POSTOPERATIVE ANTEROGRADE AMNESIA

The problems of defining and estimating pre- and postoperative amnesia are discussed. The extent of postoperative (anterograde) amnesia in patients receiving pre-operative medication (consisting of atropine, pethidine and pentobarbitone) followed by general anaesthesia (consisting of thiopentone, halothane and nitrous oxide) was ascertained. Two control groups were employed; one received spinal anaesthesia following pre-operative medication, and the other received no medication and did not undergo surgery. Various age groups were compared and various memory tests were employed. Results indicate that postoperative amnesia is primarily related to the general anaesthetic and not to the pre-operative medication. In some studies designed to elucidate the extent of pre- and postoperative amnesia, the role that pre-operative medications play in producing the amnesia is referred to. For instance, Feldman (1963) asked patients if they remembered the in-jection before they went to sleep. An appreciable