In a prospective study, 150 consecutive obese patients (body mass index?¡Ý?30) with cardiac surgery performed via median sternotomy were analyzed. In the negative pressure wound dressing treatment group (n?=?75), a foam dressing (Prevena, KCI, Wiesbaden, Germany) was placed immediately after skin suturing, and negative pressure of ?125 mm Hg was applied for 6 to 7 days. In the control group (n?=?75), conventional wound dressings were used. The primary end point was wound infection within 90 days. Mann-Whitney U test and Fisher exact test were used. Freedom from infection was estimated by Kaplan-Meier analysis.
Three of 75 patients (4 % ) with continuous negative pressure wound dressing treatment had wound infections compared with 12 of 75 patients (16 % ) with conventional sterile wound dressing (P?=?.0266; odds ratio, 4.57; 95 % confidence interval, 1.23-16.94). Wound infections with Gram-positive skin flora were found in only 1 patient in the negative pressure wound dressing treatment group compared with 10 patients in the control group (P?=?.0090; odds ratio, 11.39; 95 % confidence interval, 1.42-91.36).
Negative pressure wound dressing treatment over clean, closed incisions for the first 6 to 7 postoperative days significantly reduces the incidence of wound infection after median sternotomy in a high-risk group of obese patients.