Key Insights On Using Hyperbaric Oxygen For Wounds

   Hyperbaric oxygen therapy (HBOT) can be a valuable adjunctive treatment for patients with various types of wounds. These expert panelists discuss their indications for HBOT, their treatment protocol and barriers to the use of HBOT.

   Q: Do you use HBOT for your wound patients and what are the indications?

   A: As Caroline E. Fife, MD, explains, hyperbaric oxygen therapy is the administration of oxygen to the entire body at atmospheric pressures greater than 1.5 times sea level pressure. She notes one should not confuse this with topical oxygen administered to part of the body or oxygen (or air) via “zip up” chambers at very low atmospheric pressures. The usual treatment pressure for wound-related problems is at least 2.0 atmospheres absolute (ATA) although she notes that sometimes patients receive pressures of 2.4 or 2.5 ATA depending on the situation. At these pressures, one can expect tissue oxygen levels in excess of 600 mmHg.

   Dr. Fife notes hypoxia is a common cause of wound healing failure. Non-healing amputations, ulcers due to vascular insufficiency and diabetic foot wounds all share the problem of tissue hypoxia, which Dr. Fife says is usually due to ischemia from vascular disease.

   She says normalizing tissue PO2 enhances resistance to infection, collagen deposition and angiogenesis. However, Dr. Fife sees a disconnect between the rationale for HBOT and what physicians can treat in terms of current Medicare coverage policy.

    “While third-party payers require us to ‘bucket’ wounds and ulcers into neat diagnostic categories, real patients rarely cooperate by falling into clear disease classification systems,” explains Dr. Fife. “A variety of problem wounds exist and are usually the result of multiple local and systemic factors.”

   Kazu Suzuki, DPM, thinks HBOT is “an invaluable adjunctive therapy in modern wound care clinics.” He notes about 10 to 15 percent of his patients who present at his wound care centers have indications for HBOT and he recommends it routinely when indicated. Dr. Suzuki works with the three HBOT centers near his wound care clinic. Two of the centers have monoplace chambers while the other has a multi-place chamber that fits about 10 people at the same time.

   Dr. Suzuki has discovered that most patients prefer monoplace chambers because of the privacy with more open appointment times. This is in contrast to multi-place chamber clinics, which have a fairly rigid schedule for treatment, according to Dr. Suzuki. If the patient is five minutes late, he or she will miss the treatment. However, he always emphasizes that the efficacy of HBOT would be the same in either size chamber, since “oxygen is oxygen” regardless of which clinic they use.

   Michael DellaCorte, DPM, CHT, uses HBOT as an advanced treatment for patients with diabetes and says he has attained “very positive” results. He combines several treatment options with HBOT. These treatment options include negative pressure wound therapy (NPWT), PICC lines, Apligraf (Organogenesis) or Dermagraft (Advanced Biohealing) along with weekly wound care and offloading.

   Q: What are the indications for HBOT? When would you incorporate HBOT into your treatment protocol?

   A: Dr. Suzuki follows the guidelines of the Undersea Hyperbaric Medical Society (UHMS, www.uhms.org). Both he and Dr. DellaCorte use HBOT for diabetic foot ulcers of Wagner grade III or higher.

   In evaluating all the randomized controlled trials (RCTs) on diabetic foot ulcers over the past 10 years, Dr. Fife says only HBOT trials have enrolled patients with Wagner III grade ulcers and/or significant tissue ischemia. She points out that all other RCTs excluded patients with ischemia.1 Accordingly, Dr. Fife says HBOT “stands alone in demonstrating benefit for ischemic diabetic foot ulcers.”

   The Centers for Medicare and Medicaid Services (CMS) cover HBOT for diabetic foot ulcers based on the RCT data.2 As Dr. Fife maintains, while there is no reason to believe that HBOT would not be equally effective for ischemic ulcers in non-diabetics, HBOT is only “covered” for Wagner III diabetic foot ulcers and not for similar limb-threatening ulcers in patients without diabetes. She also notes that HBOT is covered for acute arterial ischemia.

   Drs. Suzuki and DellaCorte will use HBOT for patients with chronic osteomyelitis. Dr. Suzuki notes the synergy among most antibiotics and HBOT, adding that he uses magnetic resonance imaging to monitor treatment progress.

