Desflurane improves electrical activity of neurons and alleviates oxygen-glucose deprivation-induced neuronal injury by activating the Kcna1-dependent Kv1.1 channel.

Several volatile anesthetics have presented neuroprotective functions in ischemic injury. This study investigates the effect of desflurane (Des) on neurons following oxygen-glucose deprivation (OGD) challenge and explores the underpinning mechanism. Mouse neurons HT22 were subjected to OGD, which significantly reduced cell viability, increased lactate dehydrogenase release, and promoted cell apoptosis. In addition, the OGD condition increased oxidative stress in HT22 cells, as manifested by increased ROS and MDA contents, decreased SOD activity and GSH/GSSG ratio, and reduced nuclear protein level of Nrf2. Notably, the oxidative stress and neuronal apoptosis were substantially blocked by Des treatment. Bioinformatics suggested potassium voltage-gated channel subfamily A member 1 (Kcna1) as a target of Des. Indeed, the Kcna1 expression in HT22 cells was decreased by OGD but restored by Des treatment. Artificial knockdown of Kcna1 negated the neuroprotective effects of Des. By upregulating Kcna1, Des activated the Kv1.1 channel, therefore enhancing K+ currents and inducing neuronal repolarization. Pharmacological inhibition of the Kv1.1 channel reversed the protective effects of Des against OGD-induced injury. Collectively, this study demonstrates that Des improves electrical activity of neurons and alleviates OGD-induced neuronal injury by activating the Kcna1-dependent Kv1.1 channel.

Effect of volatile versus propofol anaesthesia on major complications and mortality after cardiac surgery: a multicentre randomised trial.

BACKGROUND: The comparative effectiveness of volatile anaesthesia and total intravenous anaesthesia (TIVA) in terms of patient outcomes after cardiac surgery remains a topic of debate. METHODS: Multicentre randomised trial in 16 tertiary hospitals in China. Adult patients undergoing elective cardiac surgery were randomised in a 1:1 ratio to receive volatile anaesthesia (sevoflurane or desflurane) or propofol-based TIVA. The primary outcome was a composite of predefined major complications during hospitalisation and mortality 30 days after surgery. RESULTS: Of the 3123 randomised patients, 3083 (98.7%; mean age 55 yr; 1419 [46.0%] women) were included in the modified intention-to-treat analysis. The composite primary outcome was met by a similar number of patients in both groups (volatile group: 517 of 1531 (33.8%) patients vs TIVA group: 515 of 1552 (33.2%) patients; relative risk 1.02 [0.92-1.12]; P=0.76; adjusted odds ratio 1.05 [0.90-1.22]; P=0.57). Secondary outcomes including 6-month and 1-yr mortality, duration of mechanical ventilation, length of ICU and hospital stay, and healthcare costs, were also similar for the two groups. CONCLUSIONS: Among adults undergoing cardiac surgery, we found no difference in the clinical effectiveness of volatile anaesthesia and propofol-based TIVA. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trial Registry (ChiCTR-IOR-17013578).

Evaluation of Quality of Recovery With Quality of Recovery-15 Score After Closed-Loop Anesthesia Delivery System-Guided Propofol Versus Desflurane General Anesthesia in Patients Undergoing Transabdominal Robotic Surgery: A Randomized Controlled Study.

BACKGROUND: Robotic technique of surgery allows surgeons to perform complex procedures in difficult-to-access areas of the abdominal/pelvic cavity (eg, radical prostatectomy and radical hysterectomy) with improved access and precision approach. At the same time, automated techniques efficiently deliver propofol total intravenous anesthesia (TIVA) with lower anesthetic consumption. As both above are likely to bring benefit to the patients, it is imperative to explore their effect on postanesthesia recovery. Quality of Recovery-15 (QoR-15) is a comprehensive patient-reported measure of the quality of postanesthesia recovery and assesses compendious patients' experiences (physical and mental well-being). This randomized study assessed the effect of automated propofol TIVA versus inhaled desflurane anesthesia on postoperative quality of recovery using the QoR-15 questionnaire in patients undergoing elective robotic surgery. METHODS: One hundred twenty patients undergoing robotic abdominal surgery under general anesthesia (GA) were randomly allocated to receive propofol TIVA administered by closed-loop anesthesia delivery system (CLADS) (CLADS group) or desflurane GA (desflurane group). Postoperative QoR-15 score on postoperative day 1 (POD-1) and postoperative day 2 (POD-2) (primary outcome variables), individual QoR-15 item scores (15 nos.), intraoperative hemodynamics (heart rate, mean blood pressure), anesthesia depth consistency, anesthesia delivery system performance, early recovery from anesthesia (time-to-eye-opening, and time to tracheal extubation), and postoperative adverse events (sedation, postoperative nausea and vomiting [PONV], pain, intraoperative awareness recall) (secondary outcome variables) were analyzed. RESULTS: On POD-1, the CLADS group scored significantly higher than the desflurane group in terms of "overall" QoR-15 score (QoR-15 score: 114.5 ± 13 vs 102.1 ± 20.4; P = .001) and 3 individual QoR-15 "items" scores ("feeling rested" 7.5 ± 1.9 vs 6.4 ± 2.2, P = .007; "good sleep" 7.8 ± 1.9 vs 6.6 ± 2.7, P = .027; and "feeling comfortable and in control" 8.1 ± 1.7 vs 6.9 ± 2.4, P = .006). On the POD-2, the CLADS group significantly outscored the desflurane group with respect to the "overall" QoR-15 score (126.0 ± 13.6 vs 116.3 ± 20.3; P = .011) and on "5" individual QoR-15 items ("feeling rested" 8.1 ± 1.4 vs 7.0 ± 2.0, P = .003; "able to return to work or usual home activities" 6.0 ± 2.2 vs 4.6 ± 2.6, P = .008; "feeling comfortable and in control" 8.6 ± 1.2 vs 7.7 ± 1.9, P = .004; "feeling of general well-being" 7.8 ± 1.6 vs 6.9 ± 2.0, P = .042; and "severe pain" 9.0 ± 1.9 vs 8.1 ± 2.5, P = .042). CONCLUSIONS: Automated propofol TIVA administered by CLADS is superior to desflurane inhalation GA with respect to early postoperative recovery as comprehensively assessed on the QoR-15 scoring system. The effect of combined automated precision anesthesia and surgery (robotics) techniques on postoperative recovery may be explored further.

