A retrospective review of three antibiotic prophylaxis regimens for pediatric cardiac surgical patients

Background Optimal antimicrobial prophylaxis for the pediatric cardiac surgical patient is unknown. We have reviewed our experience with more than 4,000 pediatric cardiac surgical patients at the University of Michigan to evaluate antibiotic prophylaxis regimens. Methods Three antibiotic prophylaxis protocols were serially used during a 6-year period: Protocol 1 (n = 786): cefazolin was administered before operation and continued as long as thoracostomy tubes or central venous catheters were present; Protocol 2 (n = 1095): cefazolin was discontinued 48 hours postoperatively, regardless of the presence of tubes or catheters; Protocol 3 (n = 2039): cefazolin was continued as long as thoracostomy tubes were present, but not for central venous catheters. Patients with an open chest postoperatively received vancomycin and gentamicin until chest closure. This was identical during all three protocols. We retrospectively determined the rate of surgical site infections and unrelated bloodstream infections (the latter for both cardiac medical and surgical patients) for the three protocols. Results Surgical site infections per 100 operations for protocols 1, 2, and 3 was 2.04, 6.58, and 1.67, respectively (p< 0.05 for protocol 2 versus protocols 1 and 3). The mean age of patients with a surgical site infection ranged from 12 to 15.4 months. Patients with an open chest had a higher rate of surgical site infection (18.8% for protocol 2 and 9.3% for protocol 3). Bloodstream infections per 1,000 patient days for protocols 1, 2, and 3 were 2.18, 6.51, and 5.02, respectively (p<0.05 protocol 1 versus protocols 2 and 3). Conclusions These data suggest that pediatric cardiac surgical patients may benefit from prophylactic antibiotics as long as thoracostomy tubes are in place.