Abstract 9499: Prehospital Factors Associated With Cardiopulmonary Resuscitation Performance in Out-of-Hospital Cardiac Arrests

Abstract

Introduction: Although high quality cardiopulmonary resuscitation (CPR) has been associated with improvements in survival from cardiac arrest, little is known about the arrest factors that influence CPR performance. This study examined the association between CPR performance and patient and arrest factors in out-of-hospital cardiac arrest (OHCA). Methods: A retrospective observational study using data from a statewide cardiac arrest registry in Victoria, Australia. The study included 2,408 adult, medical OHCA patients who arrested between 11 February 2019 and 10 February 2021. Fractional and logistic regression models were used to analyse factors associated with CPR performance outcomes, including the proportion of compressions at target depth and target rate and a compression fraction ≥90%. Results: The median proportion of compressions at target depth and target rate were 80% (interquartile range [IQR] 58, 92.5) and 62% (IQR 40, 79), respectively, and 70% achieved a compression fraction ≥90%. After multivariable adjustment, achieving a compression depth in the target range was associated with female sex (OR 1.14 [95% CI: 1.02, 1.28]), patient weight (per 10 kg increase, OR 1.08 [95% CI: 1.05, 1.12]), aged care facility location (OR 0.74 [95% CI: 0.58, 0.94]), fire-fighter presence (OR 1.29 [95% CI: 1.14, 1.46]), resuscitation duration (per 5 min increase, OR 1.08 [95% CI: 1.06, 1.10]) and number of rescuers (per 1 person increase, OR 1.06 [95% CI: 1.03, 1.09]). Achieving compressions within target rate were associated with public location (OR 0.81 [95% CI: 0.72, 0.91]) and fire-fighter presence (OR 1.12 [95% CI: 1.02, 1.24]). Achieving a compression fraction ≥90% was associated with female sex (OR 0.75 [95% CI: 0.62, 0.91]), arrests witnessed by emergency services (OR 0.44 [95% CI: 0.32, 0.61]), initial shockable rhythms (OR 0.66 [95% CI: 0.53, 0.81]), fire-fighter presence (OR 1.24 [95% CI: 1.01, 1.54]) and resuscitation duration (per 5 min increase, OR 1.05 [95% CI: 1.02, 1.08]). Conclusion: This study demonstrates that several prehospital factors that are associated with CPR performance which may help inform operational strategies to improve OHCA outcomes.