Intraoperative Awareness: Comparison Between Total Intravenous Anesthesia (TIVA) and Balanced Anesthesia: A Prospective Observational Study

Abstract

Introduction. Intraoperative awareness is a rare but clinically significant complication of general anesthesia characterized by the recovery of consciousness, with or without explicit recall, during surgery. Although its incidence is generally low, awareness may result in relevant psychological consequences, including anxiety, intrusive memories, sleep disturbances, and post-traumatic stress disorder. The risk may vary according to anesthetic technique and the adequacy of anesthetic depth monitoring. This study aimed to assess the occurrence of intraoperative awareness among patients undergoing general anesthesia and to describe its occurrence according to the use of total intravenous anesthesia (TIVA) or balanced anesthesia.

Methods. A prospective observational study was conducted among 100 adult patients undergoing endocrine surgery under general anesthesia. Data were collected at two time points. During the intraoperative phase (T0), clinical characteristics, anesthetic technique, monitoring modalities, and signs potentially suggestive of awareness were recorded. One hour after emergence from anesthesia (T1), patients completed the Modified Brice Questionnaire to identify memories, dreams, or perceptions related to the intraoperative period.

Results. Of the 100 patients included, 76 underwent TIVA and 24 received balanced anesthesia. One case of intraoperative awareness was identified, corresponding to an overall incidence of 1%. The episode occurred during TIVA and was associated with intraoperative involuntary movements and increased heart rate. Postoperative assessment confirmed recollection compatible with awareness. Most participants reported no intraoperative memories or unusual perceptions.

Discussion. Intraoperative awareness was uncommon in this sample but occurred during TIVA. These findings support careful assessment of anesthetic depth and the use of appropriate monitoring strategies, particularly during total intravenous anesthesia. Standardized protocols and continuous clinical surveillance remain important components of perioperative patient safety.