title: Cognitive and functional competence after anaesthesia in patients aged over 60: controlled trial of general and regional anaesthesia for elective hip or knee replacement.
abstract: OBJECTIVE
  To determine the influence of general or regional anaesthesia on long term mental function in elderly patients.
  
  
  METHODS
  Prospective study of patients randomly allocated to receive general or regional anaesthesia.
  
  
  METHODS
  The patients' homes and a large teaching hospital in Cardiff.
  
  
  METHODS
  146 Patients aged 60 and over scheduled for elective hip or knee replacement.
  
  
  METHODS
  Scores achieved in tests of cognitive function and functional competence.
  
  
  RESULTS
  72 Patients were allocated to receive general anaesthesia and 74 regional anaesthesia. Anaesthetic technique did not influence the duration of the operation, time to mobilisation postoperatively, requirements for analgesia after the operation, or duration of stay in hospital. Three months after the operation there was an improvement in the score for the recognition component (76 ms, 95% confidence interval 9 to 144) and the response component (82 ms, 5 to 158) of the choice reaction time in the group receiving general anaesthesia compared with the group receiving regional anaesthesia. This was the only significant difference between the two groups in the assessments of cognitive and functional competence. Eleven patients receiving regional anaesthesia and 12 receiving general anaesthesia reported that their memory and concentration were worse than before the operation, but this was not confirmed by testing.
  
  
  CONCLUSIONS
  Cognitive and functional competence in elderly patients was not detectably impaired after either general or regional anaesthesia when attention was paid to the known perioperative influences on mental function.
authors.affiliation: University of Wales, College of Medicine, Cardiff.
authors.forename: M J
authors.initials: MJ
authors.lastname: Jones
authors.forename: S E
authors.initials: SE
authors.lastname: Piggott
authors.forename: R S
authors.initials: RS
authors.lastname: Vaughan
authors.forename: A J
authors.initials: AJ
authors.lastname: Bayer
authors.forename: R G
authors.initials: RG
authors.lastname: Newcombe
authors.forename: T C
authors.initials: TC
authors.lastname: Twining
authors.forename: J
authors.initials: J
authors.lastname: Pathy
authors.forename: M
authors.initials: M
authors.lastname: Rosen
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000765:Anesthesia, Conduction / Q000523:psychology*; D000768:Anesthesia, General / Q000523:psychology*; D003071:Cognition; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006760:Hospitalization; D006801:Humans; D007720:Knee Prosthesis; D008297:Male; D008606:Mental Processes; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D011897:Random Allocation