Minimum Alveolar Concentration Of Sevoflurane Research Articles

Development of NMDA receptors contributes to the enhancement of electroencephalogram oscillations under volatile anesthetics in rats.

Volatile anesthetics including sevoflurane and isoflurane enhance oscillations of cortical electroencephalogram (EEG), partly by their modulations on glutamate-mediated excitatory synaptic transmission. Expression of NMDA receptors is increased during neonatal development. However, how the development of NMDA receptors influences EEG under volatile anesthesia remains unclear. Expressions of NMDA receptor subtypes (NR1, NR2A, and NR2B) during neonatal development were measured by Western blotting. MAC (minimal alveolar concentration) of isoflurane and sevoflurane that inducing loss of righting reflex (LORR) and no response to tail-clamp (immobility) were measured to verify the effect of NR1 expression on anesthetic potency during neonatal development. Cortical electroencephalogram recording was used to examine the influence of NR1 expression on the power density of EEG. The expressions of GluNR1, GluNR2A and GluNR2B receptors were gradually increased during neonatal development in cortex, hippocampus and thalamus of rats. Knockdown of NR1 enhanced the sedative potency of volatile anesthetics but not on immobility potency in postnatal day 14 (P14)-P17 rats. For cortical EEG, along with the increased concentration of volatile anesthetics, cortical slow-delta oscillations of P5 rats were inhibited, theta and alpha oscillations were not changed significantly; while these oscillations were enhanced until high anesthetic concentrations in P21 rats. Knockdown of NR1 in forebrain suppressed the enhancement of cortical EEG oscillations in P21 rats. The development of NMDA receptors may contribute to the enhancement of cortical EEG oscillations under volatile anesthetics.

Analgesic effect of dexmedetomidine in colorectal cancer patients undergoing laparoscopic surgery.

To evaluate the analgesic efficacy of intraoperative dexmedetomidine (DEX) for acute postoperative pain in colorectal cancer patients undergoing laparoscopic surgery. We retrospectively analyzed data of 190 colorectal cancer patients who had undergone laparoscopic surgery between October 2020 and May 2021 at Samsung Medical Center, Seoul, Korea, with (n=74) or without intraoperative DEX (n=85) administration. The demographic, clinical, anesthetic, and postoperative data were compared. In total, 159 patients were enrolled. Demographic and clinical data were not different between the groups. The mean arterial pressure (p<0.001) and heart rate (p<0.001) were lower in the DEX group at the end of surgery and after extubation (p=0.003, p=0.001). The minimum alveolar concentration of sevoflurane was lower in the DEX group during surgery. At the post-anesthesia care unit (PACU) admission and discharge, pain scores (p<0.001, p=0.027) and fentanyl consumption (p<0.001) were significantly lower in the DEX group. On postoperative days 1-3, pain scores and opioid consumption were not different between the groups. The incidence of postoperative complications was not different between the groups. Continuous intraoperative DEX administration had an intraoperative analgesic effect as indicated by lower hemodynamic and fentanyl consumption. Furthermore, there was immediate postoperative analgesia as suspected by the lower pain scores and fentanyl dose during the PACU. However, pain scores and opioid consumption after the PACU remained unaffected.

Sevoflurane dose and postoperative delirium: a prospective cohort analysis

BackgroundRecent trials are conflicting as to whether titration of anaesthetic dose using electroencephalography monitoring reduces postoperative delirium. Titration to anaesthetic dose itself might yield clearer conclusions. We analysed our observational cohort to clarify both dose ranges for trials of anaesthetic dose and biological plausibility of anaesthetic dose influencing delirium. MethodsWe analysed the use of sevoflurane in an ongoing prospective cohort of non-intracranial surgery. Of 167 participants, 118 received sevoflurane and were aged >65 yr. We tested associations between age-adjusted median sevoflurane (AMS) minimum alveolar concentration fraction or area under the sevoflurane time×dose curve (AUC-S) and delirium severity (Delirium Rating Scale-98). Delirium incidence was measured with 3-minute Diagnostic Confusion Assessment Method (3D-CAM) or CAM-ICU. Associations with previously identified delirium biomarkers (interleukin-8, neurofilament light, total tau, or S100B) were tested. ResultsDelirium severity did not correlate with AMS (Spearman's ρ=–0.014, P=0.89) or AUC-S (ρ=0.093, P=0.35), nor did delirium incidence (AMS Wilcoxon P=0.86, AUC-S P=0.78). Further sensitivity analyses including propofol dose also demonstrated no relationship. Linear regression confirmed no association for AMS in unadjusted (log (IRR)=–0.06 P=0.645) or adjusted models (log (IRR)=–0.0454, P=0.735). No association was observed for AUC-S in unadjusted (log (IRR)=0.00, P=0.054) or adjusted models (log (IRR)=0.00, P=0.832). No association of anaesthetic dose with delirium biomarkers was identified (P>0.05). ConclusionSevoflurane dose was not associated with delirium severity or incidence. Other biological mechanisms of delirium, such as inflammation and neuronal injury, appear more plausible than dose of sevoflurane. Clinical trial registrationNCT03124303, NCT01980511.

