Ti3C2Tx-rGO-chitosan-based microcatheter sensor for real-time continuous monitoring of propofol: toward improved anesthetic management

We are aiming to develop an electrochemical microcatheter sensor for the detection and real-time continuous monitoring of propofol (PPF), which is an anesthetic drug majorly used during medical treatment. This proposed microcatheter-based sensing strategy meets the challenge of real-time periodic and continuous monitoring of propofol by using d-Ti3C2Tx-rGO-chi-modified carbon paste microcatheter sensor transducer. The sensing methodology relies on voltammetry and chronoamperometry transduction methods. The reusable microcatheter sensor was fabricated by embedding the three electrodes into a few millimeters-wide Teflon tube. The nanocomposite was characterized using advanced analytical instruments such as XRD, FE-SEM, EDX, Raman spectroscopy, and XPS. Further, electrode interfacial properties were characterized with voltammetry and electrochemical impedance spectroscopy. The electroanalytical performance of the modified microcatheter sensor was tested for the detection of PPF in phosphate buffer by using chronoamperometry with a wide linear range of 5 to 110 µM (at an applied potential of 0.3 V vs. Ag/AgCl). The sensor's practical potency was confirmed in human serum with a dynamic linear range of 10 to 130 µM. The sensor exhibited a good limit of detection values in phosphate buffer (2 µM) and natural human plasma (4 µM). The new sensor displays different dimensions of information while displaying high sensitivity, selectivity, and long-term stability. The outstanding analytical performance of the developed sensor holds considerable promise for the continuous monitoring of propofol, its effective management, and optimization of the doses in the patient's body.

Awake surgery for glioma resection during pregnancy: a systematic review

Brain tumors are rarely present during pregnancy. However, they can severely impact the fetus and mother's well-being due to a complex interaction of disease and physiological factors. Moreover, awake surgery for gliomas has been scarcely reported during this life stage, and the nuances and techniques merit further investigation. Herein, we performed a systematic review of the literature about awake surgery for glioma resection during pregnancy. A total of six patients with a median age of 30.5 years (interquartile range: 40-27) were analyzed. Awake surgery was performed in the third trimester in 50% of patients (median time: 24.5 weeks) without reported intraoperative complications. Conscious sedation was achieved by remifentanil and propofol infusion in 67% of cases, and intraoperative fetal heart monitoring was utilized in 83% of cases. Most studies revealed good clinical maternal-fetal outcomes at follow-up; however, long-term safety effects remain undetermined and warrant further research. In conclusion, awake surgery for glioma resection under a multidisciplinary approach can be a reasonable treatment option for select patients during pregnancy.

The efficacy of non-anesthesiologist-administered propofol sedation with a target-controlled infusion system during double-balloon endoscopic retrograde cholangiopancreatography

BACKGROUND

The sedation method used during double-balloon endoscopic retrograde cholangiopancreatography (DB-ERCP) differs among countries and/or facilities, and there is no established method. This study aimed to evaluate the efficacy of non-anesthesiologist-administered propofol (NAAP) sedation using a target-controlled infusion (TCI) system during DB-ERCP.

METHODS

This retrospective study was conducted between May 2017 and December 2020 at an academic center. One hundred and fifty-six consecutive patients who underwent DB-ERCP were sedated by gastroenterologists using diazepam (n = 77) or propofol with a TCI system (n = 79), depending on the period. The primary endpoint was a comparison of poor sedation rates between the two groups. Poor sedation was defined as a condition requiring the use of other sedative agents or discontinuation of the procedure. Secondary endpoints were sedation-related adverse events and risk factors for poor sedation.

RESULTS

Poor sedation occurred significantly more often in the diazepam sedation group (diazepam sedation, n = 12 [16%] vs. propofol sedation, n = 1 [1%]; P = 0.001). Vigorous body movements (3 or 4) (diazepam sedation, n = 40 [52%] vs. propofol sedation, n = 28 [35%]; P = 0.038) and hypoxemia (< 85%) (diazepam sedation, n = 7 [9%] vs. propofol sedation, n = 1 [1%]; P = 0.027) occurred significantly more often in the diazepam sedation group. In the multivariate analysis, age < 70 years old (OR, 10.26; 95% CI, 1.57-66.98; P = 0.015), BMI ≥ 25 kg/m2 (OR, 11.96; 95% CI, 1.67-85.69; P = 0.014), and propofol sedation (OR, 0.06; 95% CI, 0.01-0.58; P = 0.015) were associated factors for poor sedation.

CONCLUSIONS

NAAP sedation with the TCI system during DB-ERCP was safer and more effective than diazepam sedation.

Recovery Benefit With Total Intravenous Anesthesia in Patients Receiving Rhinoplasty

OBJECTIVE

The aim was to evaluate the difference in recovery when comparing total intravenous anesthesia (TIVA) to inhalational gas anesthesia in patients receiving rhinoplasty.

STUDY DESIGN

Retrospective review.

SETTING

Postoperative anesthesia care unit (PACU).

METHODS

Patients who received a functional or cosmetic rhinoplasty at a single academic institution between April 2017 and November 2020 were included. Inhalational gas anesthesia was in the form of sevoflurane. Phase I recovery time, which was defined as the time it took a patient to reach ≥9/10 on the Aldrete scoring system was recorded, as well as the usage of pain medication in the PACU. The postoperative course and incidence of postoperative nausea and vomiting (PONV) were also collected.

RESULTS

Two hundred and two patients were identified with 149 (73.76%) who received TIVA and 53 (26.24%) who received sevoflurane. For the patients who received TIVA, the average recovery time was 101.44 minutes (standard deviation [SD]: 34.64) compared to an average recovery time of 121.09 minutes (SD: 50.19) for patients who received sevoflurane leading to a difference of 19.65 minutes (p = 0.002). Patients who received TIVA experienced less PONV (p = 0.001). There were no differences in the postoperative course including surgical or anesthesia complications, postoperative complications, hospital or Emergency Department admissions, or administration of pain medication (p > 0.05 for all).

CONCLUSION

When utilizing TIVA over inhalational anesthesia, patients undergoing rhinoplasty had significantly increased benefits in terms of reduced phase I recovery times and decreased incidence of PONV. TIVA was demonstrated to be a safe and efficacious method of anesthesia for this patient population.

Continuous and deep sedation until death after a decision to withdraw life-sustaining therapies in intensive care units: A national survey

BACKGROUND

Continuous and deep sedation until death is a much highly debated end-of-life practice. France is unique in having a regulatory framework for it. However, there are no data on its practice in intensive care units (ICUs).

AIM

The aim is to describe continuous and deep sedation in relation to the framework in the specific context of withdrawal of life-sustaining therapies in ICUs, that is, its decision-making process and its practice compared to other end-of-life practices in this setting.

DESIGN AND SETTING

French multicenter observational study. Consecutive ICU patients who died after a decision to withdraw life-sustaining therapies.

RESULTS

A total of 343 patients in 57 ICUs, 208 (60%) with continuous and deep sedation. A formalized procedure for continuous and deep sedation was available in 32% of the ICUs. Continuous and deep sedation was not the result of a collegial decision-making process in 17% of cases, and did not involve consultation with an external physician in 29% of cases. The most commonly used sedative medicines were midazolam (10 [5-18] mg h-1) and propofol (200 [120-250] mg h -1). The Richmond Agitation Sedation Scale (RASS) was -5 in 60% of cases. Analgesia was associated with sedation in 94% of cases. Compared with other end-of-life sedative practices (n = 98), medicines doses were higher with no difference in the depth of sedation.

CONCLUSIONS

This study shows a poor compliance with the framework for continuous and deep sedation. It highlights the need to formalize it to improve the decision-making process and the match between the intent, the practice and the actual effect.

Does Lidocaine Shorten Seizure Duration in Electroconvulsive Therapy?

BACKGROUND

Electroconvulsive therapy (ECT) is an effective short-term treatment for schizophrenia and depression, amongst other disorders. Lidocaine is typically added to reduce pain from intravenous propofol injection. However, depending on the dose used in the ECT setting, it can shorten seizure duration. The aim of this study was to investigate the effect of lidocaine dose on seizure duration.

METHODS

This retrospective, naturalistic cohort study included 169 patients treated with ECT. We examined 4714 ECT sessions with propofol or propofol plus lidocaine. Ictal quality was manually rated by visual inspection. The main outcome of this study was the relation of lidocaine with seizure duration after controlling for socio-demographic, ECT, and other anesthetic variables.

RESULTS

There was a significant negative association between lidocaine usage and seizure duration. Multivariate analyses showed that seizure duration was shortened by an average of 3.21 s in sessions with lidocaine. Moreover, in this subgroup, there was a significant negative dose-dependent association between lidocaine dose and seizure length. Complementarily, a significant positive association between preictal BIS and seizure length was found in the subgroup of sessions where preictal was used.

