Evaluation of antibiotic prophylaxis and factors affecting the incidence of surgical site infections in cardiac surgery at a tertiary medical center in Lebanon. (c2004)

Abstract

Background: Appropriate antibiotic prophylaxis can reduce the incidence of surgical site infections (SSI) in many procedures. Although its role is still controversial in a clean surgery such as cardiac, antibiotic prophylaxis has been suggested by many guidelines to avoid the significant morbidity and mortality precipitated by surgical site infections (superficial or deep, leg or sternal). Objectives: The main objective of this study is to evaluate the adherence to rational antibiotic prophylaxis for Open heart surgery at AUB-MC with major criteria being: antibiotic regimen, dose, timing, and duration. In addition, the secondary objectives are to detect the surgical site infection incidence and to identify potential risk factors for infection. Based on the results, recommendation regarding the antibiotic prophylaxis will be made. Materials and Methods: All medical charts of patients undergoing Open heart surgery between October 2002 and April 2003 at AUB-MC and satisfying the inclusion criteria set for selection were reviewed retrospectively. The outcome measures were all diagnosed surgical site infections whether superficial or deep, leg or sternal. Results: One hundred fifty seven patients were included in the retrospective analysis. All patients (100%) received antibiotic prophylaxis regardless of the timing while only 38% received it 30-60 minutes prior to incision. Only 12% of those fitting the criteria for an intraoperative dose did actually receive it. Concerning the duration of prophylaxis, around 15% of patients received up to 5 doses of prophylactic antibiotics post-operatively. The mean number of doses received was 6 ±0.97 regardless of the antibiotic given. Concerning preoperative agents given, cefuroxime alone was used in 74.5% of the cases, while vancomycin alone was common in 5% of cases. The combination of both agents was common in 7.64% of cases. The rest (11.46%) received no preoperative dose at all. Postoperatively, the shares of cefuroxime, vancomycin, and their combination among the population were 91.7%, 3.8%, 2.54% respectively. One patient received cefazolin pre- and post-operatively. Only 2 patients (1.27%) had surgical site infections; they were sternal infections occurring in non smoker elderly male patients undergoing CABO and having no known risk factors for infections at all. Both received cefuroxime pre and postoperatively for 6 doses but no intraoperative antibiotics although their operations lasted for more than 2 hours each (135 min vs 210 min). The added hospital stay was 3 days for one patient and 4 days for the other. One patient had a wound cultured and revealed Pseudomonal growth. Both patients were discharged on antibiotics. Conclusion: Antibiotic prophylaxis in cardiac surgery is a common routine practiced by doctors at AUB-MC. However, there was a trend towards extended prophylaxis and excessive use of cefuroxime. The low number of patients acquiring a surgical site infection (2 patients) at AUB-MC can't allow significant findings and thus hinders further recommendation concerning the practice.