Intraoperative awareness--comparison of its incidence in women undergoing general anaesthesia for caesarean section and for gynaecological procedures

Influences of Propofol, Ciprofol and Remimazolam on Dreaming During Anesthesia for Gastrointestinal Endoscopy: A Randomized Double-Blind Parallel-Design Trial

Purpose

To compare the influences of propofol, ciprofol and remimazolam on dreaming during painless gastrointestinal endoscopy.

Methods

This study was a single-center, prospective, parallel-design, double-blind, randomized clinical trial. Between May 2023 and October 2023, patients undergoing elective painless gastrointestinal endoscopy were recruited and randomly allocated into one of the three groups. Demographic data, intraoperative information, incidence of dreaming, insufficient anesthesia and intraoperative awareness, type of dream, patient satisfaction score, adverse events, and improvement of sleep quality were collected.

Results

The difference in incidence of dreaming among the three groups was not significant (33.33% vs 48.33% vs 41.67%, p=0.061). The number of patients with intraoperative hypotension in the propofol group was larger than that of the remimazolam group (32 vs 12, p=0.001). However, the cases of intraoperative hypotension between propofol group and ciprofol group or ciprofol group and remimazolam group were comparable (32 vs 22, p=0.122; 22 vs 12, p=0.064). The percentage of insufficient anesthesia between propofol group and remimazolam group was significant (13.33% vs 1.67%, p=0.001), while no statistical difference was detected between propofol group and remimazolam group or ciprofol group and remimazolam group (13.33% vs 5.00%, p=0.025; 5.00% vs 1.67%, p=0.150). The ability of propofol to improve sleep quality at 1st post-examination day was significantly better than that of remimazolam (86.21% vs 72.88%, p=0.015), while it was not significant between propofol group and ciprofol group or ciprofol group and remimazolam group (86.21% vs 80.36%, p=0.236; 72.88% vs. 72.88%, p=0.181). Incidence of intraoperative awareness, intraoperative hypoxia, type of dream, satisfaction score, adverse events during recovery, and sleep improvement on the 7th post-examination day was not significant among the groups.

Conclusion

Anesthesia with propofol, ciprofol and remimazolam, respectively, for gastrointestinal endoscopy did not induce statistical difference in the incidence of dreaming, despite that all of them are more likely to induce pleasant dreams.

Magnesium Sulfate and Clonidine; Effects on Hemodynamic Factors and Depth of General Anesthesia in Cesarean Section

Background

Making stable hemodynamic and also durable unawareness is a daily challenge in the setting of general anesthesia in women who undergo surgical delivery of neonate and have limitations to receive opioids derivatives.

Objectives

We aimed to evaluate the effects of magnesium sulfate and clonidine on hemodynamic changes and depth of anesthesia and in mentioned mothers and also in neonatal APGAR index.

Methods

Current randomized, double-blind controlled trial study was conducted among a total of 360 pregnant females (38 - 41 weeks of gestation) who underwent elective cesarean section. Participants were randomly divided into three drug-receiving groups (equal 120 members): magnesium sulfate (30 mg/kg), clonidine (3 µg/kg), and placebo (0.9% NaCl). Patients’ blood pressure, heart rate, cerebral state index (CSI) in specific time zones, and also late 24-hour recall were recorded. The CSI is an electroencephalographic monitoring method helping to assess the depth of anesthesia. Neonatal parameters, including APGAR score and umbilical venous blood sampling, were measured.

Results

Mean patients’ age was 28 ± 4.5. A significant decreasing and stabilizing effect of magnesium sulfate and clonidine on hemodynamic parameters (blood pressure and heart rate) was revealed (P < 0.001). Evidence implied on deeper anesthesia (lower CSI) among drug receivers comparing to placebo (P < 0.001). None of the participants experienced a late 24-hour recall postoperatively. All neonates were healthy, and no decrease was reported in APGAR score at minutes 1 and 5. Umbilical blood gas analysis showed no signs of acidosis and/or hypoxemia.

Conclusions

Adjuvant administration of either magnesium sulfate or clonidine is associated with hemodynamic stability and favorable unawareness in the setting of elective surgical delivery.

