Relationship between postoperative cognitive dysfunction after major non-cardiac surgery and intraoperative cerebral oxygen metabolism in elder patients / 中华麻醉学杂志

ABSTRACT

Objective To investigate the changes of cognitive function after major non-cardiac surgery and the relationship between the postoperative cognitive dysfunction(POCD)and the intraoperative cerebral oxygen metabolism in the elderly.Methods Sixty-four patients(49 male,12 female)aged 65-85 yr undergoing elective major non-cardiac surgery were enrolled in this study.A battery of four neuropsycbological tests was administered 2-3 days before and 7 days after surgery by an experienced psychometrician.A postoperative deficit in any test was defined as a cognitive decline by more than or equal to the preoperative standard deviation of that test in all patients.As long aft any patient showed cognitive decline in two or more tests.this situation was defined as POCD.Blood samples were taken from radial artery and internal jugIIlar vein simultaneously for blood gas analysis immediately (T1) and 2 h (T2) after induction of anesthesia,and just before leaving postanesthesia care unit (T3).The ratio of cerebral blood flow to cerebral oxygen metabolic rate(CBF.CMR02)was calculated.Results Sixty-one patients completed postoperative neuropsychological tests and 10 cases(16.4%)had POCD.Logistic regression analysis showed that the abnormality of CBF/CMR02 during operation was associated with the occurrence of POCD.Conclusion The occurrence of POCD after major non-cardiac surgery is related to the abnormality of cerebral oxygen metabolism during operation.