A 10-year retrospective analysis on the incidence of anesthesia awareness with recall in adult patients under total intravenous anesthesia

Background: Intraoperative awareness occurrence ranges between 0.005% and 1.12% of general anesthesia cases and could be a devastating experience for a patient. The incidence of intraoperative awareness in total intravenous anesthesia (TIVA) is higher than in volatile anesthesia without the depth of anesthesia (DOA) monitoring. This retrospective study aimed to evaluate the incidence of intraoperative awareness with recall during TIVA in the isolated health facility. Methods: We performed a retrospective analysis of the incidence of intraoperative awareness with recall during TIVA that involved a large number of patients over 10 years (from January 2008 to July 2018). Cases of death, coma, dementia, severe psychological disorder, incomplete data, or patients aged under 20 years were excluded from this study. All data from the operating rooms' database and the anesthesia records were analyzed. Intraoperative awareness was detected by the patients who spontaneously self-reported accidental awareness during postoperative anesthetic visits within 2 days following the surgery. Moreover, we also visited highly suspected intraoperative awareness patients on a postoperative day 1 for clarifying intraoperative awareness with recall. Results: Of 13,002 patients under TIVA, 11,433 were included in this study. Two confirmed cases of intraoperative awareness were detected, with an incidence of 0.017% (2 of 11,433). As of the type of surgery, a 67-year-old male received elective general surgery and another 45-year-old male received elective orthopedic surgery. Only one patient was under DOA monitoring, and in both instances, no long-term psychological sequelae were reported. Conclusions: This study suggests that the incidence of intraoperative awareness during TIVA is a very rare event if the well-trained anesthesia staff for TIVA is present and when the DOA monitoring is routinely used in high-risk patients. Furthermore, based on the study data, we conclude that the two intraoperative awareness cases could have been prevented.