Minimal alveolar concentration of sevoflurane in combination with dexmedetomidine in patients with hysteroscopy: An up-down sequential allocation study.

Dexmedetomidine is commonly used in hysteroscopy surgery due to its analgesia and sedation without respiratory depression. Many studies have shown that dexmedetomidine can reduce the consumption of sevoflurane. However, the optimal end-tidal concentration of sevoflurane when it is co-administered with dexmedetomidine has not been established. The primary purpose of this study was to investigate the minimal alveolar concentration (MAC) of sevoflurane for cervical dilatation combined with different doses of dexmedetomidine in patients with hysteroscopy surgery. One-hundred patients undergoing hysteroscopy surgery were enrolled in this clinical trial. All the patients were randomly assigned into four groups (C, D1 , D2 , D3 ) and received a loading dose of dexmedetomidine (0, 0.6, 0.8 and 1.0μg/kg) over 10min before anaesthesia induction, respectively. Anaesthesia was induced in each patient with 5% sevoflurane in 100% oxygen via a facemask. A laryngeal mask (LMA) was inserted when the patient had lost consciousness and the BIS value decreased below 40. The response to cervical dilatation stimulus (movement vs non-movement) by the insert of hysteroscope was recorded. The MAC of sevoflurane was measured by up and down sequential method of Dixon and Mood and centred isotonic regression analysis. The calculated MAC of sevoflurane using up-and-down method of Dixon and Mood in patients with hysteroscopy surgery was (1.90 ± 0.13)%, (1.23 ± 0.16)%, (1.03 ± 0.10)% and (0.93 ± 0.08)% in groups C, D1 , D2 and D3 , respectively. The administration of dexmedetomidine can significantly decrease the MAC of sevoflurane for hysteroscopy surgery. However, a ceiling effect of the reduction was observed when the dose of dexmedetomidine was higher than 0.8μg/kg.

Jinekolojik Cerrahide Taze Gaz Akımının Derlenme Ajitasyonu Üzerine Etkileri: Klinik Bir Çalışma

ABSTRACT Objective: This prospective study aimed to determine whether low flow anesthesia (LFA) has an effect on emergence agitation in women who underwent laparotomic gynecologic surgeries. Method: Sixty four female patients were enrolled in this prospective randomized study. The patients were randomly allocated into two groups: Group 2 and Group 0.5. The fresh gas flow (FGF) rate was set at 4 L min-1 in both groups, initially. When all patients reached 1 minimum alveolar concentration of sevoflurane, the FGF rate was reduced to 2 L min-1 in Group 2 and 0.5 L min-1 in Group 0.5. For Group 0.5, vapor was closed 15 minutes before the end of surgery, while it was closed at the end of the operation for Group 2. At the end of the surgery, the FGF rate was increased to 4 L min-1. Emergence agitation was assessed using the Riker Sedation Agitation Scale (SAS) in the post-anesthesia care unit at 5, 10, 20 and 30th minutes. Results: Emergence agitation was observed in 5 patients, no significant difference was found between two groups. For all evaluation times, number of patients with SAS=4 was significantly higher in Group 0.5, while the number of patients with SAS&lt;4 was significantly higher in Group 2 (p&lt;0.05). Conclusion: The number of patients who are calm and cooperative was higher in LFA. Keywords: Emergence agitation, general anesthesia, fresh gas flow

Effects of Etco2 on the Minimum Alveolar Concentration of Sevoflurane that Blunts the Adrenergic Response to Surgical Incision: A Prospective, Randomized, Double-Blinded Trial.