Remimazolam to prevent hemodynamic instability during catheter ablation under general anesthesia: a randomized controlled trial.

PURPOSE: Maintaining hemodynamic stability during cardiac ablation under general anesthesia is challenging. Remimazolam, a novel ultrashort-acting benzodiazepine, is characterized by maintaining comparatively stable blood pressure and does not influence the cardiac conduction system, which renders it a reasonable choice for general anesthesia for cardiac ablation. We aimed to evaluate whether remimazolam is associated with a decreased incidence of intraoperative hypotension compared with desflurane. METHODS: In this single-centre, parallel-group, prospective, single-blind, randomized clinical trial, we randomized patients (1:1) into a remimazolam group (remimazolam-based total intravenous anesthesia) or desflurane group (propofol-induced and desflurane-maintained inhalational anesthesia) during cardiac ablation procedures for arrhythmia. The primary outcome was the incidence of intraoperative hypotensive events, defined as mean arterial pressure of < 60 mm Hg at any period. RESULTS: Overall, we enrolled 96 patients between 2 August 2022 and 19 May 2023 (47 and 49 patients in the remimazolam and desflurane groups, respectively). The remimazolam group showed a significantly lower incidence of hypotensive events (14/47, 30%) than the desflurane group (29/49, 59%; relative risk [RR], 0.5; 95% confidence interval [CI], 0.31 to 0.83; P = 0.004). Remimazolam was associated with a lower requirement for bolus or continuous vasopressor infusion than desflurane was (23/47, 49% vs 43/49, 88%; RR, 0.56; 95% CI, 0.41 to 0.76; P < 0.001). No between-group differences existed in the incidence of perioperative complications such as nausea, vomiting, oxygen desaturation, delayed emergence, or pain. CONCLUSIONS: Remimazolam was a viable option for general anesthesia for cardiac ablation. Remimazolam-based total intravenous anesthesia was associated with significantly fewer hypotensive events and vasopressor requirements than desflurane-based inhalational anesthesia was, without significantly more complications. STUDY REGISTRATION: ClinicalTrials.gov (NCT05486377); first submitted 1 August 2022.

RéSUMé: OBJECTIF: Le maintien de la stabilité hémodynamique lors d'une ablation cardiaque sous anesthésie générale est un défi. Le remimazolam, une nouvelle benzodiazépine à action ultra-courte, se caractérise par le maintien d'une tension artérielle relativement stable et son absence d'influence sur le système de conduction cardiaque, ce qui en fait un choix raisonnable pour l'anesthésie générale pour l'ablation cardiaque. Nous avons cherché à déterminer si le remimazolam est associé à une diminution de l'incidence d'hypotension peropératoire comparativement au desflurane. MéTHODE: Dans cette étude clinique randomisée, prospective, en simple aveugle, en groupes parallèles et monocentrique, nous avons randomisé des patient·es (1:1) dans un groupe remimazolam (anesthésie intraveineuse totale à base de remimazolam) et un groupe desflurane (anesthésie volatile induite par propofol et maintenue par desflurane) pendant des interventions d'ablation cardiaque pour arythmie. Le critère d'évaluation principal était l'incidence d'événements hypotensifs peropératoires, définis comme une tension artérielle moyenne de < 60 mm Hg à n'importe quelle période. RéSULTATS: Au total, nous avons recruté 96 patient·es entre le 2 août 2022 et le 19 mai 2023 (47 et 49 personnes dans les groupes remimazolam et desflurane, respectivement). Le groupe remimazolam a montré une incidence significativement plus faible d'événements hypotensifs (14/47, 30 %) que le groupe desflurane (29/49, 59 %; risque relatif [RR], 0,5; intervalle de confiance [IC] à 95 %, 0,31 à 0,83; P = 0,004). Le remimazolam a été associé à des besoins plus faibles de bolus ou de perfusion continue de vasopresseurs que le desflurane (23/47, 49 % vs 43/49, 88 %; RR, 0,56; IC 95 %, 0,41 à 0,76; P < 0,001). Il n'y avait pas de différences entre les groupes dans l'incidence des complications périopératoires telles que les nausées, les vomissements, la désaturation en oxygène, l'émergence retardée ou la douleur. CONCLUSION: Le remimazolam a constitué une option viable pour l'anesthésie générale en vue d'une ablation cardiaque. L'anesthésie intraveineuse totale à base de remimazolam a été associée à un nombre significativement plus faible d'événements d'hypotension et de besoins en vasopresseurs que l'anesthésie par inhalation à base de desflurane, sans complications significativement plus nombreuses. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05486377); soumis pour la première fois le 1er août 2022.

Effects of volatile anesthetics on circadian rhythm in mice: a comparative study of sevoflurane, desflurane, and isoflurane.

PURPOSE: Volatile anesthetics affect the circadian rhythm of mammals, although the effects of different types of anesthetics are unclear. Here, we anesthetized mice using several volatile anesthetics at two different times during the day. Our objective was to compare the effects of these anesthetics on circadian rhythm. METHODS: Male adult C57BL/6 J mice were divided into eight groups (n = 8 each) based on the anesthetic (sevoflurane, desflurane, isoflurane, or no anesthesia) and anesthesia time (Zeitgeber time [ZT] 6-12 or ZT18-24). Mice were anesthetized for 6 h using a 0.5 minimum alveolar concentration (MAC) dose under constant dark conditions. The difference between the start of the active phase before and after anesthesia was measured as a phase shift. Clock genes were measured by polymerase chain reaction in suprachiasmatic nucleus (SCN) samples removed from mouse brain after anesthesia (n = 8-9 each). RESULTS: Phase shift after anesthesia at ZT6-12 using sevoflurane (- 0.49 h) was smaller compared with desflurane (- 1.1 h) and isoflurane (- 1.4 h) (p < 0.05). Clock mRNA (ZT6-12, p < 0.05) and Per2 mRNA (ZT18-24, p < 0.05) expression were different between the groups after anesthesia. CONCLUSION: 0.5 MAC sevoflurane anesthesia administered during the late inactive to early active phase has less impact on the phase shift of circadian rhythm than desflurane and isoflurane. This may be due to differences in the effects of volatile anesthetics on the expression of clock genes in the SCN, the master clock of the circadian rhythm.

