Karlsson, Lena I M2; Wissenberg, Mads2; Fosbøl, Emil L2; Hansen, Carolina Malta2; Lippert, Freddy K3; Bagai, Akshay2; McNally, Bryan2; Granger, Christopher B2; Christensen, Erika Frischknecht2; Folke, Fredrik2; Rajan, Shahzleen2; Weeke, Peter2; Nielsen, Søren L2; Køber, Lars3; Gislason, Gunnar H2; Torp-Pedersen, Christian2
1 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet2 unknown3 Department of Clinical Medicine, Department of Clinical Medicine, Faculty of Health and Medical Sciences, Københavns Universitet
A nationwide study in Denmark
AIM: To investigate diurnal variations in incidence and outcomes following out-of-hospital cardiac arrest (OHCA). METHODS: OHCA of presumed cardiac etiology were identified through the nationwide Danish Cardiac Arrest Registry (2001-2010). Time of day was divided into three time periods: daytime 07.00-14.59; evening 15.00-22.59; and nighttime 23.00-06.59. RESULTS: We identified 18,929 OHCA patients, aged ≥18 years. The median age was 72 years (IQR 62-80) and the majority were male (67.5%). OHCA occurrence varied across time periods, with 43.9%, 35.7% and 20.6% occurring during daytime, evening and nighttime, respectively. Nighttime patients were more likely to have: severe comorbidity (i.e. COPD), arrest in private home (87.2% vs. 69.0% and 73.0% daytime and evening, respectively), non-witnessed arrest (51.2% vs. 48.4% and 43.7%), no bystander CPR (75.9% vs. 68.4% and 66.1%), longer time interval from recognition of OHCA to rhythm analysis (12 min vs. 11 min and 11 min), and non-shockable heart rhythm (80.1% vs. 70.3% and 69.4%), all p<0.0001. Nighttime patients were less likely to achieve return of spontaneous circulation on arrival at the hospital (7.5% vs. 14.8% and 15.1%) and 1-year survival (2.8% vs. 7.2% and 7.1%), p<0.0001. Overall, the lower 1-year survival rate persisted after adjusting for patient-related and cardiac-arrest related characteristics mentioned above (OR 0.47, 95%CI 0.37-0.59; OR 0.51, 95%CI 0.40-0.65, compared to daytime and evening, respectively). CONCLUSIONS: We found nighttime patients to have a lower survival compared to daytime and evening that persisted when adjusting for patient-related and cardiac-arrest related characteristics including comorbidities.
Resuscitation, 2014, Vol 85, Issue 9, p. 1161-1168