CO2 has anesthetic potency and effectively influences the circulatory system. We investigated the effects of Etco2 on the minimum alveolar concentration of sevoflurane that blunts the adrenergic response to surgical incision (MAC-BAR) in patients undergoing radical surgery for gastric carcinoma. Ninety patients undergoing radical gastric-carcinoma surgery under general anesthesia were enrolled and randomly assigned into 3 groups. After intubation, the Etco2 in group L (n = 30), group N (n = 30), and group H (n = 30) was adjusted to 25 mm Hg ≤ Etco2 <30 mm Hg, 30 mm Hg ≤ Etco2 < 40 mm Hg, and 40 mm Hg ≤ Etco2 < 45 mm Hg, respectively, by changes in controlled ventilation. Hemodynamics and depth of anesthesia were observed before and after skin incision. The MAC-BAR of sevoflurane for each group was determined using an up-and-down sequential-allocation technique. To obtain 7 crossovers, 25, 26, and 26 patients were used in group L, group N, and group H, respectively. The MAC-BAR of sevoflurane using the up-and-down method for group H was significantly lower than that for group L (2.3% [95% confidence interval {CI}, 2.2-2.4] vs 2.9% [95% CI, 2.7-3.0]; difference, -0.6% [95% CI, -0.7 to -0.4], P < .001) and group N (2.3% [95% CI, 2.2-2.4] vs 2.8% [95% CI, 2.8-2.9]; difference, -0.5% [95% CI, -0.7 to -0.4], P < .001), while no significant difference was found between group L and group N (P = 1.000). Higher Etco2 levels (Etco2 values equal to 40 mm Hg or higher) can effectively decrease the MAC-BAR of sevoflurane in patients undergoing radical surgery for gastric carcinoma.

An Entropy-Based Prospective Randomized Controlled Trial to Evaluate the Analgesic and Hypnotic Effects of Equipotent Doses of Sevoflurane and Isoflurane in Patients Presenting for Spine Surgeries.

Objectives Minimal alveolar concentration (MAC) of anesthetic agents has been considered a suitable measure of the potency of inhalational anesthetics. Furthermore, it is assumed that equi-MAC concentrations of different anesthetic agents have a similar potency in suppressing responses to painful stimuli. Isoflurane and sevoflurane are two commonly used volatile anesthetic agents in spine surgeries. Therefore, these agents' hypnotic and analgesic potencies should be distinguished and comprehended for the optimal administration of anesthesia. Consequently, we undertook this study to compare the analgesic and hypnotic potencies between these agents at equi-MAC concentrations, using the entropy monitor. Materials and Methods Forty patients undergoing lumbar spine surgery were randomly assigned to two groups receiving either isoflurane ( n = 20) or sevoflurane ( n = 20). After induction, maintenance of anesthesia was done with age-corrected 1.0 MAC of either isoflurane or sevoflurane. A standardized noxious stimulus was provided to all the patients after achieving a steady state of 1.0 MAC. The state entropy (SE), response entropy (RE), and RE–SE were recorded at baseline, prestimulus, and poststimulus time points in both groups. Statistical Analyses Data are presented as frequency and percentages for categorical variables and mean ± standard deviation for continuous variables. The comparison of categorical variables between the two groups was made using the Fisher's exact test, and the Student's t -test was used for continuous variables. A p -value of < 0.05 was considered to be statistically significant. Results At age-corrected 1.0 MAC, there was no significant difference in the SE, RE, and RE–SE in both the groups at any time point. Conclusion Our study shows that during a steady state of age-corrected 1.0 MAC single-agent anesthesia, sevoflurane and isoflurane have comparable analgesic and hypnotic potencies as measured by entropy indices when a standardized nociceptive stimulus is provided.

Comparison of the Effect of Anesthetic Agents on Blood Levels of Parathyroid Hormone and Ionized Calcium: A Prospective Randomized Controlled Trial.

