A clinical practice guideline for the use of hyperbaric oxygen therapy in the treatment of diabetic foot ulcers

BACKGROUND: The role of hyperbaric oxygen (HBO2) for the treatment of diabetic foot ulcers (DFUs) has been examined in the medical literature for decades. There are more systematic reviews of the HBO2/DFU literature than there have been randomized controlled trials (RCTs), but none of these reviews has resulted in a clinical practice guideline (CPG) that clinicians, patients and policy-makers can use to guide decision-making in everyday practice. METHODS: The Undersea and Hyperbaric Medical Society (UHMS), following the methodology of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) Working Group, undertook this systematic review of the HBO2 literature in order to rate the quality of evidence and generate practice recommendations for the treatment of DFUs. We selected four clinical questions for review regarding the role of HBO2 in the treatment of DFUs and analyzed the literature using patient populations based on Wagner wound classification and age of the wound (i.e., acute post-operative wound vs. non-healing wound of 30 or more days). Major amputation and incomplete healing were selected as critical outcomes of interest. RESULTS: This analysis showed that HBO2 is beneficial in preventing amputation and promoting complete healing in patients with Wagner Grade 3 or greater DFUs who have just undergone surgical debridement of the foot as well as in patients with Wagner Grade 3 or greater DFUs that have shown no significant improvement after 30 or more days of treatment. In patients with Wagner Grade 2 or lower DFUs, there was inadequate evidence to justify the use of HBO2 as an adjunctive treatment. CONCLUSIONS: Clinicians, patients, and policy-makers should engage in shared decision-making and consider HBO2 as an adjunctive treatment of DFUs that fit the criteria outlined in this guideline. The current body of evidence provides a moderate level of evidence supporting the use of HBO2 for DFUs. Future research should be directed at improving methods for patient selection, testing various treatment protocols and improving our confidence in the existing estimates.(AU)

Gender differences in human skeletal muscle and subcutaneous tissue gases under ambient and hyperbaric oxygen conditions.

OBJECTIVES: The purpose of this study is to ascertain if gender differences exist in human skeletal muscle (MM) and subcutaneous (SC) tissue gases using monoplace and multiplace hyperbaric oxygen (HBO2) treatment protocols. METHODS: Gas tensions in resting MM and SQ tissues were recorded at 4-minute intervals using two protocols: The 150 minute monoplace HBO2 chamber protocol utilized continuous oxygen (O2) breathing at 202.6 kPa, that is 2 atmospheres absolute (2 ATA). The multiplace HBO2 chamber protocol had four 5-minute air breaks between five 20 minute O2 breathing periods at 2 ATA and took 180 minutes to complete. Tissue gas samples were obtained by the vacuum technique through a low permeable Teflon membrane and analyzed using a mass spectrometer. RESULTS: Over 40,000 individual step analyses showed gas tensions changed (repeated measures of variance, p = 0.00001) with time as the gas pressures and mixtures breathed were altered. Statistically significant differences between males and females in loading and unloading of SC nitrogen (N2) (P = 0.0001), SC O2 (P = 0.001) and MM O2 (P = 0.003) were observed in the multiplace protocol. Females release SC N2 more slowly; while increasing their MM and SC O2 tensions higher than males. Muscle and SC CO2 levels decrease in both males and females when exposed to HBO2 and increase when breathing air. CONCLUSIONS: Three main gender differences are observed in tissue gas loading and unloading under hyperbaric oxygen exposures: Females release SC N2 more slowly and saturate MM O2 and SC O2 to greater extents. Finally, female MM and SC O2 rose to higher levels in the multiplace protocol than in the monoplace protocol, which was not observed in the male subjects. This information may help explain why males and females respond differently to diving decompression stresses and the clinical application of HBO2.

Diving medicine: contemporary topics and their controversies.

SCUBA diving is a popular recreational sport. Although serious injuries occur infrequently, when they do knowledge of diving medicine and/or where to obtain appropriate consultation is essential. The emergency physician is likely to be the first physician contact the injured diver has. We discuss 8 subjects in diving medicine which are contemporary, yet may have controversies associated with them. From this information the physician dealing primarily with the injured diver will have a basis for understanding and managing, as well as where to find additional help, for his/her patients' diving injuries.

