Longitudinal exploration of in situ mock code events and the performance of cardiac arrest skills

In hospital cardiac arrest (IHCA) affects 200,000 adults in the United States each year, and resuscitative efforts are often suboptimal. The objective of this study was to determine whether a program of "mock codes" improves group-level performance of IHCA skills. Our primary outcome of interest was change in CPR fraction, and the secondary outcomes of interest were time to first dose of epinephrine and time to first defibrillation. We hypothesized that a sustained program of mock codes would translate to greater than 10% improvement in each of these core metrics over the first three years of the program.

We conducted mock codes in an urban teaching hospital between August, 2012 and October, 2015. Mock codes occurred on telemetry and medical/surgical units on day and night shifts. Codes were managed by unit staff and members of the hospital's "Code Blue" team, and data were recorded by trained observers. Data were summarized using descriptive statistics, and repeated measures outcomes were calculated using a mixed effects model.

Fifty-seven mock codes were included in the analysis: 42 on Medical/Surgical units and 15 on Telemetry units. CPR fraction increased by 2.9% per six-month time interval on Telemetry units, and 1.3% per time interval on Medical/Surgical units. Neither time to first epinephrine dosing nor time to defibrillation changed significantly.

While we observed a significant improvement in CPR fraction over the course of this program of mock codes, similar improvements were not observed for other key measures of cardiac arrest performance.