Prevention of surgical site infection in lower limb skin lesion excisions with single dose oral antibiotic prophylaxis: a prospective randomised placebo-controlled double-blind trial.

Objectives: To determine the effectiveness of a single perioperative prophylactic 2 g dose of cephalexin in preventing surgical site infection (SSI) following excision of skin lesions from the lower limb.

Design: Prospective double-blinded placebo-controlled trial testing for difference in infection rates.

Setting: Primary care in regional North Queensland, Australia.

Participants: 52 patients undergoing lower limb skin lesion excision.

Interventions: 2 g dose of cephalexin 30-60 min before excision.

Main Outcome Measures: Incidence of SSI.

Results: Incidence of SSI was 12.5% (95% CI 2.7% to 32.4%) in the cephalexin group compared with 35.7% (95% CI 18.6% to 55.9%) in the placebo group (p=0.064). This represented an absolute reduction of 23.21% (95% CI -0.39% to 46.82%), relative reduction of 65.00% (95% CI -12.70% to 89.13%) and number-needed-to-treat of 4.3.

Conclusions: Administration of a single 2 g dose of cephalexin 30-60 min before skin lesion excision from the lower limb may produce a reduction in the incidence of infection; however, this study was underpowered to statistically determine this.

Trial Registration Number: ACTRN12611000595910.