title: Time trends in organ donation after neurologic determination of death: a cohort study.
abstract: BACKGROUND
  The cause of brain injury may influence the number of organs that can be procured and transplanted with donation following neurologic determination of death. We investigated whether the distribution of causes responsible for neurologic death has changed over time and, if so, whether this has had an impact on organ quality, transplantation rates and recipient outcomes.
  
  
  METHODS
  We performed a cohort study involving consecutive brain-dead organ donors in southern Alberta between 2003 and 2014. For each donor, we determined last available measures of organ injury and number of organs transplanted, and compared these variables for various causes of neurologic death. We compared trends to national Canadian data for 2000-2013 (2000-2011 for Quebec).
  
  
  RESULTS
  There were 226 brain-dead organ donors over the study period, of whom 100 (44.2%) had anoxic brain injury, 63 (27.9%) had stroke, and 51 (22.6%) had traumatic brain injury. The relative proportion of donors with traumatic brain injury decreased over time (> 30% in 2003-2005 v. 6%-23% in 2012-2014) (p= 0.004), whereas that with anoxic brain injury increased (14%-37% v. 46%-80%, respectively) (p< 0.001). Nationally, the annual number of brain-dead donors with traumatic brain injury decreased from 4.4 to less than 3 per million population between 2000 and 2013, and that with anoxic brain injury increased from 1.1 to 3.1 per million. Donors with anoxic brain injury had higher concentrations of creatinine, alanine aminotransferase and troponin T, and lower PaO2/FIO2 and urine output than donors with other diagnoses. The average number of organs transplanted per donor was 3.6 with anoxic brain injury versus 4.5 with traumatic brain injury or stroke (p= 0.002).
  
  
  CONCLUSIONS
  Anoxic brain injury has become a leading cause of organ donation after neurologic determination of death in Canada. Organs from donors with anoxic brain injury have a greater degree of injury, and fewer are transplanted. These findings have implications for availability of organs for transplantation in patients with end-stage organ failure.
authors.affiliation: Departments of Critical Care Medicine (Kramer, Doig) and Clinical Neurosciences (Kramer), University of Calgary; Southern Alberta Organ and Tissue Donation Program (Kramer, Baht); Department of Community Health Sciences (Doig), University of Calgary, Calgary, Alta.
authors.forename: Andreas H
authors.initials: AH
authors.lastname: Kramer
authors.affiliation: Departments of Critical Care Medicine (Kramer, Doig) and Clinical Neurosciences (Kramer), University of Calgary; Southern Alberta Organ and Tissue Donation Program (Kramer, Baht); Department of Community Health Sciences (Doig), University of Calgary, Calgary, Alta.
authors.forename: Ryan
authors.initials: R
authors.lastname: Baht
authors.affiliation: Departments of Critical Care Medicine (Kramer, Doig) and Clinical Neurosciences (Kramer), University of Calgary; Southern Alberta Organ and Tissue Donation Program (Kramer, Baht); Department of Community Health Sciences (Doig), University of Calgary, Calgary, Alta.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Doig