Perception and practices of depth of anesthesia monitoring and intraoperative awareness event rate among Jordanian anesthesiologists: a cross-sectional study.

BACKGROUND: Intraoperative awareness is the second most common complication of surgeries, and it negatively affects patients and healthcare professionals. Based on the limited previous studies, there is a wide variation in the incidence of intraoperative awareness and in the practices and attitudes toward depth of anesthesia (DoA) monitoring among healthcare systems and anesthesiologists. This study aimed to evaluate the Jordanian anesthesiologists' practice and attitudes toward DoA monitoring and estimate the event rate of intraoperative awareness among the participating anesthesiologists. METHODS: A descriptive cross-sectional survey of Jordanian anesthesiologists working in public, private, and university hospitals was utilized using a questionnaire developed based on previous studies. Practice and attitude in using DoA monitors were evaluated. Anesthesiologists were asked to best estimate the number of anesthesia procedures and frequency of intraoperative awareness events in the year before. Percentages and 95% Confidence Intervals (95%CI) were reported and compared between groups using chi-square tests. RESULTS: A total of 107 anesthesiologists responded and completed the survey. About one-third of the respondents (34.6%; 95% CI 26.1-44.2) had never used a DoA monitor and only 6.5% (95% CI 3.1-13.2) reported using it as a "daily practice". The use of a DoA monitor was associated with experience and type of health sector. However, 81.3% (95% CI 66.5-83.5) believed that currently available DoA monitors are effective for DoA monitoring and only 4.7% (95%CI 1.9-10.8) reported it as being "invalid". Most respondents reported that the main purpose of using a DoA monitor was to prevent awareness (86.0%; 95%CI 77.9-91.4), guide the delivery of anesthetics (63.6%; 95%CI 53.9-72.2), and reduce recovery time (57%; 95%CI 47.4-66.1). The event rate of intraoperative awareness was estimated at 0.4% among participating anesthesiologists. Most Jordanian hospitals lacked policy intending to prevent intraoperative awareness. CONCLUSIONS: Most anesthesiologists believed in the role of DoA monitors in preventing intraoperative awareness, however, their attitudes and knowledge are inadequate, and few use DoA monitors in routine practices. In Jordan, large efforts are needed to regulate the use of DoA monitoring and reduce the incidence of intraoperative awareness.

A survey of current practices, attitudes and demands of anaesthesiologists regarding the depth of anaesthesia monitoring in China.

BACKGROUND: In this study, we aimed to analyse survey data to explore two different hypotheses; and for this purpose, we distributed an online survey to Chinese anaesthesiologists. The hypothetical questions in this survey include: (1) Chinese anaesthesiologists mainly use the depth of anaesthesia (DoA) monitors to prevent intraoperative awareness and (2) the accuracy of these monitors is the most crucial performance factor during the clinical daily practice of Chinese anaesthesiologists. METHODS: We collected and statistically analysed the response of a total of 12,750 anesthesiologists who were invited to participate in an anonymous online survey. The Chinese Society of Anaesthesiologists (CSA) trial group provided the email address of each anaesthesiologist, and the selection of respondents was random from the computerized system. RESULTS: The overall response rate was 32.0% (4037 respondents). Only 9.1% (95% confidence interval, 8.2-10.0%) of the respondents routinely used DoA monitors. Academic respondents (91.5, 90.3-92.7%) most frequently used DoA monitoring to prevent awareness, whereas nonacademic respondents (88.8, 87.4-90.2%) most frequently used DoA monitoring to guide the delivery of anaesthetic agents. In total, the number of respondents who did not use a DoA monitor and whose patients experienced awareness (61.7, 57.8-65.6%) was significantly greater than those who used one or several DoA monitors (51.5, 49.8-53.2%). Overall, the crucial performance factor during DoA monitoring was considered by 61.9% (60.4-63.4%) of the respondents to be accuracy. However, most respondents (95.7, 95.1-96.3%) demanded improvements in the accuracy of the monitors for DoA monitoring. In addition, broad application in patients of all ages (86.3, 85.2-87.4%), analgesia monitoring (80.4, 79.2-81.6%), and all types of anaesthetic agents (75.6, 74.3-76.9%) was reported. In total, 65.0% (63.6-66.5%) of the respondents believed that DoA monitors should be combined with EEG and vital sign monitoring, and 53.7% (52.1-55.2%) believed that advanced DoA monitors should include artificial intelligence. CONCLUSIONS: Academic anaesthesiologists primarily use DoA monitoring to prevent awareness, whereas nonacademic anaesthesiologists use DoA monitoring to guide the delivery of anaesthetics. Anaesthesiologists demand high-accuracy DoA monitors incorporating EEG signals, multiple vital signs, and antinociceptive indicators. DoA monitors with artificial intelligence may represent a new direction for future research on DoA monitoring.

