title: Time to Death after Terminal Withdrawal of Mechanical Ventilation: Specific Respiratory and Physiologic Parameters May Inform Physician Predictions.
abstract: BACKGROUND
  Discussions about withdrawal of life-sustaining therapies often include family members of critically ill patients. These conversations should address essential components of the dying process, including expected time to death after withdrawal.
  
  
  OBJECTIVE
  The study objective was to aid physician communication about the dying process by identifying predictors of time to death after terminal withdrawal of mechanical ventilation.
  
  
  METHODS
  We conducted an observational analysis from a single-center, before-after evaluation of an intervention to improve palliative care. We studied 330 patients who died after terminal withdrawal of mechanical ventilation. Predictors included patient demographics, laboratory, respiratory, and physiologic variables, and medication use.
  
  
  RESULTS
  The median time to death for the entire cohort was 0.58 hours (interquartile range (IQR) 0.22-2.25 hours) after withdrawal of mechanical ventilation. Using Cox regression, independent predictors of shorter time to death included higher positive end-expiratory pressure (per 1 cm H2O hazard ratio [HR], 1.07; 95% CI 1.04-1.11); higher static pressure (per 1 cm H2O HR, 1.03; 95% CI 1.01-1.04); extubation prior to death (HR, 1.41; 95% CI 1.06-1.86); and presence of diabetes (HR, 1.75; 95% CI 1.25-2.44). Higher noninvasive mean arterial pressure predicted longer time to death (per 1 mmHg HR, 0.98; 95% CI 0.97-0.99).
  
  
  CONCLUSIONS
  Comorbid illness and key respiratory and physiologic parameters may inform physician predictions of time to death after withdrawal of mechanical ventilation. An understanding of the predictors of time to death may facilitate discussions with family members of dying patients and improve communication about end-of-life care.
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington , Seattle, Washington.
authors.forename: Ann C
authors.initials: AC
authors.lastname: Long
authors.affiliation: 2 EvergreenHealth Pulmonary Care , Kirkland, Washington.
authors.forename: Sarah
authors.initials: S
authors.lastname: Muni
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington , Seattle, Washington.
authors.forename: Patsy D
authors.initials: PD
authors.lastname: Treece
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington , Seattle, Washington.
authors.forename: Ruth A
authors.initials: RA
authors.lastname: Engelberg
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington , Seattle, Washington.
authors.forename: Elizabeth L
authors.initials: EL
authors.lastname: Nielsen
authors.affiliation: 3 Department of Family Medicine, University of Washington , Seattle, Washington.|4 Department of Epidemiology, University of Washington , Seattle, Washington.
authors.forename: Annette L
authors.initials: AL
authors.lastname: Fitzpatrick
authors.affiliation: 1 Department of Medicine, Division of Pulmonary and Critical Care Medicine, Harborview Medical Center, University of Washington , Seattle, Washington.
authors.forename: J Randall
authors.initials: JR
authors.lastname: Curtis
mesh_terms: D017677:Age Distribution; D000368:Aged; D000369:Aged, 80 and over; D015897:Comorbidity; D003643:Death; D005260:Female; D006801:Humans; D007362:Intensive Care Units / Q000706:statistics & numerical data; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D012121:Respiration, Artificial; D012189:Retrospective Studies; D013727:Terminal Care; D013997:Time Factors; D028761:Withholding Treatment