CONCLUSIONS

We provide additional evidence highlighting the importance of caution regarding lidocaine dosing due to the effect on seizure length in the ECT setting. It is advisable for clinicians to exercise caution when administering lidocaine regarding its dosing and seizure length in ECT settings. Future investigation is needed to assess causal relationships by studying certain vulnerable groups or employing other charge calculation techniques, such as the titration method.

Positional Change Used to Manage Postextubation Respiratory Failure in a Child With Cerebral Palsy

Dental treatment for patients with cerebral palsy (CP) is often performed under general anesthesia due to involuntary movements that can render dental treatment difficult. Since CP is often accompanied by spasticity, care must be taken when positioning patients during general anesthesia. We report the management of a 14-year-old girl with CP and epilepsy undergoing general anesthesia for dental treatment who experienced respiratory failure due to acute thoracoabdominal muscle hypertonia after extubation. She had a history of cardiac arrest due to respiratory failure caused by acute muscle hypertonia and successful resuscitation. General anesthesia was induced after careful positioning of the patient to prevent spastic muscle stretching, and the dental treatment was completed without complications. However, upon awakening after extubation, the patient developed respiratory failure due to acute muscle hypertonia. The patient was resedated and repositioned from a supine to a sitting position, and her symptoms improved. There was no recurrence of muscle hypertonia, and she recovered fully without complications. In this case, respiratory failure associated with acute muscle hypertonia was successfully managed by position change after initial treatment with positive-pressure ventilation and propofol. It is important to be prepared for the possibility of respiratory failure associated with acute muscle hypertonia and its countermeasures when providing general anesthesia for patients with CP.

Effect of Dexmedetomidine and Two Different Doses of Esketamine Combined Infusion on the Quality of Recovery in Patients Undergoing Modified Radical Mastectomy for Breast Cancer - A Randomised Controlled Study

Purpose

This study evaluated the effect of a combined infusion of dexmedetomidine and esketamine on the quality of recovery in patients undergoing modified radical mastectomy.

Methods

A total of 135 patients were randomly divided into three groups: dexmedetomidine group (group D) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion), dexmedetomidine plus low-dose esketamine group (group DE1) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion) and esketamine (0.5 mg/kg loading, 2 µg/kg/min infusion), dexmedetomidine plus high-dose esketamine group (group DE2) received dexmedetomidine (0.5 µg/kg loading, 0.4 µg/kg/h infusion) and esketamine (0.5 mg/kg loading, 4 µg/kg/min infusion). The primary outcome was the overall quality of recovery-15 (QoR-15) scores at 1 day after surgery. The secondary endpoints were total QoR-15 scores at 3 days after surgery, propofol and remifentanil requirement, awaking and extubation time, postoperative visual analogue scale (VAS) pain scores, rescue analgesic, nausea and vomiting, bradycardia, excessive sedation, nightmares, and agitation.

Results

The overall QoR-15 scores were much higher in groups DE1 and DE2 than in groups D 1 and D 3 days after surgery (P < 0.05). VAS pain scores at 6, 12, 24 h postoperatively, propofol and remifentanil requirements were significantly lower in groups DE1 and DE2 than in group D (P < 0.05). Compared with group D, awaking time, extubation time, and post-anesthesia care unit (PACU) stay were significantly prolonged in groups DE1 and DE2 (P < 0.05) and were much longer in group DE2 than in group DE1 (P < 0.05). The proportion of postoperative rescue analgesics and bradycardia was higher and the incidence of excessive sedation was lower in group D than in groups DE1 and DE2 (P < 0.05).

Conclusion

Dexmedetomidine plus esketamine partly improved postoperative recovery quality and decreased the incidence of bradycardia but prolonged awaking time, extubation time, and PACU stay, especially dexmedetomidine plus 4 µg/kg/min esketamine.

A Transformer-Based Prediction Method for Depth of Anesthesia During Target-Controlled Infusion of Propofol and Remifentanil

Accurately predicting anesthetic effects is essential for target-controlled infusion systems. The traditional (PK-PD) models for Bispectral index (BIS) prediction require manual selection of model parameters, which can be challenging in clinical settings. Recently proposed deep learning methods can only capture general trends and may not predict abrupt changes in BIS. To address these issues, we propose a transformer-based method for predicting the depth of anesthesia (DOA) using drug infusions of propofol and remifentanil. Our method employs long short-term memory (LSTM) and gate residual network (GRN) networks to improve the efficiency of feature fusion and applies an attention mechanism to discover the interactions between the drugs. We also use label distribution smoothing and reweighting losses to address data imbalance. Experimental results show that our proposed method outperforms traditional PK-PD models and previous deep learning methods, effectively predicting anesthetic depth under sudden and deep anesthesia conditions.

The study of different dosages of remazolam combined with sufentanil and propofol on painless gastroscopy: A randomized controlled trial

BACKGROUND

Gastroscopy is one of the most commonly used diagnostic modalities for upper gastrointestinal disorders. Remazolam besylate, a new type of ultrashort-acting benzodiazepine drug, has been less studied in gastroscopy. In this study, we studied the efficacy and safety of remazolam combined with propofol for painless gastroscopy.

METHODS

This is a single-center, randomized controlled clinical trial. Hundred patients undergoing painless gastroscopy were included in this study and randomly divided into 2 groups (n = 50 per group): the remazolam 3 mg group (R3 group) and the remazolam 6 mg group (R6 group). Sufentanil, remazolam, and propofol are used to anesthetize the patients, and then, the effects of different dosages of remazolam on these patients are compared and analyzed. The patient's general condition, vital signs at different times, the dosage of propofol (mg) and additional times, complications, duration of gastroscopy (minute), awakening time (minute), residence time in the resuscitation room (minute), and adverse reactions were recorded.

RESULTS

R3 group systolic blood pressure and diastolic blood pressure are more stable (P < .05); The number of additional propofol in R6 group was less (P < .05). The incidence of hypotension was lower in R3 group, as well as the time of awakening and staying in the resuscitation room were shorter (P < .05).

CONCLUSION

Remazolam 3mg combined with sufentanil and propofol have less effect on hemodynamics in painless gastroscopy, and the patients have shorter awakening time.

Influence of ventilatory parameters on the concentration of exhaled volatile organic compounds in mechanically ventilated patients

Analysis of volatile organic compounds (VOC) within exhaled breath is subject to numerous sources of methodological and physiological variability. Whilst breathing pattern is expected to influence the concentrations of selected exhaled VOCs, it remains challenging to investigate respiratory rate and depth accurately in awake subjects. Online breath sampling was performed in 20 mechanically ventilated patients using proton transfer reaction time-of-flight mass spectrometry (PTR-ToF-MS). The effect of variation in respiratory rate (RR) and tidal volume (TV) on the VOC release profiles was examined. A panel of nineteen VOCs were selected, including isoprene, acetone, propofol, volatile aldehydes, acids and phenols. Variation in RR had the greatest influence on exhaled isoprene levels, with maximum and average concentrations being inversely correlated with RR. Variations in RR had a statistically significant impact on acetone, C3-C7 linear aldehydes and acetic acid. In comparison, phenols (including propofol), C8-C10 aldehydes and C3-C6 carboxylic acids were not influenced by RR. Isoprene was the only compound to be influenced by variation in TV. These findings, obtained under controlled conditions, provide useful guidelines for the optimisation of breath sampling protocols to be applied on awake patients.

Intravenous Lidocaine Decreased the Median Effective Concentration of Sufentanil for Tracheal Intubation in Obese Patients

Purpose

Sufentanil has been widely used to inhibit the hemodynamic responses caused by tracheal intubation. Using intravenous lidocaine may reduce the dose of sufentanil and better maintain the hemodynamics. This study aimed to determine the effects of intravenous lidocaine on the median effective concentration (EC50) of sufentanil for endotracheal intubation in obese patients.

Patients and Methods

This is a randomized, double-blind, up-and-down sequential allocation study. Fifty obese patients undergoing bariatric surgery were randomly allocated in a 1:1 ratio into the lidocaine group and the saline group. Anesthesia was induced using a target-controlled infusion of propofol and sufentanil. The effect-site concentration (Ce) of propofol was 3.5 μg/mL. The Ce of sufentanil for the first patient was 0.4 ng/mL, and the sufentanil dose for the next patient was determined according to the responses of the previous patient, using Dixon's up-and-down sequential method with an interval of 0.05 ng/mL. When the target concentration of propofol and sufentanil was reached, lidocaine 1.5 mg/kg or the same volume of normal saline was infused over 3 min. Tracheal intubation was performed 3 min after the end of the lidocaine or normal saline infusion. Probit regression was used to calculate the EC50 and 95% confidence interval (CI) of sufentanil.

