[Word recognition test after general anesthesia: the influence of previous anesthesia]

Among other higher brain functions such as consciousness and learning, general anesthesia also affects memory. A number of information retrieval tests are performed to determine the effects of drugs on explicit memory. In this study, we investigated the recognition of words before and after general anesthesia in subjects having and not having received anesthesia on one or more occasions before the present one. The study included 51 patients, ASA physical status I or II, median age 50, at least high-school graduates, without head trauma, known psychiatric or memory disorder, and taking no psychoactive medication. A standardized anesthesia technique, a single surgical procedure and a defined study-test interval were used. We designed our own test as a combination of story recall test and brief word learning test, both widely used in psychological and psychiatric examination. There was no significant difference in word recognition before and after general anesthesia in either patient group. Many studies indicate that anesthesia and surgery are associated with cognitive impairment lasting for 33 months in 10%-14% of elderly patients. We hypothesized that general anesthetics can cause prolonged cognitive alterations. Study results showed that previous anesthesia in addition to the current one had no significant influence on the word recognition test.