Off-Hours Intensive Care Unit Transfer Is Associated With Increased Mortality and Failure to Rescue

Cardiac postoperative intensive care unit (ICU) beds are a limited resource, and when a patient no longer requires this level of care they are quickly transferred out. We hypothesized that complications and ICU readmission increased when transfer occurred during off-hours compared with regular work hours.

From 2010 to 2021, patients who underwent a Society of Thoracic Surgeons index operation at a single center were assigned a group based on their ICU transfer time, defined as when they physically arrived on the acute care floor. Patients were stratified into off-hours vs regular hours by their transfer time. Off-hours was defined as 9 pm to 5 am. Risk-adjusted multivariable logistic regression analyzed the association of ICU readmission, postoperative complications, operative mortality, and failure to rescue by group.

The cohort included 5951 patients (off-hours n = 292 [4.9%], regular-hours n = 5659 [95.1%]). Patients in the off-hours group had significantly greater odds of risk-adjusted ICU readmission (odds ratio 1.99, 95% CI 1.25-3.04, P < .002) and mortality (odds ratio 3.88, 95% CI 2.27-6.33, P < .001). In the major complications subgroup (Off-hours n = 55, Regular-hours n = 603), Off-hours transfer was associated with increased mortality (failure to rescue) (odds ratio 3.05, 95% CI 1.58-5.69, P = .001).

Off-hours ICU to floor transfer was associated with increased postoperative complications, ICU readmission, and mortality, suggesting that the timing of ICU transfer may impact outcomes. This elucidates targets for quality and process improvement for our center and others facing the same resource constraints.