Prophylaxis for paediatric emergence delirium in desflurane-based anaesthesia: a network meta-analysis.

PURPOSE: The prevalence of postoperative emergence delirium in paediatric patients (pedED) following desflurane anaesthesia is considerably high at 50-80%. Although several pharmacological prophylactic strategies have been introduced to reduce the risk of pedED, conclusive evidence about the superiority of these individual regimens is lacking. The aim of the current study was to assess the potential prophylactic effect and safety of individual pharmacotherapies in the prevention of pedED following desflurane anaesthesia. METHODS: This frequentist model network meta-analysis (NMA) of randomized controlled trials (RCTs) included peer-reviewed RCTs of either placebo-controlled or active-controlled design in paediatric patients under desflurane anaesthesia. RESULTS: Seven studies comprising 573 participants were included. Overall, the ketamine + propofol administration [odds ratio (OR) = 0.05, 95% confidence intervals (95%CIs) 0.01-0.33], dexmedetomidine alone (OR = 0.13, 95%CIs 0.05-0.31), and propofol administration (OR = 0.30, 95%CIs 0.10-0.91) were associated with a significantly lower incidence of pedED than the placebo/control groups. In addition, only gabapentin and dexmedetomidine were associated with a significantly higher improvement in the severity of emergence delirium than the placebo/control groups. Finally, the ketamine + propofol administration was associated with the lowest incidence of pedED, whereas gabapentin was associated with the lowest severity of pedED among all of the pharmacologic interventions studied. CONCLUSIONS: The current NMA showed that ketamine + propofol administration was associated with the lowest incidence of pedED among all of the pharmacologic interventions studied. Future large-scale trials to more fully elucidate the comparative benefits of different combination regimens are warranted. TRIAL REGISTRATION: PROSPERO CRD42021285200.

The association between intraoperative anesthesia methods used during gastric cancer surgery and long-term mortality: A retrospective observational study using a Japanese claims database.

PURPOSE: Various basic and clinical studies have investigated the association between the types of anesthetic agents and prognosis. However, the results have varied among studies and remain controversial. In the present study, we aimed to investigate whether the risk of all-cause mortality differs between inhaled or intravenous anesthetics in patients with gastric cancer undergoing gastrectomy. METHODS: Using a Japanese nationwide insurance claims database, we analyzed patients who underwent gastrectomy under general anesthesia for gastric cancer between January 2005 and September 2019. Postoperative outcomes were compared between two groups: those who received inhaled anesthetics (Sevoflurane, Isoflurane, or Desflurane) and those who received intravenous anesthetics (propofol), using a multivariable Cox proportional hazards model. The primary outcome was overall survival. RESULTS: Among 2671 eligible patients, 2105 were in the inhaled anesthetic group, and 566 were in the intravenous anesthetic group. The median (interquartile range) age was 58 (51-63) years, and 1979 (74.1%) were men. The median follow-up period was 795 days. We identified 56 (2.7%) and 16 (2.8%) deaths during the follow-up period in the inhaled and intravenous anesthetic use groups, respectively. There was no difference in postoperative overall survival between the two groups (hazard ratio, 0.97; 95% confidence interval, 0.56-1.70; P = 0.93). CONCLUSIONS: We found no significant difference in the postoperative risks of overall survival between inhaled and intravenous anesthesia in patients with gastric cancer undergoing gastrectomy.

Comparison of the Effects of Desflurane and Sevoflurane on Variations in Salivary Melatonin and Sleep Disturbance After Total Knee Arthroplasty: A Single-center, Prospective, Randomized, Controlled, Open-label Study.

PURPOSE: Anesthesia has been shown to disrupt the circadian rhythm. Recovery of the circadian rhythm after general anesthesia might help alleviate symptoms of insomnia and postoperative delirium. We hypothesized that recovery of the circadian rhythm is faster after total knee arthroplasty (TKA) with desflurane than with sevoflurane. This study compared the influence of sevoflurane versus desflurane anesthesia on the postoperative circadian rhythm of melatonin in adults undergoing TKA. DESIGN: Single-center, prospective, randomized, controlled, open-label study. METHODS: This study involved adult patients undergoing TKA at a university hospital in Japan from May 1, 2018 to December 31, 2019. The primary outcome of the study was the comparison of the effect of sevoflurane and desflurane on the circadian rhythm of salivary melatonin for 3 days postoperatively. The secondary outcomes were postoperative fatigue and sleep quality for 3 days postoperatively. FINDINGS: Twenty-eight patients (American Society of Anesthesiologists physical status of I or II) were scheduled for TKA and randomized to receive sevoflurane (n = 14) or desflurane (n = 14) anesthesia. There was no significant difference in the melatonin concentration between the sevoflurane and desflurane groups. The salivary melatonin concentration after sevoflurane or desflurane anesthesia was significantly higher at 9:00 p.m. on a postoperative day (POD)0 and POD1 than on POD3 (P < .05). Patients in the desflurane group had significantly greater fatigue than those in the sevoflurane group at 7:00 a.m. and 12:00 p.m. on POD3 (P < .05). Patients in the sevoflurane group had a deeper sleep than those in the desflurane group on POD0 (P < .05). In the sevoflurane group, the sleep time during the night of POD2 was longer than that on POD0 (6.1 vs 4.2 hours, P < .05). CONCLUSIONS: Under the current study conditions, desflurane was equivalent to sevoflurane in terms of the postoperative salivary melatonin concentration and sleep disturbance after TKA but not in terms of recovering the postoperative circadian rhythm.

Effect of Remimazolam on Pain Perception and Opioid-Induced Hyperalgesia in Patients Undergoing Laparoscopic Urologic Surgery-A Prospective, Randomized, Controlled Study.