   Hyperbaric oxygen is also covered for chronic refractory osteomyelitis as it increases the oxygen concentration in bone, and directly kills or inhibits the growth of organisms that prefer low oxygen concentrations, according to Dr. Fife. She notes that HBOT also augments the antibacterial effect of certain antibiotics that have an oxygen dependent transport mechanism across the bacterial cell wall. Dr. Fife says these antibiotics include aminoglycosides, vancomycin, quinolones and certain sulfonamides.3

   Drs. Suzuki and DellaCorte also use HBOT for skin flap failure. When it comes to a transmetatarsal amputation, if the plantar skin flap does not heal properly, Dr. Suzuki immediately sends the patient for HBOT for skin flap salvage. He maintains that HBOT in this situation is far better than doing another proximal amputation. Dr. DellaCorte points out that transmetatarsal amputations that start to necrose do not do well with HBOT. Emphasizing that hyperbaric oxygen is not a substitute for revascularization, Dr. DellaCorte says he will refer the patient for bypass first if appropriate for the given patient.

   Dr. Fife says HBOT can help treat compromised flaps that appear to have post-op ischemia. She adds that HBOT can also help minimize the amount of tissue that does not survive after a plastic surgical “flap” and reduce the need for repeat flap procedures.4

   Dr. Suzuki and his partner, a plastic reconstructive surgeon, use HBOT for many cancer patients who have had radiation. Unless the patient received a very short course of radiation treatment, he says most radiation recipients suffer from radionecrosis of soft tissue (burn wound of skin to internal bleeding) and bone (spontaneous fracturing of jaw bone, etc).

    “This HBOT indication is often overlooked but we have made a lot of people happy by offering this treatment option,” says Dr. Suzuki.

   In regard to protocol, Dr. Suzuki starts with the initial consultation with the hyperbaric doctor on site and then prescribes 20 sessions of HBOT for wound indications such as diabetic foot ulcers. Each session is usually 60 to 90 minutes of 2.0 to 2.8 ATA, although each clinic has its own protocols. He says patients with osteomyelitis and radionecrosis indications usually need 30 sessions or more. It is rare but when it comes to traumatic amputation of toes, Dr. Suzuki would recommend twice daily HBOT treatment for a week after re-attachment of the digit and then may reduce that to once-a-day treatment.

   Although treatment varies according to the patient condition, Dr. DellaCorte says most patients receive 90 minutes of HBOT at a pressure of 2.4 ATA for a total time of about 106 minutes in the chamber, including eight minutes to get to the appropriate pressure and eight minutes to decompress. Six weeks or 30 dives/treatments is his standard protocol. As Dr. DellaCorte notes, CMS requires re-evaluation every 10 dives/treatments. If there is no improvement, he stops treatment but treatment will continue if the wound is improving.

   Dr. Fife uses transcutaneous oximetry to screen patients with non-healing wounds to determine if spontaneous healing is possible. If TcPO2 values are low and do not increase with sea level oxygen breathing, she says patients are likely to have vascular disease. She will perform revascularization when possible and subsequently reassess the TcPO2.5

   If values continue to be low and patients have a diagnosis for which HBOT would be covered, Dr. Fife performs in-chamber TcPO2 studies. As she notes, outcome studies suggest that 84 percent of diabetic foot ulcers with in-chamber values >200 mmHg are likely to respond to HBOT. Dr. Fife says treatment can be at 2.0 ATA or greater as long as in-chamber TcPO2 values are >200 mmHg.6 Dr. Fife says it is not clear whether the same in-chamber values are predictive of success for arterial ulcers or failing flaps. The average number of treatments for a DFU is around 35, says Dr. Fife. She notes that if patients fail to demonstrate benefit after 20 treatments, then HBOT should stop.

   Q: In your experience, what is the main barrier to treatment with HBOT?

   A: Dr. Suzuki notes one contraindication is untreated pneumothorax. However, Dr. Fife adds that one can treat pneumothorax if it is vented. Dr. Suzuki asks patients to refrain from getting the treatment when they have sinus congestion as high pressure may exacerbate the symptoms. If the patient is having a hard time clearing the ears during HBOT, both he and Dr. Fife suggest putting pressure equalization tubes in the patient’s ears.

   Dr. DellaCorte adds that ear barotrauma due to chamber pressure and claustrophobia are other barriers to treatment. Dr. Fife notes another relative contraindication includes pulmonary air trapping (chronic obstructive pulmonary disease). Patients with COPD are at risk for pulmonary barotrauma and Dr. Fife says one must decide whether it is safe for these patients to undergo HBOT. Patients with uncontrolled seizures are not recommended for HBOT, according to Dr. Fife.

   Dr. Suzuki’s patients sometimes complain of logistical problems since the ideal HBOT occurs Monday through Friday for 20 days, meaning four weeks of commitment. For out-of-town patients (commuting for an hour or longer) or dialysis patients, he recommends treatment three times a week (on non-dialysis days). Outcome data suggest that regular attendance to therapy affects whether patients benefit, according to Dr. Fife.7 She adds that therapy five days per week can be difficult for chronically ill patients.

