In-hospital factors associated with improved outcome after out-of-hospital cardiac arrest. A comparison between four regions in Norway

Abstract

Introduction: While pre-hospital factors related to outcome after out-of-hospital cardiac arrest (OHCA) are well known, little is known about possible in-hospitals factors related to outcome. Hypothesis: Some in-hospital factors are associated with outcome in terms of survival. Material and methods: An historical cohort observational study of all patients admitted to hospital with a spontaneous circulation after OHCA due to a cardiac cause in four different regions in Norway 1995–1999: Oslo, Akershus, Østfold and Stavanger. Results: In Oslo, Akershus, Østfold and Stavanger 98, 84, 91 and 186 patients were included, respectively. Hospital mortality was higher in Oslo (66%) and Akershus (64%) than in Østfold (56%) and Stavanger (44%), P=0.002. By multivariate analysis the following pre-arrest and pre-hospital factors were associated with in-hospital survival: age ≤71 years, better pre-arrest overall performance, a call-receipt-start CPR interval ≤1 min, and no use of adrenaline (epinephrine). The in-hospital factors associated with survival were: no seizures, base excess >−3.5 mmol l −1, body temperature ≤37.8 °C, and serum glucose ≤10.6 mmol l −1 1–24 h after admittance with OR (95% CI) 2.72 (1.09–8.82, P=0.033), 1.12 (1.02–1.23, P=0.016), 2.67 (1.17–6.20, P=0.019) and 2.50 (1.11–5.65, P=0.028), respectively. Pre-arrest overall function, whether adrenaline was used, body temperature, the occurrence of hypotensive episodes, and the degree of metabolic acidosis differed between the four regions in parallel with the in-hospital survival rates. Conclusion: Both pre-arrest, pre- and in-hospital factors were associated with in-hospital survival after OCHA. It seems important also to report in-hospital factors in outcome studies of OCHA. The design of the study precludes a conclusion on causability.