Anesthetic dreaming, anesthesia awareness and patient satisfaction after deep sedation with propofol target controlled infusion: A prospective cohort study of patients undergoing day case breast surgery

Propofol Dexmedetomidine Total Intravenous Anesthesia with Tumescent Anesthesia in Aesthetic surgery

BACKGROUND

Total intravenous anesthesia (TIVA) is commonly performed in ambulatory aesthetic surgery centers. The authors compared combination of TIVA and tumescent anesthesia for safety and efficacy in prolonged and successive multiple aesthetic procedures.

METHODS

A retrospective review of patients who underwent aesthetic surgery procedures under TIVA from 2016 through 2024 at the authors' aesthetic surgery center was conducted. Patients were included if they fulfilled ASA 1 or 2 staging, BMI < 45 and were of age between 12 and 80 years. Perioperative drug dosages, time under anesthesia and patient vitals were recorded.

RESULTS

Of the 307 patients assessed, 301 completed surgery under TIVA and 6 were converted to GA. No major morbidity was recorded and all 307 cases were discharged from Anesthesia Recovery at 6 hours post-surgery. Average duration of anesthesia time was highest for lipoabdominoplasty (278 min, range 170-360 min). Average dose of tumescent anesthesia was highest in excisional body contouring (2967 ml). No surgical morbidity, e.g., skin necrosis, hematoma and blood transfusion, was reported. No anesthetic morbidity, e.g., deep vein thrombosis, fat embolism and lignocaine toxicity, was reported. Mean arterial pressure and SpO2 were maintained in safe normal range (70-100 mm Hg and > 95%, respectively) up to 6 hours postoperative. Aldrete score for postoperative recovery was > =9 at 10 min for 80% cases (n= 245).

CONCLUSIONS

The analysis of 307 total intravenous anesthesia with tumescent anesthesia cases demonstrated the overall safety and efficacy of the propofol-dexmedetomidine protocol under deep sedation. The study underscores the importance of complete preoperative assessments, vigilant anesthetist-guided drug infusions and monitoring for complications.

LEVEL OF EVIDENCE III

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Non-operating Room Anesthesia (NORA): A Comprehensive Review of Monitored Anesthesia Care

Monitored anesthesia care (MAC) is being increasingly employed in non-operative environments, particularly in the realms of endoscopy and magnetic resonance imaging (MRI) procedures. This in-depth analysis delves into the essential components of MAC within these specific contexts, with a primary focus on ensuring patient safety, evaluating efficacy, and assessing procedural outcomes. It is a common practice in endoscopic procedures to necessitate sedation for the purpose of alleviating discomfort and anxiety, ultimately ensuring patient cooperation and the successful completion of the procedure. MAC, which entails the administration of sedatives and analgesics under the close supervision of an anesthesia professional, offers a personalized approach that carefully balances the depth of sedation with maintaining optimal patient safety standards. Within the domain of MRI procedures, where challenges such as claustrophobia and motion artifacts can significantly impact the process, MAC plays a crucial role in providing a controlled setting that not only enhances image quality but also improves patient compliance throughout the procedure. The review extensively investigates the various pharmacological agents commonly utilized in these scenarios, including but not limited to midazolam and fentanyl, shedding light on their pharmacokinetic and pharmacodynamic properties specific to these contexts. Furthermore, the critical role of the anesthesia provider in effectively managing potential complications, such as respiratory depression, hemodynamic instability, and allergic reactions, is thoroughly examined and discussed. The analysis extends to the implementation of MAC protocols, encompassing pre-procedural assessments, continuous intra-procedural monitoring, and comprehensive post-procedural care, all aimed at ensuring the best possible outcomes for patients. Additionally, the review delves into the economic considerations associated with MAC, taking into account its impact on procedural efficiency, healthcare costs, and patient throughput within these settings. By exploring current guidelines and recommendations established by professional societies such as the American Society of Anesthesiologists (ASA), this review aims to provide a holistic understanding of the best practices in MAC for both endoscopy and MRI procedures. Through the synthesis of available evidence, the primary objective of this review is to contribute to informing clinical practices, enhancing patient safety measures, improving procedural success rates, and ultimately advocating for the broader adoption of monitored anesthesia care in diverse non-operative medical settings.

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.

Subjective experiences during dexmedetomidine- or propofol-induced unresponsiveness and non-rapid eye movement sleep in healthy male subjects

BACKGROUND

Anaesthetic-induced unresponsiveness and non-rapid eye movement (NREM) sleep share common neural pathways and neurophysiological features. We hypothesised that these states bear resemblance also at the experiential level.

