Pediatric cardiac arrest in the operating room (PALS 2025)
Stem
A 3-year-old boy, 14 kg, is having a sevoflurane mask induction for dental rehabilitation; an IV is not yet placed. During excitement he develops stridor, then silent obstruction. Saturation falls to 62%, and the heart rate drops from 130 to 48 per minute with a weak, then absent, pleth. Jaw thrust and CPAP move no air.
Question
What is happening, and how do you resuscitate him?
Ideal answer
HeadlineLaryngospasm causing hypoxic bradycardia, now with no perfusion: this is an arrest. I call for help and the cart, oxygenate, and start compressions.
- Break the spasm and intubate, because hypoxia is the commonest cause of bradycardia in children; without IV or perfusion, succinylcholine and atropine go intraosseous, not IM.1
- Compressions at a heart rate under 60 with poor perfusion, not waiting for asystole: 100–120 per minute, one-third of chest depth, 15:2 until intubated.2
- Intraosseous access, epinephrine 10 mcg/kg, about 0.14 mg, every 3–5 minutes, maximum 1 mg,2 given as early as possible in a non-shockable rhythm.3
- Pads on: VF gets 2, then 4 J/kg, compressions resuming immediately after each shock.2
- Sevoflurane off; causes reviewed aloud: overdose, hypovolemia, hyperkalemia.
Watch for: end-tidal CO2 above 10 mmHg during compressions; a sudden rise means return of circulation.1
Breaking down the answer
- Why hypoxia first — in children the arrest is usually respiratory or hypovolemic, not cardiac; POCA data since 1998 show cardiovascular and respiratory mechanisms leading, with medication arrests down to 18%.4 Changes if: the rhythm is VF from the start, then shock first.
- Bradycardia thresholds — the SPA card treats under 80 per minute in infants under a year and under 60 at a year or older as bradycardia; hypotension, poor perfusion or pulselessness means compressions and epinephrine.1
- Atropine has a narrow role — for a vagal mechanism or with succinylcholine, 0.02 mg/kg;1 it does not fix hypoxic myocardium, so oxygen and compressions come first.
- Ventilation once intubated — continuous compressions with 20–30 breaths per minute,3 avoiding hyperventilation that cuts venous return.
- Antiarrhythmics — shock-refractory VF gets amiodarone 5 mg/kg, maximum 300 mg, repeatable to 3 doses, or lidocaine 1 mg/kg; later shocks 4 J/kg or more, maximum 10 J/kg or the adult dose.2
- Dose safety — I draw epinephrine as 0.1 mg/mL, 0.1 mL/kg, and say the dose in micrograms and milliliters aloud; tenfold errors are the classic pediatric drug error.
Follow-up question
After 4 minutes he has a pulse and is intubated. The dentist now mentions the boy walks late and falls often. Ten minutes later, while you place an IV, the ECG shows peaked T waves widening into a sine wave, then ventricular fibrillation. What is happening, and what do you do?
Follow-up answer
HeadlineHyperkalemic arrest, likely succinylcholine in an undiagnosed myopathy such as Duchenne. I tell the room, restart CPR and shock.
Compressions and 2 then 4 J/kg; calcium chloride 20 mg/kg or calcium gluconate 60–100 mg/kg, watching the site; dextrose 0.5–1 g/kg with insulin 0.1 unit/kg, maximum 10 units; bicarbonate 1–2 mEq/kg; hyperventilation; no potassium-containing fluid.1 If no return of circulation after 6 minutes, I activate ECMO if available.1 I check potassium and CK, avoid volatile agents from here on, and tell the parents what happened and why.
Pitfalls that cost points
- Treating a bradycardic, hypoxic child with repeated atropine while the airway stays obstructed.
- Routine calcium or bicarbonate in every pediatric arrest; AHA 2025 recommends against both unless a specific indication such as hyperkalemia exists.3
- Stopping compressions to feel for a pulse when capnography and the arterial trace answer the question.
Rapid-fire
Q: Diastolic target with an arterial line? A: At least 25 mmHg in infants and at least 30 mmHg in children a year or older.3
Q: Compression-to-ventilation ratio without an airway? A: 15:2 with two rescuers before puberty; 30:2 with one rescuer or after puberty.2
Q: When is ECPR reasonable? A: AHA says it may be considered for in-hospital arrest refractory to conventional CPR in selected populations;3 SPA advises activating ECMO if no return after the second epinephrine dose.1
Q: After return of circulation? A: SpO2 94–99%, systolic and mean pressure above the 10th percentile, no temperature above 37.5 °C, continuous EEG for seizures.3
Q: Does an end-tidal CO2 value tell you to stop? A: No; AHA rates using a cutoff alone to end resuscitation as harmful.3
Numbers to know
| Item | Value |
|---|---|
| Epinephrine | 0.01 mg/kg (10 mcg/kg) IV/IO every 3–5 min, max 1 mg2 |
| Defibrillation | 2 J/kg, then 4 J/kg; max 10 J/kg or adult dose2 |
| Amiodarone / lidocaine | 5 mg/kg (max 300 mg) / 1 mg/kg2 |
| Compressions | 100–120/min, one-third chest depth2 |
| Breaths with advanced airway | 20–30/min3 |
| Calcium for hyperkalemia | CaCl 20 mg/kg or gluconate 60–100 mg/kg1 |
Links
- laryngospasm, Intraoperative cardiac arrest: care after return of circulation, ACLS adapted to the operating room, hyperkalemia, Muscular dystrophies and myotonias, Neonatal physiology and resuscitation
- 2025 AHA/AAP Pediatric Advanced Life Support guidelines; SPA Pedi Crisis checklists
Sources
- 1.Pedi Crisis critical events checklists (cardiac arrest, bradycardia, hyperkalemia, laryngospasm cards) · Society for Pediatric Anesthesia, 2025 · pedsanesthesia.org
- 2.Pediatric Cardiac Arrest Algorithm · AHA / AAP, 2025 · cpr.heart.org
- 3.Part 8: Pediatric Advanced Life Support (2025 AHA and AAP Guidelines for CPR and ECC) · AHA / AAP, 2025 · cpr.heart.org
- 4.An update on the mechanisms and risk factors for anesthesia-related cardiac arrest in children: a narrative review · Braz J Anesthesiol (PMC11252773), 2024 · pmc.ncbi.nlm.nih.govSummarizes POCA registry mechanisms (1998-2004: cardiovascular 41%, respiratory 27%, medication 18%) and risk factors.
Facts on this page were checked against these sources on Nov 2, 2026. Guidelines change; confirm doses against current institutional protocols.