CPR Quality During OHCA Transport Sheldon Cheskes, MD CCFP(EM) FCFP Medical Director, Sunnybrook Centre for Prehospital Medicine Associate Professor, Division of Emergency Medicine, University of Toronto Scientist, Li Ka Shing Knowledge Institute, St. Michael s Hospital Co-Principal Investigator, Toronto RescuNet, Resuscitation Outcomes Consortium Disclosure Financial Disclosure: Zoll Medical Honorarium for Speaking on CPR Quality, Physio-Control sponsorship on CPR Quality AstraZeneca: Brilinta Advisory Board Unlabeled/Unapproved Uses Disclosure: None Conflicts of Interest: None Co-authors Cathy Zhan Adam Byers Ian Drennan Steve Lin P. Richard Verbeek Jason Buick Steve Brooks Dennis Ko Ahamed Taher Laurie J. Morrison 1
Background Previous studies have demonstrated significant relationships between cardiopulmonary resuscitation (CPR) quality metrics and survival from out-of-hospital cardiac arrest (OHCA) The quality of CPR provided during resuscitation may be significantly impacted by the location of resuscitation (pre-hospital vs. transport vs. in-hospital) Background Multiple small observational studies as well as mannequin studies suggest CPR quality deteriorates during the transport phase of OHCA resuscitation These studies lack both the power and sample size to adequately answer the question of transport CPR quality and took place prior to the current focus on high-quality CPR Objective To determine the impact of CPR location on CPR quality metrics during out-of-hospital cardiac arrest 2
Methods Retrospective cohort study of prospectively collected data from the Toronto RescuNET Epistry cardiac arrest database Analysis of defibrillator files and CPR quality data from all treated adult OHCA occurring over a 39 month period beginning January 1, 2013 Methods Included OHCA patients who underwent resuscitation by EMS and had manual CPR quality metric data for both scene and transport phases of the resuscitation Based on 2010 American Heart Association Guidelines, high quality CPR was defined as chest compression fraction (CCF) > 0.70, compression rate > 100/min and compression depth > 5.0 cm Methods Primary Analysis: comparison of the proportion of patients who received high quality CPR (defined as meeting all 3 CPR quality benchmarks) between resuscitation locations using McNemar s Z test with two-sided equality Secondary Analysis: comparison of scene and transport CPR quality metrics for each patient using a Wilcoxon rank-sum paired-samples test Sensitivity analysis performed to assess differences in CPR quality between scene, transport and patient egress from home (defined as CPR 5 minutes prior to depart scene) 3
Table 1 Descriptive Statistics of All Patients in Study Population CPR Quality from Both Scene and Transport Age (mean ± SD) 66.8 ± 17.0 Gender (male %) 585 (69.5%) Bystander CPR (%) 304 (43.4%) Witnessed by EMS or Bystander (%) 544 (64.6%) Location of Arrest (public %) 203 (24.1%) Initial Rhythm - VF/VT/Shockable (%) 250 (29.7%) Re-arrest (%) 238 (28.3%) Response Time (min, mean ± SD) * 6.4 ± 2.7 Scene Time (min, mean ± SD) 30.3 ± 11.2 Transport Time (min, mean ± SD) 7.2 ± 3.8 * SD = standard deviation; Episodes witnessed by EMS excluded Table 2 Primary Analysis * CPR Metric * Scene Phase (%) Transport Phase (%) p Value # of Cases Meeting All 3 CPR Benchmarks 386 (45.80%) 358 (42.50%) <.17 # of Cases Not Meeting All 3 CPR Benchmarks 456 (54.20%) 484 (57.50%) Meeting 0 Benchmarks 10 (2.20%) 14 (2.90%) Meeting 1 Benchmark 67 (14.70%) 124 (25.60%) Meeting 2 Benchmarks 379 (83.10%) 346 (71.50%) Rate Not Meeting Benchmark 184 (40.40%) 351 (72.50%) <.01 Fraction Not Meeting Benchmark 49 (10.80%) 26 (5.40%) <.01 Depth Not Meeting Benchmark 310 (68.00%) 259 (53.50%) <.01 * McNemar s Z test with two sided equality 4
Table 3 Comparison of Individual CPR Quality Metrics between Scene and Transport Scene Phase Median (IQR*) Transport Phase Median (IQR) CPR Duration (minutes) 23 (14) 7 (4) p Value # of CPR Minutes with Data 21 (14) 5 (5) Proportion of CPR Minutes with Data 90% (10) 80% (10) < 0.01 Compression Rate 105.7 (12.0) 102.0 (12.5) < 0.01 Chest Compression Fraction 0.87 (0.11) 0.95 (0.08) < 0.01 Compression Depth 5.33 (1.39) 5.56 (1.49) < 0.01 *IQR = interquartile range, Wilcoxon rank-sum test Table 4 Comparison of CPR Quality between Scene, Egress and Transport Phases Scene (Pre-Egress) Phase Median (IQR*) (N = 759) Egress Phase Median (IQR) N = 759) Transport Phase Median (IQR) (N = 759) p Value (adjusting for subject) # of CPR Minutes with Data 17 (13) 5 (0) 5 (5) < 0.01 Compression Rate 106.00 (12.50) 106.00 (14.00) 102.00 (12.00) < 0.01 Chest Compression Fraction 0.86 (0.12) 0.87 (0.20) 0.95 (0.08) < 0.01 Compression Depth 5.30 (1.48) 5.54 (1.63) 5.55 (1.48) < 0.01 *IQR = interquartile range Discussion High quality CPR performed both on scene and during transport in similar proportions regardless of 2010 or 2015 AHA Guideline use (24.8% vs 21.4%; 3.4; 95% CI: -1.4, 8.1, p=0.09) Individual CPR metrics met or exceeded AHA Guideline recommendations regardless of location CPR quality during egress did not substantially deteriorate in study cohort 5
Why Was CPR Quality During Transport So High? Site heavily monitored as part of ROC RCTs for CPR quality Potential Hawthorne effect Ongoing feedback of CPR quality in real-time (CPR feedback activated on defibs) Post resuscitation feedback on CPR quality Why Was CPR Quality During Transport So High? Amount of CPR data on transport significantly less than on scene More personnel available during transport than initially on scene All advanced interventions completed by time of transport, minimizing interruptions in CPR System protocol allows only one stop en route for defibrillation so continuous CPR performed in transport Limitations Shorter duration of CPR quality data for transport as such results may not be applicable to rural systems Focus on high quality CPR in agencies may not make findings generalizable Employed 2010 as opposed to 2015 Guidelines but sensitivity analysis yielded similar results Study was focused on CPR quality alone, not safety 6
Conclusions High quality CPR metrics were identified in both locations (scene and transport) of resuscitation and exceeded current CPR quality benchmarks High quality CPR involving simultaneous provision of benchmark focused CPR metrics remains a challenge for even well trained EMS systems and must be improved Our results suggest that high quality manual compressions can be performed by well-trained EMS systems regardless of location Acknowledgement Thank You! 7