Mental state change after general and regional anesthesia in adults and elderly patients, a randomized clinical trial.

ABSTRACT

BACKGROUND: Mental state changes after anesthesia seemed to be more frequent in older patients, but the results were still unclear. OBJECTIVE: To compare the mental scores between adults and elderly patients after general and regional anesthesia. METHODS: This was a stratified randomized trial with factorial design. Sixty patients > or = 60 years old and sixty patients < 60 years old were randomly assigned to receive general or regional anesthesia. Their mental states were assessed blind by investigators, using the Thai Mental State Examination score. RESULTS: The two anesthetic groups showed no difference in the mental scores, but the two age groups showed significantly different scores. The components of mental states that were significantly different were orientation and recall. There were no significant differences in registration, attention, calculation and language. The model for predicting the score included age, education level and narcotics given within six hours before assessment. Sex, weight, intraoperative hypotension, blood loss and duration of anesthesia could not explain the change in the scores. CONCLUSION: Age, but not anesthetic technique, affected the mental scores after anesthesia.