Bystander CPR Ups Late Cardiac Arrest Survival, Brain Function

Liam Davenport

May 08, 2017

AALBORG, DENMARK — Among 30-day adult survivors of out-of-hospital cardiac arrest, those who received bystander cardiopulmonary resuscitation (CPR) showed significantly lower all-cause mortality at 1 year than those who did not, especially if the intervention included defibrillation, concluded a study based on numbers from the Danish Cardiac Arrest Registry[1].

The intervention was also associated with significantly lower risk of anoxic brain damage or nursing-home admission for the 2855 30-day survivors, a fraction of the >40,000 cases of out-of-hospital arrest in the nationwide registry from 2001 to 2012, in the analysis published in the May 4, 2017 issue of the New England Journal of Medicine.

Adjusted risks with bystander CPR fell a significant 38% (P<0.001) for brain damage or nursing-home admission, 30% (P=0.04) for death from any cause, and 33% (P<0.001) for the composite of brain damage, nursing-home admission, or death.

The corresponding reductions with bystander defibrillation were more pronounced, at 55% (P=0.01), 78% (P=0.01), and 55% (P=0.005), respectively.

About 8% of the 30-day survivors died during the 1-year follow-up, and 71% of those deaths were from presumed cardiovascular causes. In addition, 10.5% of the cohort had anoxic brain damage or were admitted to a nursing home.

There were 2084 cardiac arrests not witnessed by emergency medical services. The rate of bystander CPR performed on these patients went from 66.7% to 80.6% (P<0.001) during the study period; the rate of bystander defibrillation rose from 2.1% to 16.8% (P<0.001).

One-year Hazard Ratios* for Outcomes for 30-Day Adult Survivors of Out-of-Hospital Cardiac Arrest by Bystander Intervention

End points Bystander CPR only, HR (95% CI); P Bystander CPR + defibrillation, HR (95% CI); P
Brain damage or nursing-home admission 0.62 (0.47–0.82); <0.001 0.45 (0.24–0.84); 0.01
Death from any cause 0.70 (0.50–0.99); 0.04 0.22 (0.07–0.73); 0.01
Brain damage, nursing-home admission, or death 0.67 (053–0.84); <0.001 0.45 (0.26–0.79); 0.005
*Adjusted for age, sex, Charlson comorbidity index score, year of cardiac arrest, witnessed status, time interval, and presumed cause of cardiac arrest, for patients with vs without bystander intervention

Lead author Dr Kristian Kragholm (Aalborg University Hospital, Denmark) explained to heartwire from Medscape that during the time of the study, a number of initiatives had been undertaken in Denmark to improve those numbers, including mandatory courses in CPR both in elementary schools and when people apply for a driving license.

There is also a nationwide automatic external defibrillator (AED) registry in Denmark, he said, and all stakeholders, policymakers, and companies who purchase an AED are encouraged to register the device, its location, and hours of the day it is accessible.

This information is available via a smartphone application, and the registry is linked to emergency-dispatch centers, so that healthcare professionals working in these centers can guide bystanders to the nearest AED and help them use it, according to Kragholm.

"Our findings support these bystander initiatives, as they not only increase patient survival but they also lower the risk of nursing-home admission and brain damage, which can be markers of cerebral damage after cardiac arrest."

The registries can be used to determine how often bystanders perform CPR and defibrillate patients, he said, "and what we have observed in Denmark is really marked increases in rates of bystander CPR and bystander defibrillation, alongside these initiatives."

As he and his colleagues note in the report, the proportion of 30-day survivors among adult-out-of-hospital arrest cases over the years increased from 3.9% to 12.4%.

The study was by the Danish foundation TrygFonden and the Danish Heart Foundation. The Danish Cardiac Arrest Registry is supported by TrygFonden. Kragholm reports receiving lecture fees from Novartis Healthcare. Disclosures for the coauthors are listed in the paper.

For more from, follow us on Twitter and Facebook.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.