Association Between Prompt Defibrillation and Epinephrine Treatment With Long Term Survival After In-Hospital Cardiac Arrest
Prior studies have reported higher in-hospital survival with prompt defibrillation and epinephrine treatment in patients suffering in-hospital cardiac arrest (IHCA). Whether this survival benefit persists after discharge is unknown.Methods—
We linked data from a national IHCA registry with Medicare files and identified 36,961 patients aged ≥65 years with an IHCA at 517 hospitals between 2000 and 2011. Patients with IHCA due to pulseless ventricular tachycardia (VT) or ventricular fibrillation (VF) were stratified by prompt (≤2 min) vs. delayed (>2 min) defibrillation, whereas patients with IHCA due to asystole or pulseless electrical activity (PEA) were stratified by prompt (≤ 5 min) vs. delayed (>5 min) epinephrine treatment. The association between prompt treatment and long-term survival for each rhythm type was assessed using multivariable hierarchical modified Poisson regression models.Results—
Of 8119 patients with an IHCA due to VT/VF, the rate of 1-year survival was higher in those treated with prompt defibrillation than with delayed defibrillation (25.7% [1466/5714] vs. 15.5% [373/2405]; adjusted RR, 1.49 [1.32, 1.69]; p<0.0001). This survival advantage persisted at 3 years (19.1% vs. 11.0%; adjusted RR of 1.45; 95% CI: 1.23, 1.69; p<0.0001) and at 5 years (14.7% vs. 7.9%; adjusted RR of 1.50, 95% CI: 1.22, 1.83; p<0.0001). Of 28,842 patients with an IHCA due to asystole/PEA, the rate of 1-year survival with prompt epinephrine treatment was higher than with delayed treatment (5.4% [1341/24,885] vs. 4.3% [168/3957]; adjusted RR, 1.20 [1.02, 1.41]; p=0.02), but this survival benefit was no longer present at 3 years (3.5% vs. 2.9%; adjusted RR, 1.17 [0.95, 1.45]; p=0.15) and at 5 years (2.3% vs. 1.9%; adjusted RR. 1.18 [0.88, 1.58]; p=0.27).Conclusions—
Prompt defibrillation for IHCA due to VT/VF was associated with higher rates of long-term survival throughout 5 years of follow-up, whereas prompt epinephrine treatment for asystole/PEA was associated with greater survival at 1 year, but not at 3 or 5 years. By quantifying the greater survival associated with timely defibrillation and epinephrine administration, these findings provide important insights on the durability of survival benefits for two process-of-care measures in current resuscitation guidelines.