Effect of metronome rates on the quality of bag-mask ventilationduringmetronome-guided30:2cardiopulmonary resuscitation: A randomized simulation study
10.5847/wjem.j.1920-8642.2017.02.010
- Author:
Na Ung JI
1
;
Han Kuk SANG
;
Choi Cho PIL
;
Shin Hyuk DONG
Author Information
1. Department of Emergency Medicine
- Keywords:
Non-invasive ventilation;
Resuscitation;
Cardiac arrest;
Cardiopulmonary resuscitation
- From:
World Journal of Emergency Medicine
2017;8(2):136-140
- CountryChina
- Language:Chinese
-
Abstract:
BACKGROUND:Metronome guidance is a feasible and effective feedback technique to improve the quality of cardiopulmonary resuscitation (CPR). The rate of the metronome should be set between 100 to 120 ticks/minute and the speed of ventilation may have crucial effect on the quality of ventilation. We compared three different metronome rates (100, 110, 120 ticks/minute) to investigate its effect on the quality of ventilation during metronome-guided 30:2 CPR. METHODS:This is a prospective, randomized, crossover observational study using a RespiTrainer?r. To simulate 30 chest compressions, one investigator counted from 1 to 30 in cadence with the metronome rate (1 count for every 1 tick), and the participant performed 2 consecutive ventilations immediately following the counting of 30. Thirty physicians performed 5 sets of 2 consecutive (total 10) bag-mask ventilations for each metronome rate. Participants were instructed to squeeze the bag over 2 ticks (1.0 to 1.2 seconds depending on the rate of metronome) and deflate the bag over 2 ticks. The sequence of three different metronome rates was randomized. RESULTS:Mean tidal volume significantly decreased as the metronome rate was increased from 110 ticks/minute to 120 ticks/minute (343±84 mL vs. 294±90 mL, P=0.004). Peak airway pressure significantly increased as metronome rate increased from 100 ticks/minute to 110 ticks/minute (18.7 vs. 21.6 mmHg, P=0.006). CONCLUSION:In metronome-guided 30:2 CPR, a higher metronome rate may adversely affect the quality of bag-mask ventilations. In cases of cardiac arrest where adequate ventilation support is necessary, 100 ticks/minute may be better than 110 or 120 ticks/minute to deliver adequate tidal volume during audio tone guided 30:2 CPR.