Raw and processed electroencephalography in modern anesthesia practice: a brief primer on select clinical applications.

The evidence supporting the intraoperative use of processed electroencephalography (pEEG) monitoring to guide anesthetic delivery is growing rapidly. This article reviews the key features of electroencephalography (EEG) waveforms and their clinical implications in select patient populations and anesthetic techniques. The first patient topic reviewed is the vulnerable brain. This term has emerged as a description of patients who may exhibit increased sensitivity to anesthetics and/or may develop adverse neurocognitive effects following anesthesia. pEEG monitoring of patients who are known to have or are suspected of having vulnerable brains, with focused attention on the suppression ratio, alpha band power, and pEEG indices, may prove useful. Second, pEEG monitoring along with vigilant attention to anesthetic delivery may minimize the risk of intraoperative awareness when administering a total intravenous anesthesia in combination with a neuromuscular blockade. Third, we suggest that processed EEG monitoring may play a role in anesthetic and resuscitative management when adverse changes in blood pressure occur. Fourth, pEEG monitoring can be used to better identify anesthesia requirements and guide anesthetic titration in patients with known or suspected substance use.

Craneotomía en el paciente despierto / Awake craniotomy

Introducción: La craneotomía con el paciente despierto es útil para lograr resecciones cerebrales amplias de lesiones de áreas elocuentes. Objetivo: Presentar un caso al que se le realizó la técnica dormido- despierto. Método: Se realizó la inducción de la anestesia con propofol/fentanilo/rocuronio y se colocó una mascarilla laríngea. Después del bloqueo de escalpe se mantuvo la infusión de propofol/fentanilo y lidocaína hasta que se realizó la craneotomía. Se disminuyó la velocidad de infusión y se mantuvo de esta manera hasta finalizada la intervención. Resultados: Se logró el despertar del paciente a los 13 minutos de reducida la infusión. Se mantuvo buena estabilidad hemodinámica, sin depresión respiratoria ni otras complicaciones. El paciente se mantuvo colaborador, respondió preguntas y movilizó sus extremidades. No presentó complicaciones posoperatorias. Discusión: Dentro de las técnicas anestésicas utilizadas en el mundo la dormido- despierto-dormido es la más popular; sin embargo, constituye una alternativa no dormir nuevamente al paciente ni reinstrumentar la vía respiratoria. Los medicamentos más empleados son el propofol/remifentanilo, aunque la comparación con otros opioides no arrojan diferencias significativas; aunque sí supone un beneficio adicional la dexmedetomidina. Conclusiones: La craneotomía con el paciente despierto es posible de realizar en el entorno hospitalario siempre que exista un equipo multidisciplinario que consensue las mejores acciones médicas para el paciente(AU)

Introduction: Awake craniotomy is useful to achieve wide brain resections of lesions in eloquent areas. Objective: To present the case of a patient who was operated on with the asleep-awake-asleep technique. Method: Anesthesia was induced with propofol-fentanyl-rocuronium and a laryngeal mask was placed. After scalp block, the propofol-fentanyl and lidocaine infusion was maintained until craniotomy was performed. The infusion rate was decreased and remained this way until the end of the intervention. Results: The patient was awakened thirteen minutes after the infusion was reduced. Good hemodynamic stability was maintained, without respiratory depression or other complications. The patient remained collaborative, answered questions, and mobilized his limbs. He had no postoperative complications. Discussion: Among the anesthetic techniques used in the world, asleep-awake-asleep is the most popular. However, it is an alternative not to put the patient back to sleep or re-instrument the airway. The most commonly used drugs are propofol-remifentanil, although the comparison with other opioids does not show significant differences, except for dexmedetomidine, which does represent an additional benefit. Conclusions: Awake craniotomy is possible to be performed in the hospital setting as long as there is a multidisciplinary team that agrees on the best medical actions for the patient(AU)

Unintended intraoperative awareness: An analysis of Perioperative Anesthetic Adverse Events in Thailand (PAAd Thai).