Results

Thirty-eight patients completed this study. The EC50 of sufentanil was 0.36 ng/mL (95% CI: 0.31-0.41 ng/mL) in the lidocaine group, which was significantly lower than 0.50 ng/mL (95% CI: 0.43-0.62 ng/mL) in the saline group. In addition, compared with saline group, the dosage of sufentanil in lidocaine group decreased significantly during the test. The hemodynamics of the two groups were stable during the study period.

Conclusion

Intravenous lidocaine 1.5 mg/kg decreased the EC50 of sufentanil required for tracheal intubation in obese patients undergoing bariatric surgery.

Anesthesia management of patients undergoing thoracic endovascular aortic repair: A retrospective analysis of single center

Thoracic endovascular aortic repair (TEVAR) is a new alternative surgical treatment for aortic pathologies, which is more minimally invasive. The aim of current study was to summarize the single-center experience of general anesthesia for patients undergoing TEVAR. In adult patients undergoing surgery for congenital heart disease, the strategy of "fast-track" anesthesia with early extubation in theater is associated with a shorter intensive care unit (ICU) stay, and lower health-care-related costs. Fast-track anesthesia has not been assessed in patients under TEVAR. Adult patients who received general anesthesia for TEVAR in our center from January 2020 to December 2020 were included. Baseline characteristics, airway management, anesthetic techniques and major complications were collected. A total of 204 (171 male, mean age 58.1 ± 11.5 years) patients met inclusion criteria for this study. The distribution of pathologies included 29 descending thoracic aneurysms, 87 type B dissections, and 88 intramural hematoma/perforating aortic ulcer. Etomidate was the induction agent in 190 (93.1%) patients, compared with propofol in 16 (7.8%). Cisatracurium was the muscle relaxant in 201 (98.5%), compared with rocuronium in 3 (1.5%). Midazolam (benzodiazepines) was given to 124 (60.8%) patients during anesthesia induction. General anesthesia was maintained with sevoflurane in 85.3% (174) patients, dexmedetomidine in 201 (98.5%) and propofol in 204 (100%). Postoperative length of stay (LOS) in the hospital was 6.0 (5.0-7.8) days. LOS in the ICU was 23.0 (20.0-27.8) hours. Overall neurologic event rate was 2.0% (n = 4) (spinal cord ischemia 1.5% [n = 3]; stroke 0.5% [n = 1]). After matching, patients who received "fast-track" anesthesia had a shorter LOS in ICUs (21.0 [18.0-24.0] vs 24.0 [20.0-44.0] hours; P = .005), and a shorter postoperative LOS in hospital (5.0 [4.0-7.0] vs 6.0 [5.0-8.0] days; P = .001). There were no in-hospital deaths. Fast-track anesthesia is feasible and safe in patients underwent TEVAR. This management strategy is associated with shorter LOS of ICU and total postoperative hospital stays. An early extubation strategy should be implemented for hemodynamically stable patients.

Prospective, randomized, double-blind, double-dummy, active-controlled, phase 3 clinical trial comparing the safety and efficacy of intranasal dexmedetomidine to oral midazolam as premedication for propofol sedation in pediatric patients undergoing magnetic resonance imaging: the MIDEX MRI trial

BACKGROUND

Children under 6 years who need magnetic resonance imaging usually require sedation to obtain best quality images, but the optimal sedation protocol remains to be determined. In 2018, we showed a 22% interruption in image acquisition during magnetic resonance imaging when performing a propofol-based sedation using a bolus approach. As non-pharmacological premedication is often insufficient to reduce the anxiety of children related to parental separation, pharmacological premedication may be useful to facilitate the induction of anesthesia. In our institution, effective premedication is obtained oral intake of midazolam, though its administration relies on patients' compliance and could also lead to paradoxical reaction. Dexmedetomidine has a safe profile in the pediatric population and can therefore represent an interesting alternative. The primary objective of this trial is to demonstrate the superiority of intranasal dexmedetomidine compared to oral midazolam as premedication in reducing the occurrence of any event requiring temporary or definitive interruption of the examination to allow anesthesiologist intervention in children undergoing magnetic resonance imaging under propofol sedation.

METHODS

In this single-center, prospective, randomized, double-blind, double-dummy, active comparator-controlled, superiority trial, we planned to include 250 patients, aged 6 months to 6 years, undergoing a scheduled magnetic resonance imaging requiring the presence of an anesthesiologist. After informed consent, the patients will be randomized to receive either oral midazolam or intranasal dexmedetomidine as premedication. The data will be analyzed in intention to treat, using Kolmogorov-Smirnov Z, chi-square, Wilcoxon, and Mann-Whitney U tests. A P-value < 0.05 will be considered statistically significant.

DISCUSSION

The MIDEX MRI study will assess the efficacy of intranasal dexmedetomidine compared to oral midazolam to improve the quality of a propofol-based sedation prior to magnetic resonance imaging, without negative repercussion on the postoperative period.

TRIAL REGISTRATION

ClinicalTrial.gov NCT05192629 . Registered on 14 January 2022. Protocol version 2.1.

Comparison of nasotracheal versus orotracheal intubation for sedation, assisted spontaneous breathing, mobilization, and outcome in critically ill patients: an exploratory retrospective analysis

Nasotracheal intubation (NTI) may be used for long term ventilation in critically ill patients. Although tracheostomy is often favored, NTI may exhibit potential benefits. Compared to orotracheal intubation (OTI), patients receiving NTI may require less sedation and thus be more alert and with less episodes of depression of respiratory drive. We aimed to study the association of NTI versus OTI with sedation, assisted breathing, mobilization, and outcome in an exploratory analysis. Retrospective data on patients intubated in the intensive care unit (ICU) and ventilated for > 48 h were retrieved from electronic records for up to ten days after intubation. Outcome measures were a Richmond Agitation and Sedation Scale (RASS) of 0 or - 1, sedatives, vasopressors, assisted breathing, mobilization on the ICU mobility scale (ICU-MS), and outcome. From January 2018 to December 2020, 988 patients received OTI and 221 NTI. On day 1-3, a RASS of 0 or - 1 was attained in OTI for 4.0 ± 6.1 h/d versus 9.4 ± 8.4 h/d in NTI, p < 0.001. Propofol, sufentanil, and norepinephrine were required less frequently in NTI and doses were lower. The NTI group showed a higher proportion of spontaneous breathing from day 1 to 7 (day 1-6: p < 0.001, day 7: p = 0.002). ICU-MS scores were higher in the NTI group (d1-d9: p < 0.001, d10: p = 0.012). OTI was an independent predictor for mortality (odds ratio 1.602, 95% confidence interval 1.132-2.268, p = 0.008). No difference in the rate of tracheostomy was found. NTI was associated with less sedation, more spontaneous breathing, and a higher degree of mobilization during physiotherapy. OTI was identified as an independent predictor for mortality. Due to these findings a new prospective evaluation of NTI versus OTI should be conducted to study risks and benefits in current critical care medicine.

Anaesthesia, analgesia, and cancer outcomes: time to think like oncologists?

Cao and colleagues present a follow-up analysis of a previous RCT among >1200 older adults (mean age 72 yr) undergoing cancer surgery, originally designed to evaluate the effect of propofol or sevoflurane general anaesthesia on delirium, here to evaluate the effect of anaesthetic technique on overall survival and recurrence-free survival. Neither anaesthetic technique conferred an advantage on oncological outcomes. We suggest that although it is entirely plausible that the observed results are truly robust neutral findings, the present study could be limited, like most published studies in the field, by its heterogeneity and understandable absence of underlying individual patient-specific tumour genomic data. We argue for a precision oncology approach to onco-anaesthesiology research that recognises that cancer is not one but rather many diseases and that tumour genomics (and multi-omics) is a fundamental determinant relating drugs to longer-term outcomes.

Volatile versus intravenous anaesthesia and perioperative neurocognitive disorders: anything to see here?

There is a potential differential effect of sevoflurane compared with propofol on postoperative delirium and other perioperative neurocognitive disorders. More generally, there are perhaps differences between volatile and intravenous anaesthetic agents in their possible impact on perioperative neurocognitive disorders. Strengths and limitations of a recent study in this journal and its contribution to our understanding of the impact of anaesthetic technique on perioperative neurocognitive disorders are discussed.

How obesity affects the disposition of intravenous anesthetics

PURPOSE OF REVIEW

Understanding the changes in drug disposition of intravenous anesthetics in patients with obesity and administering appropriate doses are critical to avoid intraoperative awareness with recall because of underdosing and over-sedation and delayed emergence due to overdosing. Pharmacokinetic simulation or target-controlled infusion (TCI) using models that have been adapted to patients with obesity are necessary to select appropriate dosing regimens. This review aimed to describe the pharmacokinetic concepts underpinning the use of intravenous anesthetics, including propofol, remifentanil, and remimazolam, in patients with obesity.