Background and Objectives: The effects of midazolam, a benzodiazepine, on pain perception are complex on both spinal and supraspinal levels. It is not yet known whether remimazolam clinically attenuates or worsens pain. The present study investigated the effect of intraoperative remimazolam on opioid-induced hyperalgesia (OIH) in patients undergoing general anesthesia. Materials and Methods: The patients were randomized into three groups: group RHR (6 mg/kg/h initial dose followed by 1 mg/kg/h remimazolam and 0.3 µg /kg/min remifentanil), group DHR (desflurane and 0.3 µg /kg/min remifentanil) or group DLR (desflurane and 0.05 µg/kg /min remifentanil). The primary outcome was a mechanical hyperalgesia threshold, while secondary outcomes included an area of hyperalgesia and clinically relevant pain outcomes. Results: Group RHR had a higher mechanical hyperalgesia threshold, a smaller hyperalgesia postoperative area at 24 h, a longer time to first rescue analgesia (p = 0.04), lower cumulative PCA volume containing morphine postoperatively consumed for 24 h (p < 0.01), and lower pain intensity for 12 h than group DHR (p < 0.001). However, there was no significant difference in OIH between groups RHR and DLR. Conclusions: Group RHR, which received remimazolam, attenuated OIH, including mechanically evoked pain and some clinically relevant pain outcomes caused by a high dose of remifentanil. Further research is essential to determine how clinically meaningful and important the small differences observed between the two groups are.

Myocardial Protection by Desflurane: From Basic Mechanisms to Clinical Applications.

ABSTRACT: Coronary heart disease is an affliction that is common and has an adverse effect on patients' quality of life and survival while also raising the risk of intraoperative anesthesia. Mitochondria are the organelles most closely associated with the pathogenesis, development, and prognosis of coronary heart disease. Ion abnormalities, an acidic environment, the production of reactive oxygen species, and other changes during abnormal myocardial metabolism cause the opening of mitochondrial permeability transition pores, which disrupts electron transport, impairs mitochondrial function, and even causes cell death. Differences in reliability and cost-effectiveness between desflurane and other volatile anesthetics are minor, but desflurane has shown better myocardial protective benefits in the surgical management of patients with coronary artery disease. The results of myocardial protection by desflurane are briefly summarized in this review, and biological functions of the mitochondrial permeability transition pore, mitochondrial electron transport chain, reactive oxygen species, adenosine triphosphate-dependent potassium channels, G protein-coupled receptors, and protein kinase C are discussed in relation to the protective mechanism of desflurane. This article also discusses the effects of desflurane on patient hemodynamics, myocardial function, and postoperative parameters during coronary artery bypass grafting. Although there are limited and insufficient clinical investigations, they do highlight the possible advantages of desflurane and offer additional suggestions for patients.

Association Between Anesthesia Provider Education and Carbon Footprint Related to the Use of Inhaled Halogenated Anesthetics.

BACKGROUND: Inhaled halogenated anesthetics are responsible for half of operating room total greenhouse gas emissions. Sustainable anesthesia groups were set up in 4 Lyon, France, university hospitals (Hospices Civils de Lyon) in January 2018 and have supported a specific information campaign about the carbon footprint related to the use of inhaled halogenated anesthetics in June 2019. We aimed to assess whether implementing such information campaigns was associated with a decrease in the carbon footprint related to inhaled halogenated anesthetics. METHODS: This retrospective cohort study was conducted from January 1, 2015, to February 29, 2020, in 4 hospitals of the Hospices Civils de Lyon in France. Information meetings on sustainable anesthesia practices were organized by sustainable anesthesia groups that were set up in January 2018. In addition, a specific information campaign about the carbon footprint related to inhaled halogenated anesthetics was conducted in June 2019; it was followed by a questionnaire to be completed online. The monthly purchase of sevoflurane, desflurane, and propofol was recorded, and the estimated monthly carbon footprint from desflurane- and sevoflurane-related perioperative emissions was calculated. The interrupted time-series data from January 2015 to February 2020 were analyzed by segmented regression, considering both interventions (setting up of the sustainable anesthesia groups and specific information campaign) in the analysis and adjusting for 2 confounding factors (seasonality of the data and number of general anesthesia uses). RESULTS: Among the 641 anesthesia providers from the study hospitals, 121 (19%) attended the information meetings about the carbon footprint of inhaled halogenated anesthetics, and 180 (28%) completed the questionnaire. The anesthetic activity from all 641 providers was considered in the analysis. After the sustainable anesthesia groups were set up, the carbon footprint of sevoflurane and desflurane started decreasing: the slope significantly changed ( P < .01) and became significantly negative, from -0.27 (95% confidence interval [CI], -1.08 to 0.54) tons.month -1 to -14.16 (95% CI, -16.67 to -11.65) tons.month -1 . After the specific information campaign, the carbon footprint kept decreasing, with a slope of -7.58 (95% CI, -13.74 to -1.41) tons.month -1 ( P = .02), which was not significantly different from the previous period ( P = .07). CONCLUSIONS: The setup of the sustainable anesthesia groups was associated with a dramatic reduction in the carbon footprint related to halogenated anesthetics. These results should encourage health care institutions to undertake information campaigns toward anesthesia providers so that they also take into account the environmental impact in the choice of anesthetic drugs, in addition to the benefits for the patient and economic concerns.

Project SPRUCE: Saving Our Planet by Reducing Carbon Emissions, a Pediatric Anesthesia Sustainability Quality Improvement Initiative.

