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Effect of different intervals of verbal motivation during dispatcher-assisted CPR: A randomized controlled simulation
Marcel Gehlen1, Jörg Christian Brokmann1, Rainer Röhrig2
1Department for Acute and Emergency Medicine, RWTH Aachen University, Pauwelsstrasse 30, 52074 Aachen, Germany.
Aim Of The Study:
High quality chest compressions are essential for survival and good neurological outcome in out-of-hospital cardiac arrest (OHCA). Dispatcher- assisted CPR (DA-CPR) has led to increased survival in OHCA. Recently, additional verbal motivation has shown positive effects on CPR quality. The present randomized and controlled simulation trial investigates the effect of different intervals of verbal motivation during DA-CPR.
Methods:
159 medical laypersons performed eight minutes of CPR on a simulator after randomization into one of three study groups: 1) "DA-CPR" 2) "DA-CPR + motivation every 30s" 3) "DA-CPR + motivation every 60s". Verbal motivation consisted of "push harder, do not relent. Additionally, a metronome beat was audible via telephone in the motivation groups. Primary endpoint was the difference in median chest compression depth during the eight-minute CPR compared between the study groups.
Results:
There were significant differences in median compression depth between the three study groups (p = 0.002). However, only the group "DA-CPR + motivation every 60s" showed a significant difference in compression depth compared to standard DA-CPR and was within the recommended range. Compressions with adequate depth (p = 0.009) and median compression rate (p < 0.001) were significantly elevated in both motivational groups compared to the "DA-CPR"-group.
Conclusion:
Verbal encouragement every 30 or 60 s combined with a metronome beat led to a significant augmentation of chest compression depth compared to standard DA-CPR.

