Comparison of occurrence of postoperative cognitive dysfunction in elderly patients using different anesthetic methods / 中华麻醉学杂志

ABSTRACT

Objective To compare the occurrence of postoperative cognitive dysfunction (POCD) in elderly patients using differentanesthetic methods.Methods Ninety-three ASA Ⅱ or Ⅲ patients,aged ≥ 65 yr,weighing 45-67 kg,scheduled for artificial femoral head replacement,were randomly divided into 2 groupsgeneral anesthesia (group G,n =47) and combined spinal-epidural anesthesia group (group S-E,n =46).In group G,anesthesia was induced with iv injection of midazolam 0.1 mg/kg,propofol 2 mg/kg,fentanyl 3-5μg/kg,and vecuronium 0.1 mg/kg,and maintained with continuous infusion of propofol 2-3 mg· kg-1 · h-1,intermittent iv boluses of fentanyl 1 μg/kg and vecuronium 0.04 mg/kg and inhalation of 1.5％-2.0％ isoflurane.In group S-E,hyperbaric 0.5 ％ ropivacaine 2 ml was injected into the subarachnoid space over 20 s,the patients were kept in the original position for 15 min,the level of anesthesia was simultaneously adjusted to below T8 on the operated side,and 0.5 ％ ropivacaine 3-5 ml was injected into the epidural space when needed during operation.Cognitive function was assessed by mini-mental state examination at 24 h before anesthesia and 24 and 72 h after operation.Venous blood samples were collected for determination of plasma amyloid-beta levels by ELISA.Results Compared with group G,the incidence of POCD at 24 h after operation and level of plasma amyloid-beta were significantly decreased in group S-E (P ＜ 0.05).Conclusion Elderly patients are more likely to develop POCD under general anesthesia than under combined spinal-epidural anesthesia.