Intravenous Anesthesia Research Articles

Incidences of Rocuronium Use during Anesthetic Induction in Adult Patients Undergoing Orthopedic Surgery Using Supraglottic Airway Devices: A Retrospective Analysis.

Background/Objectives: Neuromuscular blocking agents (NMBAs) are not usually necessary during the induction of general anesthesia in patients using supraglottic airway (SGA) devices. In this study, we assessed the incidences of rocuronium use in adult patients undergoing general anesthesia using SGA devices. Methods: From September 2022 to August 2023, the medical records of adult patients (≥19 years) who underwent orthopedic surgery using SGA devices were retrospectively investigated. The incidences of rocuronium use during anesthetic induction were analyzed according to the anesthetic induction drug. The association of rocuronium use during anesthesia was analyzed in terms of demographic (age, sex, height, and weight), surgical (surgical time), and anesthetic factors (premedication, anesthetic agent, anesthetic time). Results: In total, 321 patients were enrolled. The incidence rate of rocuronium use during anesthetic induction was 28.3%. In the subgroup analysis, patients receiving total intravenous anesthesia (TIVA) with propofol (PPF) and remifentanil showed a markedly lower incidence (14.4%) than the other anesthetic groups. Premedication or short anesthetic duration was associated with lower incidences of rocuronium use. Demographic and other anesthetic factors did not seem to affect the incidences of rocuronium use during anesthesia. Conclusions: The incidence of rocuronium use during anesthetic induction with SGA devices was significantly lower with the PPF-TIVA compared to that using remimazolam-TIVA or inhalational anesthesia. Premedication with midazolam and shorter operation times were associated with a significantly lower incidence of rocuronium use.

Recommendation for the practice of total intravenous anesthesia.

This Recommendation was developed by the Japanese Society of Intravenous Anesthesia Recommendation Making Working Group (JSIVA-WG) to promote the safe and effective practice of total intravenous anesthesia (TIVA), tailored to the current situation in Japan. It presents a policy validated by the members of JSIVA-WG and a review committee for practical anesthesia management. Anesthesiologists should acquire and maintain the necessary knowledge and skills to be able to administer TIVA properly. A secure venous access is critically important for TIVA. To visualize and understand the pharmacokinetics of intravenous anesthetics, use of real-time pharmacokinetic simulations is strongly recommended. Syringe pumps are essential for the infusion of intravenous anesthetics, which should be prepared according to the rules of each individual anesthesia department, particularly with regard to dilution. Syringes should be clearly labeled with content and drug concentration. Whenmanaging TIVA, particularly with the use of muscle relaxants, monitoring processed electroencephalogram (EEG) is advisable. However, the depth of sedation/anesthesia must be assessed comprehensively using various parameters, rather than simply relying on a single EEG index. TIVA should be swiftly changed to an alternative method that includes inhalation anesthesia if necessary. Use of antagonists at emergence may be associated with re-sedation risk. Casual administration of antagonists and sending patients back to surgical wards without careful observation are not acceptable.

Intravenous anesthetics have differential effects on human potassium channels

Intravenous anesthetics have differential effects on human potassium channels

Anaesthesia and climate change: time to wake up? A rapid qualitative appraisal exploring the views of anaesthetic practitioners regarding the transition to TIVA and the reduction of desflurane

BackgroundThe National Health Service (NHS) has pledged to reach carbon net-zero by 2040. In alignment with this goal, a London hospital’s anaesthesia department is actively reducing desflurane use and transitioning towards total intravenous anaesthesia (TIVA) as a sustainable alternative, contributing to environmentally responsible practices within the healthcare sector.MethodsWe conducted a rapid qualitative appraisal through online interviews with 17 anaesthetic practitioners to explore their perspectives regarding this climate change mitigation strategy. Data analysis was undertaken through the use of rapid appraisal sheets and a framework analysis method.ResultsParticipants highlighted the disadvantages of TIVA, including the increased effort, heightened monitoring requirements, operational challenges, and a lack of clinical confidence associated with its use. Despite these reservations, participants acknowledged TIVA’s potential to reduce postoperative nausea. There were perceptions that senior staff members might resist this change due to habits and scepticism over its impact on climate change. To facilitate greater TIVA adoption, participants recommended enhanced training, the implementation of a dashboard to raise awareness of greenhouse gas (GHG) emissions, and the presence of strong climate change leadership within the department. Participants believed that a shift to TIVA should be followed by specific measures such as addressing waste management which is crucial for GHG reduction, emphasising the perceived link between waste and emissions.ConclusionsThe evaluation examines stakeholder attitudes, perceptions, and behaviours, focusing on transitioning from desflurane to TIVA. The study highlights the importance of staff engagement, organisational support, and underscores the crucial role that healthcare practitioners and leadership play in fostering sustainability within the healthcare sector.