METHODS

We compared, in a within-subject design, the prevalence and content of experiences in reports obtained after anaesthetic-induced unresponsiveness and NREM sleep. Healthy males (N=39) received dexmedetomidine (n=20) or propofol (n=19) in stepwise doses to induce unresponsiveness. Those rousable were interviewed and left unstimulated, and the procedure was repeated. Finally, the anaesthetic dose was increased 50%, and the participants were interviewed after recovery. The same participants (N=37) were also later interviewed after NREM sleep awakenings.

RESULTS

Most subjects were rousable, with no difference between anaesthetic agents (P=0.480). Lower drug plasma concentrations were associated with being rousable for both dexmedetomidine (P=0.007) and propofol (P=0.002) but not with recall of experiences in either drug group (dexmedetomidine: P=0.543; propofol: P=0.460). Of the 76 and 73 interviews performed after anaesthetic-induced unresponsiveness and NREM sleep, 69.7% and 64.4% included experiences, respectively. Recall did not differ between anaesthetic-induced unresponsiveness and NREM sleep (P=0.581), or between dexmedetomidine and propofol in any of the three awakening rounds (P>0.05). Disconnected dream-like experiences (62.3% vs 51.1%; P=0.418) and memory incorporation of the research setting (88.7% vs 78.7%; P=0.204) were equally often present in anaesthesia and sleep interviews, respectively, whereas awareness, signifying connected consciousness, was rarely reported in either state.

CONCLUSIONS

Anaesthetic-induced unresponsiveness and NREM sleep are characterised by disconnected conscious experiences with corresponding recall frequencies and content.

CLINICAL TRIAL REGISTRATION

Clinical trial registration. This study was part of a larger study registered at ClinicalTrials.gov (NCT01889004).

Bispectral Index Monitoring and Observer Rating Scale Correlate with Dreaming during Propofol Anesthesia for Gastrointestinal Endoscopies

Background and objectives: Dreaming is a commonly reported side effect of propofol anesthesia. Materials and Methods: We investigated the inci-dence and character of dreams in patients undergoing intravenous propofol anesthesia and cor-related it with an observer rating scale of facial expression on the seven-point scale from pain to smile. A total of 124 patients undergoing gastrointestinal endoscopy were recruited in the pro-spective observational study. Bispectral index (BIS), blood pressure (BP), and pulse were moni-tored. Upon emergence from anesthesia, the patient’s facial expression was rated numerically. Thereafter, patients were asked whether they had dreams and to rate their dreams as pleasant or unpleasant. The mean age of participants was 53; body mass index, 26.17; duration of procedure, 20 min; and average propofol dose, 265 mg. Results: Dreaming was reported by 43% of patients. Dreams were pleasant in all but one patient. There was a significant correlation of the observer’s rating of facial expression with dreaming (r = 0.260; p = 0.004). Dreamers had higher scores of observer rating of facial expression (1 (0–2) vs. 0.5 (0–1), p = 0.006). Conclusions: BIS values were lower in the dreamers vs. non-dreamers 2 min after the endoscopy started (48 (43–62) vs. 59 (45–71), p = 0.038). Both BIS and observer ratings correlate with dreaming in patients undergoing gastrointestinal endos-copy. Trial registration number: NCT04235894.

On no man's land: Subjective experiences during unresponsive and responsive sedative states induced by four different anesthetic agents

To understand how anesthetics with different molecular mechanisms affect consciousness, we explored subjective experiences recalled after responsive and unresponsive sedation induced with equisedative doses of dexmedetomidine, propofol, sevoflurane, and S-ketamine in healthy male participants (N = 140). The anesthetics were administered in experimental setting using target-controlled infusion or vapouriser for one hour. Interviews conducted after anesthetic administration revealed that 46.9% (n = 46) of arousable participants (n = 98) reported experiences, most frequently dreaming or memory incorporation of the setting. Participants receiving dexmedetomidine reported experiences most often while S-ketamine induced the most multimodal experiences. Responsiveness at the end of anesthetic administration did not affect the prevalence or content of reported experiences. These results demonstrate that subjective experiences during responsive and unresponsive sedation are common and anesthetic agents with different molecular mechanisms of action may have different effects on the prevalence and complexity of the experiences, albeit in the present sample the differences between drugs were minute.