The aim of this randomized control trial is to compare the effect of anesthetic agents on blood levels of parathyroid hormone and ionized calcium. 77 American Society of Anesthesiologists I-II patients who would undergo laparoscopic cholecystectomy were enrolled into this prospective study and randomized into 3 groups with sealed envelope technique as Group S: sevoflurane, Group D: desflurane, and Group TIVA: total intravenous anesthesia. The first blood sample was used to check the baseline blood levels of parathyroid hormone and ionized calcium. In Group S or D, maintenance of anesthesia was being performed with 1 MAC (minimum alveolar concentration) sevoflurane or desflurane, respectively, while in Group TIVA, it was performed with 150 mcg/kg/min propofol and 1 mcg/kg/min remifentanil IV infusions. At the 30th minute of anesthesia and at the 1st hour of end of anesthesia, 2nd and 3rd blood samples, respectively, were used to check the blood levels of PTH and Ca. During perioperative period, hemodynamic parameters were also noted. Blood levels of parathyroid hormone at the 30th min after anesthesia were found to be significantly different between groups (P=0,01). The PTH level at the 30th min after anesthesia was found significantly higher in Group S than that of Groups D and TIVA (P=0.005 and P=0.001, respectively). Blood levels of ionized calcium at 30th min after anesthesia were found significantly different between groups (P=0,048). It was found significantly higher in Group TIVA than that in Group S (P=0.024). Desflurane seems to be the best agent for parathyroidectomy procedures. Future research studies are needed to be conducted to reach out more correct and valuable outcomes.

Comparison of Antinociceptive Properties Between Sevoflurane and Desflurane Using Pupillary Dilation Reflex Under Equivalent Minimum Alveolar Concentration: A Randomized Controlled Trial.

The pupillary dilation reflex (PDR), the change in pupil size after a nociceptive stimulus, has been used to assess antinociception during anesthesia. The aim of this study was to compare the antinociceptive properties of sevoflurane and desflurane by measuring the PDR amplitude. Seventy patients between 20 and 55 years of age were randomly allocated to receive either sevoflurane or desflurane. The PDR amplitude after an electrical standardized noxious stimulation (SNT) was measured using an infrared pupillometer under 1.0 minimum alveolar concentration (MAC). The pupil diameter was measured from 5 seconds before to 5 minutes after the SNT. The mean arterial pressure (MAP), heart rate (HR), and bispectral index (BIS) were also measured immediately before and after SNT as well as 1 minute and 5 minutes after SNT. The primary outcome was the maximum percent increase from the prestimulation value of the pupil diameter, and the secondary outcomes were the maximum percent increase from the prestimulation value of the MAP, HR, and BIS after SNT. The maximum percent increase of the pupil diameter after SNT was not different between the 2 groups (median [first quartile to third quartile], 45.1 [29.3-80.3] vs 43.4 [27.0-103.1]; median difference, -0.3 [95% confidence interval, -16.0 to 16.5]; P = .986). Before SNT, the MAP was higher under 1.0 MAC of sevoflurane than desflurane; however, the maximum percent increase of MAP, HR, and BIS was not different between the 2 groups. The amount of change in the PDR amplitude, MAP, and HR after SNT was not different between sevoflurane and desflurane anesthesia. This result might suggest that sevoflurane and desflurane may not have different antinociceptive properties at equivalent MAC.

The Effect of Pregabalin on the Minimum Alveolar Concentration of Sevoflurane: A Randomized, Placebo-Controlled, Double-Blind Clinical Trial.

BackgroundPregabalin is commonly used perioperatively to reduce post-operative pain and opioid consumption and to prevent the development of chronic pain. It has been shown to reduce anesthetic consumption in balanced anesthesia, but studies investigating its effect on the minimum alveolar concentration (MAC) of volatile anesthetics are lacking. The aim of this study was to investigate the effect of two different doses of pregabalin on the MAC of sevoflurane.MethodsIn a randomized, double-blinded, placebo controlled clinical study, 75 patients were assigned to receive placebo, 300 mg pregabalin, or 150 mg pregabalin, as a capsule 1 h before anesthesia induction with sevoflurane only. After equilibration, the response to skin incision (movement vs. non-movement) was monitored. The MAC was assessed using an up- and down-titration method.ResultsThe MAC of sevoflurane was estimated as 2.16% (95% CI, 2.07–2.32%) in the placebo group, 1.44% (95% CI, 1.26–1.70%) in the 300 mg pregabalin group, and 1.81% (95% CI, 1.49–2.13%) in the 150 mg pregabalin group. We therefore report a 33% reduction in the MAC of sevoflurane in the 300 mg pregabalin group as compared to placebo. The MAC of the 150 mg pregabalin group was reduced by 16% as compared to placebo but was not statistically significant.ConclusionsThe administration of 300 mg pregabalin reduced the MAC of sevoflurane by 33%, while the administration of 150 mg pregabalin did not significantly reduce the MAC of sevoflurane. Pregabalin use led to a small reduction in post-operative pain levels but increased side effects in a dose-dependent manner.