BACKGROUND: Despite the improvement of anesthetic-related modalities, the incidence of unintended intraoperative awareness remains at around 0.005-0.038%. OBJECTIVE: We aimed to describe the intraoperative awareness incidents that occurred across Thailand between January to December, 2015. METHODS: Observational data was collected from 22 hospitals throughout Thailand. The awareness category was selected from incident reports according to the Perioperative Anesthetic Adverse Events in Thailand (PAAd Thai) study database and descriptive statistics were analyzed. The awareness characteristics and the related factors were recorded. RESULTS: A total of nine intraoperative awareness episodes from 2000 incidents were observed. The intraoperative awareness results were as follows: experience of pain (38.1%), perception of sound (33.3%), perception of intubation (9.5%) and feeling of paralysis (14.3%). The observed factors that affect intraoperative awareness were anesthesia-related (100%), patient-related (55.5%), surgery-related (22.2%) and systematic process-related (22.2%). The contributing factors were situational inexperience (77.8%) and inappropriate patient evaluation (44.4%). An awareness of anesthetic performer (100%) and experience (88.9%) were defined as incident-mitigating factors. The suggested corrective strategies were quality assurance activity (88.9%), improved supervision (44.4%) and equipment utilization (33.3%), respectively. CONCLUSION: Nine intraoperative awareness incidents were observed, however the causes were preventable. The anesthetic component seems to be the most influential to prevent these events.

Accidental awareness while under general anaesthesia.

Accidental awareness during general anaesthesia may cause many intraoperative discomforts and bring further moderate to severe long-term symptoms including flashbacks, nightmares, hyperarousal or post-traumatic stress disorder. The incidence of awareness varied from 0.017% to 4% among studies. The relatively reliable incidence of intraoperative awareness with postoperative recall is 0.02%. The reason causing awareness was unclear. Insufficient anaesthetic dosing was thought as the principal cause. Even awareness was not comprehensively understood, some endeavors have been raised to prevent or reduce it, including i) Reducing the insufficient anaesthetic dosing induced by negligence; ii) Providing close clinical observation and clinical parameters from the monitor such as bispectral index or electroencephalogram, as well as isolated forearm technique and passive brain-computer interface may bring some effects sometimes. Because current studies still have some flaws, further trials with new detecting approach, superior methodology and underlying aetiology are needed to unfasten the possible factors causing awareness.

Bispectral index for improving intraoperative awareness and early postoperative recovery in adults.

