Brain damage, nursing home admissions lower with intervention
• by Salynn Boyles
Contributing Writer May 03, 2017
Action Points
• Bystander cardiopulmonary resuscitation and defibrillation was associated with better survival and reduced long-term disability among survivors of out-of-hospital cardiac arrest.
• Note that the study suggests systematic national efforts to improve cardiac-arrest management may result in improvements not only in survival, but also in functionally intact survival.

Bystander cardiopulmonary resuscitation (CPR) and defibrillation was associated with better survival and reduced long-term disability among survivors of out-of-hospital cardiac arrest, according to a nationwide study from Denmark.
The study included all adult, 30-day survivors of cardiac arrest occurring outside hospitals in that country from 2001 through 2012. Both anoxic brain damage and nursing home admission at 1 year following the event were significantly lower among 30-day survivors receiving bystander cardiopulmonary resuscitation or defibrillation, reported Kristian Kragholm, MD, PhD, of Aalborg University Hospital, Aalborg, and colleagues.
Brain damage, nursing home admissions, and deaths decreased during the course of the observation period, concurrent with significant increases in bystander use of CPR and defibrillation, they wrote in the New England Journal of Medicine.
Kragholm’s group noted that while bystander intervention has been shown to increase cardiac arrest survival rates in several studies, the newly published research is among the first to confirm an association between bystander CPR and defibrillation and improved functional outcomes.
During the period studied, Denmark implemented nationwide initiatives designed to increase bystander intervention in cardiac arrest, including mandatory and voluntary CPR training, widespread dissemination of automated external defibrillators, and other measures.
“Altogether, the changes in functional outcomes that were observed after these initiatives were implemented suggest that systematic national efforts to improve cardiac-arrest management may result in improvements not only in survival, but also in functionally intact survival,” the researchers wrote.
They linked nationwide data on out-of-hospital cardiac arrests in Denmark to functional outcome data, and reported the 1-year risks of anoxic brain damage or nursing home admission, and of death from any cause among patients who survived to day 30 after an out-of-hospital cardiac arrest.
Cox regression was used to assess associations between bystander intervention and outcome hazards, with adjustment for year of cardiac arrest, age, sex, Charlson comorbidity index score, cause of cardiac arrest, witnessed status, and time between recognition of cardiac arrest and EMS rhythm analysis. Sensitivity analyses of absolute risks were also performed.
Among the 2,855 patients who were 30-day survivors of an out-of-hospital cardiac arrest during the decade, a total of 10.5% had brain damage or were admitted to a nursing home and 9.7% died during the 1-year follow-up period.
Among the 2,084 patients who had cardiac arrests that were not witnessed by emergency medical services (EMS) personnel, the rate of bystander CPR increased from 66.7% to 80.6% (P<0.001) between 2001 and 2012.
Also, the rate of bystander defibrillation increased from 2.1% to 16.8% (P<0.001) during the period.
The rate of brain damage or nursing home admission decreased from 10.0% to 7.6% (P<0.001), and all-cause mortality decreased from 18.0% to 7.9% (P=0.002).
In adjusted analyses, bystander CPR was associated with a risk of brain damage or nursing home admission that was significantly lower than that associated with no bystander resuscitation (hazard ratio 0.62, 95% CI 0.47-0.82), as well as a lower risk of death from any cause (HR 0.70, 95% CI 0.50-0.99) and a lower risk of the composite endpoint of brain damage, nursing home admission, or death (HR 0.67, 95% CI 0.53-0.84).
The risks of these outcomes were even lower among patients who received bystander defibrillation as compared with no bystander resuscitation.
EMS-witnessed cardiac arrest was associated with significantly higher all-cause mortality among 30-day survivors, which may be due to the increased average age and comorbidity scores in this group.
“In most cases, these patients did not have a sudden onset of cardiac arrest but instead had a cardiac arrest during gradual worsening of an acute medical condition for which EMS had already been activated,” the researchers wrote.
Study limitations included the observational design and a lack of information on the duration of cardiac arrest.