Effect of Admission Day and Time on Patient Outcome: An Observational Study in Intensive Care Units of a Tertiary Care Hospital in India

Background:The current study aimed to assess any association between intensive care unit (ICU) and hospital outcomes with ICU admission timings of critically ill patients.Methods: Retrospective observational single-center study involving all adult admissions.Each patient admission was categorized in "afterhours" (08:00 p.m.-07:59 a.m.), or "normal-hours" (08:00 a.m.-07:59 p.m.), "Weekday" (Monday-Saturday), or "Weekend" (Sunday), "Same day" (admission directly to ICU) or "other day admission" (admission to ICU after a hospital stay of ≥24 hours).Intensive care unit and hospital mortality, length of stay (LOS), and ICU readmission were assessed for any association with different admission timings.Results: Among 3,029 patients, 54.2% (1,668) were male, with mean age 66.49 (SD ± 15.69) years, mean acute physiology and chronic health evaluation-IV (APACHE-IV) score 55.5 (SD ± 26.3).Around 86.1% of admission occurred during weekdays, 13.9% on weekends, 57.4% normalhours, 42.6% after-hours, 66.3% same day and 33.7% other day admission.Intensive care unit and hospital mortality were 10.8 and 14.2% respectively.Neither ICU nor hospital mortality were significantly different among patients admitted normal vs after-hours (p = 0.32, 0.23), and weekdays vs weekends (p = 0.09, 0.93), nor was ICU LOS (p = 0.21, 0.74).Intensive care unit and hospital mortality (p = 0.001), DORB (p = 0.001), hospital LOS (p = 0.001), and readmission to ICU (p = 0.001) were significantly higher in the other day admission group compared to same-day admission.In a multivariate regression analysis age, APACHE IV score along with other day admission to ICU did have a significant effect on both ICU and hospital mortality.Conclusion: Intensive care unit and hospital mortality and LOS did not differ significantly with hours or days of ICU admission though they were significantly higher in other day admission groups.