Randomized trial of one-dose versus six-dose cefazolin prophylaxis in elective general thoracic surgery

The objective of this study was to compare the efficacy of one to six doses of cefazolin as prophylaxis in general thoracic surgery using a randomized, double-blind design. Two-hundred eight consecutive patients admitted to a regional thoracic surgery unit for elective thoracotomy and lung resection were eligible for the trial. There were no wound infections in the one-dose group and two in the six-dose group (95% confidence intervals [CI]: -0.008, +0.048 [The positive number refers to the largest possible difference in favor of the one-dose group and the negative number, the largest possible difference in favor of the six-dose group]). Each group had eight postoperative chest infections (CI: -0.075, +0.077) and three empyemas (CI: -0.004, +0.050). Thirty-day mortality was 5% in the one-dose group and 4% in the six-dose group (CI: -0.053, +0.069). Postoperative duration of hospital stay, requirement for antibiotics, and the need for reoperation were comparable. These results suggest that six doses of cefazolin do not confer clinically important benefit beyond that obtained from a single dose for prophylaxis of wound infection in elective general thoracic surgery.