The profound physiological disturbances associated with severe intracerebral pathology have long been recognized. These changes have also been described in the brain dead potential organ donor but have only been studied since the early 1980s. Physiological disturbances in the brain dead organ donor result in a diffuse vascular regulatory injury and a diffuse metabolic cellular injury. The net result of these changes is an inexorable deterioration of all organs and eventual "cardiovascular death" of the patient. This paper reviews these physiological changes and the effect they may have on solid transplantable tissues, and discusses the management of brain dead organ donor with regard to these changes. Current concepts of brain death and how they may affect the interpretation of the observed physiological changes are also reviewed.