Effets des médicaments ayant un effet vasopresseur sur la fonction cérébrovasculaire des patients diabétiques de type 2

Chercheurs boursiers - Junior 1 | Concours 2012-2013


Patrice Brassard

Université Laval

 

Domaine : Santé circulatoire et respiratoire

A decrease in cerebral oxygenation during cardiac bypass surgery is associated with the presence of postoperative neurological problems, which are more common in patients with type 2 diabetes compared with patients without diabetes. However, the mechanisms underlying this decrease in cerebral oxygenation are poorly understood. When the perfusion pressure of vital organs such as the brain is challenged in response to induced hypotension, the use of vasopressor agents is an effective way to restore blood pressure and perfusion pressure in the brain. These vasopressors are administered in order to raise and/or maintain cerebral oxygenation to an acceptable level. However, we observed that the administration of vasopressors was associated with a decrease in cerebral oxygenation in healthy subjects and normotensive patients undergoing elective surgery. Among patients in whom surgery is planned under anesthesia, a history of diabetes is associated with a higher risk of developing hypotension requiring drug intervention. Thus, patients with type 2 diabetes are more likely to receive vasopressors, but the impact of this medication on cerebral oxygenation in these patients is unknown. The objective of this research program is to document whether the use of vasopressors is associated with a larger decline in cerebral oxygenation in patients with type 2 diabetes compared with control subjects, and to understand the underlying mechanisms of these changes in cerebral oxygenation. This research program is part of an overall research theme related to vascular physiology of patients with type 2 diabetes without cardiovascular complication in response to different pharmacological treatments.