RECENT FINDINGS

In the last 5 years, a series of pharmacokinetic models for propofol, remifentanil, and remimazolam that were estimated from populations that included obese patients have been published. These new pharmacokinetic models can be considered 'second generation' compared with earlier models in that they expand the range of covariate effects (e.g. the extremes of body weight and age) accounted for by the models. The predictive performances of each pharmacokinetic model have been shown in the literature to be within clinically acceptable limits. Among them, the propofol model by Eleveld et al. has been externally validated and has shown reasonable predictive accuracy.

SUMMARY

Pharmacokinetic simulations or TCI using pharmacokinetic models that account for the influence of obesity on a drug's disposition are essential to predict plasma/effect-site concentrations of intravenous anesthetics and understand the temporal profile of drug concentrations and effect in patients with obesity, particularly severe obesity.

Comparison of remimazolam and propofol induction on hemodynamic response in hypertensive patients

BACKGROUND

Hemodynamic variations during the induction of general anesthesia are more profound in hypertensive patients, and the risk of hypoperfusion-induced organ damage followed by hypotensive episodes is higher in hypertensive patients than in normotensive patients. Thus, we compared the effects of remimazolam and propofol on hemodynamics during general anesthesia induction in hypertensive patients.

METHODS

Patients were randomly divided into the remimazolam (Group R, n = 48) and propofol (Group P, n = 48) groups: remimazolam was continued at 6 mg/kg/hour until the patient lost consciousness, followed by 1 mg/kg/hour until 5 minutes after tracheal intubation. Propofol was administered as a slow bolus of 1.5 to 2 mg/kg, followed by 3 to 6 mg/kg/hour 5 minutes after tracheal intubation. Hemodynamic parameters including mean blood pressure (MBP), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate, and incidence of hypotension were analyzed during the induction period, pre-induction (T1), immediately after loss of consciousness (T2), at 1 and 3 minutes after neuromuscular blockade (T3, T4), immediately after tracheal intubation (T5), and at 1, 3, and 5 minutes after tracheal intubation (T6, T7, T8).

RESULTS

The MBP, SBP, and DBP were significantly lower in the propofol group than in the remimazolam group (MBP: at T2, T3, T4, and T5; SBP: at T2, T3, and T4; DBP: at T5). HR was significantly lower in the propofol group at T3, T4, and T8. The incidence of hypotension was significantly higher in the propofol group than that in the remimazolam group. The incidence of bradycardia was comparable between the groups.

CONCLUSIONS

Remimazolam induction was more stable than propofol induction in preserving normal hemodynamics and was associated with a relatively lower incidence of hypotension. Remimazolam may be preferable to propofol for induction of anesthesia in patients with hypertension.

The Impact of Sedative Choice on Intracranial and Systemic Physiology in Moderate to Severe Traumatic Brain Injury: A Scoping Review

Although sedative use is near-ubiquitous in the acute management of moderate to severe traumatic brain injury (m-sTBI), the evidence base for these agents is undefined. This review summarizes the evidence for analgosedative agent use in the intensive care unit management of m-sTBI. Clinical studies of sedative and analgosedative agents currently utilized in adult m-sTBI management (propofol, ketamine, benzodiazepines, opioids, and alpha-2 agonists) were identified and assessed for relevance and methodological quality. The primary outcome was the effect of the analgosedative agent on intracranial pressure (ICP). Secondary outcomes included intracranial hemodynamic and metabolic parameters, systemic hemodynamic parameters, measures of therapeutic intensity, and clinical outcomes. Of 594 articles identified, 61 met methodological review criteria, and 40 were included in the qualitative summary; of these, 33 were prospective studies, 18 were randomized controlled trials, and 8 were blinded. There was consistent evidence for the efficacy of sedative agents in the management of m-sTBI and raised ICP, but the overall quality of the evidence was poor, consisting of small studies (median sample size, 23.5) of variable methodological quality. Propofol and midazolam achieve the goals of sedation without notable differences in efficacy or safety, although high-dose propofol may disrupt cerebral autoregulation. Dexmedetomidine and propofol/ dexmedetomidine combination may cause clinically significant hypotension. Dexmedetomidine was effective to achieve a target sedation score. De novo opioid boluses were associated with increased ICP and reduced cerebral perfusion pressure. Ketamine bolus and infusions were not associated with increased ICP and may reduce the incidence of cortical spreading depolarization events. In conclusion, there is a paucity of high-quality evidence to inform the optimal use of analgosedative agents in the management of m-sTBI, inferring significant scope for further research.

Outcomes and evaluation of endoscopic retrograde cholangiopancreatography via Gastro-Laryngeal Tube in adult patients: a prospective randomised control study

OBJECTIVES

In conventional endoscopic retrograde cholangiopancreatography (ERCP), the patient lies prone or in a semi-prone position under deep sedation and maintains spontaneous ventilation. Sedative-induced respiratory depression and unprotected airway compromise patients' safety. The gastro-laryngeal tube (G-LT) is a novel reusable supraglottic airway device with two separate ports for endoscopy and ventilation. This study attempts to evaluate the performance characteristic of G-LT.

METHODS

One hundred and forty patients undergoing ERCP were enrolled and randomized. In Group G, patients underwent ERCP with G-LT, whereas Group S patients underwent ERCP conventionally. G-LT insertion attempts, esophageal visualization times, vital parameters, propofol consumption, endoscopists' and anesthesiologists' satisfaction scores, time to achieve Modified Aldrete Score of ≥ 9, and complications were recorded.

RESULTS

Both groups showed similar demographic parameters and 100% procedure completion rates. G-LT group showed shortened esophageal visualization times (4.71 ± 1.687 s vs 7.37 ± 1.515 s) and increased propofol consumption (423.14 ± 106.982 mg vs 178.00 ± 100.125 mg). Group G showed better endoscopic maneuvrability and lesser hemodynamic variability. Sore throat, dysphagia, and mucosal trauma were higher in the G-LT group.

CONCLUSION

G-LT provides less intra-procedural hemodynamic changes, quicker esophageal visualization, and better scope maneuvrability at the cost of higher propofol consumption, sore throat, dysphagia, and mucosal trauma.

TRIAL REGISTRATION

Clinical Trial Registry of India CTRI/2021/06/034212 (Registered on: 14/06/2021).

Effects of Sevoflurane and Propofol on Neurological Recovery of Traumatic Brain Injury Patients in the Early Postoperative Stage: A Retrospective Cohort Study

Objective To investigate the effects of propofol and sevoflurane on neurological recovery of traumatic brain injury (TBI) patients in the early postoperative stage.Methods We retrospectively analyzed the clinical data of TBI patients who underwent craniotomy or decompressive craniectomy. Generalized additive mixed model (GAMM) was used to analyze effects of propofol and sevoflurane on Glasgow Coma Scale (GCS) on postoperative days 1, 3, and 7. Multivariate regression analysis was used to analyze effects of the two anesthetics on Glasgow Outcome Scale (GOS) at discharge.Results A total of 340 TBI patients were enrolled in this study. There were 110 TBI patients who underwent craniotomy including 75 in the propofol group and 35 in the sevoflurane group, and 134 patients who underwent decompressive craniectomy including 63 in the propofol group and 71 in the sevoflurane group. It showed no significant difference in GCS at admission between the propofol and the sevoflurane groups among craniotomy patients (β = 0.75, 95%CI: -0.55 to 2.05, P = 0.260). However, elevation in GCS from baseline was 1.73 points (95%CI: -2.81 to -0.66, P = 0.002) less in the sevoflurane group than that in the propofol group on postoperative day 1, 2.03 points (95%CI: -3.14 to -0.91, P < 0.001) less on day 3, and 1.31 points (95%CI: -2.43 to -0.19, P = 0.022) less on day 7. The risk of unfavorable GOS (GOS 1, 2, and 3) at discharge was higher in the sevoflurane group (OR = 4.93, 95%CI: 1.05 to 23.03, P = 0.043). No significant difference was observed among two-group decompressive craniectomy patients in GCS and GOS.Conclusions Compared to propofol, sevoflurane was associated with worse neurological recovery during the hospital stay in TBI patients undergoing craniotomy. This difference was not detected in TBI patients undergoing decompressive craniectomy.

Comparison of bispectral index and patient state index as measures of sedation depth during surgeries using remimazolam tosilate

BACKGROUND

The Bispectral Index (BIS) and the Patient State Index (PSI) are commonly used measures to assess intraoperative sedation depth. However, model differences lead to different results, which in turn interferes with clinicians' judgment on the depth of anesthesia. Remimazolam tosilate (RT) for injection is a new benzodiazepine used in sedation. In its clinical application, there are few effective indicators for sedation depth monitoring. To close this gap, this study aims to compare BIS and PSI in measuring the sensitivity and specificity of intraoperative RT and to explore the safety of RT for intraspinal anesthesia in elderly patients.

