Related Experiment Video
Updated: Jul 10, 2025

Ultrasonographic Assessment During Cardiopulmonary Resuscitation
Published on: October 24, 2020
Chest compression quality comparing 1-min vs 2-min rotation of rescuers wearing N95 masks
Maria J Mathew1, Pankaj Kundra2, Stalin Vinayagam2
1Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Dhanvantari Nagar, Puducherry 605006, India.
Background:
During the COVID-19 pandemic, cardiopulmonary resuscitation (CPR) performed by rescuers wearing well-sealed respirators such as N95 masks, was associated with significant reduction in the chest compression rate and depth. This was attributed to fatigue during the standard 2-min rescuer rotations. We hypothesized that in such situations, rotating rescuers every one minute, instead of the standard two minutes would improve CPR quality.
Aim:
To compare the quality of chest compressions when rescuers wearing N95 masks are rotated every one minute, instead of the standard practice of two-minute rotations.
Methods:
A randomized, controlled, crossover trial was conducted, with the approval of the institutional Ethics Committee. Medical students who volunteered as rescuers were trained to perform high-quality chest compressions on a manikin, and then randomly allocated into pairs. Each pair was randomized to one of two trial groups viz. one-minute rotations crossed-over to two-minute rotations; and vice versa. Thus, each pair performed CPR with one-minute rotations, as well as two-minute rotations Each CPR session included chest compressions for a duration of 12 min. The outcome parameters included CPR quality, compression depth, compression rate, and chest compression fraction. Rescuer fatigue was measured before and after each study session using the modified Borg scale.
Results:
Fifty-six participants completed the study. The overall CPR quality was statistically similar in the study arms (median 88% vs. 81%, p = 0.09). However, the minute-to-minute inter-arm comparison revealed significantly lower CPR quality in the 2-min rotation arm, at the end of minutes 4, 6, 8, 10 and 12 (respective p-values 0.03, 0.001, 0.008, 0.02, 0.002). A similar trend was observed in compression depth also. Rescuer fatigue score was significantly less with 1-min rotations compared to 2-min rotations (p < 0.001). Rescuer vital signs and cardiorespiratory parameters were not different with the two types of rotations.
Conclusion:
During CPR performed by rescuers wearing N95 masks, the quality of CPR appears to be superior with rescuers rotating at 1-min instead of 2-min intervals. More frequent rotation was also associated with less rescuer fatigue.
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