Infectious disease relations to cesarean section.

Patients delivered by cesarean section are at risk for postoperative infectious morbidity, especially those patients who have labored with ruptured membranes for a long period of time. The bacteria involved in these infections are predominantly those of the patient's lower genital tract, both aerobes and anaerobes. Antibiotic prophylaxis has reduced the risk of postpartum infection but has also resulted in selection of resistant bacteria. Treatment of postpartum endometritis has classically been with clindamycin plus an aminoglycoside. However, the newer beta-lactam antibiotics have proved to be just as efficacious. A significant advance in the treatment of postpartum endometritis is the use of beta-lactamase inhibitors combined with beta-lactams, such as clavulanic acid plus ticarcillin or ampicillin plus sulbactam. Regardless of which antibiotic is chosen for treatment, it is important to know the weakness of each antibiotic. For example, cephalosporins such as cefoxitin or cefotetan do not have activity against Strep. faecalis, Ent. cloacae, or Pseudomonas aerugenosa; mezlocillin, ticarcillin, or piperacillin tend to be weakest against the gram-negative facultative anaerobes; and combinations such as clindamycin plus gentamicin do not provide coverage against Strep. faecalis. This knowledge of the weakness of the different antibiotics permits appropriate additions to the antibiotic regimen and avoids irrational changes in antibiotic therapy.