Conversion to shockable rhythms is associated with better outcomes in out-of-hospital cardiac arrest patients with initial asystole but not in those with pulseless electrical activity.

Pubmed ID: 27554946

Journal: Resuscitation

Publication Date: Oct. 1, 2016

Affiliation: University of Texas, Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX 75390-8579, USA.

MeSH Terms: Humans, Male, Adult, Female, Aged, Middle Aged, Survival Analysis, Heart Rate, Heart Arrest, Electric Countershock, China, Cardiopulmonary Resuscitation, Emergency Medical Services, Out-of-Hospital Cardiac Arrest, Electrophysiological Phenomena, Nervous System Diseases, Outcome Assessment, Health Care

Grants: U01 HL077887

Authors: Liao X, Luo S, Zheng R, Liao J, Liu Z, Xu J, Zhan H, Xiong Y, Idris A

Cite As: Zheng R, Luo S, Liao J, Liu Z, Xu J, Zhan H, Liao X, Xiong Y, Idris A. Conversion to shockable rhythms is associated with better outcomes in out-of-hospital cardiac arrest patients with initial asystole but not in those with pulseless electrical activity. Resuscitation 2016 Oct;107:88-93. Epub 2016 Aug 21.

Studies:

Abstract

BACKGROUND: The prognostic implication of conversion from initially non-shockable to shockable rhythms in patients with out-of-hospital cardiac arrest (OHCA) remains unclear. Our objective is to determine whether the conversion to shockable rhythms is a reliable predictor of short- and long-term outcomes both in patients who initially presented with pulseless electrical activity (PEA) and in those with asystole. METHODS: A secondary analysis was performed on non-traumatic OHCA cases ≥18 years old with PEA or asystole as initial rhythms, who were treated in the field and enrolled in the Resuscitation Outcomes Consortium (ROC) PRIMED study (clinicaltrials.gov/ct2/show/NCT00394706). We reported the characteristics and outcomes for those patients with or without shocks delivered in the field. Logistic regression analysis assessed the association of shock delivery with pre-hospital return of spontaneous circulation (ROSC), survival to hospital discharge and favorable neurological outcome as well. RESULTS: Of the 9902 included cases, 3415 (34.5%) were initially in PEA and 6487 (65.5%) were in asystole. 744 (21.8%) PEA and 1134 (17.5%) asystolic patients underwent rhythm conversions and received subsequent shocks. For asystolic patients, the adjusted odds ratios (ORs) of shock delivery for pre-hospital ROSC, survival to discharge and favorable neurological outcome were 1.862 (95%CI 1.590-2.180), 3.778 (95%CI 2.374-6.014) and 4.154 (95%CI 2.192-7.871) respectively, while for PEA patients they were 0.951 (95%CI 0.796-1.137), 1.115 (95%CI 0.720-1.726) and 1.373 (95%CI 0.790-2.385) respectively. CONCLUSIONS: Conversion to shockable rhythms was associated with better outcomes in initially asystolic OHCA patients, whereas such associations were not observed in patients initially in PEA.