The Association between Discharge Delay from Intensive Care and Patient Outcomes

Rationale: ICU discharge delay occurs when a patient is considered ready to be discharged but remains in the ICU. The effect of discharge delay on patient outcomes is uncertain. Objectives: To investigate the association between discharge delay and patient outcomes including hospital mortality, readmission to ICU, and length of hospital stay after ICU discharge. Methods: Data were accessed from the Australian and New Zealand Intensive Care Society Adult Patient Database between 2011 and 2019. Descriptive analyses and hierarchical logistic and Cox proportional hazards regression were used to examine association between discharge delay and adjusted outcomes. Patients were stratified and analyzed by categories of mortality risk at ICU admission. Measurements and Main Results: The study included 1,014,540 patients from 190 ICUs: 756,131 (75%) were discharged within 6 hours of being deemed ready, with 137,042 (13%) discharged in the next 6 hours; 17,656 (2%) were delayed 48-72 hours; 31,389 (3.1%) died in hospital; and 45,899 (4.5%) patients were readmitted to ICU. Risk-adjusted mortality declined with increasing discharge delay and was lowest at 48-72 hours (adjusted odds ratio, 0.87; 95% confidence interval, 0.79-0.94). The effect was seen in patients with predicted risk of death on admission to ICU of greater than 5% (adjusted odds ratio, 0.77; 95% confidence interval, 0.70-0.84). There was a progressive reduction in adjusted odds of readmission with increasing discharge delay. Conclusions: Increasing discharge delay in ICUs is associated with reduced likelihood of mortality and ICU readmission in high-risk patients. Consideration should be given to delay the discharge of patients with high risk of death on ICU admission.