Analysis on Route with Early Trasnport Considerations?

In medical cardiac arrest cases where a potentially reversible cause cannot be corrected in the field, such as hypothermia, mixed overdose, pregnancy, or a remaining foreign body airway obstruction, should Paramedics continue rhythm analysis every two minutes once transport is prioritized and initiated, or should only one analysis be performed prior to departure similar to a traumatic cardiac arrest?

When a reversible cause cannot be addressed prehospitally, the intent of both AHA and ILCOR guidance is to prioritise high-quality chest compressions, early transport, and minimal interruptions rather than frequent rhythm analyses. The 2020 AHA Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care state that rhythm and pulse checks should be as brief as possible and performed approximately every two minutes only while ongoing resuscitative interventions are likely to influence patient outcome (American Heart Association, 2020). The International Liaison Committee on Resuscitation (ILCOR) similarly notes that frequent rhythm checks during patient movement or transport can degrade CPR quality and are not supported by evidence of improved survival (ILCOR, 2019; ILCOR, 2022).

Operationally, this means that in cases where the reversible cause cannot be managed in the field, performing a single rhythm interpretation to confirm a non-shockable rhythm before transport is consistent with guideline intent. Once transport is initiated, the focus should shift to maximizing perfusion and oxygen delivery while minimizing pauses in compressions. Additional rhythm checks may be considered only when there is a plausible likelihood of rhythm change that could alter prehospital management, such as a toxin-induced arrest where defibrillation remains potentially effective.

References
American Heart Association. (2020). Part 3: Adult Basic and Advanced Life Support (2020 AHA Guidelines for CPR & ECC). Circulation.
International Liaison Committee on Resuscitation. (2019). Executive Summary: 2020 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science With Treatment Recommendations. Resuscitation.
International Liaison Committee on Resuscitation. (2022). Impact of transport on CPR quality: CoSTR BLS 1509a.