Promoting behavioural change by educating anaesthetists about the environmental impact of inhalational anaesthetic agents: A systematic review.

Of the total carbon footprint of Australia, 7% is attributed to healthcare. In the UK, inhalational agents make up 5% of the healthcare carbon footprint. This systematic review aims to determine which methods of education about the environmental impact of inhalational anaesthetic agents can be utilised to promote behaviour change, reducing the anaesthetic-related carbon footprint. This systematic review sourced records from CINAHL, EMBASE, ERIC, JBI and MEDLINE from 1970 to March 2022. The search identified 589 records, 13 of which met eligibility criteria after the screening process, in which 10 of these records were conference abstracts. Education curricula focused on inhalational agent choice (69%), lowering the fresh gas flow during maintenance anaesthesia (69%), encouraging alternatives such as total intravenous anaesthesia (23%) and/or switching off the gas on transfer (8%). The most common teaching techniques utilised in education curricula were didactic lectures (85%), visual prompts (54%), emails (46%), and conversation forums (31%). All but one study reported a positive relationship between teaching sessions and behavioural change resulting in lower inhalational anaesthetic use by participants and their organisations, reducing healthcare-associated emissions. This systematic review has demonstrated that single education sessions as well as multi-focused, multimodal education curricula on the topic of greener anaesthesia can be beneficial in promoting behavioural change.

Pharmacological Insights and Clinical Applications of Ciprofol: A Narrative Review.

Ciprofol (HSK3486) is a novel intravenous anaesthetic developed as an alternative to propofol, offering a safer and more effective option in anaesthesia. It works primarily by modulating the gamma-aminobutyric acid (GABA) receptors in the central nervous system, leading to sedation and hypnosis. Ciprofol's unique pharmacological properties include a rapid onset of action, shorter duration, and reduced cardiovascular and respiratory depression compared to propofol, making it particularly suitable for outpatient and day surgery procedures.Molecular changes in ciprofol appear to be superior to those of other cibenzolines; it is more potent and has a stable hemodynamic effect. It has been used in primary surgery, inpatients and outpatients, and even for sedation of intensive care patients. The reported clinical data indicate that ciprofol is a powerful sedative that is characterised by a high-enough speed of emergence from the state of anaesthesia, which is necessary for outpatient conditions and intensive operating modes. It can be considered a new and important perspective in the technology of intravenous anaesthetics with its improved pharmacological characteristics and clinical effects. With the further accumulation of clinical data, ciprofol will undeniably become an essential agent in today's anaesthetic practice and contribute to an enhancement of healthcare efficiency by providing a more secure approach to numerous kinds of surgical interventions. The purpose of the current study is to provide a review of the pharmacology and clinical use of ciprofol, a new intravenous anaesthetic agent. Various studies demonstrate the functionality and safety profile of ciprofol, which solidifies it as a potential contender for propofol. Regarding respiratory depression, hypoxemia, and injection pain during hysteroscopy, ciprofol was shown to be a relatively safer option than propofol. Ciprofol can, therefore, be recommended for intravenous anaesthesia because of its effectiveness and safety, which has been clearly demonstrated. Randomised trials uniformly report the ability to achieve quicker onset of sedation and lower risk with the agent compared to propofol. These findings imply that ciprofol has many benefits concerning a variety of applications in patients due to a lower rate of adverse reactions and increased patient comfort.

Anesthetic-sparing effect of dexmedetomidine during total intravenous anesthesia for children undergoing dental surgery: A randomized controlled trial.

