Early-onset neonatal sepsis — structured SAQ (15 marks)

(a) Immediate priorities — first hour (5 marks)

One mark per point, maximum five. ^[1][2]

• Recognise this is suspected early-onset neonatal sepsis. The infant has the full risk tier — GBS-positive mother, ROM 26 hours, intrapartum fever, inadequate IAP (only 2 of the recommended minimum 4 hours) — and is now showing systemic signs (grunting, tachypnoea, tachycardia, prolonged capillary refill, hypothermia).^[2][4]
• Call for help and escalate to neonatal team — paediatric or neonatal registrar immediately; this infant needs neonatal unit admission, not postnatal ward observation.
• Airway, breathing and circulation — supplemental oxygen for the grunting, secure IV or intraosseous access, assess for shock and give a 10 mL/kg isotonic crystalloid bolus if perfusion does not improve.^[2]
• Blood culture before antibiotics whenever possible, plus FBC with differential and CRP at baseline.^[1]
• Empirical antibiotics within one hour of the decision to treat — benzylpenicillin 60 mg/kg IV plus gentamicin 5 mg/kg IV in ANZ practice — and state the 48-hour checkpoint out loud.^[1][3]

Reasoning mark awarded for naming the GBS-fever-ROM-prematurity tier and the inadequate-IAP interaction. ^[2][5]

(b) Investigations and sequence (3 marks)

Order matters — culture first. ^[1][3]

1. Blood culture taken before any antibiotic is given — the single most important test, and one that is blinded by antibiotics given first.
2. Full blood count with differential and C-reactive protein at baseline.
3. Lumbar puncture if the infant is stable enough for the procedure — CSF cell count, protein, glucose, culture. Meningitis cannot be reliably excluded without it.^[1]
4. Bedside glucose with the septic screen — hypoglycaemia is both a mimic and a complication.

(c) Empirical antibiotic regimen (3 marks)

One mark for the agents, one for the doses, one for the rationale. ^[1]

• Benzylpenicillin 60 mg/kg IV at the gestational-age and postnatal-age appropriate interval — reliable activity against GBS, the dominant term-infant pathogen.
• Gentamicin 5 mg/kg IV at extended interval — gram-negative cover and synergy with the beta-lactam.
• Rationale — the beta-lactam-plus-aminoglycoside combination covers the two leading pathogens (GBS and E. coli) with a narrow spectrum, narrows to a single agent once an organism is identified, and respects the stewardship principle that empirical therapy must be effective and limited.^[1][2]
• Regional note (one mark if volunteered): NICE NG195 uses benzylpenicillin 25 mg/kg 12-hourly plus gentamicin 5 mg/kg every 36 hours; the AAP uses ampicillin plus gentamicin. The agent differs; the principle is identical.^[1]

(d) Culture-negative at 48 hours (2 marks)

• Stop the empirical antibiotics at 48 hours. The criteria for stopping — cultures negative, CRP low, infant clinically well and feeding — are all met.^[1][3]
• Discharge with a parental safety-net conversation documented in the notes — return if poor feeding, lethargy, fever, or abnormal breathing. The 48-hour stop is the stewardship rule that protects the infant from the harm of prolonged broad-spectrum exposure.^[1]

(e) Communication (2 marks)

Scored against the rapport and communication domains of the RANZCOG oral exam. ^[1]

• Plain language, no jargon: "Your baby became unwell in the first few hours, and we treated him with antibiotics because we were worried about an infection he may have picked up around the time of birth. The tests so far have not grown any bacteria. We are stopping the antibiotics now because he is well, and we will keep a close eye on him on the ward before he goes home."^[1]
• Acknowledge maternal fear and guilt directly — the GBS colonisation is not the mother's fault, and the colonisation-and-prophylaxis model exists precisely because this is a common and unpredictable problem.
• Commit to a clear plan and to a debrief.