Aims:To identify the factors associated with good-quality bystander cardiopulmonary resuscitation (BCPR). Multiple logistic regression analysis indicated that multiple rescuers (odds ratio=2.8, 95% CI: 1.5-5.6), bystander-initiated BCPR (2.7, 1.1-7.3), non-elderly bystanders (1.9, 1.1-3.2), occurrence in the central region (2.1, 1.3-3.3) and duration of BCPR (1.1, 1.0-1.1) were associated with good-quality BCPR. Moreover, good-quality BCPR was initiated earlier after recognition/witness of cardiac arrest compared with poor-quality BCPR (3 vs. 4 min, p=0.0052). MethodsThe rate of neurologically favourable survival at one year was 2.7% and 0% in the good-quality and poor-quality groups, respectively (p=0.1357). Conclusions:The presence of multiple rescuers and bystander-initiated CPR are predominantly associated with good-quality BCPR.

Background-Dispatcher-assisted cardiopulmonary resuscitation (DA-CPR) attempts to improve the management of out-of-hospital cardiac arrest by laypersons who are unable to recognize cardiac arrest and are unfamiliar with CPR. Therefore, we investigated the sensitivity and specificity of our new DA-CPR protocol for achieving implementation of bystander CPR in out-of-hospital cardiac arrest victims not already receiving bystander CPR. Methods and Results-Since 2007, we have applied a new DA-CPR protocol that uses supplementary key words. Fire departments prospectively collected baseline data on DA-CPR from January 2009 to December 2011. DA-CPR was attempted in 2747 patients; of these, 417 (15.2%) did not experience cardiac arrest. The sensitivity and specificity of the 2007 protocol versus estimated values of the previous standard protocol were 72.9% versus 50.3% and 99.6% versus 99.8%, respectively. We identified key words that may be useful for detecting out-of-hospital cardiac arrest. Multiple logistic regression analysis revealed that the occurrence of cardiac arrest after an emergency call (odds ratio, 16.85) and placing an emergency call away from the scene of the arrest (odds ratio, 11.04) were potentially associated with failure to provide DA-CPR. Furthermore, at-home cardiac arrest (odds ratio, 1.61) and family members as bystanders (odds ratio, 1.55) were associated with bystander noncompliance with DA-CPR. No complications were reported in the 417 patients who received DA-CPR but did not have cardiac arrest. Conclusions-Our 2007 protocol is safe and highly specific and may be more sensitive than the standard protocol.Understanding the factors associated with failure of bystanders to provide DA-CPR and implementing public education are necessary to increase the benefit of DA-CPR. (Circulation. 2014;129:1751-1760.)