Dexmedetomidine, an α2-adrenergic agonist, reduces propofol and remifentanil requirements when used as an adjunct to total intravenous anesthesia in adults, but studies in a pediatric population are sparse. This study investigates the magnitude of dose-sparing effects of a postinduction dexmedetomidine bolus on propofol and remifentanil requirements during pediatric surgery. In this randomized, double-blind, controlled trial, children aged 2-10 years undergoing elective dental surgery were assigned to one of four groups: placebo, 0.25 mcg/kg dexmedetomidine, 0.5 mcg/kg dexmedetomidine, and 1 mcg/kg dexmedetomidine. Maintenance with fixed-ratio propofol and remifentanil total intravenous anesthesia followed a bispectral index (BIS)-guided algorithm designed to maintain a stable depth of anesthesia. The primary outcomes were time-averaged maintenance infusion rates of propofol and remifentanil. Secondary outcomes in the postanesthetic care unit included sedation scores, pain scores, and time to discharge. Data from 67 patients were available for analysis. The median [interquartile range] propofol infusion rate was lower in the 1 mcg/kg dexmedetomidine group (180 [164-185] mcg/kg/min) versus placebo (200 [178-220] mcg/kg/min): percent change -10.0%; 95% CI -2.4 to -19.8; p = 0.013. The remifentanil infusion rate was also lower in the 1 mcg/kg dexmedetomidine group (0.089 [0.080, 0.095] mcg/kg/min) versus placebo (0.103 [0.095, 0.106] mcg/kg/min): percent change, -13.7%; 95% CI -5.47 to -21.0; p = .022. However, neither propofol nor remifentanil infusion rates were significantly different in the 0.25 or 0.5 mcg/kg dexmedetomidine groups. In the postanesthesia care unit, there were no differences in pain or sedation scores, and time to discharge was not significantly prolonged in any dexmedetomidine group. Dexmedetomidine 1 mcg/kg reduced the propofol and remifentanil requirements during maintenance of anesthesia in children when administered as a postinduction bolus. ClinicalTrials.gov: NCT03422978, date of registration 2018-02-06.

Clinical evaluation of bispectral index‐guided closed‐loop infusion of propofol for preschool children: A multi‐center randomized controlled study

ABSTRACTImportanceThe closed‐loop infusion system can automatically adjust and maintain the depth of anesthesia by using the propofol target‐controlled infusion (TCI) model under the feedback guidance of the bispectral index (BIS).ObjectiveTo evaluate the safety and superiority of closed‐loop TCI of propofol guided by BIS during maintenance of generalized intravenous anesthesia for preschool children.MethodsA total of 120 children aged 1–6 years were enrolled and were divided into a closed‐loop feedback group (Group C) and an open‐loop manual control group (Group O), with 60 participants in each group. For anesthesia maintenance, the propofol infusion rate was adjusted by the injection system under the guidance of BIS in Group C and was manually adjusted by anesthesiologists according to the BIS and clinical experience in Group O, to maintain a BIS level of 50. The time ratio of adequate anesthesia (40 ≤ BIS ≤ 60), light anesthesia (BIS > 60), and deep anesthesia (BIS < 40) were recorded.ResultsA total of 119 patients (59 in Group C and 60 in Group O) were enrolled in the study. Group C demonstrated a higher time ratio of adequate anesthesia (P = 0.014) compared to Group O. The time ratio of light anesthesia and the global score was lower in Group C than in Group O (P = 0.010, P = 0.015, respectively). The frequency of adjustment per unit of time was higher in Group C for propofol (P < 0.001), while it was lower for remifentanil (P = 0.010).InterpretationBIS‐guided closed‐loop infusion of propofol is safe and effective for preschool children. The depth of anesthesia is controlled more accurately and smoothly.

Toward Model-Informed Precision Dosing for Remimazolam: A Population Pharmacokinetic-Pharmacodynamic Analysis.

Remimazolam, widely used for procedural sedation and general anesthesia, is a new ultra short-acting benzodiazepine for intravenous sedation and anesthesia. We aim to characterize the pharmacokinetics/pharmacodynamics (PK/PD) of remimazolam and its metabolite CNS 7054 in healthy Chinese volunteers using population analysis and suggest an optimal dosing regimen for sedation therapy. Data were collected from a single-center, placebo-controlled, randomized, and dose-escalation clinical pharmacology study. Forty-six healthy volunteers received a single infusion dose of remimazolam, while nine healthy subjects received a continuous infusion of remimazolam. A population PK/PD model was established and RxODE and Shiny in R were used to design the remimazolam dosing regimens. A three-compartment model best described the PK of remimazolam and a two-compartment model with one transit compartment was adopted for CNS 7054. The relationship between exposure and the bispectral index was best described using an effect compartment model with an inhibitory sigmoid model. Additionally, a web-based dashboard was developed to provide individualized dosing regimens, complemented by a graphical illustration of the PK/PD profiles of the proposed dosing regimen. The established population PK/PD model characterized the dose-exposure-response relationship of remimazolam well, which could be applied to optimize individual dosing regimens.

