Adjunctive hyperbaric oxygen for the treatment of diabetic foot wounds resulted in a reduction in the rate of major amputation required to control infection.

Clinical Bottom Line: 1. The addition of hyperbaric oxygen to the treatment regimen for diabetic foot wounds resulted in a lower rate of major amputation. Appraised by: Mike Bennett and Simon Mitchell, Australia and New Zealand Hyperbaric Medicine Group, c/o ANZCA, St. Kilda Rd Melbourne; Friday, 16 April 1999

Clinical Scenario: A patient presented for management of a diabetic foot ulcer and we wondered if the addition of hyperbaric oxygen would increase the chance of healing. Three-part Question: In patients with diabetic foot wounds, does the addition of hyperbaric oxygen therapy to a standard treatment regimen result in any improvement in wound healing, or reduction in amputation rate? Search Terms: Diabetic foot

The Study: Non-blinded randomised controlled trial with intention-to-treat. Patients with chronic diabetic foot lesions (average duration 10 years) admitted for multi-disciplinary wound care. Control group (N = 15; 15 analysed*): Standard multiple therapy including surgical debridement, incision and drainage, regular dressing, antibiotics and insulin administration. Experimental group (N = 15; 15 analysed*): As above plus four sessions of oxygen breathing at 3ATA for 45 minutes over a period of 2 weeks.

The Evidence:

Outcome Time to Outcome Control group HBO group Relative risk reduction Absolute risk reduction NNT
Major amputation unknown 0.467 0.133 72% 0.334 3
95% CI: 6% to 100% 0.029 to 0.639 2 to 35

Non-Event Outcomes Time to outcome Control group HBO group P-value Ave hospital stay (days) discharge 47 40.6 NS

Comments: 1. Unblinded trial which may result in bias as the surgeon was aware of treatment group when deciding on need for amputation. 2. There was a trend for shorter hospital stay with hyperbaric oxygen, but difference did not reach statistical significance. 3. Unusual hyperbaric treatment protocol- only four treatments. *Note: actual numbers not present in the paper, we have assumed 15 in each group.

Expiry date: July 2021 References: 1. Doctor N, Pandya S, Supe A. Hyperbaric oxygen therapy in diabetic foot. Journal of Postgraduate Medicine 1992; 38:112-114.