RESUMO
BACKGROUND: Variability in the duration of attempted inhospital cardiopulmonary resuscitation (CPR) is high, but the factors influencing termination of CPR efforts are unknown. METHODS AND RESULTS: We examined the association between patient and hospital characteristics and CPR duration in 45 500 victims of inhospital cardiac arrest who did not experience return of spontaneous circulation (ROSC) and who were enrolled in the Get With the Guidelines registry between 2001 and 2010. In a secondary analysis, we performed analyses in 46 168 victims of inhospital cardiac arrest who experienced ROSC. We used ordered logistic regression to identify factors associated with CPR duration. Analyses were conducted by tertile of CPR duration (tertiles: ROSC group: 2 to 7, 8 to 17, and 18 to 120 minutes; noROSC group: 2 to 16, 17 to 26, 27 to 120 minutes). In those without ROSC, younger age (aged 18 to 40 versus >65 years; odds ratio [OR] 1.81; 95% CI 1.69 to 1.95; P<0.001), female sex (OR 1.05; 95% CI 1.02 to 1.09; P=0.005), ventricular tachycardia or fibrillation (OR 1.50; 95% CI 1.42 to 1.58; P<0.001), and the need to place an invasive airway (OR 2.59; 95% CI 2.46 to 2.72; P<0.001) were associated with longer CPR duration. In those with ROSC, ventricular tachycardia or fibrillation (OR 0.89; 95% CI 0.85 to 0.93; P<0.001) and witnessed events (OR 0.87; 95% CI 0.82 to 0.91; P<0.001) were associated with shorter duration. CONCLUSIONS: Age and sex were associated with attempted CPR duration in patients who do not experience ROSC after inhospital cardiac arrest but not in those who experience ROSC. Understanding the mechanism of these interactions may help explain variability in outcomes for inhospital cardiac arrest.