Decline in cognitive function after surgery occurs most commonly in older patients and patients undergoing major surgeries, such as heart surgery. Postoperative Cognitive Dysfunction (POCD) may last a prolonged period of time while Postoperative Delirium (POD) is a more acute disturbance in attention, awareness and cognition. The cause of POCD and POD are not fully understood, however some of the pathophysiology of POCD is similar to that of Alzheimer's disease (AD).

Insulin given intravenously during heart surgery has been shown to preserve short and long-term memory function after the operation. Clinical trials further demonstrated that insulin given via the nose (intranasal) improves memory performance of patients with AD or cognitive impairment suggests that intranasal insulin also could be a therapeutic option for POCD and POD.

This study is designed to examine the effect intranasal insulin on POCD and POD. The goal is to investigate whether administration of intranasal insulin during and after heart surgery improves cognitive function postoperatively.

Inclusion Criteria:

•elective open heart surgery requiring cardiopulmonary bypass

Exclusion Criteria:

• inability to provide informed consent
• allergy to insulin
• pregnancy
• mother tongue other than English or French
• visual or hearing impairment interfering with the ability to complete cognitive tests.