[Does the time of admission to ITU affect mortality?].

Background: Among many factors that may affect mortality among ITU patients, the time of admission has been reported to play some, but ill-defined role. In the retrospective study, we analysed the time of admission, severity of the underlying disease, clinical status on admission and mortality among adult patients treated in a single ITU over a six-year period.

Methods: We compared the mortality of patients who were admitted during daytime (7 a.m. to 6:59 p.m.) and at night (7 p.m. to 6:59 a.m.). We also compared those admitted on weekdays (Monday 7 p.m. to Friday 6:59 a.m.) to those admitted during weekends (Friday 7 p.m. to Monday 7 a.m.). The patients condition was assessed using the APACHE II scale. Brain dead organ donors and readmissions were excluded from the analysis.

Results: The retrospective study involved the data of 1789 patients. Mortality was higher in patients who were admitted during the night and during weekends, when compared to daytime and weekdays, respectively. Mortality was also higher in patients admitted directly from the operating theatre after emergency surgery, but only during nights and weekends. The following independent factors in ITU mortality have been identified: length of ITU stay (OR 1.015; % CI 1.005-1.024), admission from a hospital ward (OR 1.39; 95% CI 1.04-1.86) and APACHE II score (OR 1.177; 95% CI 1.156-1.198).

Conclusion: Time of admission has not been identified as a single independent factor of ITU mortality, but admissions at night and during weekends were associated with higher mortality, probably because of emergency conditions.