Resuscitate a cyanotic neonate with prostaglandin E1 — OSCE

Candidate brief

You have eight minutes to manage a ward call about a cyanotic two-day-old with a suspected duct-dependent congenital heart lesion. Use a structured approach: recognise the emergency and do not wait for echocardiography, start prostaglandin E1 at the weight-based dose, anticipate and prepare for the adverse effects, set the target saturation, and explain the plan to the nurse and to the family in plain language. [10]

Key teaching and decision objectives

Recognise the emergency and act before the scan. A cyanotic, acidotic neonate in the first days of life whose saturation does not rise with oxygen must be assumed to have a duct-dependent lesion until proven otherwise. The ductus arteriosus is closing, and the circulation depends on it. Echocardiography confirms the anatomy but must not delay the resuscitative drug. Start prostaglandin E1 (alprostadil) at once. [10]

State the dose and titration. Start prostaglandin E1 at 0.01 to 0.05 microgram per kilogram per minute intravenously and titrate upward toward a typical maximum around 0.1 microgram per kilogram per minute, watching for the response: a rising saturation, a warming perfusion, and a falling lactate. Confirm the current weight before prescribing, because the dose is weight-based and a decimal-point error in an infusion is dangerous. [10]

Set the target saturation and explain why. The target is around 75 to 85 per cent, not a normal saturation, because excessive pulmonary flow across the duct steals blood from the systemic circulation and can worsen the acidosis. Titrate to the perfusion and the lactate as well as to the number. [10]

Anticipate and prepare for the adverse effects. Three adverse effects are expected. Apnoea is common — have a plan for intubation and ventilation. Fever can mislead the team toward a septic work-up; recognise it as a drug effect while still taking cultures and considering antibiotics. Hypotension is managed with volume and, where needed, a low-dose vasopressor. [10]

Communication to the nurse and family

To the nurse (plain language): "This baby almost certainly has a heart problem that depends on a blood vessel called the ductus, which is closing. We need to start a medicine called prostaglandin through the drip right now to keep that vessel open — I do not want to wait for the heart scan. Please set up the infusion at the dose I have written, and prepare for the possibility that the baby may need help with breathing, because this medicine commonly causes pauses in breathing. Watch the oxygen, the breathing rate, the temperature and the blood pressure, and call me back at the first change." [10]

To the family (plain language): "Your baby's heart problem means that a blood vessel he needed at birth is closing, and that is why he has gone blue. There is a medicine we can give through the drip that keeps that vessel open and gets the blood flowing again. I'm starting it now because waiting is not safe. The medicine can make some babies pause their breathing, run a fever, or drop their blood pressure, so we will watch him very closely and help his breathing if needed. We are also arranging to move him to a children's heart centre where the team can see exactly what the heart needs next." [10]

Marking domains

• Clinical reasoning (30 per cent): recognises a duct-dependent emergency; starts prostaglandin E1 without waiting for echocardiography; sets a 75 to 85 per cent target and explains why.
• Decision-making (25 per cent): states the weight-based dose and titration; prepares for apnoea, fever and hypotension; confirms the current weight.
• Communication to the nurse (20 per cent): gives clear infusion instructions; asks for close monitoring of saturation, breathing, temperature and blood pressure; prepares for intubation.
• Communication to the family (15 per cent): explains the emergency and the drug in plain language; names the adverse effects honestly; reassures while being truthful.
• Safety and follow-up (10 per cent): organises retrieval to a cardiac centre; documents the dose and titration; takes cultures and considers antibiotics alongside without delaying the prostaglandin. [7] [10]