Cigarette smoking and transcutaneous oxygen tensions: a case report.

We report the effects of acute smoking cessation on transcutaneous oxygen (PtcO2) measurements in room air and with hyperbaric oxygen (HBO2) of an extremity at risk for amputation. The reports on cigarette smoking and PtcO2 do not discuss acute smoking cessation. PtcO2 measured 46 h after smoking cessation increased 10% while breathing room air and 34% with HBO2, as compared to measurements made before smoking cessation.

Hyperbaric oxygen therapy for acute smoke inhalation injuries.

Hyperbaric oxygen therapy is an important adjunct in the management of respiratory injuries secondary to smoke inhalation, especially when injury is complicated by inhalation of a toxic chemical such as carbon monoxide or cyanide. For carbon monoxide poisoning, such therapy has become a standard of practice. As more information becomes available concerning the ability of hyperbaric oxygen to reduce reperfusion injuries, we anticipate that this therapy will become a standard of practice for managing smoke inhalation injuries and cyanide poisoning as well.

Hyperbaric oxygen reduces edema and necrosis of skeletal muscle in compartment syndromes associated with hemorrhagic hypotension.

This study examined the effect of exposures to hyperbaric oxygen on the development of the edema and necrosis of muscle that are associated with compartment syndromes that are complicated by hemorrhagic hypotension. A compartment syndrome (twenty millimeters of mercury for six hours) was induced by infusion of autologous plasma in the anterolateral compartment of the left hind limb of seven anesthetized dogs while the mean arterial blood pressure was maintained at sixty-five millimeters of mercury after 30 per cent loss of blood volume. These dogs were treated with hyperbaric oxygen (two atmospheres of pure oxygen) and were compared with six dogs that had an identical compartment syndrome and hypotensive condition but were not exposed to hyperbaric oxygen. Forty-eight hours later, edema was quantified by measuring the weights of the muscles (the pressurized muscle compared with the contralateral muscle), and necrosis of muscle was evaluated by measuring the uptake of technetium-99m stannous pyrophosphate. The ratio for edema was significantly (p = 0.01) greater in dogs that had not been exposed to hyperbaric oxygen (1.15 +/- 0.01) than in the dogs that had been treated with hyperbaric oxygen (1.01 +/- 0.03), and the ratio for necrosis of muscle was also significantly (p = 0.04) greater in dogs that had not had hyperbaric oxygen (1.96 +/- 0.41) than in those that had been treated with hyperbaric oxygen (1.05 +/- 0.11). Comparisons were also made with the muscles of four normal control dogs and separately with the muscles of six normotensive dogs that had an identical compartment syndrome and normal blood pressure and were not treated with hyperbaric oxygen.(ABSTRACT TRUNCATED AT 250 WORDS)

Delayed use of hyperbaric oxygen for treatment of a model anterior compartment syndrome.

This study examines the effect of delayed exposure to hyperbaric oxygen on muscle necrosis and edema development following compartment syndromes in the canine hindlimb. Compartment syndromes (100 mm Hg for 8 h) were generated in one anterolateral compartment of six anesthetized dogs. After a 2-h delay, three 1-h hyperbaric oxygen treatments (2 atm absolute pure oxygen) were given during the next 12 h. Two days later, technetium-99m stannous pyrophosphate (99mTc Sn-PYP) was injected intravenously; 3 h later, samples were obtained from the pressurized and contralateral control muscles, weighed for edema development, counted for 99mTC Sn-PYP uptake, and evaluated histologically. Hyperbaric oxygen treatments, even when delayed 2 h, reduced muscle necrosis and intramuscular edema to negligible levels (p less than 0.05) compared with untreated animals. In addition, muscle morphology remained essentially normal in all hyperbaric oxygen-treated animals. We conclude that even if hyperbaric oxygen treatments are delayed 2 h, edema and muscle necrosis are reduced significantly in a model compartment syndrome.

The role of hyperbaric oxygen in the management of Fournier's gangrene.

