IMPORTANCE: Neurologically intact survival after out-of-hospital cardiac arrest (OHCA) has been increasing in Japan. However, associations between increased prehospital care, including bystander interventions and increases in survival, have not been well estimated.
OBJECTIVE: To estimate the associations between bystander interventions and changes in neurologically intact survival among patients with OHCA in Japan.
DESIGN, SETTING, AND PARTICIPANTS: Retrospective descriptive study using data from Japan’s nationwide OHCA registry, which started in January 2005. The registry includes all patients with OHCA transported to the hospital by emergency medical services (EMS) and recorded patients’ characteristics, prehospital interventions, and outcomes. Participants were 167 912 patients with bystander-witnessed OHCA of presumed cardiac origin in the registry between January 2005 and December 2012.
EXPOSURES: Prehospital interventions by bystander, including defibrillation using public-access automated external defibrillators and chest compression.
MAIN OUTCOMES AND MEASURES: Neurologically intact survival was defined as Glasgow-Pittsburgh cerebral performance category score 1 or 2 and overall performance category scores 1 or 2 at 1 month or at discharge. The association between the interventions and neurologically intact survival was evaluated.
I wrote at the Upshot some time ago about how Advanced Life Support (ALS) isn’t really proven to be better than Basic Life Support (BLS). In fact, it might be worse. But that doesn’t mean that the components of BLS don’t work. This study looked at how chest compressions and automatic defibrillators, components of BLS, are associated with outcomes when people have cardiac arrests in public.
From 2005 to 2012, the number of bystander witnessed cardiac arrests went up from 14 per 100,000 persons to 18.7 per 100,000 persons. Neurologically intact survival went up, too, from 3.3% of cases to 8.2%. At the same time, bystander chest compressions increased from 39% to 51% of cases, and bystander-only defibrillation increased from basically none to more than 2%.
After controlling for other factors, bystander chest compressions increased neurologically intact survival significantly, from 4.1% without to 8.4% with. So did bystander-only defibrillation over no defibrillation, increasing neurologically intact survival from 2.0% to 41%. You read that right.
Do you need more? There’s a SECOND article in the same journal – “Association of Bystander and First-Responder Intervention With Survival After Out-of-Hospital Cardiac Arrest in North Carolina, 2010-2013“:
Importance Out-of-hospital cardiac arrest is associated with low survival, but early cardiopulmonary resuscitation (CPR) and defibrillation can improve outcomes if more widely adopted.
Objective To examine temporal changes in bystander and first-responder resuscitation efforts before arrival of the emergency medical services (EMS) following statewide initiatives to improve bystander and first-responder efforts in North Carolina from 2010-2013 and to examine the association between bystander and first-responder resuscitation efforts and survival and neurological outcome.
Design, Settings, and Participants We studied 4961 patients with out-of-hospital cardiac arrest for whom resuscitation was attempted and who were identified through the Cardiac Arrest Registry to Enhance Survival (2010–2013). First responders were dispatched police officers, firefighters, rescue squad, or life-saving crew trained to perform basic life support until arrival of the EMS.
Exposures Statewide initiatives to improve bystander and first-responder interventions included training members of the general population in CPR and in use of automated external defibrillators (AEDs), training first responders in team-based CPR including AED use and high-performance CPR, and training dispatch centers in recognition of cardiac arrest.
Main Outcomes and Measures The proportion of bystander and first-responder resuscitation efforts, including the combination of efforts between bystanders and first responders, from 2010 through 2013 and the association between these resuscitation efforts and survival and neurological outcome.
Here’s the take-home message from this study. . Survival following EMS-initiated CPR and defibrillation was 15.2%, but survival from bystander-initiated CPR and defibrillation was higher, at 33.6%.
We’re not going to get an RCT here, likely. We can’t randomize people to get either bystander help or none. Ain’t gonna happen. So we have to rely on what we can do. These studies are a good start. From the accompanying editorial (emphasis mine):
The Institute of Medicine has released a report that describes multiple steps to improve outcomes after cardiac arrest. Key recommendations of this report include simple, sustainable high quality efforts to measure and improve the process and outcome of care, as well as increased training of EMS personnel and leadership and funding for resuscitation research. The current studies by Malta Hansen et al and by Nakahara et al demonstrate the potential benefit these changes can have on resuscitation outcomes. Lay persons can improve outcomes after cardiac arrest in their community by participating in their system of care as well as supporting increased measurement and resuscitation research.
That last sentence is the one we need to keep hammering home.