The Assessment of Explicit Memory and Implicit Memory after General Anesthesia for Cesarean Section Using the Process Dissociation Procedure / 대한마취과학회지

ABSTRACT

BACKGROUND: It is still unclear whether intraoperative events result entirely from moments of inadequate anesthesia. We used the process dissociation procedure to estimate implicit and explicit memory for words presented during elective cesarean sections. METHODS: Sixty patients undergoing elective cesarean sections were studied. We used a word stem completion test for memory testing. Four lists of words was played via headphones during cesarean section. During testing, two lists were used in the inclusion part (one target and one distractor list); the remaining two lists were used in the exclusion part. BIS was recorded on a computer during word presentation. RESULTS: The duration of surgery was 67.1+/-13.9 min. The mean BIS during word presentation was 73.4+/-2.5. In the inclusion part, target hit rates (i.e., the probability of responding sucessfully to a word presented during surgery) were statistically significantly higher than distractor hit rates (0.21 vs. 0.12), and in the exclusion part target hit rates were statistically significantly higher than distractor hit rates (0.17 vs. 0.11). During testing, none of the patients was able to recall the correct words presented during surgery when presented with the word stem aurally and visually. CONCLUSIONS: We found evidence of implicit memory after general anesthesia for cesarean section using the process dissociation procedure, and found that implicit memory can occur in the absence of conscious recall.