title: Mortality Associated with Night and Weekend Admissions to ICU with On-Site Intensivist Coverage: Results of a Nine-Year Cohort Study (2006-2014).
abstract: BACKGROUND
  The association between mortality and time of admission to ICU has been extensively studied but remains controversial. We revaluate the impact of time of admission on ICU mortality by retrospectively investigating a recent (2006-2014) and large ICU cohort with on-site intensivist coverage.
  
  
  METHODS
  All adults (≥ 18 years) admitted to a tertiary care medical ICU were included in the study. Patients' characteristics, medical management, and mortality were prospectively collected. Patients were classified according to their admission time: week working days on- and off-hours, and weekends. ICU mortality was the primary outcome and adjusted Hazard-ratios (HR) of death were analysed by multivariate Cox model.
  
  
  RESULTS
  2,428 patients were included: age 62±18 years; male: 1,515 (62%); and median SAPSII score: 38 (27-52). Overall ICU mortality rate was 13.7%. Admissions to ICU occurred during open-hours in 680 cases (28%), during night-time working days in 1,099 cases (45%) and during weekends in 649 cases (27%). Baseline characteristics of patients were similar between groups except that patients admitted during the second part of night (00:00 to 07:59) have a significantly higher SAPS II score than others. ICU mortality was comparable between patients admitted during different time periods but was significantly higher for those admitted during the second part of the night. Multivariate analysis showed however that admission during weeknights and weekends was not associated with an increased ICU mortality as compared with open-hours admissions.
  
  
  CONCLUSIONS
  Time of admission, especially weeknight and weekend (off-hour admissions), did not influence the prognosis of ICU patients. The higher illness severity of patients admitted during the second part of the night (00:00-07:59) may explain the observed increased mortality.
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Brunot
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Liliane
authors.initials: L
authors.lastname: Landreau
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Corne
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.|School of medicine, Montpellier University, Montpellier, France.
authors.forename: Laura
authors.initials: L
authors.lastname: Platon
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Noémie
authors.initials: N
authors.lastname: Besnard
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.|School of medicine, Montpellier University, Montpellier, France.
authors.forename: Aurèle
authors.initials: A
authors.lastname: Buzançais
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Delphine
authors.initials: D
authors.lastname: Daubin
authors.affiliation: Department of Nephrology-Transplantation, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Jean Emmanuel
authors.initials: JE
authors.lastname: Serre
authors.affiliation: Department of Statistics, Lapeyronie University Hospital, Montpellier, France.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Molinari
authors.affiliation: Department of Intensive Care Medicine, Lapeyronie University Hospital, Montpellier, France.|School of medicine, Montpellier University, Montpellier, France.|PhyMedExp, Centre National de la Recherche Scientifique (CNRS 9214) - Institut National de la Santé et de la Recherche Médicale (INSERM U-1046), Montpellier University, Montpellier, France.
authors.forename: Kada
authors.initials: K
authors.lastname: Klouche
mesh_terms: D015331:Cohort Studies; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010343:Patient Admission; D010820:Physicians / Q000600:supply & distribution*; D012189:Retrospective Studies; D013997:Time Factors