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CPR Compression Rotation Every One Minute Versus Two Minutes: A Randomized Cross-Over Manikin Study
Nutthapong Pechaksorn1, Veerapong Vattanavanit2
1Division of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla 90110, Thailand.
Background:
The current basic life support guidelines recommend two-minute shifts for providing chest compressions when two rescuers are performing cardiopulmonary resuscitation. However, various studies have found that rescuer fatigue can occur within one minute, coupled with a decay in the quality of chest compressions. Our aim was to compare chest compression quality metrics and rescuer fatigue between alternating rescuers in performing one- and two-minute chest compressions.
Methods:
This prospective randomized cross-over study was conducted at Songklanagarind Hospital, Hat Yai, Songkhla, Thailand. We enrolled sixth-year medical students and residents and randomly grouped them into pairs to perform 8 minutes of chest compression, utilizing both the one-minute and two-minute scenarios on a manikin. The primary end points were chest compression depth and rate. The secondary end points included rescuers' fatigue, respiratory rate, and heart rate.
Results:
One hundred four participants were recruited. Compared with participants in the two-minute group, participants in the one-minute group had significantly higher mean (standard deviation, SD) compression depth (mm) (45.8 (7.2) vs. 44.5 (7.1), P=0.01) but there was no difference in the mean (SD) rate (compressions per min) (116.1 (12.5) vs. 117.8 (12.4), P=0.08), respectively. The rescuers in the one-minute group had significantly less fatigue (P < 0.001) and change in respiratory rate (P < 0.001), but there was no difference in the change of heart rate (P=0.59) between the two groups.
Conclusion:
There were a significantly higher compression depth and lower rescuer fatigue in the 1-minute chest compression group compared with the 2-minute group. This trial is registered with TCTR20170823001.
Related Concept Videos
Cardiopulmonary Resuscitation I: Adult
Cardiopulmonary Resuscitation II: ACLS Airway Management
Crossover Experiments
Crossover designs are performed even with smaller sample sizes since the samples can act as their controls. These are better than simple randomized trials since patients are exposed to all the treatments.
Bioequivalence Experimental Study Designs: Repeated Measures, Cross-Over, Carry-Over, and Latin Square Designs