Pupil response to painful stimuli during inhalation anaesthesia without opioids in children.

Pupil dilation reflex measured by a pupillometer is known to be a useful parameter for assessing the response to perioperative noxious stimuli. In children, pupillometer can reflect changes after painful stimuli during anaesthesia or guide anaesthesia to reduce opioid consumption. However, to date, there are no data regarding pupil response during inhalation anaesthesia with analgesia by intravenous acetaminophen in children. We planned a prospective, single-armed study of children aged between 3 and 12 years who underwent surgery under general anaesthesia. Anaesthesia was maintained by 1 minimum alveolar concentration (MAC) of sevoflurane, and 15 mg/kg of acetaminophen was administered. Patients' left eye was examined using a pupillometer after induction, before and after skin incision and train-of-four stimulus. Pupil diameter and other pupillometric parameters were recorded. Increase in heart rate by 15% was regarded as insufficient analgesia to skin incision and indicative powers of pupillometric parameters for insufficient analgesia were examined by receiver-operating characteristics. A total of 33 patients were included. Enlarged pupil, large increase in pupil diameter and low neurological pupil index (NPi) after skin incision were good indicators of insufficient analgesia for skin incision. Children with insufficient analgesia showed abnormal NPi value. However, increase in pupil diameter and decrease in NPi were observed even in patients without increase in the heart rate after the skin incision. We suggest dilation of the pupil and decrease in NPi can indicate response to noxious stimuli in children. Regardless of sufficiency of analgesia, pupil dilation and decrease in NPi were observed after skin incision in children under general anaesthesia with 1 MAC of sevoflurane and intravenous acetaminophen.

The effect of a ketamine constant rate infusion on cardiovascular variables in sheep anesthetized at the minimum alveolar concentration of sevoflurane that blunts adrenergic responses.

To evaluate the effect of a constant rate infusion of ketamine on cardiac index (CI) in sheep, as estimated using noninvasive cardiac output (NICO) monitoring by partial carbon dioxide rebreathing, when anesthetized with sevoflurane at the previously determined minimum alveolar concentration that blunts adrenergic responses (MACBAR). 12 healthy Dorset-crossbred adult sheep. Sheep were anesthetized 2 times in a balanced placebo-controlled crossover design. Anesthesia was induced with sevoflurane delivered via a tight-fitting face mask and maintained at MACBAR. Following induction, sheep received either ketamine (1.5 mg/kg IV, followed by a constant rate infusion of 1.5 mg/kg/h) or an equivalent volume of saline (0.9% NaCl) solution (placebo). After an 8-day washout period, each sheep received the alternate treatment. NICO measurements were performed in triplicate 20 minutes after treatment administration and were converted to CI. Blood samples were collected prior to the start of NICO measurements for analysis of ketamine plasma concentrations. The paired t test was used to compare CI values between groups and the ketamine plasma concentrations with those achieved during the previous study. Mean ± SD CI of the ketamine and placebo treatments were 2.69 ± 0.65 and 2.57 ± 0.53 L/min/m2, respectively. No significant difference was found between the 2 treatments. Mean ketamine plasma concentration achieved prior to the NICO measurement was 1.37 ± 0.58 µg/mL, with no significant difference observed between the current and prior study. Ketamine, at the dose administered, did not significantly increase the CI in sheep when determined by partial carbon dioxide rebreathing.

Ethanol reduces the minimum alveolar concentration of sevoflurane in rats

A high number of trauma patients are under the influence of alcohol. Since many of them need immediate surgical procedures, it is imperative to be aware of the interaction of alcohol with general anesthesia. To counter challenges that arise from clinical studies, we designed an animal experiment in which 48 adult Wistar rats either received 1 g · kg−1 ethanol, 2 g · kg−1 ethanol or placebo via intraperitoneal application. Subsequently, they were anesthetized with an individual concentration of sevoflurane. The minimum alveolar concentration (MAC) of the different groups was assessed using Dixon’s up-and-down design and isotonic regression methods. The bootstrap estimate of the MAC of sevoflurane in the placebo group was 2.24 vol% (95% CI 1.97–2.94 vol%). In the low dose ethanol group, the bootstrap estimate was 1.65 vol% (95% CI 1.40–1.98 vol%), and in the high dose ethanol group, it was 1.08 vol% (95% CI 0.73–1.42 vol%). We therefore report that intraperitoneal application of 1 g · kg−1 or 2 g · kg−1 ethanol both resulted in a significant reduction of the MAC of sevoflurane in adult Wistar rats: by 26.3% and 51.8% respectively as compared to placebo.