Flow-mediated dilation facilitates radial artery cannulation in patients undergoing intravenous general anesthesia: A prospective randomized controlled trial.

Flow-mediated dilation (FMD) is commonly used as a diagnostic tool to assess endothelial function, and compared with other methods for stimulating radial artery dilation, FMD offers several advantages such as non-invasiveness, ease of execution, minimal equipment requirements, and negligible risk. The study aimed to investigate the effect of FMD in facilitating radial arterial cannulation in the context of intravenous general anesthesia. Eighty patients undergoing intravenous general anesthesia and requiring radial artery cannulation were randomized 1:1 to the FMD group and control group. Patients in the FMD group received an upper arm occlusion for 5 min after anesthesia induction, and the cuff was placed without inflation for the equivalent duration in the control group. The primary outcome was first-attempt success rate. Secondary outcomes were the diameter and percentage of dilation of radial artery, overall success rate, total number of attempts, cannulation time, and occurrence of procedure-related complications. Intravenous anesthetic agents significantly dilated the radial artery (p < 0.05), which was further increased by FMD. An increase in both the first-attempt and overall success rate of radial artery cannulation was demonstrated with the use of FMD (67.5% vs 42.5%, p < 0.05). The total number of attempts needed to cannulate the radial artery was reduced in the FMD group as compared with the control group (p < 0.05), but no differences in cannulation time and procedure-related complications were found between the two groups (p > 0.05). FMD induced by a 5-min upper arm occlusion may facilitate radial artery cannulation in patients undergoing intravenous general anesthesia.

Analgesic Effect of Dexmedetomidine-Nalbuphine Combination vs. Dexmedetomidine Alone in Donkeys Undergoing Field Castration under Total Intravenous Anesthesia.

This study evaluated the antinociceptive effect of dexmedetomidine-nalbuphine vs. dexmedetomidine alone in jacks undergoing field castration under total intravenous anesthesia. Jacks were premedicated with intravenous (IV) dexmedetomidine (5 µg/kg), either alone (Group D, n = 6) or in combination with 0.3 mg/kg nalbuphine (Group DN, n = 6). IV ketamine (1.5 mg/kg) and propofol (0.5 mg/kg) were used to induce general anesthesia, which was maintained by a continuous propofol (0.2 mg/kg/min) IV infusion. The quality of anesthesia, analgesia, and recovery were evaluated. A simple descriptive scale (SDS) was used to measure pain from the recovery time to 6 h later. The DN group exhibited improvements in analgesic and recovery quality and SDS of pain at 1-, 2-, and 3-h post-recovery. There was an apparent improvement in cardiac status, as evidenced by the enhanced heart rate and electrocardiogram findings compared to group D during surgery and recovery time. The DN group had a lower level of inflammatory cytokines, both during the surgery and shortly after recovery. Therefore, the dexmedetomidine-nalbuphine combination prior to IV anesthesia of ketamine and propofol in jacks undergoing field castration resulted in a stable surgical plane of anesthesia, improved antinociception, less pain postoperatively, and better cardiac stability.

The Role of Intravenous Anesthetics for Neuro: Protection or Toxicity?

The primary intravenous anesthetics employed in clinical practice encompass dexmedetomidine (Dex), propofol, ketamine, etomidate, midazolam, and remimazolam. Apart from their established sedative, analgesic, and anxiolytic properties, an increasing body of research has uncovered neuroprotective effects of intravenous anesthetics in various animal and cellular models, as well as in clinical studies. However, there also exists conflicting evidence pointing to the potential neurotoxic effects of these intravenous anesthetics. The role of intravenous anesthetics for neuro on both sides of protection or toxicity has been rarely summarized. Considering the mentioned above, this work aims to offer a comprehensive understanding of the underlying mechanisms involved both in the central nerve system (CNS) and the peripheral nerve system (PNS) and provide valuable insights into the potential safety and risk associated with the clinical use of intravenous anesthetics.