BACKGROUND: The use of clinical signs, or end-tidal anaesthetic gas (ETAG), may not be reliable in measuring the hypnotic component of anaesthesia and may lead to either overdosage or underdosage resulting in adverse effects because of too deep or too light anaesthesia. Intraoperative awareness, whilst uncommon, may lead to serious psychological disturbance, and alternative methods to monitor the depth of anaesthesia may reduce the incidence of serious events. Bispectral index (BIS) is a numerical scale based on electrical activity in the brain. Using a BIS monitor to guide the dose of anaesthetic may have advantages over clinical signs or ETAG. This is an update of a review last published in 2014. OBJECTIVES: To assess the effectiveness of BIS to reduce the risk of intraoperative awareness and early recovery times from general anaesthesia in adults undergoing surgery. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, and Web of Science on 26 March 2019. We searched clinical trial registers and grey literature, and handsearched reference lists of included studies and related reviews. SELECTION CRITERIA: We included randomized controlled trials (RCTs) and quasi-RCTs in which BIS was used to guide anaesthesia compared with standard practice which was either clinical signs or end-tidal anaesthetic gas (ETAG) to guide the anaesthetic dose. We included adult participants undergoing any type of surgery under general anaesthesia regardless of whether included participants had a high risk of intraoperative awareness. We included only studies in which investigators aimed to evaluate the effectiveness of BIS for its role in monitoring intraoperative depth of anaesthesia or potential improvements in early recovery times from anaesthesia. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed studies for inclusion, extracted data, and assessed risk of bias. We assessed the certainty of evidence with GRADE. MAIN RESULTS: We included 52 studies with 41,331 participants; two studies were quasi-randomized and the remaining studies were RCTs. All studies included participants undergoing surgery under general anaesthesia. Three studies recruited only participants who were at high risk of intraoperative awareness, whilst two studies specifically recruited an unselected participant group. We analysed the data according to two comparison groups: BIS versus clinical signs; and BIS versus ETAG. Forty-eight studies used clinical signs as a comparison method, which included titration of anaesthesia according to criteria such as blood pressure or heart rate and, six studies used ETAG to guide anaesthesia. Whilst BIS target values differed between studies, all were within a range of values between 40 to 60.BIS versus clinical signsWe found low-certainty evidence that BIS-guided anaesthesia may reduce the risk of intraoperative awareness in a surgical population that were unselected or at high risk of awareness (Peto odds ratio (OR) 0.36, 95% CI 0.21 to 0.60; I2 = 61%; 27 studies; 9765 participants). However, events were rare with only five of 27 studies with reported incidences; we found that incidences of intraoperative awareness when BIS was used were three per 1000 (95% CI 2 to 6 per 1000) compared to nine per 1000 when anaesthesia was guided by clinical signs. Of the five studies with event data, one included participants at high risk of awareness and one included unselected participants, four used a structured questionnaire for assessment, and two used an adjudication process to identify confirmed or definite awareness.Early recovery times were also improved when BIS was used. We found low-certainty evidence that BIS may reduce the time to eye opening by mean difference (MD) 1.78 minutes (95% CI -2.53 to -1.03 minutes; 22 studies; 1494 participants), the time to orientation by MD 3.18 minutes (95% CI -4.03 to -2.33 minutes; 6 studies; 273 participants), and the time to discharge from the postanaesthesia care unit (PACU) by MD 6.86 minutes (95% CI -11.72 to -2 minutes; 13 studies; 930 participants).BIS versus ETAGAgain, events of intraoperative awareness were extremely rare, and we found no evidence of a difference in incidences of intraoperative awareness according to whether anaesthesia was guided by BIS or by ETAG in a surgical population at unselected or at high risk of awareness (Peto OR 1.13, 95% CI 0.56 to 2.26; I2 = 37%; 5 studies; 26,572 participants; low-certainty evidence). Incidences of intraoperative awareness were one per 1000 in both groups. Only three of five studies reported events, two included participants at high risk of awareness and one included unselected participants, all used a structured questionnaire for assessment and an adjudication process to identify confirmed or definite awareness.One large study (9376 participants) reported a reduced time to discharge from the PACU by a median of three minutes less, and we judged the certainty of this evidence to be low. No studies measured or reported the time to eye opening and the time to orientation.Certainty of the evidenceWe used GRADE to downgrade the evidence for all outcomes to low certainty. The incidence of intraoperative awareness is so infrequent such that, despite the inclusion of some large multi-centre studies in analyses, we believed that the effect estimates were imprecise. In addition, analyses included studies that we judged to have limitations owing to some assessments of high or unclear bias and in all studies, it was not possible to blind anaesthetists to the different methods of monitoring depth of anaesthesia.Studies often did not report a clear definition of intraoperative awareness. Time points of measurement differed, and methods used to identify intraoperative awareness also differed and we expected that some assessment tools were more comprehensive than others. AUTHORS' CONCLUSIONS: Intraoperative awareness is infrequent and, despite identifying a large number of eligible studies, evidence for the effectiveness of using BIS to guide anaesthetic depth is imprecise. We found that BIS-guided anaesthesia compared to clinical signs may reduce the risk of intraoperative awareness and improve early recovery times in people undergoing surgery under general anaesthesia but we found no evidence of a difference between BIS-guided anaesthesia and ETAG-guided anaesthesia. We found six studies awaiting classification and two ongoing studies; inclusion of these studies in future updates may increase the certainty of the evidence.

MOTANA: study protocol to investigate motor cerebral activity during a propofol sedation.

