The acutely unwell patient — ABCDE

Why this matters on day one

You will be the first doctor to see a deteriorating patient, usually alone and usually before you have a diagnosis. ABCDE works precisely because it does not require one: it fixes what is killing the patient in the order that kills them fastest, and it buys the time in which the diagnosis becomes obvious.

The sequence

1. 1Before the bedside. Ask the nurse for the observations, the news, and what has changed. Take the notes and the drug chart. If the words "I'm worried about" are used, believe them — nursing concern outperforms most single observations.
2. 2A — Airway. Talk to the patient: a normal voice is a patent airway. Look for stridor, gurgling, snoring, see-saw breathing. Head tilt/chin lift, suction, airway adjunct. A threatened airway is an immediate call for anaesthetics — do not proceed down the alphabet first.
3. 3B — Breathing. Rate, saturations, work of breathing, tracheal position, percussion, auscultation. High-flow oxygen 15 L/min via a non-rebreathe mask in the acutely unwell (the 88–92% target applies once you know they retain CO₂, not before you know anything). ABG. Chest X-ray.
4. 4C — Circulation. Pulse, blood pressure, capillary refill, JVP, urine output. Two wide-bore cannulae, bloods including cultures, lactate and a crossmatch if bleeding. Fluid challenge 500 mL crystalloid over <15 min (250 mL if frail or in heart failure), then reassess. ECG.
5. 5D — Disability. GCS or AVPU, pupils, capillary GLUCOSE (the single most-missed reversible cause), temperature. Consider naloxone if opioid-related, and look at the drug chart before blaming the disease.
6. 6E — Exposure. Expose fully and look — rashes, wounds, drains, calves, abdomen, back, cannula sites. Rectal examination and pressure areas if indicated. Then reassess from A.
7. 7Then. Document what you found, what you did, what you are waiting for, and who you have called. Set a review time and a specific escalation trigger.

What goes wrong

• Moving past A because the patient "looks alright" — a threatened airway kills in minutes.
• Withholding oxygen from a hypoxic patient for fear of CO₂ retention. Treat the hypoxia; titrate afterwards.
• Forgetting the capillary glucose. It takes ten seconds and it changes management.
• Assessing without treating. ABCDE is treat-as-you-find, not a survey to complete before acting.
• Not going back to A after each intervention.