Article Text

Longitudinal exploration of in situ mock code events and the performance of cardiac arrest skills
  1. Samuel Owen Clarke1,
  2. Ian M Julie1,
  3. Aubrey P Yao2,
  4. Heejung Bang3,
  5. Joseph D Barton4,
  6. Sameerah M Alsomali5,
  7. Matthew V Kiefer6,
  8. Ali Hassan Al Khulaif7,
  9. Muna Aljahany8,
  10. Sandhya Venugopal9,
  11. Aaron E Bair1
  1. 1Department of Emergency Medicine, University of California, Davis, Sacramento, California, USA
  2. 2Department of Anesthesia, University of California, Davis, Sacramento, California, USA
  3. 3Division of Biostatistics, University of California, Davis, Sacramento, California, USA
  4. 4Department of Emergency Medicine, Kaiser Permanente Antioch Medical Center, Antioch, California, USA
  5. 5Department of Emergency Medicine, King Saud Bin Abdulaziz University for Health Sciences, Riyadh, Saudi Arabia
  6. 6Emergency Medicine, St. Joseph’s Medical Center, Stockton, California, USA
  7. 7Emergency Medicine, Prince Sultan Military Medical City, Riyadh, Saudi Arabia
  8. 8Emergency Medicine, Princess Nourah Bint Abdulrahman University, Riyadh, Riyadh, Saudi Arabia
  9. 9Division of Cardiology, University of California, Davis, Sacramento, California, USA
  1. Correspondence to Dr Samuel Owen Clarke, Department of Emergency Medicine, University of California, Davis, Sacramento, CA 95616, USA; soclarke{at}


Introduction In-hospital cardiac arrest (IHCA) affects 200 000 adults in the USA each year, and resuscitative efforts are often suboptimal. The objective of this study was to determine whether a programme of ‘mock codes’ improves group-level performance of IHCA skills. Our primary outcome of interest was change in cardiopulmonary resuscitation (CPR) fraction, and the secondary outcomes of interest were time to first dose of epinephrine and time to first defibrillation. We hypothesised that a sustained programme of mock codes would translate to greater than 10% improvement in each of these core metrics over the first 3 years of the programme.

Methods 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 summarised using descriptive statistics, and repeated measures outcomes were calculated using a mixed effects model.

Results 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 6-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.

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

  • simulation
  • in situ
  • mock code
  • cardiac arrest
  • team training

Statistics from


  • Contributors SOC, IMJ, HB, APY and AEB contributed to the origination and design of this study. SOC, IMJ, APY, JDB, SMA, MVK, AHAK, MA and SV were responsible for the data collection. SOC, IMJ, HB and APY contributed to the data analysis and interpretation of the study. All the authors contributed to the writing and critical review of this manuscript.

  • Funding The efforts of HB for this study were supported in part by the National Center for Advancing Translational Sciences, National Institutes of Health, through grant number UL1 TR001860.

  • Competing interests None declared.

  • Ethics approval UC Davis Institutional Review Board.

  • Provenance and peer review Not commissioned; externally peer reviewed.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.