Foundations of Human Consciousness: Imaging the Twilight Zone

What happens in the brain when conscious awareness of the surrounding world fades? We manipulated consciousness in two experiments in a group of healthy males and measured brain activity with positron emission tomography. Measurements were made during wakefulness, escalating and constant levels of two anesthetic agents (experiment 1, n = 39), and during sleep-deprived wakefulness and non-rapid eye movement sleep (experiment 2, n = 37). In experiment 1, the subjects were randomized to receive either propofol or dexmedetomidine until unresponsiveness. In both experiments, forced awakenings were applied to achieve rapid recovery from an unresponsive to a responsive state, followed by immediate and detailed interviews of subjective experiences during the preceding unresponsive condition. Unresponsiveness rarely denoted unconsciousness, as the majority of the subjects had internally generated experiences. Unresponsive anesthetic states and verified sleep stages, where a subsequent report of mental content included no signs of awareness of the surrounding world, indicated a disconnected state. Functional brain imaging comparing responsive and connected versus unresponsive and disconnected states of consciousness during constant anesthetic exposure revealed that activity of the thalamus, cingulate cortices, and angular gyri are fundamental for human consciousness. These brain structures were affected independent from the pharmacologic agent, drug concentration, and direction of change in the state of consciousness. Analogous findings were obtained when consciousness was regulated by physiological sleep. State-specific findings were distinct and separable from the overall effects of the interventions, which included widespread depression of brain activity across cortical areas. These findings identify a central core brain network critical for human consciousness.

SIGNIFICANCE STATEMENT Trying to understand the biological basis of human consciousness is currently one of the greatest challenges of neuroscience. While the loss and return of consciousness regulated by anesthetic drugs and physiological sleep are used as model systems in experimental studies on consciousness, previous research results have been confounded by drug effects, by confusing behavioral “unresponsiveness” and internally generated consciousness, and by comparing brain activity levels across states that differ in several other respects than only consciousness. Here, we present carefully designed studies that overcome many previous confounders and for the first time reveal the neural mechanisms underlying human consciousness and its disconnection from behavioral responsiveness, both during anesthesia and during normal sleep, and in the same study subjects.

A randomized control study on anesthetic effects of flurbiprofen axetil combined with propofol on patients with liver cancer receiving microwave ablation

Objective:

To evaluate the anesthetic effects of flurbiprofen axetil combined with propofol on patients with liver cancer receiving microwave ablation.

Methods:

Sixty patients (SA grade: I-II) who underwent microwave ablation for liver cancer in our hospital from May 2018 to May 2019 were selected and randomly divided into a study group and a control group (n=30) that were anesthetized through target-controlled infusion of propofol combined with intravenous infusion of flurbiprofen axetil and target-controlled infusion of propofol alone, respectively. The mean arterial pressure (MAP), heart rate (HR), blood oxygen saturation (SpO₂), numerical rating scale (NRS) score, adverse reactions and anesthetic effects (induction time, recovery time) of the two groups were compared before anesthesia (T0), at the beginning of puncture (T1), at the beginning of microwave ablation (T2), at the end of microwave ablation (T3) and one hour after surgery (T4).

Results:

MAP and HR of the study group were higher than those of the control group (P<0.05) at T2. There was no difference in SpO₂ between the two groups (P>0.05). The anesthesia induction time and recovery time of the study group were significantly shorter than those of the control group (P<0.05). There was no difference in the NRS score between the two groups at T1 (P>0.05), but the study group had lower scores at T2-T4 (P<0.05). The incidence rate of postoperative adverse reactions was 13.33% in the study group and 46.67% in the control group, with a significant difference (P<0.05).

Conclusion:

Flurbiprofen axetil in combination with propofol exert evident anesthetic effects on patients with liver cancer receiving microwave ablation. The time of preoperative anesthesia induction and postoperative recovery time can be markedly shortened, and intraoperative vital signs can be maintained stable. This method is thus worthy of clinical promotion.

Awareness during emergence from anesthesia: Features and future research directions

The anesthesia awareness with recall (AAWR) phenomenon represents a complication of general anesthesia consisting of memorization of intraoperative events reported by the patient immediately after the end of surgery or at a variable distance from it. Approximately 20% of AAWR cases occur during emergence from anesthesia. Clinically, these unexpected experiences are often associated with distress especially due to a sense of paralysis. Indeed, although AAWR at the emergence has multiple causes, in the majority of cases the complication develops when the anesthesia plan is too early lightened at the end of anesthesia and there is a lack of use, or misuse, of neuromuscular monitoring with improper management of the neuromuscular block. Because the distress caused by the sense of paralysis represents an important predictor for the development of severe psychological complications, the knowledge of the phenomenon, and the possible strategies for its prophylaxis are aspects of considerable importance. Nevertheless, a limited percentage of episodes of AAWR cannot be prevented. This paradox holds also during the emergence phase of anesthesia which represents a very complex neurophysiological process with many aspects yet to be clarified.

