ABSTRACT
The authors present a prospective randomized double-blind clinical trial, including 179 patients submitted to elective gastrointestinal surgery, for the purpose of evaluating three philosophic conceps of antibiotic prophylaxis (PA): systematic antibiotic prophylaxis for 48 h with sodium cefuroxim, 1.5 g the first dose and subsequent doses of 750 mg iv; selective antibiotic prophylaxis based on determination of preoperative gastric pH (pH less than 4, no antibiotic prophylaxis, and pH greater than 4, prophylaxis as in group I); and antibiotic therapy beginning postoperatively with cefuroxim 750 mg every 78 h for 4 days. The postoperative infection rate was 2% in the systematic prophylaxis group, 4% in the selective prophylaxis group, 24% in the antibiotic therapy group and 17.2% in the control group (p less than 0.001). The postoperative infection rate between the systematic and elective prophylaxis groups was statistically similar (p = NS). In conclusion, selective antibiotic prophylaxis has an incidence of postoperative infection similar to that of systematic prophylaxis, and, oriented by gastric pH determination, can be indicated only in patients with bacterogastria. Finally, we confirm that antibiotic therapy of postoperative onset should be eliminated as a method of prevention of postoperative infection.
