After-Hours Discharge from Intensive Care Increases the Risk of Readmission and Death

Abstract

Despite reports showing night discharge from an intensive care unit (ICU) is associated with increased mortality, it is unknown if this has resulted in changes in practice in recent years. Our aim was to determine prevalence, trends and effect on patient outcome of discharge timing from ICU throughout Australia and New Zealand. Two datasets from the Australian and New Zealand Intensive Care Society Adult Patient Database (ANZICS APD) were examined: 1. All submissions to the APD from 1.1.2003 to 31.12.2004 to determine contemporary practices. 2. Forty hospitals which had submitted continuous data between 1.1.2000 and 31.12.2004 to determine trends in practice over time. Outcomes investigated were hospital mortality and ICU readmission rate. Between 1.1.2003 and 31.12.2004, the ANZICS APD reported 76,690 patients discharged alive from ICU; 13,968 (18.2%) were discharged after-hours (between 1800 and 0559 hours). After-hours discharges had a higher readmission rate (6.3% vs. 5.1%; P= <0.0001) and higher mortality (8.0% vs. 5.3%; P= <0.0001). Peak readmission (8.6%) and mortality rates (9.7%) were seen in patients discharged between 0300 and 0400 hours. After-hours discharge was a predictor of mortality (odds ratio 1.42, 95% confidence interval 1.32-1.52; P= <0.0001) in multivariate analysis. Between 2000 and 2004, after-hours discharges increased (P=0.0015) with seasonal peaks during winter. The risk of death increased as the proportion of patients discharged after-hours rose. After-hours discharge from ICU is associated with increased risk of death and readmission to ICU. It has become more frequent. The risk of death increases as more after-hours discharges occur.