Reply to: On the “2-minute rule”

To the Editor,

We thank Stewart for his thoughtful comments¹ regarding our article “Rethinking the 2-minute rule in adult basic life support cardiopulmonary resuscitation”.² We agree that the rationale for a fixed 2-min interval, originally designed to mitigate AED-related pauses, does not necessarily apply to manual defibrillation. As pointed out, manual defibrillators offer the opportunity to shorten chest compression pause durations for rhythm analysis and shorter peri-shock pauses, in particular for in-hospital cardiac arrest.³ However, we would like to highlight several practical considerations.

First, manual defibrillation indeed allows clinicians to overcome some limitations of automated technology and could enable more personalized algorithms. This flexibility may facilitate earlier shocks and adaptive strategies, as Stewart suggests.¹ Nevertheless, manual defibrillation requires advanced training and regular practice. It is important to keep in consideration that most of the teams involved in cardiac arrest care are with limited exposure to cardiac arrest scenarios and may easily lose track of analysis timing, inadvertently introducing additional delays between shocks. Manual defibrillators are more subject to human factor interference and considerable task-specific differences in the usability of manual defibrillators have been observed.⁴

Second, manual defibrillators are generally reserved for healthcare professionals, and their deployment can involve significant delays, especially in out-of-hospital settings. Our article focused on the basic life support algorithm and does not apply to more experienced teams following advanced life support guidelines. In contrast, AEDs remain the only devices accessible to the general public and first responders, who are often rarely confronted with cardiac arrest. For these rescuers, a simplified, standardized algorithm remains essential to ensure timely intervention and minimize cognitive load.

Third, technology is already available, decrease in chest compression pause durations for rhythm analysis and shorter time spent in ventricular fibrillation have been observed.5, 6 Data are still lacking on the impact on clinical outcomes.

Finally, while we support the principle of differentiating algorithms for AED and manual defibrillation, any modification must balance potential benefits with the realities of training, device availability, and system organization. Future research should explore whether adaptive strategies, such as stacked shocks or shorter CPR intervals, improve outcomes when manual defibrillation is feasible, without compromising safety in less controlled environments.

CRediT authorship contribution statement

Guillaume Debaty: Conceptualization, Writing – original draft. Emma Menant: Conceptualization, Writing – review & editing. Xavier Jouven: Conceptualization, Writing – review & editing.

Declaration of competing interest

The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Emma Menant reports a relationship with SCHILLER Médical, Wissembourg, France that includes: receiving research support. Xavier Jouven reports a relationship with SCHILLER Médical, Wissembourg, France that includes: receiving funds for scientific consulting.