Effects of preoperative warming on the incidence of wound infection after clean surgery: a randomised controlled trial

Background Wound infection after clean surgery is an expensive and often un derestimated cause of patient morbidity, and the benefits of using prophyla ctic antibiotics have not been proven. Warming patients during colorectal s urgery has been shown to reduce infection rates. We aimed to assess whether warming patients before short duration, clean surgery would have the same effect. Methods 421 patients having clean (breast, varicose vein, or hernia) surger y were randomly assigned to either a non-warmed (standard) group or one of two warmed groups (local and systemic). We applied warming for at least 30 min before surgery. Patients were followed up and masked outcome assessment s made at 2 and 6 weeks. Findings Analysis was done on an intention-to-treat basis. We identified 19 wound infections in 139 non-warmed patients (14%) but only 13 in 277 who r eceived warming (5%; p=0.001). Wound scores were also significantly lower ( p=0.007) in warmed patients. There was no significant difference in the dev elopment of haematomas or seromas after surgery but the non-warmed group we re prescribed significantly more postoperative antibiotics (p=0.002) Interpretation Warming patients before clean surgery seems to aid the preve ntion of postoperative wound infection. If applied according to the manufac turers guidelines these therapies have no known side-effects and might, wit h the support of further studies, provide an alternative to prophylactic an tibiotics in this type of surgery.