Escalation of Care: Association of Weekend and Nighttime Postoperative ICU Admission with Poor Outcomes After Gastrointestinal Cancer Surgery.

Abstract

Background: Postoperative intensive care unit (ICU) admission represents an important escalation of care after surgery. We evaluated the association between ICU admission timing and outcomes after gastrointestinal (GI) cancer surgery.

Methods: Adults undergoing GI cancer surgery with postoperative ICU care were identified in Epic Cosmos from 2016 to 2025 and classified as weekday, weekend-day, weeknight, or weekend-night admission. Outcomes included complications during the index hospitalization and within 30 days, 30-day mortality, readmission, discharge home, and prolonged length of stay (LOS ≥75th percentile of the cohort). Multivariable logistic regression evaluated associations between ICU timing and outcomes.

Results: Among 77,054 patients, 36.4% were classified as weekday, 15.4% weekend-day, 25.0% weeknight, and 23.2% weekend-night. Weekend-night classification was associated with the highest adjusted odds of 30-day mortality (aOR 1.52, 95% CI 1.42-1.63), any 30-day complication (aOR 1.76, 95% CI 1.69-1.84), and prolonged LOS (aOR 2.32, 95% CI 2.21-2.44), as well as lower odds of discharge home (aOR 0.70, 95% CI 0.67-0.73). Weeknight classification was also associated with higher odds of mortality (aOR 1.28, 95% CI 1.20-1.37), complications (aOR 1.42, 95% CI 1.36-1.48), and prolonged LOS (aOR 1.55, 95% CI 1.47-1.64).

Conclusions: Nighttime ICU classification, particularly weekend-night classification, identified patients at elevated postoperative risk after GI cancer surgery and may help inform surveillance and escalation strategies during off-hours.