Comparison of 0.5% lignocaine versus 0.2% ropivacaine in intravenous regional anesthesia (Bier’s block) in upper limb surgeries

Comparison of 0.5% lignocaine versus 0.2% ropivacaine in intravenous regional anesthesia (Bier’s block) in upper limb surgeries

Comparing the Hemodynamic Effects of Intravenous and Volatile Anesthesia in Patients with End Stage Renal Disease Undergoing Laparoscopic Implantation of Peritoneal Dialysis Catheter in a Randomized Double-Blind Clinical Trial

Background: Due to the associated hypertension and cardiovascular disease in patients with ESRD hemodynamic changes during operations are detrimental and may be life-threatening. Therefore, hemodynamic stability is an important criterion in selecting the anesthetic approach. Methods: 72 ASA class III/IV, ESRD Patients were studied in randomized double blind clinical trial. They were divided into two groups by four-block randomization. A group of patients were induced and maintained by etomidate and second of patients were induced by Na thiopental and maintained by isoflurane. Systolic, diastolic and mean arterial blood pressure and heart rate were measured at interval of pre and post induction, postintubation, pre and post abdominal insufflation during and at the end of surgery and in recovery. The total BP modulators were recorded and postoperative nausea and vomiting was registered in the recovery. Data were analyzed by STATA version 12. Results: There was no significant difference in physical characteristics between two groups. There was no statistical difference between the groups in SBP and HR (P&gt;0.05), although DBP fluctuation&gt;20% at interval postinduction and prior to abdominal insufflation during surgery and at the end of surgery, was significantly higher in the isoflurane group of patients. (P=0.004, 0.001, 0.003 and 0.009, respectively). Also, the MAP fluctuation at interval of post induction, preinsufflation and at the end of surgery was significantly higher in isoflurane of patients. (P=0.04, 0.001, and 0.02, respectively). Conclusion: The group anesthetized with isoflurane had a higher hemodynamic fluctuation, compared to the group anesthetized with etomidate. As hemodynamic changes are critical in patients with ESRD, etomidate is a more appropriate anesthetic choice for implantation of peritoneal dialysis catheter by laparoscopic approach.

Opioid-free anesthesia with esketamine-dexmedetomidine versus opioid-based anesthesia with propofol-remifentanil in shoulder arthroscopy: a randomized controlled trial

BackgroundOFA (Opioid-free anesthesia) has the potential to reduce the occurrence of opioid-related adverse events and enhance postoperative recovery. Our research aimed to investigate whether OFA, combining esketamine and dexmedetomidine, could serve as an alternative protocol to traditional OBA (opioid-based anesthesia) in shoulder arthroscopy, particularly in terms of reducing PONV (postoperative nausea and vomiting).MethodsA total of 60 patients treated with shoulder arthroscopy from September 2021 to September 2022 were recruited. Patients were randomly assigned to the OBA group (n = 30) and OFA group (n = 30), receiving propofol-remifentanil TIVA (total intravenous anesthesia) and esketamine-dexmedetomidine intravenous anesthesia, respectively. Both groups received ultrasound-guided ISBPB(interscalene brachial plexus block)for postoperative analgesia.ResultsThe incidence of PONV on the first postoperative day in the ward (13.3% vs. 40%, P < 0.05) was significantly lower in the OFA group than in the OBA group. Moreover, the severity of PONV was less severe in the OFA group than in the OBA group in PACU (post-anesthesia care unit) (0 [0, 0] vs. 0 [0, 3], P<0.05 ) and in the ward 24 h postoperatively ( 0 [0, 0] vs. 0 [0, 2.25], P<0.05). Additionally, the OFA group experienced a significantly shorter length of stay in the PACU compared to the OBA group (39.4 ± 6.76 min vs. 48.7 ± 7.90 min, P < 0.001).ConclusionsCompared to the OBA with propofol-remifentanil, the OFA with esketamine- dexmedetomidine proved to be feasible for shoulder arthroscopy, resulting in a reduced incidence of PONV and a shorter duration of stay in the PACU.Trial registrationThe Chinese Clinical Trial Registry (No: ChiCTR2100047355), 12/06/2021.

