50 patients aged more than 60 years old undergoing elective abdominal surgery expected
to last more than 2 hours were randomized into 2 groups of 25 patients each: those receiving Dexmedetomidine
at a dose of 0.4 lg/kg/h, group (A) and those receiving 0.9% normal saline as placebo
group (B). All patients underwent neuropsychometric tests (Montreal cognitive assessment
and Stroop color word interference tests) the day before the surgery and 24 h after the surgery,
and one week postoperatively.