Cognitive decline is a common complication after cardiac surgery with cardiopulmonary bypass（CPB）,but as such no pharmacological therapy has been shown to be efficacious in preventing the decline.However,gastrodin has been shown to have multi-pharmacological effects on neurological functions.We undertook this study to test the hypothesis that gastrodin would potentially prevent CPB-associated neurocognitive decline.We randomly assigned 200 patients undergoing mitral valve replacement surgery to receive either gastrodin（40 mg/kg） or saline after the induction of anesthesia and subsequently evaluated cognitive function before surgery,at discharge,and at 3rd month after surgery by using a battery of five neurocognitive tests,or adverse effects of gastrodin postoperatively.Neurocognitive decline in postoperative function was defined as a drop of 1 SD or more in the scores on tests of any one of the four domains of cognitive function.Cognitive decline occurred in 9% of the patients in the gastrodin group in contrast to 42% in the control group（P〈0.01） at discharge.Cognitive outcome could be determined at 3rd month in 87 patients in the gastrodin group and 89 in the control group.Cognitive decline was detected in 6% in the gastrodin group and 31% in the control group（P〈0.01）.The incidences of possible adverse effects were similar between two groups.These results indicate that gastrodin is an effective and a safe drug for the prevention of neurocognitive decline in patients undergoing mitral valve replacement surgery with CPB.
