Timing of Preoperative Antibiotics in PPROM Before Cesarean Section
Administer intravenous antibiotics 30-60 minutes before skin incision (Answer B: 60 minutes before incision). This timing ensures therapeutic antibiotic concentrations are achieved in maternal tissues before bacterial contamination occurs during surgery, reducing the risk of postoperative infections in women with PPROM. 1
Recommended Timing Window
The ERAS Society guidelines recommend that intravenous antibiotics should be administered routinely within 60 minutes before the cesarean delivery skin incision, with high-quality evidence and a strong recommendation grade. 1
ACOG supports the administration of antibiotics 30-60 minutes prior to the start of surgery, as this timing ensures therapeutic antibiotic concentrations are achieved in maternal tissues before bacterial contamination occurs during surgery. 1
The FDA labeling for cefazolin (the first-line agent) specifies administration 1/2 hour to 1 hour (30-60 minutes) prior to the start of surgery for perioperative prophylaxis. 2
Rationale for This Specific Timing
PPROM represents a higher-risk scenario, classified as a clean-contaminated (class II) or potentially contaminated (class III) incision, carrying increased risk from both skin flora and vaginal flora exposure. 1
Historical practice has shifted from administering antibiotics after cord clamping to pre-incision administration, as current evidence demonstrates that pre-incision administration decreases wound infections without causing fetal harm in patients undergoing cesarean section, including those with PPROM. 1
The 30-60 minute window allows adequate time for the antibiotic to reach therapeutic levels in serum and tissues at the time of initial surgical incision. 1, 2
Recommended Antibiotic Regimen
First-generation cephalosporin (cefazolin) is the primary choice for all women undergoing cesarean section, including those with PPROM. 1
The addition of azithromycin is recommended in women in labor or with ruptured membranes, as this confers additional reduction in postoperative infections beyond cephalosporin alone. 1
For penicillin allergy, clindamycin or erythromycin can be used. 3
Critical Pitfall to Avoid
Do not delay antibiotic administration until after cord clamping in the setting of PPROM, as this outdated practice increases maternal infection risk without providing fetal benefit. 1
Administering antibiotics too early (>60 minutes before incision) may result in subtherapeutic levels at the time of incision, while administering too late (after incision) fails to provide adequate tissue levels when bacterial contamination occurs. 1, 2