Association of patient characteristics with postoperative opioid consumption following cesarean delivery: a single center retrospective study

Background The primary aim of our study was to determine which patient characteristics were associated with opioid consumption following cesarean delivery. Methods The Baylor Scott & White Research Institute institutional review board approved this study (024-178). Patients who underwent cesarean delivery at Baylor Scott & White Medical Center – Temple with single injection or combined spinal epidural anesthesia in 2023 were eligible for inclusion. We examined the medical records of 300 patients, calculated the 24-hour opioid consumption for each, and compared the top third to the low group in a bivariate analysis and then performed a multivariate logistic regression. Results One hundred thirty-one patients had no opioid consumption in the first 24 postoperative hours, and 100 patients had a morphine milligram consumption of 30 to 117.5 mg. A multivariate logistic regression determined that patients in the higher opioid consumption cohort were more likely to have received combined spinal epidural anesthesia (odds ratio 2.079; 95% confidence interval 1.149, 3.762; P = 0.02) and administration of intravenous dexmedetomidine in the intraoperative period (odds ratio 2.542; 95% confidence interval 1.038, 6.224; P = 0.04). Conclusion Intraoperative administration of intravenous dexmedetomidine and combined spinal epidural anesthesia was associated with increased postoperative opioid consumption following cesarean delivery.

Efficacy of Ultrasound-Guided Intercostal Nerve Block on Pain Management and Physiological Outcomes in Breast Cancer Mastectomy: A retrospective study.

To evaluate the efficacy of ultrasound-guided intercostal nerve block in managing pain and physiological responses in patients undergoing radical mastectomy for breast cancer. A retrospective study analyzed 120 patients scheduled to undergo radical mastectomy in our hospital between January 2022 and December 2023. Depending on the type of anesthesia received, participants were assigned to the experimental group (60 patients) to receive ultrasound-guided intercostal nerve block and intravenous general anesthesia, or the control group (60 patients) to receive intravenous general anesthesia only. Both groups will utilize patient-controlled intravenous analgesia (PCIA) postoperatively. We will monitor and compare hemodynamic parameters, SpO2, and bispectral index (BIS) at multiple time points, and assess postoperative pain, inflammatory markers, PCIA utilization, and adverse reaction incidence. Comparative analysis showed distinct trends in heart rate, mean arterial pressure (MAP), BIS, and SpO2 across various surgical stages between groups. Notably, MAP values were consistently higher and less variable in the experimental group during surgery (P < .05). Pain assessments at 4, 12, and 24 hours postoperatively in both quiet and coughing states revealed significantly milder pain in the experimental group (P < .05). Preoperative inflammatory markers (PGE2, TNF-α, IL-6, MCP-1) were similar between groups; however, 24 hours post-surgery, the experimental group showed significantly lower levels of PGE2, IL-6, and MCP-1 (P < .05). Sufentanil consumption during surgery and PCIA use were notably lower in the experimental group (P < .05). The experimental group also experienced fewer anesthesia-related adverse reactions (8.33%) compared to the control group (25.00%) (P < .05). Ultrasound-guided intercostal nerve block significantly improves hemodynamic stability, reduces postoperative inflammatory markers, lowers the need for sufentanil, and minimizes adverse reactions in patients undergoing radical mastectomy for breast cancer.

Effect of A118G (rs1799971) single-nucleotide polymorphism of the μ-opioid receptor OPRM1 gene on intraoperative remifentanil requirements in Japanese women undergoing laparoscopic gynecological surgery.

Abundant data are available on the effect of the A118G (rs1799971) single-nucleotide polymorphism (SNP) of the μ-opioid receptor OPRM1 gene on morphine and fentanyl requirements for pain control. However, data on the effect of this SNP on intraoperative remifentanil requirements remain limited. We investigated the effect of this SNP on intraoperative remifentanil requirements. We investigated 333 Japanese women, aged 21-69 years, who underwent laparoscopic gynecological surgery for benign gynecological disease under total intravenous anesthesia at Juntendo University Hospital. Average infusion rates of propofol and remifentanil during anesthesia and the average bispectral index (BIS) during surgery were recorded. Associations among genotypes of the A118G and phenotypes were examined with the Mann-Whitney U test. The average propofol infusion rate was not different between patients with different genotypes. The average remifentanil infusion rate was significantly higher in patients with the AG or GG genotype than the AA genotype (p = 0.028). The average intraoperative BIS was significantly higher in patients with the GG genotype than the AA or AG genotype (p = 0.039). The G allele of the A118G SNP was associated with higher intraoperative remifentanil requirements and higher intraoperative BIS values but was not associated with propofol requirements. Given that remifentanil and propofol act synergistically on the BIS, these results suggest that the G allele of the A118G SNP is associated with lower effects of remifentanil in achieving adequate intraoperative analgesia and in potentiating the sedative effect of propofol on the BIS.

