Single-dose prophylaxis with broad-spectrum penicillins (piperacillin and mezlocillin) in gynecologic oncological surgery, with observation on serum and tissue concentrations.

Serum, fat and pelvic tissue levels of piperacillin or mezlocillin (patients randomly selected to receive one of both) were measured during surgery of 48 patients (mean age 55 years) with gynecologic cancer and related to the minimal inhibitory concentrations (MIC). Only during the first 3 hours the fat and pelvic tissue levels of these antibiotics were above the MIC levels (3 to 5 mg/l), while the serum reached marginal levels after 4 to 5 hours. Excessive blood loss (more than 1.500 ml) decreases the serum and fat levels; however, during the first 3 hours not below the MIC values. Single-dose prophylaxis with both antibiotics appeared fully effective in debulking surgery, total abdominal hysterectomy and radical hysterectomy. However, out of a group of 12 patients who underwent radical vulvectomy, 8 patients had postoperative infections.