Sparing effect of tramadol, lidocaine, dexmedetomidine and their combination on the minimum alveolar concentration of sevoflurane in dogs.

BackgroundProblems associated with using inhalational anaesthesia are numerous in veterinary anaesthesia practice. Decreasing the amount of used inhalational anaesthetic agents and minimising of cardiorespiratory disorders are the standard goals of anaesthetists.ObjectiveThis experimental study was carried out to investigate the sparing effect of intravenous tramadol, lidocaine, dexmedetomidine and their combinations on the minimum alveolar concentration (MAC) of sevoflurane in healthy Beagle dogs.MethodsThis study was conducted on six beagle dogs. Sevoflurane MAC was determined by the tail clamp method on five separate occasions. The dogs received no treatment (control; CONT), tramadol (TRM: 1.5 mg kg-1 intravenously followed by 1.3 mg kg-1 h-1), lidocaine (LID: 2 mg kg-1 intravenously followed by 3 mg kg-1 h-1), dexmedetomidine (DEX: 2 μg kg-1 intravenously followed by 2 μg kg-1 h-1), and their combination (COMB), respectively. Cardiorespiratory variables were recorded every five minutes and immediately before the application of a noxious stimulus.ResultsThe COMB treatment had the greatest sevoflurane MAC-sparing effect (67.4 ± 13.9%) compared with the other treatments (5.1 ± 25.3, 12.7 ± 14.3, and 40.3 ± 15.1% for TRM, LID, and DEX treatment, respectively). The cardiopulmonary variables remained within the clinically acceptable range following COMB treatment, although the mean arterial pressure was higher and accompanied by bradycardia.ConclusionsTramadol-lidocaine-dexmedetomidine co-infusion produced a remarkable sevoflurane MAC-sparing effect in clinically healthy beagle dogs and could result in the alleviation of cardiorespiratory depression caused by sevoflurane. Cardiorespiratory variables should be monitored carefully to avoid undesirable side effects induced by dexmedetomidine.

Sleep quality and emergence delirium in children undergoing strabismus surgery: a comparison between preschool- and school-age patients

BackgroundEmergence delirium (ED) is common in pediatric patients undergoing general anesthesia with sevoflurane. Preoperative sleep quality is associated with the risk factors for ED. However, research on the relationship between sleep quality and ED is limited. We aimed to investigate the relationship between ED and preoperative sleep quality in pediatric patients undergoing strabismus surgery.MethodsThis clinical trial included pediatric patients aged 4–12 years who underwent elective strabismus surgery. The patients and their parents were questioned about the patients’ preoperative sleep quality using the Pittsburgh Sleep Quality Index (PSQI) questionnaire. For anesthesia induction, thiopental (5 mg/kg) and rocuronium (0.6 mg/kg) were used, and anesthesia was maintained with sevoflurane (minimum alveolar concentration, 1–1.5). After administration of a reversal drug, extubation was performed, and the patients were transferred to a post-anesthesia recovery unit. At 10 min after extubation, the degree of ED was measured using the pediatric anesthesia emergence delirium (PAED) and Watcha scale scores.ResultsOf the 62 enrolled patients, three pediatric patients were excluded. The overall incidence of ED was 22%. A total of 59 patients were divided into the two groups. The ED group and the non-ED group comprised 13 and 46 patients. Age, height and weight were significantly lower in the ED group than in the non-ED group. Preoperative PSQI and Watcha scale score were significantly higher in the ED group than in the non-ED group. Multivariate analysis showed that age (adjusted OR [95% CI]: 0.490 [0.290–0.828], p = 0.008) and preoperative PSQI score (adjusted OR [95% CI]: 2.149[1.224–3.771], p = 0.008) was associated with ED. In sub-group analysis, PAED scale and Watcha scale scores showed a moderate correlation with preoperative sleep quality in preschool-age patients.ConclusionIn conclusion, the incidence of ED tended to be higher in younger age and poorer preoperative sleep quality in pediatric patients. In particular, the poorer sleep quality score was associated with higher incidence of ED in the preschool-age. Large-scale clinical studies and long-term follow-up studies on ED and sleep quality are required.Trial registrationThis study was registered with Clinicaltrials.gov (NCT03332407) at November 5th 2017.