METHODS

This study included 40 patients undergoing elective electro-prostatectomy with intraspinal anesthesia, who were monitored by BIS and PSI simultaneously during operation. Remimazolam tosylate 0.1 mg/kg was intravenously administered after the intraspinal anesthesia when patients were in a completely painless status. Then BIS, PSI, the Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scores and vital signs were observed and recorded per minute for 10 min. Pearson's correlation analysis and linear regression model were used to compare BIS and PSI sedation scores, and to test their associations with the MOAA/S score, respectively. ROC curves were drawn to compare the sensitivity and specificity of BIS and PSI. Changes of vital signs were presented as mean ± standard deviation. Perioperative liver and kidney function indicators were analyzed using a paired t-test to evaluate the safety of RT for intraspinal anesthesia in the elderly patients.

RESULTS

According to Pearson's correlation analysis, a significant (P < 0.01) correlation between BIS and PSI was found when used to monitor intraoperative sedation of RT (r = 0.796). Significant associations between BIS and MOAA/S (r = 0.568, P < 0.01), and between PSI and MOAA/S (r = 0.390, P < 0.01) were also found. The areas under the ROC curves of BIS and PSI were 0.801 ± 0.022 and 0.734 ± 0.026, respectively, suggesting that both measures may predict patients' state of consciousness and BIS was more accurate than PSI. Vital signs remained stable throughout the study. No abnormal changes of clinical significance were found based on laboratory test results of liver and kidney function.

CONCLUSION

BIS and PSI are strongly associated for monitoring the sedation of RT intraoperatively. Both methods can accurately reflect sedation depth. According to correlation analyses with MOAA/S scale and ROC curves, BIS is more accurate than PSI during such intraoperative monitoring. In addition, RT can be safely used in elderly patients under intraspinal anesthesia for supportive sedation, with stable vital signs and sound kidney and liver safety profiles.

TRIAL REGISTRATION

http://www.chictr.org.cn (ChiCTR2100051912).

Anesthetic Management Using Remimazolam in a Hemodialysis Patient

Remimazolam, an ultra-short-acting benzodiazepine, is a new intravenous anesthetic used for sedation and general anesthesia. Because remimazolam is primarily metabolized by carboxylesterases in the liver and other tissues including the lung and has metabolites with little or no bioactivity, its anesthetic effect is not significantly influenced by renal dysfunction. Therefore, remimazolam may be considered an appropriate agent for hemodialysis patients and may have added benefits beyond midazolam and propofol. Remimazolam has also been suggested to cause less cardiac depression than propofol. This case report presents an 82-year-old female hemodialysis patient with chronic heart failure who underwent partial glossectomy for squamous cell carcinoma of the tongue under general anesthesia with remimazolam and remifentanil. Hemodynamic control was stable during the anesthetic, which was safely completed without any adverse events and resulted in a rapid, clear emergence without flumazenil. Remimazolam and remifentanil may be appropriate as first-line general anesthetic agents for hemodialysis patients with heart failure.

Automated Closed-Loop Propofol Anesthesia Versus Desflurane Inhalation Anesthesia in Obese Patients Undergoing Bariatric Surgery: A Comparative Randomized Analysis of Recovery Profile

INTRODUCTION

Precision general anesthesia (GA) techniques that minimize the presence of residual anesthetic and facilitate recovery, are desirable in patients with morbid obesity. Automated administration of propofol total intravenous anesthesia (TIVA), which facilitates precision propofol delivery by factoring in continuous patient input variable (bispectral index) to establish a closed feedback loop system, may help mitigate concerns related to propofol's lipid solubility and adverse accumulation kinetics in patients with morbid obesity. This randomized study evaluated the recovery of patients with morbid obesity undergoing bariatric surgery under propofol TIVA automated by a closed-loop anesthesia delivery system (CLADS) versus desflurane GA.

METHODS

Forty patients, randomly allocated to receive propofol TIVA (CLADS group) or desflurane GA (desflurane group), were evaluated for postoperative recovery (early and intermediate) (primary objective); they were evaluated for intraoperative hemodynamics, anesthesia depth consistency, anesthesia delivery performance characteristics, patient satisfaction, and incidence of adverse events (sedation, pain, postoperative nausea, and vomiting) (secondary objective).

RESULTS

No difference was found for the time-to-eye-opening (CLADS group: 4.7 [3.0, 6.7] min vs. desflurane group: 5.6 [4.0, 6.9] min, P = 0.576), time-to-tracheal-extubation (CLADS group: 6.7 [4.7, 9.3] min vs. desflurane group: 7.0 [5.8, 9.2] min, P = 0.528), ability-to-shift score from operating room table to the transport bed (CLADS group: 3 [3.0, 3.5] vs. desflurane group: 3 [3.0, 4.0], P = 0.703), and time to achieve a modified Aldrete score 9/10 (CLADS group: 15 [15.0, 37.5] min vs. desflurane group: 15 [15.0, 43.7] min, P = 0.867).

CONCLUSION

Automated propofol TIVA as administered by CLADS, which matched desflurane GA with respect to depth of anesthesia consistency and postanesthesia recovery profile, can be explored further as an alternative anesthesia technique in patients with morbid obesity.

Automated Closed-Loop Propofol Anesthesia Versus Desflurane Inhalation Anesthesia in Obese Patients Undergoing Bariatric Surgery: A Comparative Randomized Analysis of Recovery Profile

INTRODUCTION

Precision general anesthesia (GA) techniques that minimize the presence of residual anesthetic and facilitate recovery, are desirable in patients with morbid obesity. Automated administration of propofol total intravenous anesthesia (TIVA), which facilitates precision propofol delivery by factoring in continuous patient input variable (bispectral index) to establish a closed feedback loop system, may help mitigate concerns related to propofol's lipid solubility and adverse accumulation kinetics in patients with morbid obesity. This randomized study evaluated the recovery of patients with morbid obesity undergoing bariatric surgery under propofol TIVA automated by a closed-loop anesthesia delivery system (CLADS) versus desflurane GA.

METHODS

Forty patients, randomly allocated to receive propofol TIVA (CLADS group) or desflurane GA (desflurane group), were evaluated for postoperative recovery (early and intermediate) (primary objective); they were evaluated for intraoperative hemodynamics, anesthesia depth consistency, anesthesia delivery performance characteristics, patient satisfaction, and incidence of adverse events (sedation, pain, postoperative nausea, and vomiting) (secondary objective).

RESULTS

No difference was found for the time-to-eye-opening (CLADS group: 4.7 [3.0, 6.7] min vs. desflurane group: 5.6 [4.0, 6.9] min, P = 0.576), time-to-tracheal-extubation (CLADS group: 6.7 [4.7, 9.3] min vs. desflurane group: 7.0 [5.8, 9.2] min, P = 0.528), ability-to-shift score from operating room table to the transport bed (CLADS group: 3 [3.0, 3.5] vs. desflurane group: 3 [3.0, 4.0], P = 0.703), and time to achieve a modified Aldrete score 9/10 (CLADS group: 15 [15.0, 37.5] min vs. desflurane group: 15 [15.0, 43.7] min, P = 0.867).

CONCLUSION

Automated propofol TIVA as administered by CLADS, which matched desflurane GA with respect to depth of anesthesia consistency and postanesthesia recovery profile, can be explored further as an alternative anesthesia technique in patients with morbid obesity.

Evaluation of Sedation Levels Using SedLine During Intravenous Sedation for Dental Procedures: A Case-Series Study

The Patient State Index (PSI) is the numerical value of anesthesia depth as measured using a SedLine Sedation Monitor (Masimo Corporation). In this pilot study, we evaluated PSI values captured during intravenous (IV) moderate sedation for dental treatment. During the dental treatment, a dental anesthesiologist maintained the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score at 3 to 4 by adjusting the administration of midazolam and propofol while PSI values were recorded. The mean (SD) and median (25th percentile, 75th percentile) PSI values during dental treatment under IV moderate sedation were 72.7 (13.6) and 75 (65, 85), respectively.

Electroconvulsive Therapy Anesthetic Choice and Clinical Outcomes

OBJECTIVE

Etomidate and methohexital are the 2 commonly used anesthetics for electroconvulsive therapy (ECT) in the United States. The objective of this study was to examine how anesthetic choice between etomidate and methohexital is associated with real-world clinical outcomes.

METHODS

This naturalistic retrospective cohort study examined longitudinal electronic health records for 495 adult patients who received 2 or more ECT treatments from 2010 to 2019 in Kaiser Permanente North California, a large integrated health care system. Study outcomes included 12-month posttreatment depression remission as measured by the 9-item Patient Health Questionnaire, psychiatric and all-cause emergency department visits, and psychiatric and all-cause hospitalizations.