   Dr. Suzuki refutes the claim that patients on VAC therapy (KCI) cannot be in the chamber. He says as long as the HBOT technicians know how to disconnect and reconnect the suction hose to keep the machine outside of the chamber, patients using VAC therapy can successfully undergo treatment with HBOT.

   Drs. DellaCorte and Fife note the barrier of insurance coverage. Although it is likely that non-diabetic patients with ischemia would benefit, Dr. Fife says in the absence of acute arterial insufficiency, a failing flap or osteomyelitis, patients whose only diagnosis is chronic arterial disease do not meet current coverage guidelines.

    “This is unfortunate since there are no other interventions likely to prevent limb loss if revascularization has failed to sufficiently increase tissue oxygen levels,” explains Dr. Fife.

   Research has shown that HBOT is cost effective in comparison to amputation and increases quality of life years.8,9 Dr. Fife notes the cost benefit of HBOT is enhanced by proper patient selection. Patients are best referred before tissue loss has progressed to the point where amputation is inevitable, says Dr. Fife. She notes that transcutaneous oximetry can be useful in screening out patients who are likely to get well without HBOT or patients who cannot be helped.

   Dr. Fife says one should not use HBOT as an alternative to proper revascularization. She says those on dialysis or those who have a transplant are less likely to benefit from HBOT, but are also less likely to benefit from any other intervention.

   Dr. Fife maintains that HBOT must be under the supervision of a properly trained advanced care practitioner who can manage complications.

    “When hyperbaric treatment is used in conjunction with standard wound care, researchers have demonstrated improved results in the healing of difficult or limb-threatening wounds in comparison to routine wound care alone,” she says.

Dr. DellaCorte is a Certified Hyperbaric Technologist. He is also a Fellow of the American College of Foot and Ankle Surgeons, and a Fellow of the American College of Foot and Ankle Orthopedics and Medicine. He is in private practice in Maspeth, N.Y.
Dr. Fife is an Associate Professor in the Department of Internal Medicine, Division of Cardiology at the University of Texas Health Science Center in Houston. She is the Director of Clinical Research at the Memorial Hermann Center for Wound Healing and Hyperbaric Medicine.

Dr. Suzuki is the Medical Director of Tower Wound Care Center at the Cedars-Sinai Medical Towers. He is also on the medical staff of the Cedars-Sinai Medical Center in Los Angeles and is a Visiting Professor at the Tokyo Medical and Dental University in Tokyo, Japan.

References:

1. Carter MJ, Fife CE, Walker D, Thomson B. Estimating the applicability of wound-care randomized controlled trials to general wound care populations by estimating the percentage of individuals excluded from a typical wound care population in such trials. Adv Skin Wound Care 2009; 22(1):316-24. 2. Faglia E, Favales F, Aldeghi A, et al. Adjunctive systemic hyperbaric oxygen therapy in treatment of severe prevalently ischemic diabetic foot ulcer. Diabetes Care 1996;19(12):1338-1343. 3. Mader JT, Shirtliff ME, Calhoun JH. The use of hyperbaric oxygen in the treatment of osteomyelitis. In: Hyperbaric medicine practice. Best Publishing Co., Flagstaff, Arizona, 1999, pp. 603-616. 4. Zamboni WA. Applications of hyperbaric oxygen therapy in plastic surgery. In: Oriani G, Marroni A, Wattel F, eds. Handbook on hyperbaric oxygen therapy. Springer-Verlag, New York, 1996. 5. Fife CE, Smart DR, Sheffield PJ, Hopf HW, Hawkins G, Clarke D. Transcutaneous oximetry in clinical practice: consensus statements from an expert panel based on evidence. Undersea Hyperb Med 2009; 36(1):43-53. 6. Fife CE, Buyukcakir C, Otto GH, Sheffield PJ, Warriner RA, Love TL, Mader J. The predictive value of transcutaneous oxygen tension measurement in diabetic lower extremity ulcers treated with hyperbaric oxygen therapy; a retrospective analysis of 1144 patients. Wound Rep Regen 2002; 10(4):198-207. 7. Fife CE, Buyukcakir C, Warriner R, Sheffield P, Love T, Otto G. Factors influencing the outcome of lower extremity of diabetic ulcers treated with hyperbaric oxygen therapy. Wound Repair Regen 2007; 15(3):322-331. 8. Cianci P, Petrone G, Drager S, Lueders H, Lee H, Shapiro R. Salvage of the problem wound and potential amputation with wound care and adjunctive hyperbaric oxygen therapy: an economic analysis. J Hyperbaric Med 1988; 3:127-141. 9. Guo S, et al. Cost effectiveness of adjunctive hyperbaric oxygen in the treatment of diabetic ulcers. Int J Technol Assess Health 2003; 19(4):731-737.