2025 Korean Guidelines for Cardiopulmonary Resuscitation: Part 5. Cardiac arrest in special circumstances.

The 2025 update of the Korean guidelines for cardiac arrest under special circumstances incorporates new evidence and expert consensus to clarify when clinicians should modify standard resuscitation algorithms. For cardiac arrest caused by acute hyperkalemia, the guidelines suggest administering intravenous insulin with glucose; however, current evidence remains insufficient to recommend for or against routine use of sodium bicarbonate or calcium. In suspected pulmonary embolism-related cardiac arrest, thrombolytic therapy may be considered. In confirmed cases, thrombolysis, surgical embolectomy, or percutaneous mechanical thrombectomy may be appropriate, despite very low certainty of evidence. For opioid-related cardiac arrest, current evidence does not support the routine administration of naloxone in addition to standard advanced life support; however, naloxone may be administered when it is unclear whether the patient is in true cardiac arrest. The guidelines also emphasize managing cardiac arrest in the prone position. If the patient is intubated and immediate repositioning is unsafe or impractical, prone cardiopulmonary resuscitation and defibrillation may be attempted using invasive arterial pressure or end-tidal carbon dioxide monitoring to guide the timing of repositioning. Immediate supination is strongly recommended for non-intubated patients. Additional updates address drowning, severe hypothermia, pregnancy, anaphylaxis, and cardiac arrest during interventional procedures, underscoring the importance of early correction of reversible causes, appropriate airway strategies, and timely consideration of extracorporeal life support in selected cases. Overall, the 2025 recommendations highlight cautious, etiology-directed interventions and explicitly grade recommendation strength and certainty to support context-sensitive clinical decision-making in high-risk and resource-variable settings.