Duration of Resuscitation and Long-Term Outcome After In-Hospital Cardiac Arrest: A Nationwide Observational Study

BACKGROUND: Prior studies have investigated the association between duration of resuscitation and short-term outcomes following in-hospital cardiac arrest (IHCA). However, it remains unknown whether there is an association between duration of resuscitation and long-term survival and functional outcomes.

METHOD: We linked data from the Danish in-hospital cardiac arrest registry with nationwide registries and identified 8,727 patients between 2013 and 2019. Patients were stratified into four groups (A-D) according to quartiles of duration of resuscitation. Standardized average probability of outcomes was estimated using logistic regression.

RESULTS: Of 8,727 patients, 53.1% (n=4,604) achieved return of spontaneous circulation. Median age was 74 (1st-3rd quartile [Q1-Q3] 65-81 years) and 63.1% were men. Among all IHCA patients the standardized 30-day survival was 62.0% (95% CI 59.8%-64.2%) for group A (< 5 minutes), 32.7% (30.8%-34.6%) for group B (5-11 minutes), 14.4% (12.9%-15.9%) for group C (12-20 minutes) and 8.1% (7.0%-9.1%) for group D (21 minutes or more). Similarly, 1-year survival was also highest for group A (50.4%; 48.2%-52.6%) gradually decreasing to 6.6% (5.6%-7.6%) in group D. Among 30-day survivors, survival without anoxic brain damage or nursing home admission within one-year post-arrest was highest for group A (80.4%; 78.2%-82.6%), decreasing to 73.3% (70.0%-76.6%) in group B, 67.2% (61.7%-72.6%) in group C and 73.3% (66.9%-79.7%) in group D.

CONCLUSION: Shorter duration of resuscitation attempt during an IHCA is associated with higher 30-day and 1-year survival. Furthermore, we found that the majority of 30-day survivors were still alive 1-year post-arrest without anoxic brain damage or nursing home admission despite prolonged resuscitation.