Injury severity dictates individualized antibiotic therapy in penetrating abdominal trauma

Antibiotics play a crucial role in reducing the risk of postoperative infection in patients suffering penetrating abdominal trauma. The infection rate for patients with these injuries ranges from 7% to 16%. Single agents with broad-spectrum activity have proven efficacy, but dosage and duration are still controversial. A prospective, double-blinded study was performed on 102 patients randomized to receive one of three antibiotics for a total of 12 hours: cefoxitin (3 doses, 31 patients); ceftizoxime (2 doses, 36 patients); or mezlocillin (3 doses, 35 patients). Two distinct groups at risk for postoperative infection were evident depending on the severity of injury: Group A were those with no colon injury or a colon injury that could be repaired, no evidence of shock, or fewer than 3 organs injured; Group B were those requiring a colostomy, evidence of shock on presentation, or three or more organs injured. All comparisons of the patient populations receiving the different antibiotics showed the two groups to be equivalent. The mean penetrating abdominal trauma index for Group A was 8.8 and 28.2 for Group B. The overall infection rate for Group A was 10.3% and 42.3% for Group B. There was a significant increase in infection rate for all antibiotics except ceftizoxime in Group B compared with group A. The penetrating abdominal trauma index was significantly higher in all patients who developed infection for all antibiotics. In addition, if the surgical wound was closed primarily, patients with colon injuries developed wound infections 71% of the time, and those with small-bowel injuries did so 30% of the time.(ABSTRACT TRUNCATED AT 250 WORDS)