Hypothermic Cardiac Arrest
Accidental hypothermia fundamentally alters physiology and the response to resuscitation. Management prioritises rewarming while maintaining high‑quality cardiopulmonary support, anticipating prolonged efforts and early multi‑specialty involvement.
Follow standard ALS algorithms but apply temperature‑dependent modifications (Resuscitation Council UK). Good neurological recovery is possible even after prolonged arrest if rewarming and perfusion are restored.
Why hypothermic arrest is different
- Metabolism, drug clearance and myocardial contractility are reduced; electrical conduction slows and myocardial irritability increases.
- Vital signs (pulse, respirations) may be extremely slow or faint - allow up to 60 seconds to detect life signs in unconscious hypothermic patients.
- Defibrillation, vasopressors, pacing and some invasive procedures are less effective or may provoke arrhythmia at low core temperatures.
- Definitive therapy is rewarming; extracorporeal support (VA‑ECMO/CPB) provides the fastest, most controlled means of rewarming and circulatory support in arrested patients.
Physiological stages (typical progression)
Use core temperature when available. If unavailable, use the Swiss clinical staging and manage conservatively. Low‑reading core thermometers are essential.
Initial assessment and immediate actions
- Ensure scene safety and follow standard resuscitation priorities; call for senior help early and consider retrieval/ECLS teams if available.
- Measure core temperature with a low‑reading device: tympanic probe for spontaneously breathing patients, oesophageal probe for intubated patients; low‑reading bladder or rectal probes are alternatives (Resuscitation Council UK).