CT-Perfusion for Neurological Diagnostic Evaluation

For the purpose of organ donation after neurological determination of death (NDD), death must be declared using a set of standardized clinical criteria. When a full clinical evaluation cannot be completed, additional neuroimaging ancillary testing is required. The ideal ancillary test for NDD would demonstrate no cerebral blood flow, be free of false-positive and false negative results, rapid, safe, readily available, non-invasive, and inexpensive. No current ancillary test for NDD meets these criteria. Computed tomography (CT) perfusion has the characteristics of an ideal test for NDD, but has not been evaluated for routine clinical use for NDD. The overarching goal of this project is to improve the NDD process by establishing CT-perfusion as the ideal ancillary test. A large prospective Canadian multi-centre diagnostic cohort study will be conducted to validate CT-perfusion for the neurological determination of death. Specific objectives are: Primary objective: To determine diagnostic accuracy of CT-perfusion compared to complete clinical evaluation for NDD. Secondary objectives: 1) To confirm the safety of performing CT-perfusion in critically ill patients suspected of being neurologically deceased; 2) To establish the CT-perfusion inter-rater reliability for NDD; 3) To evaluate the diagnostic accuracy of CT-angiography compared to complete clinical evaluation and to CT-perfusion for NDD; 4) To describe the clearance of commonly used sedatives and narcotics in the setting of NDD; and 5) to investigate biological changes (inflammatory and nanovesicles) that occur in humans during the brain dying process.