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Perioperative cardiac arrest and resuscitation
Cardiac arrest in theatre is usually witnessed and monitored in real time — so the cause specific to it (airway, bleeding, drugs, high block, anaphylaxis) is sought at once while high-quality ALS resuscitation goes on.
Why it matters in the exam
The exam asks about the resuscitation algorithm (shockable versus non-shockable rhythm, when adrenaline and amiodarone are given and at what dose), the quality of compressions and the meaning of EtCO2 during resuscitation. Anaesthesia-specific questions deal with vagal bradycardia from peritoneal traction or pressure on the eye, arrest after a high spinal block, LAST, anaphylaxis, hyperkalaemia after succinylcholine or massive transfusion, and tension pneumothorax.
Compressions at 100–120 per minute and 5–6 cm deep, with minimal pauses; after intubation compressions are continuous and ventilation is 10 breaths per minute. In a shockable rhythm a shock is given, and once three shocks have been given, adrenaline 1 mg plus amiodarone 300 mg; adrenaline is repeated every 3–5 minutes. In a non-shockable rhythm adrenaline 1 mg is given as early as possible. An EtCO2 below 10 mmHg suggests ineffective compressions or a very low output, and a sudden jump suggests return of circulation.
Theatre has an advantage: the patient is monitored, ventilated and sometimes has an arterial line, so the moment and the cause can be identified. During resuscitation volatile agents and anaesthetic drugs are stopped, 100% oxygen is given, the team and the surgeon are told, and the tube, the ventilation and the bleeding are checked at once. In a prone patient compressions can start on the back until the patient is turned. After return of circulation saturation is kept at 94%–98%, MAP at 65 or more, and fever is prevented.
Key points
- Compressions 100–120 per minute, 5–6 cm deep, minimal pauses.
- VF/VT: shock; after the third, adrenaline 1 mg and amiodarone 300 mg.
- Asystole/PEA: adrenaline 1 mg early.
- In theatre: look for a specific cause — airway, bleeding, high block, LAST, anaphylaxis, hyperkalaemia.
- After ROSC: saturation 94%–98%, MAP of 65 or more, fever prevention.
Summary table
| Anaesthesia-specific cause | Clue | Focused treatment |
|---|---|---|
| Vagal bradycardia | Peritoneal traction, pressure on the eye, laryngoscopy | Stop the stimulus, atropine 0.5–1 mg, and adrenaline if needed |
| High spinal block | Hypotension and bradycardia after a spinal | Early adrenaline, ventilation, fluids |
| LAST | After a block or a large dose of local anaesthetic | 20% lipid emulsion, small doses of adrenaline |
| Hyperkalaemia | After succinylcholine or massive transfusion, peaked T waves | Calcium, insulin with glucose, bicarbonate |
| Tension pneumothorax / auto-PEEP | High ventilation pressures, reduced sounds on one side / a COPD patient | Needle decompression / disconnect from the ventilator |
In the full version for subscribers
- A simple algorithm
- Memory aid
- Exam traps
- 5 review cards
- Enough for IMLE
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Sources
- European Resuscitation Council Guidelines, 2021 — Adult advanced life support; Cardiac arrest in special circumstances (perioperative)
- AHA Guidelines for CPR and Emergency Cardiovascular Care, 2020 — Adult advanced life support
- Miller's Anesthesia, 9th edition (2020) — Cardiopulmonary Resuscitation and Advanced Cardiac Life Support
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-02. The text may contain errors; when in doubt, check the source.