RESULTS

Anesthetic choice was not significantly related to depression severity, emergency department visits, or psychiatric hospitalizations at 12 months after completing ECT. In exploratory analyses, we found that etomidate compared with methohexital was associated with higher rates of patient discomfort adverse effects-postictal agitation, phlebitis, and myoclonus (2.4% vs 0.4%; P < 0.001).

CONCLUSIONS

We present the first large comparison of etomidate and methohexital as anesthetics for ECT and their associations with real-world outcomes. Our study showed no significant difference on depression remission, emergency department visits, or hospitalizations 12-months posttreatment. Thus, clinicians should focus on other patient or treatment characteristics when deciding on anesthetics for ECT. Further investigation is needed to confirm our exploratory findings that etomidate use was correlated with a higher rate of patient discomfort adverse effects relative to methohexital.

Micellar Encapsulation of Propofol Reduces its Adsorption on Extracorporeal Membrane Oxygenator (ECMO) Circuit

Extracorporeal membrane oxygenation (ECMO) is a life-saving cardiopulmonary bypass device used on critically ill patients with refractory heart and lung failure. Patients supported with ECMO receive numerous drugs to treat critical illnesses and the underlying diseases. Unfortunately, most drugs prescribed to patients on ECMO lack accurate dosing information. Dosing can be variable in this patient population because the ECMO circuit components can adsorb drugs and affect drug exposure substantially. Propofol is a widely used anesthetic in ECMO patients and is known to have high adsorption rates in ECMO circuits due to its high hydrophobicity. In an attempt to reduce adsorption, we encapsulated propofol with Poloxamer 407 (Polyethylene-Polypropylene Glycol). Size and polydispersity index (PDI) were characterized using dynamic light scattering. Encapsulation efficiency was analyzed using High performance liquid chromatography. Cytocompatibility of micelles was analyzed against human macrophages and the formulation was finally injected in an ex-vivo ECMO circuit to determine the adsorption of propofol. Size and PDI of micellar propofol were 25.5 ± 0.8 nm and 0.08 ± 0.01, respectively. Encapsulation efficiency of the drug was 96.1 ± 1.3%. Micellar propofol demonstrated colloidal stability at physiological temperature for a period of 7 days, and was cytocompatible with human macrophages. Micellar propofol demonstrated a significant reduction in adsorption of propofol in the ECMO circuit at earlier time points compared to free propofol (Diprivan®). We observed 97 ± 2% recovery of the propofol from the micellar formulation after an infusion. These results demonstrate the potential of micellar propofol to reduce drug adsorption to ECMO circuit.

Dexmedetomidine alleviates propofol-induced pyroptosis of hippocampal neurons through NLRP3 inflammasome pathway

Propofol is neurotoxic to trigger neuronal pyroptosis and dexmedetomidine possesses the ability to suppress proptosis. This study expounded on the protective functions of dexmedetomidine on propofol-induced pyroptosis of primary hippocampal neurons via NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome pathway. At first, primary hippocampal neurons underwent separation and identification and were treated with different concentrations of propofol (1, 10, and 100 μM). The toxicity of propofol in the neurons was evaluated. Prior to propofol treatment, the neurons were treated with different concentrations of dexmedetomidine (0.01, 0.1, 1, 5, and 10 μM). The viability of neurons with different treatments was detected. The mRNA expressions of homeobox A5 (HOXA5) and NLRP3 were identified. The protein levels of intracellular HOXA5, NLRP3, the N-terminal fragment of gasdermin D (GSDMD-N), and cleaved-caspase-1 and the concentrations of interleukin (IL)-1β and IL-18 were examined. Subsequently, the binding of HOXA5 to the NLRP3 promoter was detected. Joint experiments were conducted with pcDNA3.1-HOXA5 or pcDNA3.1-NLRP3 in dexmedetomidine-treated neurons. Dexmedetomidine pretreatment attenuated propofol-induced pyroptosis of hippocampal neurons, increased cell viability, and repressed NLRP3, GSDMD-N, and cleaved-caspase-1 protein levels and IL-1β and IL-18 concentrations. Dexmedetomidine pretreatment inhibited intracellular HOXA5 expression, and HOXA5 bound to the NLRP3 promoter region to promote NLRP3 expression. Overexpressing HOXA5 or NLRP3 reversed anti-pyroptosis role of dexmedetomidine pretreatment in hippocampal neurons. Dexmedetomidine pretreatment suppressed NLRP3 expression by downregulating HOXA5 expression, inhibiting propofol-induced pyroptosis in primary hippocampal neurons.

Rethink analgo-sedation in digestive endoscopy: the role of scientific societies in tracing training path

OBJECTIVE

The Italian Society of Anesthesia, Analgesia, Reanimation and Intensive Care Medicine (SIAARTI) and the Italian Society of Digestive Endoscopy (SIED) worked together to produce a joint Good Clinical Practice (GCP) on analgo-sedation in digestive endoscopy and launched a survey to support the document. The aim was to identify and describe the actual clinical practice of sedation in Italian digestive endoscopy units and offer material for a wider and more widespread discussion among anesthetists and endoscopists.

SUBJECTS AND METHODS

A national survey was planned, in order to support the statements of the GCP. Twelve thousand and five hundred questionnaires were sent to the members of SIAARTI and SIED in June 2020.

RESULTS

A total of 662 forms (5.3%) returned completed. Highly complex procedures are performed according to 70% of respondents; daily anesthesiologist's assistance is guaranteed in 26%, for scheduled sessions in 14.5% and as needed in 8%. 69% of respondents declared not to have a dedicated team of anesthesiologists, while just 5% reported an anesthesiologist in charge. A complete monitoring system was assured by 70% of respondents. Dedicated pathways for COVID-19-positive patients were confirmed in <40% of the answers. With regard to moderate/deep sedation, 90% of respondents stated that an anesthetist decides timing and doses. Propofol was exclusively administered by anesthetists according to 94% of answers, and for 6% of respondents the endoscopist is allowed to administer propofol in presence of a dedicated nurse, but with a readily available anesthetist. Only 32.8% of respondents reported institutional training courses on procedural analgo-sedation.

CONCLUSIONS

The need to provide patients scheduled for endoscopy procedures with an adequate analgo-sedation is becoming an increasing concern, well-known in almost all countries, but many factors compromise the quality of patient care. Results of a national survey would give strength to the need for a shared GCP in gastrointestinal endoscopy. Training and certification of non-anesthetist professionals should be one of the main ways to center the objective.

Development and evaluation of an anatomically designed and 3D printed device to enhance orotracheal intubation success in rabbits by inexperienced veterinarians

OBJECTIVE

To assess whether the use of a three-dimensional (3D) printed device enhances the success rate of orotracheal intubation in rabbits.

STUDY DESIGN

Prospective, crossover randomized controlled trial.

ANIMALS

A total of six mixed-breed rabbits.

METHODS

A device to guide the endotracheal tube was designed based on computed tomography images and then manufactured using 3D printing. Rabbits were randomly assigned for intubation by two inexperienced veterinarians using the blind (BLI), borescope- (BOR) or device- (DEV) guided techniques. Success rate, number of attempts, time to success, injury scores and propofol dose were recorded and compared. Significance was considered when p < 0.05.

RESULTS

Success rate was higher in DEV (58.3%) than in BLI (8.3%) (p < 0.023), but not different from that in BOR (41.6%). Total time until successful intubation was lower in DEV (45 ± 23 seconds) and BOR (85 ± 62 seconds) than in BLI (290 seconds; p < 0.006). Time for the successful attempt was lower for DEV (35 ± 10 seconds) and BOR (74 ± 43 seconds) than in BLI (290 seconds; p < 0.0001). The propofol dose required was lower for DEV (2.3 ± 1.2 mg kg-1) than for BLI (3.4 ± 1.6 mg kg-1) (p < 0.031), but not different from BOR (2.4 ± 0.9 mg kg-1). Number of attempts and oxygen desaturation events were not different among techniques (p < 0.051 and p < 0.326, respectively). Injury scores [median (range)] before and after attempts were different in BLI [0 versus 1 (0-3), p < 0.005] and BOR [0 (0-1) versus 1 (0-3), p < 0.002] but not in DEV [0 (0-2) versus 0 (0-3), p < 0.109].

CONCLUSIONS AND CLINICAL RELEVANCE

The device facilitated orotracheal intubation with a time similar to the borescope-guided technique but faster than the traditional blind technique.

