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Background and Aims The intensive care unit (ICU) patient outcomes maybe influenced by the time of admission. We hypothesized that patients admitted to the ICU at afterhour would have more risk of death.

Methods We defined the afterhour as the period of time between 22:00 and 06:59 h. A retrospective study was conducted from January 2018 to June 2018 in ICU. The primary outcomes was ICU mortality within 30h, 30days and 7 days following admission and ICU length of stay. Other variables were included: age, sex, comorbidities, source of referral, reason for admission.

Results Of 150 admissions, 34% occurred afterhour. Most afterhour admissions were men and were referred from emergency department (67.9%). They had lower APACHII and IGSII scores. More mortality was observed for those admitted at workhour (but was not significant). Analysis showed no association between afterhour admission and hospital length of stay, length of mechanical ventilation and death within 24h, althought it was higher.

Conclusions Patients admitted afterhours were not significantly different from patients admitted at workhour. Incidence of men was more important and this can be explained by the frequency of road accidents at night and they were most commonly referred from the emergency department. We found no effect of afterhours admission on ICU mortality. It was even less than the mortality of patients admitted at workhour but death within 24 h was higher. This reflect probably a better initial management of admission at workhour. Afterhour ICU admission is not associated with higher mortality risk.