BACKGROUND: Accidental Accidental awareness during general anesthesia (AAGA) occurs in 1-2% of high-risk practice patients and is a cause of severe psychological trauma, termed post-traumatic stress disorder (PTSD). However, no monitoring techniques can accurately predict or detect AAGA. Since the first reflex for a patient during AAGA is to move, a passive brain-computer interface (BCI) based on the detection of an intention of movement would be conceivable to alert the anesthetist. However, the way in which propofol (i.e., an anesthetic commonly used for the general anesthesia induction) affects motor brain activity within the electroencephalographic (EEG) signal has been poorly investigated and is not clearly understood. For this reason, a detailed study of the motor activity behavior with a step-wise increasing dose of propofol is required and would provide a proof of concept for such an innovative BCI. The main goal of this study is to highlight the occurrence of movement attempt patterns, mainly changes in oscillations called event-related desynchronization (ERD) and event-related synchronization (ERS), in the EEG signal over the motor cortex, in healthy subjects, without and under propofol sedation, during four different motor tasks. METHODS: MOTANA is an interventional, prospective, exploratory, physiological, monocentric, and randomized study conducted in healthy volunteers under light anesthesia, involving EEG measurements before and after target-controlled infusion of propofol at three different effect-site concentrations (0 µg.ml -1, 0.5 µg.ml -1, and 1.0 µg.ml -1). In this exploratory study, 30 healthy volunteers will perform 50 trials for the four motor tasks (real movement, motor imagery, motor imagery with median nerve stimulation, and median nerve stimulation alone) in a randomized sequence. In each conditions and for each trial, we will observe changes in terms of ERD and ERS according to the three propofol concentrations. Pre- and post-injection comparisons of propofol will be performed by paired series tests. DISCUSSION: MOTANA is an exploratory study aimed at designing an innovative BCI based on EEG-motor brain activity that would detect an attempt to move by a patient under anesthesia. This would be of interest in the prevention of AAGA. TRIAL REGISTRATION: Agence Nationale de Sécurité du Médicament (EUDRACT 2017-004198-1), NCT03362775. Registered on 29 August 2018. https://clinicaltrials.gov/ct2/show/NCT03362775?term=03362775&rank=1.

Effects of neuromuscular blockade reversal on bispectral index and frontal electromyogram during steady-state desflurane anesthesia: a randomized trial.

The degree of neuromuscular blockade reversal may affect bispectral index (BIS) value. One possible reason is that the reverse of neuromuscular blockade affects electromyographic (EMG) signals of fascial muscle. Another reason is, the afferentation theory, the reverse of neuromuscular blockade relieves block signals generated in muscle stretch receptors from accessing the brain through afferent nerve pathways and induces arousal. Inaccurate BIS value may lead to overdose of drugs or the risk of intraoperative awareness. We compared changes in BIS and EMG values according to neuromuscular blockade reversal agents under steady-state desflurane anesthesia. A total of 65 patients were randomly allocated to receive either neostigmine 0.05 mg/kg, sugammadex 4 mg/kg, or pyridostigmine 0.25 mg/kg for neuromuscular blockade reversal under stable desflurane anesthesia, and 57 patients completed the study. The primary outcome was change in BIS and EMG values before and after administration of neuromuscular blockade reversal agents (between train-of-four [TOF] count 1-2 and TOF ratio 0.9). The change in BIS and EMG values before and after administration of neuromuscular blockade reversal agents were statistically different in each group (BIS: Neostigmine group, P < 0.001; Sugammadex group, P < 0.001; Pyridostigmine group, P = 0.001; EMG: Neostigmine group, P = 0.001; Sugammadex group, P < 0.001; Pyridostigmine group, P = 0.001; respectively). The BIS and EMG values had a positive correlation (P < 0.001). Our results demonstrate that the EMG and BIS values have increased after neuromuscular blockade reversal under desflurane anesthesia regardless of the type of neuromuscular blockade reversal agent. BIS should be applied carefully to measure of depth of anesthesia after neuromuscular blockade reversal.

Equipment failure of intravenous syringe pump detected by increase in Narcotrend stage: A case report.

RATIONALE: Awareness is the recovery of consciousness during general anesthesia. It occurs when patients under general anesthesia receive inadequate anesthetic medications to maintain unconsciousness during surgery. Equipment failure is a common cause of intraoperative awareness. PATIENT CONCERNS: A 16-year-old boy, 85 kg in weight, was admitted to our hospital for thyroglossal cystectomy under general anesthesia. Six minutes after the intubation, we noted that the Narcotrend index indicated a condition of light anesthesia and the patient was observed to be in tears. DIAGNOSIS: Improper positioning of the syringe fixing clamp on the CP700TCI infusion pump caused equipment failure and light anesthesia. INTERVENTIONS: Bolus of 50 mg propofol and 2 mg midazolam were administered manually by syringe, and inhalation of 2% sevoflurane was supplemented. Infusion pump was replaced. OUTCOMES: The Narcotrend index of the patient returned to state of deep anesthesia following manual administration of the anesthetic medications. Following the surgery, the patient had an uneventful recovery, and did not present with evidence of awareness. LESSONS: Users of the CP700TCI syringe pump should pay attention to the position of the syringe fixing clamp. Anesthesiologists should check all the equipment according to a defined checklist prior to anesthesia. Narcotrend monitor could help to detect light anesthesia and prevent potential awareness.