Perioperative management and drug selection for sedated/anesthetized patients undergoing MRI examination: A review

In recent years, magnetic resonance imaging (MRI) technology has become an indispensable imaging tool owing to significant improvements in MRI that have opened up new diagnostic perspectives. Due to the closed environment, long imaging time, and need to remain still during the examination process, the examiner may cannot cooperate with the completion of the examination of the procedure, which increases the need for deep sedation or anesthesia. Achieving this can sometimes be challenging, especially in the special nontraditional environment of MRI equipment (unfamiliar and narrow spaces, away from patients, strong magnetic fields) and in special populations requiring sedation/anesthesia during examinations, which pose certain challenges for the perioperative anesthesia management of MRI. A simple "checklist" is necessary because it allows the anesthesiologist to become familiar with the particular environment and human and material resources as quickly as possible. For the choice of sedative/anesthetic, the traditional drugs, such as midazolam and ketamine, are still used due to the ease of administration despite their low sedation success rate, prolonged recovery, and significant adverse events. Currently, dexmedetomidine, with respiratory drive preservation, propofol, with high effectiveness and rapid recovery, and sevoflurane, which is mild and nonirritating, are preferred for sedation/anesthesia in children and adults undergoing MRI. Therefore, familiarity with the perioperative management of patient sedation and general anesthesia and drug selection in the MRI environment is critical for successful surgical completion and for the safe and rapid discharge of MRI patients receiving sedation/anesthesia.

Humidity and measurement of volatile propofol using MCC-IMS (EDMON)

The bedside Exhaled Drug MONitor - EDMON measures exhaled propofol in ppbv every minute based on multi-capillary column - ion mobility spectrometry (MCC-IMS). The MCC pre-separates gas samples, thereby reducing the influence of the high humidity in human breath. However, preliminary analyses identified substantial measurement deviations between dry and humid calibration standards. We therefore performed an analytical validation of the EDMON to evaluate the influence of humidity on measurement performance. A calibration gas generator was used to generate gaseous propofol standards measured by an EDMON device to assess linearity, precision, carry-over, resolution, and the influence of different levels of humidity at 100% and 1.7% (without additional) relative humidity (reference temperature: 37°C). EDMON measurements were roughly half the actual concentration without additional humidity and roughly halved again at 100% relative humidity. Standard concentrations and EDMON values correlated linearly at 100% relative humidity (R²=0.97). The measured values were stable over 100min with a variance ≤ 10% in over 96% of the measurements. Carry-over effects were low with 5% at 100% relative humidity after 5min of equilibration. EDMON measurement resolution at 100% relative humidity was 0.4 and 0.6 ppbv for standard concentrations of 3 ppbv and 41 ppbv. The influence of humidity on measurement performance was best described by a second-order polynomial function (R²≥0.99) with influence reaching a maximum at about 70% relative humidity. We conclude that EDMON measurements are strongly influenced by humidity and should therefore be corrected for sample humidity to obtain accurate estimates of exhaled propofol concentrations.

Clinical effect of different doses of ciprofol for induction of general anesthesia in elderly patients: A randomized, controlled trial

Ciprofol is a newly developed intravenous anesthetic agent with improved pharmacokinetic properties. Compared to propofol, ciprofol exhibits stronger binding to the GABAA receptor and elicits a greater enhancement of GABAA receptor-mediated neuronal currents in vitro. The aims of the present clinical trials were to examine the safety and efficacy of different doses of ciprofol for induction of general anesthesia in elderly patients. A total of 105 elderly patients undergoing elective surgery were randomized, in a 1:1:1 ratio, to receive one of three sedation regimens: (1) the C1 group (0.2 mg/kg ciprofol), (2) the C2 group (0.3 mg/kg ciprofol), (3) the C3 group (0.4 mg/kg ciprofol). The primary outcome was the incidence of various adverse events, including hypotension, hypertension, bradycardia, tachycardia, hypoxemia, and injection pain. The secondary outcomes of efficacy were the success rate of general anesthesia induction, the time to anesthesia induction, and the frequency of remedial sedation was recorded in each group. Adverse events occurred in 13 patients (37%) in group C1, 8 patients (22%) in group C2, and 24 patients (68%) in group C3. Compared with group C2, the total incidence of adverse events was significantly higher in group C1 and group C3 (p < .001).The success rate of general anesthesia induction in the three groups was 100%. Compared with group C1, the frequency of remedial sedation was significantly lower in group C2 and group C3. The outcomes demonstrated that ciprofol at a dose of 0.3 mg/kg has good safety and efficacy in the induction of general anesthesia in elderly patients. Overall, ciprofol is a new and viable option for the induction of general anesthesia in elderly patients undergoing elective surgery.

Etomidate-ketamine versus dexmedetomidine-ketamine for entropy-guided procedural sedation during endoscopic retrograde cholangiopancreatography procedures: A randomized single blind study

BACKGROUND AND AIMS

The major challenge for the anesthetist in endoscopic retrograde cholangiopancreatography (ERCP) procedures is to provide moderate to deep levels of sedation in prone position with preservation of spontaneous respiratory efforts in shared airway scenario with an endoscopist. These patients have other comorbidities, making them vulnerable to complications during the routinely used sedation with propofol. We compared the entropy-guided efficacy of combination of etomidate-ketamine to dexmedetomidine-ketamine in patients undergoing ERCP.

METHODS

This prospective single blind randomized entropy-guided trial was conducted on 60 patients with etomidate-ketamine in group I (n = 30) and dexmedetomidine-ketamine in group II (n = 30). The purpose was to compare etomidate-ketamine versus dexmedetomidine-ketamine for ERCP in terms of intraprocedural hemodynamics with desaturation, onset of sedation, recovery time and endoscopist's satisfaction.

RESULTS

Hypotension was observed only in six (20%) patients of group II (p < 0.009). Two patients of group I and three in group II desaturated (Spo2 < 90) briefly during the procedure, but none of the patient required intubation (p > 0.05). The mean time in minutes of onset of sedation was 1.15 in group I and 5.6 in group II (p < 0.001). Endoscopists' satisfaction was better in group I (p ≤ 0.001) and length of recovery room stay was shorter in group I as compared to that in group II (p ≤ 0.007).

CONCLUSION

We conclude that entropy-guided intravenous procedural sedation with etomidate-ketamine combination provides faster onset of sedation, stable periprocedural hemodynamics, rapid recovery and fair to excellent endoscopist satisfaction compared to dexmedetomidine-ketamine combination for ERCP.

Comparison of missed adenomas in deep-sedated and unsedated colonoscopy: A multicenter retrospective study

BACKGROUND

Deep-sedated colonoscopy with propofol is widely used in China. However, its impact on quality metrics remains controversial. We aimed to investigate the effects of deep-sedated colonoscopy on missed adenomas, specifically in each colorectal segment.

METHODS

Data of 3710 individuals from seven hospitals in China who underwent an initial colonoscopy with or without propofol sedation and a second colonoscopy without sedation within six months for surveillance or polypectomy by endoscopist of the same level between October 2020 and September 2021 were retrospectively analyzed.

RESULTS

A total of 1113 missed adenomas in 3710 patients were evaluated. The adenoma miss rate (AMR) was significantly higher in deep-sedated colonoscopy than in unsedated colonoscop [19.14% (578/3020) vs. 16.15% (535/3313), P < 0.05]. The risk of missing adenomas in deep-sedated colonoscopy was 1.229 times higher than in unsedated colonoscopy (OR, 1.229; 95% CI: 1.080-1.399). AMRs of the splenic flexure (26.02% [96/369] vs. 16.04% [47/293], P < 0.05) and descending colon (20.86% [102/489] vs. 13.37% [54/404], P < 0.05) were significantly higher in deep-sedated colonoscopy than in unsedated colonoscopy when performed by middle-level endoscopists rather than high-level endoscopists (P < 0.05).

CONCLUSIONS

AMR was higher in deep-sedated colonoscopy than in unsedated colonoscopy. Furthermore, adenomas in the splenic flexure and descending colon were more frequently missed in deep-sedated colonoscopy than in unsedated colonoscopy, particularly when performed by less experienced endoscopists.

Insights into the spectrofluorometric determination of the neuromuscular blocker mivacurium chloride

Fluorescence spectroscopy is gaining interest in the analysis and quantitative determination of different drugs. This study was carried out to investigate the fluorometric properties of the short-acting muscle relaxant mivacurium in its pure form, injection, and human plasma. It is nondepolarizing skeletal muscle relaxant for intravenous (IV) administration. Mivacurium shows a strong native fluorescence in methanol at 317 nm after excitation at 230 nm (Method I). The critical parameters that may influence the fluorescence of this drug were carefully studied. A linear response between concentration and fluorescence was constructed over the concentration range: 20.0 to 400.0 ng/mL with determination coefficient (r²) equal to 0.9998. Additionally, the correlation coefficient of the linear relationship (r) was found to be 0.9999 with a slope = 2.196 and intercept = -16.61. Limits of quantitation and detection were calculated mathematically to be 17.45 and 5.75 ng/mL respectively. Further estimation of mivacurium in spiked human plasma was performed by construction of specific calibration curve and the obtained correlation coefficient was 0.9948. Moreover, the ability to determine mivacurium in the presence of commonly co-administered drugs were investigated including propofol and thiopental. Method II includes the determination of MVC in the presence of propofol utilizing the first derivative synchronous fluorescence spectroscopy. The results of method II indicated acceptable percentage recoveries from 98.88 to 100.75 %. Statistical evaluation of the results revealed satisfactory accuracy and precision.

