Maternal Sepsis

Maternal sepsis is life threatening organ dysfunction caused by dysregulated host response to infection occurring during pregnancy, childbirth, post-abortion or postpartum (up to 42 days). It is a leading cause of direct maternal death worldwide (about 10% of maternal deaths; incidence of about 5 to 10 per 1,000 deliveries in low income countries and 0.1 to 0.6 per 1,000 in high income countries).

The most common sources are genital tract infection (chorioamnionitis, endometritis, wound infection, septic abortion), urinary tract (pyelonephritis), respiratory (pneumonia, influenza), breast (mastitis, abscess), and soft tissue (necrotising fasciitis).

Organisms: group A streptococcus (the leading cause of death), E. coli, Staphylococcus aureus (including MRSA), group B streptococcus, Klebsiella, anaerobes, Clostridium, and viruses (influenza, SARS-CoV-2). Pregnancy blunts immune response, so deterioration may be rapid.

• Fever or hypothermia, rigors, tachycardia (above 100/min), tachypnoea (above 20/min), hypotension, altered mental status, oliguria, and abdominal or perineal pain
• Foul lochia, uterine tenderness, wound erythema, breast pain, sore throat in contacts (GAS)
• Severe pain out of proportion to signs suggests necrotising fasciitis
• Vital sign abnormalities can be subtle initially; obstetric early warning scores identify at risk women (maternal sepsis screen: temperature above 38 or below 36, heart rate above 100, respiratory rate above 20, systolic BP below 100, altered consciousness, oliguria)
• Signs of organ dysfunction: confusion, jaundice, bleeding, dyspnoea, low urine output, cold peripheries

• Sepsis suspected by clinical criteria and maternal modified qSOFA (omqSOFA: systolic BP 90 or below, respiratory rate 25 or above, altered mentation)
• Lactate (above 2 mmol/L), full blood count, C-reactive protein, procalcitonin, urea, creatinine, liver function tests, coagulation profile, blood gas, urinalysis
• Cultures before antibiotics (blood, urine, high vaginal swab, wound swab, placental tissue, throat swab, sputum), and swabs for GAS and viral PCR
• Imaging: pelvic ultrasound for retained products and collections, CT or MRI for abscess, necrotising fasciitis, septic pelvic thrombophlebitis, chest imaging; echocardiography when endocarditis or cardiomyopathy
• Placenta culture and histology

• Sepsis Six within 1 hour:
  1. Oxygen to keep saturations 94 to 98%
  2. Blood cultures (and lactate) before antibiotics
  3. Broad spectrum IV antibiotics within 1 hour (see the list of regimens that follows)
  4. IV crystalloid 30 mL/kg (or 500 mL boluses reassessed, with caution for pre-eclampsia) for hypotension or lactate above 4 mmol/L
  5. Monitor lactate and urine output (catheter, target 0.5 mL/kg/hour)
  6. Early senior review, with source control

Antibiotic regimens:

• Piperacillin tazobactam 4.5 g IV every 6 to 8 hours, or ceftriaxone 2 g with metronidazole 500 mg.
• Add clindamycin 900 mg IV every 8 hours (toxin suppression) for suspected GAS, necrotising infection or toxic shock.
• Add gentamicin 5 mg/kg once daily if resistant organisms are suspected.
• Meropenem 1 g every 8 hours if septic shock or ESBL risk.
• Add vancomycin 15 to 20 mg/kg every 8 to 12 hours for suspected MRSA.
• Consider oseltamivir 75 mg twice daily for influenza.

Further management:

• Vasopressors (noradrenaline first line, target MAP at least 65 mmHg) after fluid resuscitation.
• Hydrocortisone 200 mg/day for refractory shock.
• Source control: evacuation of retained products, drainage of abscess, debridement, hysterectomy for uterine necrosis or refractory sepsis, laparotomy.
• Antepartum: stabilise the mother first, monitor the fetus, and make delivery decisions according to maternal condition.
• Intravenous immunoglobulin (2 g/kg) may be considered in streptococcal toxic shock syndrome.
• VTE prophylaxis (enoxaparin 40 mg daily).
• Critical care for organ failure.
• Infection control and chemoprophylaxis for close contacts in GAS cases.
• De-escalate antibiotics at 48 to 72 hours with cultures. Course typically 7 to 10 days (longer with abscess or bacteraemia).