How to prevent postpartum pelvic infection in a patient at a certain gestational age with premature rupture of membranes (PROM) for a specified time frame who is planned for cesarean section (C-Section)?

Prevention of Postpartum Pelvic Infection in PROM with Planned Cesarean Section

For a patient with PROM planned for cesarean section, administer cefazolin 1-2 grams IV 30-60 minutes before skin incision, with the addition of azithromycin 500 mg IV for enhanced coverage given the membrane rupture. 1

Critical Timing Considerations

• Antibiotic administration must not be delayed once PROM is diagnosed, as maternal infection can progress with devastating speed—the median time from first signs of infection to death is only 18 hours in severe cases. 1
• The preoperative antibiotic dose must be given 30-60 minutes prior to surgical incision to ensure adequate serum and tissue levels at the time of initial incision. 2
• Waiting for signs of infection before starting antibiotics is dangerous, as clinical deterioration occurs rapidly once infection develops. 1

Antibiotic Regimen for Cesarean Section with PROM

Primary Surgical Prophylaxis

• Cefazolin 1-2 grams IV is the standard perioperative prophylactic agent for cesarean delivery. 2
• For patients with ruptured membranes undergoing cesarean section, add azithromycin 500 mg IV to the cefazolin regimen for comprehensive coverage. 1
• This combination provides coverage against aerobic gram-negative organisms and anaerobic bacteria, which are the primary pathogens in postpartum endometritis and pelvic infections. 1

Alternative Regimen (If Penicillin Allergy)

• If anaphylactic penicillin allergy exists, use clindamycin 600 mg IV plus gentamicin 5 mg/kg IV as an alternative combination. 3
• This clindamycin-gentamicin regimen provides comprehensive coverage against both aerobic gram-negative organisms and anaerobic bacteria. 1

Duration of Membrane Rupture Considerations

• The risk of postpartum infection increases continuously with increasing duration of membrane rupture, with risk doubling when membranes have been ruptured for >4 hours. 4
• Prophylactic antibiotics given after cord clamping reduce the rate of postpartum infection among women undergoing cesarean section after labor or rupture of membranes. 4
• At term with prolonged rupture, if the patient's Group B Streptococcal (GBS) status is unknown or positive, add penicillin G or ampicillin for GBS prophylaxis, which can be administered concurrently with the surgical prophylaxis regimen. 1

Postoperative Antibiotic Duration

• Prophylactic antibiotic administration should usually be discontinued within 24 hours after the surgical procedure. 2
• In surgery where infection may be particularly devastating (such as in cases with prolonged membrane rupture), prophylactic administration may be continued for 3-5 days following completion of surgery. 2
• Continue antibiotics until 48 hours of fever resolution and disappearance of pelvic pain if postpartum endometritis develops. 3

Additional Infection Prevention Measures

• Perform vaginal preparation with povidone-iodine or chlorhexidine before cesarean section if possible to reduce bacterial load. 3
• Ensure spontaneous placental extraction rather than manual removal to minimize infection risk. 3
• Avoid invasive monitoring procedures (such as scalp electrodes) if labor precedes cesarean delivery, as these increase infection risk. 4

Monitoring for Postpartum Infection

• Monitor for signs of postpartum endometritis: abdomino-pelvic pain, fever >38°C, abnormal or foul-smelling lochia, and uterine tenderness on examination. 3
• If fever or pelvic pain persists after 72 hours of antibiotic therapy, obtain pelvic imaging to evaluate for retained placental tissue, septic thrombophlebitis, deep abscess, or other surgical complications. 3
• Be aware that postpartum hemorrhage occurs in 23.1% of cases with membrane rupture and requires vigilant monitoring. 5

Common Pitfalls to Avoid

• Do not delay antibiotic administration waiting for signs of infection—prophylaxis must be given before skin incision. 1, 2
• Do not rely solely on maternal fever to diagnose chorioamnionitis, as other signs (maternal tachycardia, uterine tenderness, fetal tachycardia) may appear first. 5
• Do not perform digital cervical examinations in patients with PROM who are not in active labor, as this increases infection risk. 6