Anaesthetic interventions for prevention of awareness during surgery

BACKGROUND

General anaesthesia is usually associated with unconsciousness. 'Awareness' is when patients have postoperative recall of events or experiences during surgery. 'Wakefulness' is when patients become conscious during surgery, but have no postoperative recollection of the period of consciousness.

OBJECTIVES

To evaluate the efficacy of two types of anaesthetic interventions in reducing clinically significant awareness:- anaesthetic drug regimens; and- intraoperative anaesthetic depth monitors.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, ISSUE 4 2016); PubMed from 1950 to April 2016; MEDLINE from 1950 to April 2016; and Embase from 1980 to April 2016. We contacted experts to identify additional studies. We performed a handsearch of the citations in the review. We did not search trial registries.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) of either anaesthetic regimens or anaesthetic depth monitors. We excluded volunteer studies, studies of patients prior to skin incision, intensive care unit studies, and studies that only randomized different word presentations for memory tests (not anaesthetic interventions).Anaesthetic drug regimens included studies of induction or maintenance, or both. Anaesthetic depth monitors included the Bispectral Index monitor, M-Entropy, Narcotrend monitor, cerebral function monitor, cerebral state monitor, patient state index, and lower oesophageal contractility monitor. The use of anaesthetic depth monitors allows the titration of anaesthetic drugs to maintain unconsciousness.

DATA COLLECTION AND ANALYSIS

At least two authors independently scanned abstracts, extracted data from the studies, and evaluated studies for risk of bias. We made attempts to contact all authors for additional clarification. We performed meta-analysis statistics in packages of the R language.

MAIN RESULTS

We included 160 studies with 54,109 enrolled participants; 53,713 participants started the studies and 50,034 completed the studies or data analysis (or both). We could not use 115 RCTs in meta-analytic comparisons because they had zero awareness events. We did not merge 27 of the remaining 45 studies because they had excessive clinical and methodological heterogeneity. We pooled the remaining 18 eligible RCTs in meta-analysis. There are 10 studies awaiting classification which we will process when we update the review.The meta-analyses included 18 trials with 36,034 participants. In the analysis of anaesthetic depth monitoring (either Bispectral Index or M-entropy) versus standard clinical and electronic monitoring, there were nine trials with 34,744 participants. The overall event rate was 0.5%. The effect favoured neither anaesthetic depth monitoring nor standard clinical and electronic monitoring, with little precision in the odds ratio (OR) estimate (OR 0.98, 95% confidence interval (CI) 0.59 to 1.62).In a five-study subset of Bispectral Index monitoring versus standard clinical and electronic monitoring, with 34,181 participants, 503 participants gave awareness reports to a blinded, expert panel who adjudicated or judged the outcome for each patient after reviewing the questionnaires: no awareness, possible awareness, or definite awareness. Experts judged 351 patient awareness reports to have no awareness, 87 to have possible awareness, and 65 to have definite awareness. The effect size favoured neither Bispectral Index monitoring nor standard clinical and electronic monitoring, with little precision in the OR estimate for the combination of definite and possible awareness (OR 0.96, 95% CI 0.35 to 2.65). The effect size favoured Bispectral Index monitoring for definite awareness, but with little precision in the OR estimate (OR 0.60, 95% CI 0.13 to 2.75).We performed three smaller meta-analyses of anaesthetic drugs. There were nine studies with 1290 participants. Wakefulness was reduced by ketamine and etomidate compared to thiopental. Wakefulness was more frequent than awareness. Benzodiazepines reduces awareness compared to thiopental, ketamine, and placebo., Also, higher doses of inhaled anaesthetics versus lower doses reduced the risk of awareness.We graded the quality of the evidence as low or very low in the 'Summary of findings' tables for the five comparisons.Most of the secondary outcomes in this review were not reported in the included RCTs.

AUTHORS' CONCLUSIONS

Anaesthetic depth monitors may have similar effects to standard clinical and electrical monitoring on the risk of awareness during surgery. In older studies comparing anaesthetics in a smaller portion of the patient sample, wakefulness occurred more frequently than awareness. Use of etomidate and ketamine lowered the risk of wakefulness compared to thiopental. Benzodiazepines compared to thiopental and ketamine, or higher doses of inhaled anaesthetics versus lower doses, reduced the risk of awareness.