Effect of low-dose propofol combined with dexamethasone on the prevention of postoperative nausea and vomiting in gynaecological day surgery under remimazolam-based general anesthesia

BACKGROUND

To observe the effect of low-dose propofol combined with dexamethasone on the prevention of postoperative nausea and vomiting (PONV) in gynaecological day surgery under remimazolam-based general anesthesia.

METHODS

A total of 120 patients, aged from 18 to 65 years old, American Society of Anesthesiologists grade I or II, were scheduled to undergo hysteroscopy under total intravenous anesthesia. The patients were divided into 3 groups (n = 40 each): dexamethasone plus saline group (DC group), dexamethasone plus droperidol group (DD group) and dexamethasone plus propofol group (DP group). Dexamethasone 5 mg and flurbiprofen axetil 50 mg were given intravenously before induction of general anesthesia. Anesthesia induction: remimazolam 6 mg/kg/hours was continuously pumped until sleep and slow intravenous injection of alfentanil 20 ug/kg and mivacurium chloride 0.2 mg/kg was given. Anesthesia maintenance: remimazolam 1 mg/kg/hour and alfentanil 40 ug/kg/hours were continuously pumped. After the start of surgery, DC group was given 2 mL saline, DD group was given droperidol 1 mg, and DP group was given propofol 20 mg. Primary outcome: incidence of PONV in the postanesthesia care unit (PACU). Secondary outcome: incidence of PONV in patients within 24 hours after surgery, as well as general patient data, duration of anesthesia, the recovery time of patients, dose of remimazolam and alfentanil, etc.

RESULTS

In PACU, patients of group DD and DP showed less PONV than those in group DC (P < .05). Within 24 hours after operation, there was no significant difference in the incidence of PONV among the 3 groups (P > .05), but the incidence of vomiting in DD group and DP group was significantly lower than that in DC group (P < .05). There was no significant difference in general data, anesthesia time, the recovery time of patients and dosage of remimazolam and alfentanil among the 3 groups (P > .05).

CONCLUSION

The effect of low-dose propofol combined with dexamethasone to prevent PONV under remimazolam-based general anesthesia was similar to that of droperidol combined with dexamethasone, both of which significantly reduced the incidence of PONV in the PACU compared to dexamethasone alone. However, low-dose propofol combined with dexamethasone had little effect on the incidence of PONV within 24 hours compared to dexamethasone alone and only reduced the incidence of postoperative vomiting in patients.

Modern Sedation and Analgesia Strategies in Neurocritical Care

PURPOSE OF REVIEW

Patients with acute neurologic injury require a specialized approach to critical care, particularly with regard to sedation and analgesia. This article reviews the most recent advances in methodology, pharmacology, and best practices of sedation and analgesia for the neurocritical care population.

RECENT FINDINGS

In addition to established agents such as propofol and midazolam, dexmedetomidine and ketamine are two sedative agents that play an increasingly central role, as they have a favorable side effect profile on cerebral hemodynamics and rapid offset can facilitate repeated neurologic exams. Recent evidence suggests that dexmedetomidine is also an effective component when managing delirium. Combined analgo-sedation with low doses of short-acting opiates is a preferred sedation strategy to facilitate neurologic exams as well as patient-ventilator synchrony. Optimal care for patients in the neurocritical care population requires an adaptation of general ICU strategies that incorporates understanding of neurophysiology and the need for close neuromonitoring. Recent data continues to improve care tailored to this population.

Propofol-induced in-situ formation of silver nanoparticles: A sensing colorimetric method

A simple and eco-friendly colorimetric sensing method has been developed for the extremely effective detection of propofol in exhaled breath condensate (EBC). In this study, we put forward a Tollens' procedure, in which silver nanoparticles (AgNPs) were produced using propofol as a reducing agent. To verify the in-situ synthesis of AgNPs, the TEM images, and UV-Vis absorbance were recorded in the absence and presence of propofol. The solution turned from a colorless to yellow and deep yellow color due to the surface plasmon resonance absorption band of formed AgNPs. The intensity of nanoparticle absorbance was quantitatively correlated with the propofol concentration. The proposed sensor revealed good linearity over the range of 0.01-0.8 µg mL^-1 at 422 nm with the detection limit of 8.8 ng mL^-1 under optimum conditions. Finally, the proposed colorimetric sensor was successfully used for the determination of propofol in the EBC sample of patients receiving propofol.

Microstate analyses as an indicator of anesthesia-induced unconsciousness

OBJECTIVE

The objective of this study was to identify differences in electroencephalographic microstate topographies across three perioperative phases: anesthetic pre-induction, surgical anesthesia, and post-anesthesia care unit (PACU) admission.

METHODS

Whole-scalp 16-channel electroencephalographic recordings were taken throughout the perioperative period on n = 22 adult, non-cardiac surgical patients.

RESULTS

Several differences between perioperative periods were identified. Most notably, during surgical anesthesia, patients demonstrated increased mean duration and, consequently, a reduction in the occurrence of microstates when compared to both preoperative baseline and PACU admission. We also observed the presence of microstate F with propofol anesthesia during surgery, which had been previously identified with propofol infusion in laboratory settings using human volunteers. Finally, we observed inverse age effects with mean occurrence and duration of microstates, particularly during PACU recovery.

CONCLUSIONS

Microstate duration is significantly increased during surgery compared to both pre-induction and PACU recovery. These data suggest that microstate topographies may be useful in monitoring anesthetic depth.

SIGNIFICANCE

This work highlights the potential for microstate analysis in the perioperative setting. We identified distinct topographical signatures across perioperative periods and with increasing age, which is predictive of post-operative delirium.

Comparing Propofol With Fentanyl and Midazolam for Sedation in Closed Reductions of Traumatic Hip Dislocations

Traumatic native hip dislocations require prompt reduction of the dislocation to limit the risk of avascular necrosis and resultant hip arthrosis. Although closed reduction under sedation is frequently attempted, there is minimal evidence about which sedative agent is most safe and effective. The goal of this study was to compare the efficacy of propofol vs combination fentanyl/midazolam for closed reduction under sedation of traumatic native hip dislocations. This was a single-center retrospective review. The main outcome measures were the rate of successful closed reduction with propofol vs combination fentanyl/midazolam and time from the start of sedation to radiographic evidence of reduction. Fifty-four patients with traumatic native hip dislocations were identified. Closed reduction under sedation with propofol was successful in 11 of 14 attempts compared with 4 of 11 attempts with combination fentanyl/midazolam (P=.04). The fentanyl/midazolam group had 6.4 times the odds (95% CI, 1.1-37.7) of failed closed reduction compared with the propofol group. The median time to reduction in the propofol group was 14 minutes vs 45 minutes for the fentanyl/midazolam group (P=.18). Patients who had failed closed reduction with fentanyl/midazolam had a median time to reduction of 100 minutes. There was no difference in sedation-related complications between the 2 groups. We therefore conclude that sedation with propofol is significantly more effective than combination fentanyl/midazolam for closed reduction of native hip dislocations. To minimize unsuccessful reduction attempts and shorten total time to reduction, we recommend against the use of combination fentanyl/midazolam because of the high risk of failure. [Orthopedics. 2023;46(2):86-92.].

Serratus plane block with sedation for patients submitted to axillary dissection: a prospective case series

Axillary dissection is a standard surgical procedure for stage III skin and soft tissue tumors and is usually performed under general anesthesia. This study aimed to investigate the feasibility of performing axillary dissection with Serratus muscle plane block plus intravenous sedation. Fifteen patients undergoing axillary dissection were prospectively recruited. The patients were evaluated during their pre-operative anesthetic appointment, during their procedure, and at post-operative days 1 and 30. The blockade was performed superficial to the Serratus muscle at the level of fourth rib. Sedation was performed using propofol, fentanyl, dexmedetomidine, and S-ketamine. None of the patients required conversion to general anesthesia. Surgeons showed a highly positive response when asked about the anesthetic technique, and most of them found the technique "indistinguishable" from general anesthesia. The median (interquartile range) pain scores at rest over all time frames was 0 (0-0). Furthermore, no patients developed nausea, hemodynamic instability, or any complications associated with the technique. The Serratus plane block associated with intravenous sedation proved feasible for axillary lymphadenectomy, however, further clinical trials should evaluate potential advantages compared to other techniques.