A new simple score for prediction of difficult laryngoscopy: the EL.GA+ score

BACKGROUND

Preoperative airway assessment plays a key role in the context of difficult airway management. Several scores have been proposed to predict difficult intubation including the el-Ganzouri index (EL.GA). Anatomical parameters such as the opening of the mouth or the circumference of the neck (which currently is not usually evaluated) are used to predict difficult intubation. The nutritional status of super-morbid obesity (body mass index [BMI] > 50 kg m-2) is a recognised risk factor for difficult intubation.

METHODS

This is a single-centre, retrospective, observational study whose aim is to validate an additional parameter (anatomical plus nutritional) to the El.GA index, hence the choice of the acronym for the definition of the study: EL.GA+, in predictivity of airway management; multiple logistic regression analysis was performed to determine the predictive role of BMI, neck circumference and opening of the mouth of intubation difficulty measured with the gold standard.

RESULTS

In total, 240 patients who had an elective surgical procedure under general anaesthesia, requiring endotracheal intubation, were examined. The predictive value of the EL.GA score was confirmed by the values of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) according to the data reported in the literature. Furthermore, based on the values of the PPV and NPV (0.69 and 0.60 respectively), neck circumference of 42.5 cm can be taken as a cut-off value for which EL.GA+ becomes predictive of difficult intubation in patients with mild obesity (BMI of 30 to 35).

CONCLUSIONS

The EL.GA+ score greatly increases the prediction of difficult laryngoscopy in mildly obese patients.

Bispectral index monitoring of sedation depth during endoscopy: a meta-analysis with trial sequential analysis of randomized controlled trials

INTRODUCTION

The Bispectral Index (BIS) provides an objective measure of the level of sedation and general anesthesia. We performed this meta-analysis and trial sequential analysis (TSA) of randomized clinical trials to clarify whether BIS monitoring is helpful in enhancing intraprocedual safety, shortening procedure duration or promoting recovery during sedation for endoscopic procedures.

EVIDENCE ACQUISITION

PubMed, EMBASE, CINAHL, the Cochrane Central Register of Controlled Trials [CENTRAL]) databases, reference lists of articles as well as relevant articles from "Google Scholar" were searched until May 31st, 2018. Randomized controlled trials (RCTs) comparing BIS with clinical signs for titration of sedation depth during endoscopy were screened and identified if they reported one of the following outcome measures: intraprocedual safety (hemodynamic stability and cardiorespiratory complications such as hypoxia, hypertension/hypotension, and bradycardia/tachycardia), procedure duration, recovery time and patient/endoscopist's satisfaction.

EVIDENCE SYNTHESIS

Twelve studies with 13 RCTs recruiting 1372 patients were identified with great inter-trial heterogeneity. Meta-analysis found that BIS monitoring of sedation depth was associated with lower incidences of intraprocedural hypoxia (P=0.009) compared with clinical signs which was not confirmed by TSA. Meta-analysis and TSA found that the endoscopic procedure duration (P=0.143), recovery time (P=0.083), satisfaction scores from both the cases (P=0.085) and endoscopists (P=0.125) and the incidences of hypertension/ hypotension (P=0.639) or heart rates (P=0.201) were similar between BIS and control group.

CONCLUSIONS

More high-quality large-sampled RCTs are needed to confirm whether BIS monitoring for endoscopy sedation helps reduce intraprocedural hypoxia. BIS monitoring fails to shorten procedure duration, promote recovery or boost satisfaction among patients and endoscopists.

Electrodermal Activity Monitoring During Painful Stimulation in Sedated Adult Intensive Care Unit Patients: a Pilot Study

Introduction-Aim: Newer methods, such as infrared digital pupillometry and electrodermal activity (EDA) measurement have been suggested as good alternatives for analgesia monitoring in critically ill patients. This study analyzed EDA changes due to pain stimulus in sedated adult critical care patients Methods: Skin conductance variability, selected hemodynamic and respiratory parameters, Bispectral index (BIS) and ambient noise level, were monitored during 4 hour routine daytime in an adult ICU. 4h-Measurements were divided into 2 groups, based upon the sedation level of the patients: Group A - Ramsay Sedation Score 2-4 and Group B - Ramsay Sedation Score of 5-6. Selected recordings before and after pain stimulus were performed. The stimulus chosen was the pressure applied to nail bed for 10 sec, which was performed routinely during neurological examination. Patients' demographics, laboratory exams and severity scores were recorded. Pain status evaluation before every event was also performed by 2 independent observers via Critical Care Pain Observation Tool (CPOT) and Adult Non Verbal Pain Score (ANVPS) Results: In both groups the rate of EDA changes was greater than other monitoring parameters: more in Group A than in Group B. Yet, the difference between groups was not statistically significant.

CONCLUSION

EDA measurements are greater to pain stimuli, than cardiovascular, respiratory or even BIS monitoring. These encouraging results suggest that, further studies are needed to better define EDA role in ICU.