Fournier's gangrene of the external genitals is a complex entity characterized by acute onset, rapid progress to gangrene, toxemia and high mortality rate. The disease may be primary as described by Fournier or secondary with a detectable cause in the colo-rectal area, the lower urogenital tract or in the perineum. The disease may affect healthy young males (originally described by Fournier) or elderly subjects especially with general ill health, cancer, diabetes, liver or renal failure, immunosuppression, etc. The microbiology is as complex as the etiology. The nosiology is likewise complex. Because the mortality is high, it is important to be aggressive in therapy. Triple attack is necessary, viz.: antibiotic coverage for aerobes and anaerobes, general supportive measures and adequate surgical debridement. We, recommend Hyperbaric Oxygen Therapy (HBO) treatment in specialized centers as an adjunctive measure since we had no mortality in the cases we treated. In expert centers, HBO has very few complications which are outweighed by the benefit the patient gets. The one-man chamber is the commonest in use, but for a compromised patient the multiplace may be more appropriate. In the very early stage, HBO may avert gangrene or reduce it. It is important to have a high index of awareness of this disease amongst the medical profession. More work is needed for the more precise definition, classification and management of the complex syndrome of Fournier.

Treatment of smoke inhalation by hyperbaric oxygen.

Five patients with smoke inhalation from house fires presented to the hospital in a comatose state. Carboxyhemoglobin levels were elevated in all five patients, mean=32% +/- 6. Arterial blood gases revealed the following means: pH 7.16 +/- 0.06; PCO2 35 mm HG +/- 10.5; HCO3 12.6 mEq/L +/- 0.07; base excess -16 mEq/L +/- 1.58; PO2 353 mm Hg +/- 149; O2 saturation 66% +/- 5.5. The patients were presumed to have both cyanide and carbon monoxide intoxication and were treated with the cyanide antidote kit and hyperbaric oxygen (HBO). Four of five patients awoke within 15 minutes of reaching maximum pressure and remained neurologically intact thereafter. The fifth patient died one week later. Cyanide blood levels drawn prior to treatment revealed a mean of 1.62 microgram/mL +/- 1.44. The highest cyanide level was 3.9 microgram/mL (the death) and the lowest 0.35 microgram/mL. We conclude that smoke inhalation can result in acute cyanide poisoning and that hyperbaric oxygen is a useful adjunct in the treatment of smoke inhalation.

Osteomyelitis in the spinal cord injured: a review and a preliminary report on the use of hyperbaric oxygen therapy.

Spinal Cord Injury patients are liable to develop osteomyelitis mostly by extension from pressure ulcers. In 2055 records reviewed in the Long Beach Spinal Cord Injury Service of the Veterans Administration Medical Center, the incidence was found to be 4.3 per cent. Of these osteomyelitis developed secondary to pressure ulcers in 88 per cent, the rest developed as a result of trauma and/or surgery. Forty-four patients manifesting chronic osteomyelitis were treated in a monoplace hyperbaric oxygen (HBO) chamber, in addition to receiving antibiotic and surgical treatment. HBO was found useful as an adjunct to help to resolve the bone infection and encourage wound healing. Two-thirds of the patients were cured, and the follow-up was from 6 months to 9 years. We believe that HBO is a useful adjunctive therapeutic measure in the management of chronic osteomyelitis in the spinal cord injured and in the prevention of its complications.

Gas gangrene.

Gas gangrene is not a disease of the past. Despite improved awareness, earlier care of trauma victims, new antibiotics, and advanced monitoring techniques, histotoxic clostridia continue to cause loss of life and limb. A 20-year literature review on gas gangrene (Part I) indicates that a combined therapy approach with early recognition, surgical intervention, appropriate antibiotics, and hyperbaric oxygen (HBO) provides optimal care. Part II, a 15-year clinical experience, appears to be the largest English-language series reported using the combined therapy of antibiotics, surgery, and hyperbaric oxygen. One hundred thirty-nine patients (95 males and 44 females), average age, 38 years, were admitted with clostridial myonecrosis. Sixty-seven were in shock at admission and the 27 deaths occurred in this group. One hundred twelve patients (81%) survived the infection. There was a 5% mortality in post-traumatic extremity clostridial myonecrosis. Age and concurrent disease increased the mortality rate, as did delay from time of diagnosis to aggressive combined treatment.