.
“Many ‘non-salvageable’ extremities have healed with the use of hyperbaric oxygen and meticulous wound care,” notes Dr. Kominsky.
Ronald Sage, DPM, says he has had limited experience with the modality as he has only used HBO to treat five or six patients with diabetes over the past 10 years. These patients had Wagner Grade III foot ulcers, severe peripheral vascular disease and long-term non-healing. Dr. Sage says half of the patients had successful healing with HBO while the other half went on to amputation.
Drs. Brill and Kominsky agree that appropriate patient selection is the key to success in using HBO. Dr. Brill emphasizes that he reserves the modality for a select group of patients whom he feels are at a high risk of limb loss. These patients include those who have necrotizing fasciitis, chronic osteomyelitis and threatened flaps from various types of amputations as well as peripheral vascular disease cases that are not reconstructable.
When the patient’s pulses are strong and he or she has a well-perfused limb, HBO is unnecessary, according to Dr. Kominsky. He has found that HBO is most effective for treating those who have marginal circulation. Dr. Kominsky adds that obtaining non-invasive vascular studies, including transcutaneous oxygen measurements, can help you determine the patient’s healing potential.
When it comes to HBO, David Armstrong, DPM, says he has seen the best outcomes when he has used it as an antibiotic after performing emergent debridement of a severe limb- or life-threatening infection. In his experience, Dr. Armstrong has found that eight to 10 dives of HBO over a four to five-day period has appeared to be beneficial.
Dr. Sage says HBO treatments are typically performed for 90 minutes a day for approximately 30 days, depending upon the patient’s progress. He notes that he reserves HBO for patients with significant peripheral vascular disease who have failed four to six weeks of standard wound care and had an unsuccessful bypass or are not bypass candidates.
Dr. Armstrong also notes that he has generally used HBO to help treat patients who have severe peripheral occlusive disease but are not bypass candidates. However, Dr. Armstrong notes, that “for my health care dollar, I often prefer a distal bypass for a bypass candidate rather than a six-week course of HBO, if at all possible.”
Q: Are there any prospective pivotal studies that prove HBO is more effective than placebo?
A: Dr. Brill says there are no pivotal studies that demonstrate the efficacy of HBO. Having conducted a prospective trial on HBO, Dr. Brill points out that it is a “very difficult” process and difficulties in trial design have contributed to the lack of pivotal evidence on this modality.
However, Dr. Brill says there is compelling evidence that HBO does have a beneficial effect. Last year. Medicare published a decision memorandum regarding the coverage of HBO and Dr. Brill says this document provides a good synopsis of the HBO studies that have been conducted so far. However, he does caution that there are major flaws such as comparability of patients, treatment bias and the inability to adequately blind the studies.
There are numerous anecdotal and retrospective studies that support using hyperbaric oxygen in problem wounds, according to Dr. Sage. He says these studies are nicely summarized on www.hyperbaricmedicine.org , the Web site of the American College of Hyperbaric Medicine.
Dr. Armstrong says he is not certain if there are any good, evidence-based or even anecdotally-based protocols that would drive one to use or not use HBO. However, he does cite a few intriguing studies. Kalani, et. al., from the Karolinska Institute in Sweden, presented a small randomized, controlled trial of 38 patients. Dr. Armstrong says this study suggested that using 40 to 60 dives of HBO per patient appeared to accelerate healing and lower the prevalence of amputations in a three-year follow-up.
According to Dr. Sage, Faglia, et. al., may have done the best study to date of using HBO in Wagner Grade III ulcers with their 1996 study published in Diabetes Care. The study was comprised of 35 patients who had standard wound care and 33 patients who received HBO. Dr. Sage says the amputation rate was 100 percent in the standard care group whereas the HBO group had a 25 percent amputation rate.
However, Dr. Armstrong says studies, such as the one by Faglia, et. al., have been “fatally flawed” in one way or another. Dr. Armstrong points out that, in Faglia’s study, far more people in the HBO group received lower-extremity bypasses than in the non-HBO group, rendering the data less than helpful.