BACKGROUND: Children are particularly vulnerable to adverse health outcomes related to climate change. Inhalational anesthetics are potent greenhouse gasses (GHGs) and contribute significantly to health care-generated emissions. Desflurane and nitrous oxide have very high global warming potentials. Eliminating their use, as well as lowering fresh gas flows (FGFs), will lead to reduced emissions. METHODS: Using published calculations for converting volatile anesthetic concentrations to carbon dioxide equivalents (CO 2 e), we derived the average kilograms (kg) CO 2 e/min for every anesthetic administered in the operating rooms at our pediatric hospital and ambulatory surgical center between October 2017 and October 2022. We leveraged real-world data captured from our electronic medical record systems and used AdaptX to extract and present those data as statistical process control (SPC) charts. We implemented recommended strategies aimed at reducing emissions from inhalational anesthetics, including removing desflurane vaporizers, unplugging nitrous oxide hoses, decreasing the default anesthesia machine FGF, clinical decision support tools, and educational initiatives. Our primary outcome measure was average kg CO 2 e/min. RESULTS: A combination of educational initiatives, practice constraints, protocol changes, and access to real-world data were associated with an 87% reduction in measured GHG emissions from inhaled anesthesia agents used in the operating rooms over a 5-year period. Shorter cases (<30 minutes duration) had 3 times higher average CO 2 e, likely due to higher FGF and nitrous oxide use associated with inhalational inductions, and higher proportion of mask-only anesthetics. Removing desflurane vaporizers corresponded with a >50% reduction of CO 2 e. A subsequent decrease in anesthesia machine default FGF was associated with a similarly robust emissions reduction. Another significant decrease in emissions was noted with educational efforts, clinical decision support alerts, and feedback from real-time data. CONCLUSIONS: Providing environmentally responsible anesthesia in a pediatric setting is a challenging but achievable goal, and it is imperative to help mitigate the impact of climate change. Large systems changes, such as eliminating desflurane, limiting access to nitrous oxide, and changing default anesthesia machine FGF rates, were associated with rapid and lasting emissions reduction. Measuring and reporting GHG emissions from volatile anesthetics allows practitioners to explore and implement methods of decreasing the environmental impact of their individual anesthesia delivery practices.

Reducing Volatile Anesthetic Waste Using a Commercial Electronic Health Record Clinical Decision Support Tool to Lower Fresh Gas Flows.

BACKGROUND: Volatile anesthetic consumption can be reduced by minimizing excessive fresh gas flows (FGFs). Currently, it is unknown whether decision support tools embedded within commercial electronic health record systems can be successfully adopted to achieve long-term reductions in FGF rates. The authors describe the implementation of an electronic health record-based clinical decision support tool aimed at reducing FGF and evaluate the effectiveness of this intervention in achieving sustained reductions in FGF rates and volatile anesthetic consumption. METHODS: On August 29, 2018, we implemented a decision support tool within the Epic Anesthesia Information Management System (AIMS) to alert providers of high FGF (>0.7 L/min for desflurane and >1 L/min for sevoflurane) during maintenance of anesthesia. July 22, 2015, to July 10, 2018, served as our baseline period before the intervention. The intervention period spanned from August 29, 2018, to December 31, 2019. Our primary outcomes were mean FGF (L/min) and volatile agent consumption (mL/MAC-h). Because a simple comparison of 2 time periods may result in false conclusions due to underlying trends independent of the intervention, we performed segmented regression of the interrupted time series to assess the change in level at the start of the intervention and the differences in slopes before and after the intervention. The analysis was also adjusted for potential confounding variables. Data included 44,899 cases using sevoflurane preintervention with 26,911 cases postintervention, and 17,472 cases using desflurane with 1185 cases postintervention. RESULTS: Segmented regression of the interrupted times series demonstrated a decrease in mean FGF by 0.6 L/min (95% CI, 0.6-0.6 L/min; P < .0001) for sevoflurane and 0.2 L/min (95% CI, 0.2-0.3 L/min; P < .0001) for desflurane immediately after implementation of the intervention. For sevoflurane, mL/MAC-h decreased by 3.8 mL/MAC-h (95% CI, 3.6-4.1 mL/MAC-h; P < .0001) after implementation of the intervention and decreased by 4.1 mL/MAC-h (95% CI, 2.6-5.6 mL/MAC-h; P < .0001) for desflurane. Slopes for both FGF and mL/MAC-h in the postintervention period were statistically less negative than the preintervention slopes (P < .0001 for sevoflurane and P < .01 for desflurane). CONCLUSIONS: A commercial AIMS-based decision support tool can be adopted to change provider FGF management patterns and reduce volatile anesthetic consumption in a sustainable fashion.

Anesthetic Management and Deep Sedation After Emergence From General Anesthesia: A Retrospective Cohort Study.

BACKGROUND: Residual deep sedation during anesthesia recovery may predict postoperative complications. We examined the incidence and risk factors for deep sedation after general anesthesia. METHODS: We retrospectively reviewed health records of adults who underwent procedures with general anesthesia and were admitted to the postanesthesia care unit from May 2018 to December 2020. Patients were dichotomized by Richmond Agitation-Sedation Scale (RASS) score: ≤-4 (deeply sedated/unarousable) or ≥-3 (not deeply sedated). Anesthesia risk factors for deep sedation were assessed with multivariable logistic regression. RESULTS: Of the 56,275 patients included, 2003 had a RASS ≤-4 (35.6 [95% CI, 34.1-37.2] cases per 1000 anesthetics administered). On adjusted analyses, the likelihood of a RASS ≤-4 increased when more soluble halogenated anesthetics were used. Compared with desflurane without propofol, the odds ratio (OR [95% CI]) for a RASS ≤-4 was higher with sevoflurane (1.85 [1.45-2.37]) and isoflurane (4.21 [3.29-5.38]) without propofol. Compared with desflurane without propofol, the odds of a RASS ≤-4 further increased with use of desflurane-propofol (2.61 [1.99-3.42]), sevoflurane-propofol (4.20 [3.28-5.39]), isoflurane-propofol (6.39 [4.90-8.34]), and total intravenous anesthesia (2.98 [2.22-3.98]). A RASS ≤-4 was also more likely with the use of dexmedetomidine (2.47 [2.10-2.89]), gabapentinoids (2.17 [1.90-2.48]), and midazolam (1.34 [1.21-1.49]). Deeply sedated patients discharged to general care wards had higher odds of opioid-induced respiratory complications (2.59 [1.32-5.10]) and higher odds of naloxone administration (2.93 [1.42-6.03]). CONCLUSIONS: Likelihood of deep sedation after recovery increased with intraoperative use of halogenated agents with higher solubility and increased further when propofol was concomitantly used. Patients who experience deep sedation during anesthesia recovery have an increased risk of opioid-induced respiratory complications on general care wards. These findings may be useful for tailoring anesthetic management to reduce postoperative oversedation.

A call for immediate climate action in anesthesiology: routine use of minimal or metabolic fresh gas flow reduces our ecological footprint.

