The Impact of Ketamine on Postoperative Cognitive Dysfunction, Delirium, and Renal Dysfunction

The Impact of Ketamine on Postoperative Cognitive Dysfunction, Delirium, and Renal Dysfunction in Patients 75 Years of Age or Older and Undergoing Cardiac Surgery

Ketamine is a commonly used anesthetic medication which is used for induction of anesthesia as well as as an analgesic. It has been shown to have anti-inflammatory properties which may decrease post-operative complications following cardiac surgery with cardiopulmonary bypass that are thought to associated with inflammation. Some studies have shown that ketamine does decrease these complications when compared with anesthetics that are not commonly used in our cardiac anesthesiology practice. Propofol is another commonly used anesthetic medication which is used for induction of anesthesia. Ketamine has not been compared with propofol for potential to reduce post-operative complications associated with the inflammatory process. This study aims to see if ketamine will reduce the incidence of cognitive dysfunction, delirium, and renal dysfunction in comparison with propofol. In addition, the hemodynamic impact of ketamine compared propofol will be investigated.

Scheduled to undergo cardiac surgery.

Inclusion criteria:

• age greater than or equal to 75 years presenting for cardiac surgery at the Mayo Clinic in Rochester, Minnesota;
• schedule to undergo complex cardiac surgery. Complex cardiac surgery will be defined as surgery involving more than one heart valve, redo-sternotomy procedures, or combined valvular and CABG procedures.

Exclusion criteria will include:

• left or right ventricular assist device implantation or explantation,
• procedures not requiring cardiopulmonary bypass,
• active infection or sepsis, severe hepatic disease or ascites,
• pre-operative renal dysfunction including a baseline creatinine equal to or greater than 1.5 mg/dL or requiring dialysis,
• immunosuppressive medication use (including steroid use),
• immunodeficiency syndrome,
• known neurologic or psychiatric disorder, or
• use of drugs for psychosis.