Metronome app versus a mentally hummed song to improve the quality of chest compressions.

Methods: Controlled study of three clusters of medical student volunteers performing uninterrupted chest compressions for 2 minutes on a manikin. The clusters were assigned to receive no aid for compression timing (controls), to follow a metronome app set to 103 beats per minute, or to time compressions to the silent humming of ‘La Macarena’, a song with the same beat. We recorded demographic variables, delay in starting compressions, and performance quality variables using Resusci Anne Wireless SkillReporter software. The students also answered a satisfaction questionnaire. Data were analysed by intention-to-treat and per-protocol.

Results: We included 164 students. The median (interquartile range) percentage of compressions at the recommended rate of 100–120 cpm was nearly four-fold higher in the app group (91% [87%–94%]) and three-fold higher in the music group (74% [8%–98%]) than in the control group (24% [1%–92%]) (p
Conclusion: Mentally humming a familiar song with an appropriate beat, such as ‘La Macarena’, facilitates rapid initiation of cardiopulmonary resuscitation and improves the quality of compressions almost as much as following a metronome app