Greg Hare MD, PhD
Cardiovascular and Respiratory Platform
Contact Info
T: (416) 864-5259
F: (416) 864-6014
Clinical Interests
His clinical focus is to develop multimodal and inter-professional approaches to optimize patient outcomes through patient blood management strategies.
Research Interests
Cerebral tissue; oxygen delivery

Professor, Departments of Anesthesia and Physiology
Co-Director of the St. Michael’s Center of Excellence in Patient Blood Management
Department of Anesthesia, St. Michael’s Hositpal, University of Toronto


Research Synopsis

Dr. Hare is a Staff Anesthesiologist, Professor of Anesthesia and Physiology,  at St. Michael’s Hospital at the University of Toronto. His clinical focus is to develop multimodal and inter-professional approaches to optimize patient outcomes through patient blood management strategies. His long term research goal is to define mechanisms of anemia-induced morbidity and mortality; and to design novel treatment strategies to prevent these adverse outcomes. His research is focused on defining adaptive, and maladaptive, cardiovascular mechanisms in experimental models of acute hemodilution using integrative whole animal models. These translational studies have defined mechanism of anemia-induced tissue hypoxia and mortality. Dr. Hare’s laboratory has also identified adaptive mechanism, including neuronal nitric oxide synthase-derived nitric oxide, which promote organism survival during acute anemia. In addition, their laboratory has demonstrated that acute beta-blockade interferes with adaptive cardiovascular mechanisms which sustain cerebral oxygen delivery during anemia-possibly explaining the negative interaction between acute anemia and beta-blockade and the increased incidence of stroke in beta-blockaded patients. The laboratory is currently focused on translational approaches to identify patient specific biomarkers of anemia-induced tissue hypoxia in order to identify when patients are at risk of anemia induced morbidity and mortality; and to derive patient specific therapies which  can reduce morbidity and mortality associated with both anemia and red blood cell transfusion. The overall clinical goal is to reduce morbidity and mortality associated with anemia in peri-operative patients.

Current research utilizes both physiological and molecular models to define mechanisms of anemia induced cerebral injury. He has recently demonstrated increased expression of vascular endothelial growth factor and neuronal nitric oxide synthase in the cerebral cortex of anemic animal, suggesting that cerebral hypoxia may contribute to neurological injury in anemic animals at clinically relevant hemoglobin concentrations. Additional studies are directed toward assessing the impact of acute anemia on neurological outcomes in experimental models of traumatic brain injury and cardiopulmonary bypass.

As the Chairman of the blood conservation committee at St. Michael’s Hospital, Greg is able to apply knowledge gained in the basic science laboratory toward optimizing management of patients suffering from acute blood loss. His research also has direct impact on the management of patients undergoing cardiopulmonary bypass.

Publications and Awards

View PubMed search of this faculty member's recent publications.

Recent Publications

J Neurosurg Anesthesiol. 2015 Jul;27(3):270-1. doi: 10.1097/ANA.0000000000000137
Selective Right Lower Lobe Isolation to Control CO2 in a Patient With Raised ICP Undergoing Craniotomy.