The Physiology of Circulatory Arrest in Humans

The purpose of this study is to better understand what happens in the brain during the dying process. This is a prospective observational study conducted at the end of life in the ICU at VGH. At the time of withdrawal of life sustaining therapies the investigators will monitor brain blood flow and oxygenation. The investigators will also collect blood samples to measure biomarkers of brain dysfunction. This may help us to determine when blood flow to the brain stops and when brain function ceases. This information may provide researchers and the medical community as a whole with important information as to the best timing for organ donation. This study is the first step in commencing a research program related to improving the organ donation process. Our goal is to determine how best to provide high quality organs to those who would otherwise die without an organ transplant.