Comparison of the median effective concentration (EC50) and effect of sevoflurane with or without remifentanil in cesarean section with supreme laryngeal mask under narcotrend monitoring: a randomized trial.

Remifentanil combined with sevoflurane is a standard protocol for obstetric general anesthesia (GA). In this study, we performed a randomized clinical trial to evaluate whether remifentanil has an effect on the median effective concentration (EC50) of sevoflurane and compare anesthetic outcomes of them in cesarean section with Supreme™ laryngeal mask airway (SLMA) under narcotrend monitoring. Ninety parturients with singleton births undergoing elective cesarean delivery (CD) with initial inhaled 1.0 minimum alveolar concentration (MAC) sevoflurane for anesthesia maintenance were assigned to three groups randomly and evenly: Group A (0.05 µg·kg-1·min-1 remifentanil combined with sevoflurane), Group B (0.1 µg·kg-1·min-1 remifentanil combined with sevoflurane), and Group C (normal saline combined with sevoflurane). Narcotrend was used to monitor the depth of anesthesia during the operation, with the level of anesthesia depth controlled within the D-E stage. The EC50 of sevoflurane was determined by Dixon's sequential method. The Narcotrend index, amount of bleeding, neonatal Apgar score, and corresponding treatment measures in the three groups were recorded. The results showed that the estimated EC50 of sevoflurane for obstetric GA was 0.80 MAC (95% CI: 0.63-0.95 MAC) in group A, 0.82 MAC (95% CI: 0.63-0.96 MAC) in group B, and 0.80 MAC (95% CI: 0.63-0.95 MAC) in group C. There was no statistically significant difference in the estimated EC50 of sevoflurane, time to wakefulness, Apgar score, amount of intraoperative bleeding, and postoperative bleeding within 24 hours between the three groups (all P>0.05). The addition of remifentanil at 0.05-0.1 µg·kg-1·min-1 did not change the EC50 of sevoflurane and anesthetic quality. The concentration of inhaled anesthetics can be minimized with Narcotrend monitoring. Chinese Clinical Trial Registry ChiCTR2000034512.

Effects of sevoflurane, propofol or alfaxalone on neuromuscular blockade produced by a single intravenous bolus of rocuronium in dogs

ObjectiveTo compare the effects of sevoflurane, propofol and alfaxalone on the neuromuscular blockade induced by a single intravenous bolus of rocuronium in dogs. Study designA randomized, prospective, crossover experimental study. AnimalsA total of eight adult Beagle dogs (four female, four male), weighing 8.9–15.3 kg and aged 5–7 years. MethodsThe dogs were anesthetized three times with 1.25× minimum alveolar concentration of sevoflurane (SEVO treatment) and 1.25× minimum infusion rate of propofol (PROP treatment) or alfaxalone (ALFX treatment) at intervals of ≥14 days. Neuromuscular function was monitored with train-of-four (TOF) stimulation of the peroneal nerve by acceleromyography. After recording the control TOF ratio (TOFRC), a single bolus dose of rocuronium (1 mg kg–1) was administered intravenously. The times from rocuronium administration to achieving TOF count 0 (onset time), from achieving TOF count 0 to the reappearance of TOF count 4 (clinical blockade period), from 25% to 75% of TOFRC (recovery index) and from achieving TOF count 0 to TOF ratio/TOFRC >0.9 (total neuromuscular blockade duration) were recorded. ResultsThe onset time and recovery index did not differ among the treatments. The median clinical blockade period was longer in the SEVO treatment [27.3 (26.0–30.3) minutes] than in PROP [16.6 (15.4–18.0) minutes; p = 0.002] and ALFX [22.4 (18.6–23.1) minutes; p = 0.017] treatments; and longer in the ALFX treatment than in the PROP treatment (p = 0.020). The mean total neuromuscular blockade duration was longer in the SEVO treatment (43.7 ± 9.9 minutes) than in PROP (25.1 ± 2.7 minutes; p < 0.001) and ALFX (32.5 ± 8.4 minutes; p = 0.036) treatments. Conclusions and clinical relevanceCompared with alfaxalone and propofol, sevoflurane prolonged rocuronium-induced neuromuscular blockade by a significantly greater extent in dogs.

