Usefulness of a metronome to improve quality of chest compressions during cardiopulmonary resuscitation

Metronome use improves achievement of a target compression rate in out-of-hospital cardiac arrest: A retrospective analysis

Aim

The aim of this study was to evaluate chest compression rates (CCR) with and without the use of a metronome during treatment of out-of-hospital cardiac arrest (OHCA).

Methods

We performed a retrospective cohort investigation of non-traumatic OHCA cases treated by Seattle Fire Department from January 1, 2013, to December 31, 2019. The exposure was a metronome running during CPR at a rate of 110 beats per minute. The primary outcome was the median CCR for all periods of CPR with a metronome compared to periods without a metronome.

Results

We included 2,132 OHCA cases with 32,776 minutes of CPR data; 15,667 (48%) minutes had no metronome use, and 17,109 (52%) minutes had a metronome used. Without a metronome, the median CCR was 112.8 per minute with an interquartile range of 108.4 - 119.1, and 27% of minutes were above 120 or less than 100. With a metronome, the median CCR was 110.5 per minute with an interquartile range of 110.0-112.0, and less than 4% of minutes were above 120 or less than 100. The compression rate was 109, 110, or 111 in 62% of minutes with a metronome compared to 18% of minutes with no metronome.

Conclusion

The use of a metronome during CPR resulted in increased compliance to a predetermined compression rate. Metronomes are a simple tool that improves achievement of a target compression rate with little variance from that target.

The impact of a smartphone-based cognitive aid on clinical performance during cardiac arrest simulations: A randomized controlled trial

Objectives

In-hospital cardiac arrests are common and associated with high mortality. Smartphone applications offer quick access to algorithms and timers but often lack real-time guidance. This study assesses the impact of the Code Blue Leader application on the performance of providers leading cardiac arrest simulations.

Methods

This open-label randomized controlled trial included Advanced Cardiac Life Support (ACLS)-trained medical doctors (MD) and registered nurses (RN). Participants were randomized to lead the same ACLS simulation with or without the app. The primary outcome, "performance score," was assessed by a trained rater using a validated ACLS scoring system. Secondary outcomes included percentage of critical actions performed, number of incorrect actions, and chest compression fraction (percentage of time spent performing chest compressions). A sample size of 30 participants was calculated to detect a difference of 20% at the 0.05 alpha level with 90% power.

Results

Fifteen MDs and 15 RNs underwent stratified randomization. The median (interquartile range) performance score in the app group was 95.3% (93.0%-100.0%) compared to 81.4% (60.5%-88.4%) in the control group, demonstrating an effect size of r = 0.69 (Z = -3.78, r = 0.69, p = 0.0002). The percentage of critical actions performed in the app group was 100% (96.2%-100.0%) compared to 85.0% (74.1%-92.4%) in the control group. The number of incorrect actions performed in the app group was 1 (1) compared to 4 (3-5) in the control group. Chest compression fraction in the app group was 75.5% (73.0%-84.0%) compared to 75.0% (72.0%-85.0%) in the control group.

Conclusions

The Code Blue Leader smartphone app significantly improved the performance of ACLS-trained providers in cardiac arrest simulations.

Basic life support and systems saving lives

PURPOSE OF REVIEW

To describe recent science in basic life support (BLS) after cardiac arrest and how evolving knowledge in resuscitation is changing current guidelines and practices.

RECENT FINDINGS

The core elements of BLS have remained mostly unchanged since 2005 when Cardiopulmonary Resuscitation recommendations were changed from 2 ventilations to 15 compressions and up to three stacked shocks for shockable rhythms, to 30 compressions to 2 ventilations and single shocks. Since 2010, basic life support has largely focused on the importance of providing high-quality CPR for professional and lay rescuers alike. The most recent resuscitation updates has seen an increased focus on the systems perspective. The 'Systems Saving Lives' concept emphasizes the interconnection between community and Emergency Medical Services (EMS). The main changes in current resuscitation practice are within three important basic life support domains: recognition of cardiac arrest, interaction between rescuers and EMS and improving resuscitation quality.

SUMMARY

This review highlights the importance of strengthening both community and emergency medical services efforts to improve outcomes in cardiac arrest. Strategies that enhance the communication and collaboration between lay rescuers and professional resuscitation systems are important new avenues to pursue in developing systems that save more lives.