title: Off-hours admission to pediatric intensive care and mortality.
abstract: BACKGROUND
  Critically ill patients are admitted to the pediatric ICU at all times, while staffing and other factors may vary by day of the week or time of day. The purpose of this study was to evaluate whether admission during off-hours is independently associated with mortality in PICUs.
  
  
  METHODS
  A retrospective cohort study of admissions of patients <18 years of age to PICUs was performed using the Virtual PICU Systems (VPS, LLC) database. "Off-hours" was defined as nighttime (7:00 pm to 6:59 am) or weekend (Saturday or Sunday any time). Mixed-effects multivariable regression was performed by using Pediatric Index of Mortality 2 (PIM2) to adjust for severity of illness. Primary outcome was death in the pediatric ICU.
  
  
  RESULTS
  Data from 234,192 admissions to 99 PICUs from January 2009 to September 2012 were included. When compared with regular weekday admissions, off-hours admissions were less likely to be elective, had a higher risk for mortality by PIM2, and had a higher observed ICU mortality (off-hours 2.7% vs weekdays 2.2%; P < .001). Multivariable regression revealed that, after adjustment for other significant factors, off-hours admission was associated with lower odds of mortality (odds ratio, 0.91; 95% confidence interval, 0.85-0.97; P = .004). Post hoc multivariable analysis revealed that admission during the morning period 6:00 am to 10:59 am was independently associated with death (odds ratio, 1.27; 95% confidence interval, 1.16-1.39; P < .0001).
  
  
  CONCLUSIONS
  Off-hours admission does not independently increase odds of death in the PICU. Admission from 6:00 am to 10:59 am is associated with increased risk for death and warrants further investigation in the PICU population.
authors.affiliation: Departments of Anesthesiology, Section on Pediatric Critical Care Medicine, mmccrory@wakehealth.edu.
authors.forename: Michael C
authors.initials: MC
authors.lastname: McCrory
authors.affiliation: Epidemiology, Ophthalmology.
authors.forename: Emily W
authors.initials: EW
authors.lastname: Gower
authors.affiliation: Division of Public Health Sciences, Department of Biostatistical Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina.
authors.forename: Sean L
authors.initials: SL
authors.lastname: Simpson
authors.affiliation: Departments of Anesthesiology, Section on Pediatric Critical Care Medicine.
authors.forename: Thomas A
authors.initials: TA
authors.lastname: Nakagawa
authors.affiliation: Departments of Anesthesiology, Section on Pediatric Critical Care Medicine.
authors.forename: Steven S
authors.initials: SS
authors.lastname: Mou
authors.affiliation: Internal Medicine, Section on Pulmonary and Critical Care Medicine, and.
authors.forename: Peter E
authors.initials: PE
authors.lastname: Morris
mesh_terms: D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D016638:Critical Illness / Q000401:mortality* / Q000628:therapy*; D016208:Databases, Factual / Q000639:trends; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D015278:Intensive Care Units, Pediatric / Q000592:standards* / Q000639:trends; D008297:Male; D010343:Patient Admission / Q000592:standards* / Q000639:trends; D012189:Retrospective Studies; D013997:Time Factors; D061665:Time-to-Treatment / Q000592:standards* / Q000639:trends
keywords: mortality; patient outcomes; pediatric critical care; time factors