Minimum alveolar concentration of sevoflurane required to prevent Bell’s phenomenon during examination of the eye under anaesthesia

Minimum alveolar concentration of sevoflurane required to prevent Bell’s phenomenon during examination of the eye under anaesthesia

The effect of xenon on fetal neurodevelopment following maternal sevoflurane anesthesia and laparotomy in rabbits

BackgroundThere is concern that maternal anesthesia during pregnancy impairs brain development of the human fetus. Xenon is neuroprotective in pre-clinical models of anesthesia-induced neurotoxicity in neonates. It is not known if xenon also protects the developing fetal brain when administered in addition to maternal sevoflurane-anesthesia during pregnancy. ObjectiveTo investigate the effects of sevoflurane and xenon on neurobehaviour and neurodevelopment of the offspring in a pregnant rabbit model. MethodsPregnant rabbits on post-conception day 28 (term = 31d) underwent two hours of general anesthesia with 1 minimum alveolar concentration (MAC) of sevoflurane in 30% oxygen (n = 17) or 1 MAC sevoflurane plus 50-60 % xenon in 30% oxygen (n = 10) during a standardized laparotomy while receiving physiological monitoring. A sham-group (n = 11) underwent monitoring alone for two hours. At term, the rabbits were delivered by caesarean section. On the first postnatal day, neonatal rabbits underwent neurobehavioral assessment using a validated test battery. Following euthanasia, the brains were harvested for neurohistological analysis. A mixed effects-model was used for statistical analysis. ResultsMaternal cardiopulmonary parameters during anesthesia were within the reference range. Fetal survival rates were significantly higher in the sham-group as compared to the sevoflurane-group and the fetal brain/body weight ratio was significantly lower in the sevoflurane-group as compared with the sham- and xenon-group. Pups antenatally exposed to anesthesia had significantly lower motor and sensory neurobehavioral scores when compared to the sham-group (mean ± SD; sevo: 22.70 ± 3.50 vs. sevo+xenon: 22.74 ± 3.15 vs. sham: 24.37 ± 1.59; overall p = 0.003; sevo: 14.98 ± 3.00 vs. sevo+xenon: 14.80 ± 2.83 vs. sham: 16.43 ± 2.63; overall p = 0.006; respectively). Neuron density, neuronal proliferation and synaptic density were reduced in multiple brain regions of the exposed neonates. The co-administration of xenon had no measurable neuroprotective effects in this model. ConclusionsIn rabbits, sevoflurane anesthesia for a standardized laparotomy during pregnancy resulted in impaired neonatal neurobehavior and a decreased neuron count in several regions of the neonatal rabbit brain. Co-administration of xenon did not prevent this effect.

Singular and short-term anesthesia exposure in the developing brain induces persistent neuronal changes consistent with chronic neurodegenerative disease

The potential adverse impact of inhalational anesthetics on the developing brain was highlighted by the addition of a medication warning by the U.S. Food and Drug Administration for their use in the pediatric population. To investigate mechanisms by which early life anesthesia exposure could induce long-term neuronal dysfunction, we exposed rats to 1 minimum alveolar concentration sevoflurane at 7 days of life. The animals were raised normally until adulthood (P300) prior to sacrifice and analysis of cortical tissue structure (TEM), mitochondrial quality control and biogenesis pathways (Western blot, ELISA, ADP/ATP content), and markers of oxidative stress, proteotoxicity and inflammation (Western blot, ELISA). We found that early life anesthesia exposure led to adverse changes in mitochondrial quality maintenance pathways, autophagy and mitochondrial biogenesis. Although there was an escalation of oxidative stress markers and an increase in the nuclear localization of stress-related transcription factors, cellular redox compensatory responses were blunted, and oxidative phosphorylation was reduced. We found upregulation of mitochondrial stress and proteotoxicity markers, but a significant reduction of mitochondrial unfolded protein response end-effectors, contributing to an increase in inflammation. Contrary to acute exposure, we did not find an increase in apoptosis. Our findings suggest that a limited, early exposure to anesthesia may produce lasting cellular dysfunction through the induction of a sustained energy deficient state, resulting in persistent neuroinflammation and altered proteostasis/toxicity, mimicking aspects of chronic neurodegenerative diseases.