The association between duration of mechanical ventilation and survival in post cardiac arrest patients

Purpose: To assess the association between the duration of mechanical ventilation during post resuscitation care and 30-day survival after cardiac arrest. Methods: We conducted a retrospective observational study using data from two national registries. Comatose cardiac arrest patients admitted to general intensive care in Swedish hospitals between 2011 and 2016 were eligible. Based on the median duration of mechanical ventilation for patients who did not survive to hospital discharge, used as a proxy for the endurance of post resuscitation care, the hospitals were divided into four ordered groups for which association with 30-day survival was analyzed. Results: In total, 5.113 patients in 56 hospitals were included. Median duration of mechanical ventilation for patients who did not survive to hospital discharge ranged from 17 h in hospital group 1-51 hours in hospital group 4. After adjustment for baseline characteristics, 30-day survival in the entire cohort was positively and independently associated with ordered hospital group: (adjusted odds ratio (95%CI); 1.12 (1.02,1.23); p =0.02). Thus, hospitals with a longer duration of mechanical ventilation among non-survivors had better survival rate among patients admitted to ICU after a cardiac arrest. However, in a secondary analysis restricted to patients with length of stay in the intensive care unit 48 h, there was no significant association between 30-day survival and ordered hospital group. Conclusion: A tendency for longer duration of post resuscitation care in the ICU was associated with higher 30-day survival in comatose patients admitted to intensive care after cardiac arrest.