Perioperative Cognitive Function - Dexmedetomidine and Cognitive Reserve
Condition: Postoperative Delirium; PD; Postoperative Cognitive Dysfunction; POCD
MeSH terms: Delirium; Emergence Delirium; Postoperative Cognitive Complications; Cognitive Dysfunction
Intervention: Precedex (Dexmedetomidine); Placebo
Intervention description: 0.5/ug/kg/hr Dexmedetomidine infusions will begin prior to the surgery (no loading dose), and will be maintained at 0.5 mcg/kg/hour throughout surgery and titrated postoperatively for 2 hours postoperatively.; 0.5/ug/kg/hr Placebo infusions will begin prior to the surgery (no loading dose), and will be maintained at 0.5 mcg/kg/hour throughout surgery and titrated postoperatively for 2 hours postoperatively.
Intervention MeSH terms: Dexmedetomidine
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 404.0
Sex: All
Minimum age: 68 Years
Healthy volunteers: No
Keywords: Postoperative Confusion; Postoperative Delirium; PD; Postoperative Cognitive Dysfunction; POCD

Summary:

      Elderly patients who undergo anesthesia and non-cardiac surgery are subject to deterioration
      of brain function including the development of postoperative delirium (PD) and postoperative
      cognitive dysfunction (POCD). These disorders cause disability, distress for both patients
      and their families, are associated with other medical complications and account for
      significant additional health care costs. We currently use relatively primitive approaches to
      preventing and treating PD and POCD.

      Dexmedetomidine is a drug used for sedation in critically ill patients that provides some
      pain relief and controls the bodies response to stress. The sedation produced by
      dexmedetomidine appears more similar to natural sleep than any other drug used for anesthesia
      and postoperative sedation. Data suggesting that dexmedetomidine can prevent delirium
      following cardiac surgery and the developing understanding of the causes of PD and POCD
      suggest that dexmedetomidine will be particularly effective.
    

Eligibility criteria:

        Inclusion Criteria:

          -  68 and older

          -  elective major surgery under general anesthesia(major surgery is defined by a planned
             2 day hospitalization)

          -  ASA physical status I-III

          -  capable and willing to consent

          -  MMSE > 20 (to exclude dementia)

        Exclusion Criteria:

          -  Cardiac surgery

          -  Intracranial Surgery

          -  Emergency Surgery

          -  Patients with severe visual or auditory disorder/handicaps

          -  Illiteracy

          -  Patients with clinically significant Parkinson's Disease

          -  Patients not expected to be able to complete the 3 and 6 month postoperative tests

          -  Sick sinus syndrome without pacemaker

          -  Hypersensitivity to drug or class

          -  Current 2nd or 3rd degree AV block

          -  History of clinically significant bradycardia

          -  Contraindication to the use of an 2A-agonist

          -  Presence of a major psychiatric condition such as bipolar disorder, major depression,
             schizophrenia, or dementia

          -  ASA physical status IV or V