PURPOSE: Climate change is a global threat, and inhalational anesthetics contribute to global warming by altering the photophysical properties of the atmosphere. On a global perspective, there is a fundamental need to reduce perioperative morbidity and mortality and to provide safe anesthesia. Thus, inhalational anesthetics will remain a significant source of emissions in the foreseeable future. It is, therefore, necessary to develop and implement strategies to minimize the consumption of inhalational anesthetics to reduce the ecological footprint of inhalational anesthesia. SOURCE: We have integrated recent findings concerning climate change, characteristics of established inhalational anesthetics, complex simulative calculations, and clinical expertise to propose a practical and safe strategy to practice ecologically responsible anesthesia using inhalational anesthetics. PRINCIPAL FINDINGS: Comparing the global warming potential of inhalational anesthetics, desflurane is about 20 times more potent than sevoflurane and five times more potent than isoflurane. Balanced anesthesia using low or minimal fresh gas flow (≤ 1 L·min-1) during the wash-in period and metabolic fresh gas flow (0.35 L·min-1) during steady-state maintenance reduces CO2 emissions and costs by approximately 50%. Total intravenous anesthesia and locoregional anesthesia represent further options for lowering greenhouse gas emissions. CONCLUSION: Responsible anesthetic management choices should prioritize patient safety and consider all available options. If inhalational anesthesia is chosen, the use of minimal or metabolic fresh gas flow reduces the consumption of inhalational anesthetics significantly. Nitrous oxide should be avoided entirely as it contributes to depletion of the ozone layer, and desflurane should only be used in justified exceptional cases.

RéSUMé: OBJECTIF: Les changements climatiques constituent une menace mondiale et les anesthésiques volatils contribuent au réchauffement climatique en modifiant les propriétés photophysiques de l'atmosphère. Dans une perspective mondiale, il est fondamentalement nécessaire de réduire la morbidité et la mortalité périopératoires et de procurer une anesthésie sécuritaire. Par conséquent, les agents volatils demeureront une source importante d'émissions dans un avenir proche. Il est donc nécessaire d'élaborer et de mettre en œuvre des stratégies pour minimiser la consommation d'anesthésiques volatils afin de réduire l'empreinte écologique de l'anesthésie par inhalation. SOURCES: Nous avons intégré les découvertes récentes concernant les changements climatiques, les caractéristiques des anesthésiques volatils connus, des calculs de simulation complexes et l'expertise clinique pour proposer une stratégie pratique et sécuritaire pour exercer une anesthésie écologiquement responsable en utilisant des anesthésiques volatils. CONSTATATIONS PRINCIPALES: En comparant le potentiel de réchauffement planétaire des anesthésiques volatils, le desflurane est environ 20 fois plus puissant que le sévoflurane et cinq fois plus puissant que l'isoflurane. Une anesthésie équilibrée avec un débit de gaz frais faible ou minimal (≤ 1 L·min-1) pendant la période de mise en route ('wash-in') et le débit métabolique de gaz frais (0,35 L·min-1) pendant le maintien à l'état d'équilibre réduit le CO2 et les coûts d'environ 50 %. L'anesthésie intraveineuse totale et l'anesthésie locorégionale représentent d'autres options pour réduire les émissions de gaz à effet de serre. CONCLUSION: Les choix responsables en matière de prise en charge anesthésique devraient accorder la priorité à la sécurité des patients et à l'évaluation de toutes les options disponibles. Si l'anesthésie par inhalation est choisie, l'utilisation d'un débit minimal ou métabolique de gaz frais réduit considérablement la consommation d'anesthésiques volatils. Le protoxyde d'azote doit être complètement évité car il contribue à l'appauvrissement de la couche d'ozone, et le desflurane ne doit être utilisé que dans les cas exceptionnels et justifiés.

Effects of dexmedetomidine on evoked potentials in spinal surgery under combined intravenous inhalation anesthesia: a randomized controlled trial.

OBJECTIVE: We aimed to investigate the effects of different doses of dexmedetomidine (Dex) on evoked potentials in adult patients undergoing spinal surgery under intravenous anesthesia with low-concentration desflurane. METHODS: Ninety patients were divided into three groups at random. To maintain anesthesia in the control group (group C), desflurane 0.3 MAC (minimal alveolar concentration), propofol, and remifentanil were administered. Dex (0.5 µg·kg-1) was injected for 10 min as a loading dose in the low-dose Dex group (group DL), then adjusted to 0.2 µg·kg-1·h-1 until the operation was completed. Dex (1 µg·kg-1) was injected for 10 min as a loading dose in the high-dose Dex group (group DH), then adjusted to 0.7 µg·kg-1·h-1 until the operation was completed. The additional medications were similar to those given to group C. The perioperative hemodynamics, body temperature, intraoperative drug dosages, fluid volume, urine volume, blood loss, the latency and amplitude of somatosensory evoked potentials (SEPs) at four different time points, the incidence of positive cases of SEPs and transcranial motor evoked potentials (tcMEPs), and perioperative adverse reactions were all recorded. RESULTS: Data from 79 patients were analyzed. The MAP measured at points T2-T4 in group DH was higher than at corresponding points in group C (P < 0.05). The MAP at point T4 in group DL was higher than at corresponding points in group C (P < 0.05). The remifentanil dosage in group DH was significantly lower than in group C (P = 0.015). The fluid volume in group DL was significantly lower than in group C (P = 0.009). There were no significant differences among the three groups in the amplitude and latency of SEP at different time points, nor in the incidence of warning SEP signals. The incidence of positive tcMEP signals did not differ significantly between groups C and DL (P > 0.05), but was significantly higher in group DH than in groups DL (P < 0.05) or C (P < 0.05). The incidence of intraoperative hypertension was significantly higher in group DH than in group C (P = 0.017). CONCLUSIONS: Low-dose Dex has no effect on the SEPs and tcMEPs monitoring during spinal surgery. High-dose Dex has no effect on SEPs monitoring, but it may increase the rate of false positive tcMEPs signals and the incidence of intraoperative hypertension. TRIAL REGISTRATION: This study has completed the registration of the Chinese Clinical Trial Center at 11/09/2020 with the registration number ChiCTR2000038154.

Effects of remimazolam on hemodynamic changes during cardiac ablation for atrial fibrillation under general anesthesia: a propensity-score-matched retrospective cohort study.

