Isolated Brainstem Death is Rare and is Associated with Infratentorial Stroke Among Patients Suspected of Death by Neurologic Criteria
Joel Neves Briard1, Dean Fergusson2, Shane English3, Sonny Dhanani4, Alexis Turgeon5, Francois Lauzier6, Ian Ball7, Jai Jai Shankar8, Michael Chasse1
1Université de Montréal, 2Ottawa Hospital, 3The Ottawa Hospital, 4CHEO, 5CHU de Québec, 6CHU de Quebec-Universite Laval, 7Western University, 8University of Manitoba
Objective:
Our objective was to investigate the association between infratentorial stroke and isolated brainstem death (IBD) among patients suspected of neurologic death.
Background:
IBD occurs in patients who have a clinical examination consistent with death by neurologic criteria (DNC), but in whom there is ancillary test evidence of preserved supratentorial perfusion and absent infratentorial perfusion. There are currently no documented risk factors for IBD.
Design/Methods:
This was an analysis of the INDex trial, a 15-site prospective diagnostic accuracy study that enrolled adult patients admitted to the intensive care unit after a severe brain injury who were deeply comatose despite the absence of sedation. We identified patients with infratentorial ischemic or hemorrhagic stroke using non-contrast CT scans. Patients underwent consecutive clinical examination for DNC and a brain CT-perfusion scan. IBD was diagnosed in patients with (1) a clinical examination consistent with DNC, and (2) preserved supratentorial perfusion despite absent infratentorial perfusion on the CT-perfusion scan. We estimated the association between infratentorial stroke and IBD using a generalized linear mixed model with a logit link function and intercept random effects for participating site, while adjusting for relevant pre-specified covariables using inverse probability weighting based on a propensity score. We also calculated the predictive values of infratentorial stroke for IBD.
Results:
Among 274 included patients, the median [IQR] age was 60.0 [47.0-69.0] years, 130 (47%) were female, and 30 (11%) had an infratentorial stroke. The prevalence of IBD was 1.8% (95% CI: 0.6-4.2%). Infratentorial stroke was associated with IBD (aOR: 16.81, 95% CI: 3.95-71.51). The positive predictive value of infratentorial stroke for IBD was 10.0% (95% CI: 3.5-25.6%), whereas its negative predictive value was 99.2% (95% CI: 97.1-99.8%).
Conclusions:
Infratentorial stroke is associated with IBD among patients suspected of DNC. In the absence of infratentorial stroke, the probability of IBD in this population is very low.