Effects of Total Intravenous Anesthesia on Circadian Rhythms in Patients Undergoing Cardiac Transcatheter Closure

Objective To evaluate the effects of total intravenous anesthesia on the circadian rhythms in the patients undergoing cardiac transcatheter closure. Methods Thirty patients undergoing cardiac transcatheter closure under elective intravenous anesthesia were included in this study.Paired t-tests were performed to compare the mRNA levels of the genes encoding circadian locomotor output cycles kaput(CLOCK),brain and muscle ARNT-1 like protein-1(BMAL1),cryptochrome 1(CRY1),and period circadian clock 2(PER2),the Munich Chronotype Questionnaire(MCTQ)score,and the Pittsburgh Sleep Quality Index(PSQI)score before and after anesthesia.Multiple stepwise regression analysis was performed to screen the factors influencing sleep chronotype and PSQI total score one week after surgery. Results The postoperative mRNA level of CLOCK was higher [1.38±1.23 vs.1.90±1.47;MD(95%CI):0.52(0.20-0.84),t=3.327,P=0.002] and the postoperative mRNA levels of CRY1 [1.56±1.50 vs.1.13±0.98;MD(95%CI):-0.43(-0.81--0.05),t=-2.319,P=0.028] and PER2 [0.82±0.63 vs.0.50±0.31;MD(95%CI):-0.33(-0.53--0.12),t=-3.202,P=0.003] were lower than the preoperative levels.One week after surgery,the patients presented advanced sleep chronotype [3:03±0:59 vs.2:42±0:37;MD(95%CI):-21(-40--1),t=-2.172,P=0.038],shortened sleep latency [(67±64)min vs.(37±21)min;MD(95%CI):-30.33(-55.28--5.39),t=-2.487,P=0.019],lengthened sleep duration [(436±83)min vs.(499±83)min;MD(95%CI):62.80(26.93-98.67),t=3.581,P=0.001],increased sleep efficiency [(87.59±10.35)% vs.(92.98±4.27)%;MD(95%CI):5.39(1.21-9.58),t=2.636,P=0.013],decreased sleep quality score [1.13±0.78 vs.0.80±0.71;MD(95%CI):-0.33(-0.62--0.05),t=-2.408,P=0.023],and declined PSQI total score [6.60±3.17 vs.4.03±2.58;MD(95%CI):-2.57(-3.87--1.27),t=-4.039,P<0.001].Body mass index(BMI)(B=-227.460,SE=95.475,t=-2.382,P=0.025),anesthesia duration(B=-47.079,SE=18.506,t=-2.544,P=0.017),and mRNA level of PER2(B=2815.804,SE=1080.183,t=2.607,P=0.015)collectively influenced the sleep chronotype,and the amount of anesthesia medicine(B=0.067,SE=0.028,t=2.385,P=0.024)independently influenced the PSQI one week after surgery. Conclusion Total intravenous anesthesia can improve sleep habits by advancing sleep chronotype.BMI,anesthesia duration,and mRNA level of PER2 collectively influence sleep chronotype one week after surgery.The amount of anesthesia medicine independently influences the PSQI total score one week after surgery.

Environmental impact of anesthetic drugs.

The environmental impact of anesthesia far exceeds that of other medical specialties due to our use of inhaled anesthetic agents (which are potent greenhouse gases) and many intravenous medications. Calls for reducing the carbon footprint of anesthesia are ubiquitous in the anesthesia societies of developed nations and are appearing in proposed changes for hospital accreditation and funding in the United States. The body of research on atmospheric, land and water impacts of anesthetic pharmaceuticals is growing and generally reinforces existing recommendations to reduce the greenhouse gas emissions of anesthesia care. The environmental impact of anesthesia care should factor into our clinical decisions. The onus is on clinicians to safely care for our patients in ways that contribute the least harm to the environment. Intravenous anesthesia and regional techniques have less environmental impact than the use of inhaled agents; efforts to reduce and properly dispose of pharmaceutical waste are central to reducing environmental burden; desflurane should not be used; nitrous oxide should be avoided except where clinically necessary; central nitrous pipelines should be abandoned; low fresh gas flows should be utilized whenever inhaled agents are used.