While the study may be flawed, Dr. Sage says it was considered to be “pivotal” in the recent decision by the CMS to reimburse hyperbaric oxygen therapy for diabetic ulcers, according to the American College of Hyperbaric Medicine.
While Dr. Armstrong notes there is a physiologic rationale for why HBO should work, he says “translating that into viable indications has been problematic for many.”
Q: What are the current reimbursement issues in regard to insurance companies and Medicare paying for this modality?
A: HBO is a reimbursable procedure under Medicare, according to Drs. Kominsky and Sage. (Editor’s Note: For further info, see “CMS Expands Coverage Of HBO To Diabetic Foot Ulcers,” News & Trends, April issue.) Dr. Kominsky says HBO is also reimbursable under many of the managed care plans as well. Dr. Kominsky does caution that pre-authorization is necessary in some instances. He also points out that some third-party carriers limit the number of dives. In these cases, Dr. Kominsky says you may need to provide photo documentation in order to continue using the therapy to wound closure.
Dr. Armstrong has heard that recent Medicare findings are very promising in terms of funding this type of therapy. However, he does express concern that when facilities invest in the chambers, there may be an accompanying pressure to use the therapy on patients who may or may not have the appropriate indications.
“Frequently, the decision by an HBO specialist is ‘Let’s give it a try and see how it works,’” explains Dr. Armstrong. “Unfortunately, giving HBO a try is a bit more expensive than modifying an offloading modality or using a different dressing. I will admit this is changing, but it’s not changing fast enough or in enough centers to satisfy many skeptical physicians.”
Q: What complications have you seen in using systemic HBO?
A: Drs. Armstrong and Brill say claustrophobia is the most common sequela. Dr. Brill says claustrophobia cases can be resolved by providing adequate sedation for the patient. He notes that some patients have had trouble clearing their ears when the chamber is going to depth, but Dr. Brill says this can be alleviated with nasal decongestants or via a myringotomy in troublesome cases.
Dr. Armstrong adds that he has had patients who had perforated eardrums after undergoing HBO therapy, but says these incidents were his fault and that they could have been prevented with better evaluation along with his colleagues in ear, nose and throat and/or prophylaxis of the patients beforehand.
Certain ear problems, cardiac and pulmonary conditions may be affected by HBO treatment, notes Dr. Sage. Accordingly, he emphasizes that hyperbaric care should be supervised by a physician who is experienced in using this modality. Dr. Sage also recommends that DPMs continue to provide optimal wound care and monitor the progress of the wound during HBO therapy.
While Dr. Kominsky hasn’t see any complications per se, he has seen a few non-healing wounds. He says patients who have not benefited from HBO therapy have either had an underlying undiagnosed infection (usually osteomyelitis that wasn’t seen on X-ray) or were poorly perfused. Dr. Kominsky says this goes back to the importance of appropriate patient selection.
“I have learned through experience with a large patient pool that there must be some blood flow to the foot in order for (HBO) to be an effective tool,” notes Dr. Kominsky.
Dr. Armstrong is the Director of Research and Education within the Department of Surgery, Podiatry Section, within the Southern Arizona Veterans Affairs Medical Center in Tuscon, Ariz. He is a member of the National Board of Directors of the American Diabetes Association.
Dr. Brill practices at the Limb Salvage Centre at the BrillStone Building and is President of the BrillStone Corporation in Dallas. He is also a Consultant in wound care and reconstructive foot and ankle surgery at the Wound Care Clinic at Presbyterian Hospital in Dallas.
Dr. Kominsky is Residency Director and Director of Podiatric Medical Education at Washington Hospital Center in Washington, D.C. He is a Fellow of the American College of Foot and Ankle Surgeons and Diplomate of the American Board of Podiatric Surgery.
Dr. Sage is a Professor and Chief of the Section of Podiatry within the Department of Orthopaedic Surgery and Rehabilitation at the Stritch School of Medicine at Loyola University.
Dr. Karlock (pictured) is a Fellow of the American College of Foot and Ankle Surgeons, and practices in Austintown, Ohio. He is a member of the Editorial Advisory Board for WOUNDS, A Compendium of Clinical Research and Practice.