Using neuroimaging to uncover awareness in brain-injured and anesthetized patients.

We cast a novel perspective on two distinct populations: patients who become accidentally intraoperatively aware after receiving general anesthesia and severely brain-injured patients who are diagnosed as being in a vegetative state. In both cases, patients are behaviorally non-responsive -and on this basis presumed to lack consciousness- yet, retain covert awareness. In both contexts, detecting consciousness is highly challenging, yet highly important for ensuring adequate patient care. Although great strides have been made in the development of depth-of-anesthesia monitors, these monitors have significant limitations. On the other hand, recent neuroimaging studies on severely brain-injured patients have developed neurobiologically-informed markers of conscious awareness that hold potential for improving monitoring of covert awareness during general anesthesia. Further research is required to determine the implementation of these assessments in the surgical context, and this approach provides promising avenues for improved detection of intraoperative awareness and prevention of accidental awareness under general anesthesia.

Calculations of consciousness: electroencephalography analyses to determine anesthetic depth.

PURPOSE OF REVIEW: Electroencephalography (EEG) was introduced into anesthesia practice in the 1990s as a tool to titrate anesthetic depth. However, limitations in current analysis techniques have called into question whether these techniques improve standard of care, or instead call for improved, more ubiquitously applicable measures to assess anesthetic transitions and depth. This review highlights emerging analytical approaches and techniques from neuroscience research that have the potential to better capture anesthetic transitions to provide better measurements of anesthetic depth. RECENT FINDINGS: Since the introduction of electroencephalography, neuroscientists, engineers, mathematicians, and clinicians have all been developing new ways of analyzing continuous electrical signals. Collaborations between these fields have proliferated several analytical techniques that demonstrate how anesthetics affect brain dynamics and conscious transitions. Here, we review techniques in the following categories: network science, integration and information, nonlinear dynamics, and artificial intelligence. SUMMARY: Up-and-coming techniques have the potential to better clinically define and characterize altered consciousness time points. Such new techniques used alongside traditional measures have the potential to improve depth of anesthesia measurements and enhance an understanding of how the brain is affected by anesthetic agents. However, new measures will be needed to be tested for robustness in real-world environments and on diverse experimental protocols.

Monitoring the end-tidal concentration of sevoflurane for preventing awareness during anesthesia (MEETS-PANDA): A prospective clinical trial.

OBJECTIVE: It was hypothesized that monitoring end-tidal sevoflurane (ETS) during endoscopic surgery could reduce the incidence of intraoperative awareness in patients undergoing general anesthesia. Herein, the incidence of intraoperative awareness and other correlative factors was recorded and compared. METHODS: Two thousand five hundred ASA I-III patients aged 18-80 years who underwent general anesthesia were randomly divided into 2 groups (n = 1250): routine care group (R) and ETS concentration group (E). ETS concentration was monitored in group E and maintained at a sevoflurane minimum alveolar concentration (MAC) of 0.7-1.3; group R was monitored using routine care, and the sevoflurane was maintained. Patients were assessed for intraoperative awareness with a questionnaire on their explicit memory 24-48 h after surgery. RESULTS: A total of 2532 patients were selected, and 86 patients were excluded. As for the groups, 1219 patients were assigned to group E, and 1227 patients were assigned to group R. As for intraoperative awareness, group E had 2 patients, and group R had 14. Compared with group R, the incidence of intraoperative awareness in group E was significantly lower (p = 0.003); the time-averaged ETS concentration and sevoflurane dosage were lower in group E (p < 0.05); and no significant changes were found in tracheal extubation time, intravenous general anesthetic dosage, or postoperative complication incidence in either group (p > 0.05). The incidence of intraoperative awareness was higher in women than men in group R (p < 0.05). CONCLUSION: Using ETS-guided anesthesia and maintaining the sevoflurane concentration (0.7-1.3 MAC) can decrease the incidence of patient awareness during endoscopic surgery.