Comparison of Cefazolin and Cefazolin+Gentamicin on Surgical Site Infection of CABG Patients

Background and

Surgical Site Infection (SSI) is the third leading cause of hospital infections and lead to increased morbidity, mortality and costs after cardiac surgery. The importance of prophylactic antibiotics in cardiac surgery has been proved. The aim of this randomized clinical trial was to compare of two prophylactic antibiotic regimens (cefazolin and cefazolin + Gentamicin) on surgical site infection of CABG patients in Mazandaran Heart Center.

A total of 400 patients, meeting eligibility criteria, were randomly allocated into two equal groups. In the control group the prophylactic regimen consists of Cefazolin 2 g IV before sternal incision followed by 1 g IV every 6 hours for 72 hours. In the intervention group the prophylactic regimen consists of Cefazolin 2 g IV plus Gentamicin 1.5mg/kg IV before sternal incision followed by Cefazolin 1 g IV every 6 hours plus Gentamicin 1.5mg/kg IV every 8 hours for 72 hours. Patients were observed by cardiac surgeon for signs of surgical wound infection at 3, 7, 21 and 30 days after cardiac surgery. Also Creatinine and BUN was measured before, 2th and 4th days after surgery. Data were analyzed by Independent t test, Paired t test, Chi-Square, Fisher and Repeated Measures tests.

392 of 400 patients were examined, 198 patients in control group and 194 patients in intervention group. There was no significant difference between the two groups regarding demographic and clinical variables (P>0.05). After intervention there was no significant difference between the two groups regarding the incidence of infection (P>0.05) but serum level of Creatinine and BUN was significantly higher in intervention group (P<0.05).

With considering to the lack of significant difference in infection rates between two groups and significant increase in serum level of Creatinine and BUN in intervention group, Cefazolin alone is sufficient as a prophylactic antibiotic to prevent surgical site infection of CABG patients.