PURPOSE: Abrupt hemodynamic changes or life-threatening arrhythmias are frequently observed in individuals receiving anesthesia for cardiac arrhythmia ablation. Remimazolam is a novel ultra-short-acting benzodiazepine that has been associated with better hemodynamic stability than conventional anesthetic agents do. This study aimed to investigate whether remimazolam reduces vasoactive agent use compared with desflurane in individuals undergoing ablation for atrial fibrillation under general anesthesia. METHODS: In a retrospective cohort study, we reviewed electronic medical records of adult patients who underwent ablation for atrial fibrillation under general anesthesia between July 2021 and July 2022. We divided patients into remimazolam and desflurane groups according to the principal agent used for anesthesia. The primary endpoint was the overall incidence of vasoactive agent use. We compared the groups using propensity-score matching (PSM) analysis. RESULTS: A total of 177 patients were included-78 in the remimazolam group and 99 in the desflurane group. After PSM, 78 final patients were included in each group. The overall incidence of vasoactive agent use was significantly lower in the remimazolam group than in the desflurane group (41% vs 74% before PSM; 41% vs 73% after PSM; both, P < 0.001). The incidence rate, duration, and maximum dose of continuous vasopressor infusion were also significantly lower in the remimazolam group (P < 0.001). Use of remimazolam was not associated with increased complications after the ablation procedures. CONCLUSIONS: General anesthesia using remimazolam vs desflurane was associated with significantly reduced vasoactive agent requirement and better hemodynamic stability without increased postoperative complications in patients undergoing ablation for atrial fibrillation.

RéSUMé: OBJECTIF: Des changements hémodynamiques brusques ou des arythmies potentiellement mortelles sont fréquemment observés chez les personnes recevant une anesthésie pour une ablation d'arythmie cardiaque. Le remimazolam est une nouvelle benzodiazépine à action ultra-courte qui a été associé à une meilleure stabilité hémodynamique que les agents anesthésiques conventionnels. Cette étude visait à déterminer si le remimazolam réduit l'utilisation d'agents vasoactifs par rapport au desflurane chez les personnes bénéficiant d'une ablation pour fibrillation auriculaire sous anesthésie générale. MéTHODE: Dans une étude de cohorte rétrospective, nous avons examiné les dossiers médicaux électroniques de patient·es adultes ayant bénéficié d'une ablation pour fibrillation auriculaire sous anesthésie générale entre juillet 2021 et juillet 2022. Nous avons divisé les patient·es en groupes de remimazolam et de desflurane en fonction de l'agent principal utilisé pour l'anesthésie. Le critère d'évaluation principal était l'incidence globale de l'utilisation d'agents vasoactifs. Nous avons comparé les groupes à l'aide d'une analyse d'appariement par score de propension (ASP). RéSULTATS: Au total, 177 patient·es ont été inclus·es, dont 78 dans le groupe remimazolam et 99 dans le groupe desflurane. Après l'ASP, 78 patient·es ont été inclus·es au final dans chaque groupe. L'incidence globale d'utilisation d'agents vasoactifs était significativement plus faible dans le groupe remimazolam que dans le groupe desflurane (41 % vs 74 % avant l'ASP; 41 % vs 73 % après l'ASP; les deux P < 0,001). Le taux d'incidence, la durée et la dose maximale de perfusion continue de vasopresseurs étaient également significativement plus faibles dans le groupe remimazolam (P < 0,001). L'utilisation de remimazolam n'a pas été associée à une augmentation des complications après les interventions d'ablation. CONCLUSION: L'anesthésie générale à base de remimazolam vs desflurane a été associée à une réduction significative des besoins en agents vasoactifs et à une meilleure stabilité hémodynamique sans augmentation des complications postopératoires chez les patient·es bénéficiant d'une ablation pour fibrillation auriculaire.

Effects of cerium oxide (CeO2) on liver tissue in liver ischemia-reperfusion injury in rats undergoing desflurane anesthesia.

INTRODUCTION: During liver surgery and transplantation, periods of partial or total vascular occlusion are inevitable and result in ischemia-reperfusion injury (IRI). Nanomedicine uses the latest technology, which has emerged with interdisciplinary effects, such as biomedical sciences, physics, and engineering, to protect and improve human health. Interdisciplinary research has brought along the introduction of antioxidant nanoparticles as potential therapeutics. The goal of this study was to investigate the effects of cerium oxide (CeO2) administration and desflurane anesthesia on liver tissue in liver IR injury. MATERIAL AND METHODS: Thirty rats were randomly divided into five groups: control (C), ischemia-reperfusion (IR), IR-desflurane (IRD), cerium oxide-ischemia reperfusion (CeO2-IR), and cerium oxide-ischemia reperfusion-desflurane (CeO2-IRD). In the IR, IRD, and CeO2-IRD groups, hepatic ischemia was induced after the porta hepatis was clamped for 120 min, followed by 120 min of reperfusion. Intraperitoneal 0.5 mg/kg CeO2 was administered to the CeO2 groups 30 min before ischemia. Desflurane (6%) was administered to the IRD and CeO2-IRD groups during IR. All groups were sacrificed under anesthesia. Liver tissue samples were examined under a light microscope by staining with hematoxylin-eosin (H&E). Malondialdehyde (MDA) levels, catalase (CAT), glutathione-s-transferase (GST), and arylesterase (ARE) enzyme activities were measured in the tissue samples. RESULTS: The IR group had considerably more hydropic degeneration, sinusoidal dilatation, and parenchymal mononuclear cell infiltration than the IRD, CeO2-IR, and CeO2-IRD groups. Catalase and GST enzyme activity were significantly higher in the CeO2-IR group than in the IR group. The MDA levels were found to be significantly lower in the IRD, CeO2-IR, and CeO2-IRD groups than in the IR group. CONCLUSION: Intraperitoneal CeO2 with desflurane reduced oxidative stress and corrected liver damage.

Hemodynamic responses to 1 MAC desflurane inhalation during anesthesia induction with propofol bolus and remifentanil continuous infusion: a prospective randomized single-blind clinical investigation.

BACKGROUND: Desflurane is not recommended during anesthesia induction because of its sympathetic stimulation effect, particularly in patients with myocardial ischemic disease. To date, the hemodynamic response to 1 MAC desflurane inhalation in combination with remifentanil infusion during anesthesia induction has rarely been reported. METHODS: This investigation was designed to compare hemodynamic responses to 1 MAC desflurane (group D, n = 200) with sevoflurane (group S, n = 200) during anesthesia induction and endotracheal intubation in adult patients undergoing elective spine surgery. Subgroup analysis of the different age subgroups was also performed. With continuous infusion of remifentanil 0.1 µg/kg/min, anesthesia was induced with propofol bolus, and endotracheal intubation was performed after muscle relaxation. Heart rate (HR) and mean arterial blood pressure (MAP) were measured every minute for 5 min after anesthesia induction (T1-5) and after endotracheal intubation (T6-10). RESULTS: HR was significantly higher in group D (n = 182) than in group S (n = 173) at T3-10 except at T6 (1 min after intubation) (all P < 0.05). In the age-based subgroup analyses, which subdivided the group D and S into four subgroups based on patient's age, the changes in HR from baseline values were significantly different between the coeval subgroups of patients in their 20-29 years and 30-39 years of age (all P < 0.05). MAP was reduced from baseline value, irrespective of group and age. CONCLUSION: Inhalation of 1 MAC desflurane during anesthesia induction with propofol bolus and remifentanil continuous infusion and during endotracheal intubation was more likely to induce elevations in HR more likely than 1 MAC sevoflurane, especially in younger patients. TRIAL REGISTRATION: This study was registered in the Clinical Research Information Service (CRIS, http://cris.nih.go.kr ) of the Republic of Korea on Feb 12, 2016 (Registration No. KCT 0,001,813).

Efficacy of a propofol bolus against placebo to prevent cough at emergence from general anesthesia with desflurane: a randomized controlled trial.

PURPOSE: Emergence from anesthesia is a critical period and cough can result in adverse effects. Propofol inhibits airway reflexes and when infused it reduces cough more than inhalation anesthesia does. We evaluated the effect of a propofol bolus given at emergence on the incidence of coughing following a desflurane-based anesthesia. METHODS: One hundred and fifty-four patients scheduled for elective surgery were prospectively randomized to propofol (0.5 mg·kg-1) or normal saline (NS) administered at the end of the surgery at 1 minimum alveolar concentration (MAC) of desflurane. A "no touch" emergence technique was used until extubation. The primary outcome was the incidence of cough at the discontinuation of desflurane (T0) and reaching a MAC adjusted for age (MACage) of 0.15. Secondary outcomes included incidence and severity of cough until five minutes postextubation (T0-T5), time to extubation, nausea and vomiting, sedation, hemodynamic variations, postoperative hypoventilation, hypoxemia, and sore throat. RESULTS: We could not draw inferences on the incidence of cough between T0 and MACage of 0.15 because only 27/68 (40%) patients in the NS group and 13/73 (18%) patients in the propofol group regained consciousness before reaching a MACage of 0.15. There were no significant differences between the groups in coughing incidence and severity between T0 and T5 (NS group, 57/68 [84%] vs propofol group, 70/73 [96%] ). The mean time to extubation in the propofol group was prolonged by 3 min 27 sec (95% confidence interval, 1 min 7 sec to 4 min 47 sec; P < 0.001) and more vasopressors were used at emergence (P = 0.02). The incidence of respiratory complications, nausea and vomiting, agitation, and sedation were not different between groups. CONCLUSION: In the present trial, a propofol bolus administered at emergence did not reduce the incidence of cough occurring between T0 and T5 following a desflurane-based general anesthesia compared with placebo. TRIAL REGISTRATION: ClinicalTrials.gov (NCT02932397); registered 13 October 2016.

RéSUMé: OBJECTIF: L'émergence de l'anesthésie est une période critique et la toux peut entraîner des effets indésirables. Le propofol inhibe les réflexes des voies aériennes et, lorsqu'il est perfusé, il est plus efficace pour réduire la toux que l'anesthésie inhalée. Nous avons évalué l'effet d'un bolus de propofol administré à l'émergence sur l'incidence de toux après une anesthésie à base de desflurane. MéTHODE: Cent cinquante-quatre patients devant bénéficier d'une chirurgie non urgente ont été randomisés prospectivement à recevoir du propofol (0,5 mg·kg−1) ou une solution physiologique de sérum salé (NS) administrée à la fin de la chirurgie lorsque la concentration alvéolaire minimale (MAC) de desflurane était de 1. Une technique d'émergence « sans contact ¼ a été utilisée jusqu'à l'extubation. Le critère d'évaluation principal était l'incidence de toux à l'arrêt du desflurane (T0) et à l'atteinte d'une MAC ajustée en fonction de l'âge (MACâge) de 0,15. Les critères d'évaluation secondaires comprenaient l'incidence et la gravité de la toux jusqu'à cinq minutes après l'extubation (T0-T5), le délai d'extubation, les nausées et vomissements, la sédation, les variations hémodynamiques, l'hypoventilation postopératoire, l'hypoxémie et les maux de gorge. RéSULTATS: Nous n'avons pas pu tirer de conclusions sur l'incidence de toux entre T0 et à une MACâge de 0,15 parce que seulement 27/68 (40 %) patients du groupe NS et 13/73 (18 %) patients du groupe propofol ont repris conscience avant d'atteindre une MACâge de 0,15. Il n'y avait aucune différence significative entre les groupes dans l'incidence et la gravité de la toux entre T0 et T5 (groupe NS, 57/68 [84 %] vs groupe propofol, 70/73 [96 %]). Le temps moyen d'extubation dans le groupe propofol a été prolongé de 3 min 27 sec (intervalle de confiance à 95 %, 1 min 7 sec à 4 min 47 sec; P < 0,001) et une plus grande quantité de vasopresseurs a été utilisée à l'émergence (P = 0,02). L'incidence de complications respiratoires, de nausées et vomissements, d'agitation, et de sédation n'était pas différente entre les groupes. CONCLUSION: Dans la présente étude, un bolus de propofol administré à l'émergence n'a pas réduit l'incidence de toux survenant entre T0 et T5 après une anesthésie générale à base de desflurane par rapport au placebo. ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT02932397); enregistrée le 13 octobre 2016.