Inhalation Anesthetic Sevoflurane Research Articles

PERIOPERATIVE METABOLISM IN PATIENTS WITH THYROTOXICOSIS, POSSIBILITIES OF ITS CORRECTION

In the past, thyroid surgery has been the most common cause of thyroid storm, but recently, preoperative drugs that create a euthyroid state before surgery have somewhat improved treatment outcomes. Therefore, the anesthesia of such operations is very important.
 The aim of this work: to evaluate the possibility of using dexmedetomidine for perioperative correction of metabolism in thyroidectomy under general anesthesia in patients with thyrotoxicosis.
 Materials and methods. The study was prospective, not randomized. The study involved 137 patients (53 men, 84 women, aged 21 to 76 years) with thyrotoxicosis, who underwent planned thyroidectomy under general anesthesia, using the inhalation anesthetic sevoflurane and the narcotic analgesic fentanyl, in low-flow artificial lung ventilation. Perioperative monitoring was complemented by the use of indirect calorimetry. The degree of preoperative risk of patients is ASA III-IV. In group I (n=71), situationally, during the operation, with a heart rate of > 90 beats/min, a selective β-blocker esmolol hydrochloride was administered intravenously (25-50 μg×kg-1×min-1) under the control of ECG and hemodynamic parameters until the heart rate normalizes. In group II (n=66) - dexmedetomidine – 0,1 μg×kg-1×h-1.
 Results and discussions. The initial metabolic parameters in both groups were high and amounted, respectively, 830±15 cal×min-1×m-2 in group I and 832 ± 13 cal×min-1× m-2 in group II, which exceeded their basal metabolic rate: in group I - by 54,9% and in group II - by 58,5% (p <0.01). At the stage of induction of anesthesia in group I, a depression of the hemodynamic profile was revealed, probably associated with the effect of the introduction of esmolol hydrochloride, which led to a decrease in oxygen transport without metabolic disturbances. At the stages of mobilization and removal of the thyroid gland, manifestations of hyperdynamia and hypermetabolism were observed in both groups. Metabolism at these stages, in group II, respectively, was lower, by 9,3% and 10,1%, than in group I. The degree of metabolic disorder, in group I, was 42,8% ± 2,3 % and 32,6 ± 1,8%, in group II – 31,2 ± 1,6% and 22,3 ± 1,2% (p <0.05). The blood cortisol level in group I was higher than in group II (p <0.05).
 Conclusions. Perioperative energy monitoring using indirect calorimetry allows timely detection of metabolic disorders and appropriate pathogenetic correction. The use of dexmedetomidine at a dose of 0.1 μg × kg-1 × h-1 is quite effective as an intravenous adjuvant for general anesthesia during thyroidectomy in patients with thyrotoxicosis.

BLOOD CORTISOL CONCENTRATION, HEMODYNAMICS AND METABOLISM OF PATIENTS WITH SECONDARY HYPERPARATHYROIDISM, POSSIBILITIES OF PERIOPERATIVE CORRECTION

Secondary hyperparathyroidism (SHPT) affects a majority of patients with chronic kidney disease (CKD) of stage 3 or worse with manifestations of chronic renal failure (CRF) who undergo hemodialysis. Most of them have severe metabolic disorders, metabolic acidosis and a range of disorders associated with hyperparathyroidism and require parathyroid surgery (PTS). Aim of research. To assess the possibilities of metabolic correction in patients with SHPT with PTS, depending on the level of blood cortisol. Materials and methods. The study was carried out in the clinic of SIS «RPC PCM» SAD, Kyiv, Ukraine, was prospective, not randomized. The study group (n=133) included patients with severe SHPT manifestations due to end-stage chronic renal failure due to CKD, who underwent PTS. Patient age: 21-75 years old. Men – 69 (51,9%), women – 64 (48,1%). The degree of preoperative risk of ASA III-IV. Surgical interventions were performed under general anesthesia using the inhalation anesthetic sevoflurane and the narcotic analgesic fentanyl under conditions of low-flow artificial ventilation. The patients underwent a personalized energy monitoring developed and implemented in our clinic, using indirect calorimetry, by determining the index of current metabolism (Metabolic Rate Index, MRI, cal min-1 m2 ), basal metabolism (Basal Metabolic Rate Index, BMRI, cal min-1 m2), target metabolism (Target Metabolic Rate Index) and severity of metabolic disorders (Metabolic Disordes, MD,% = ). The patients were divided into two groups. The first group (I,72) consisted of patients who had reference values of the morning blood cortisol level before the operation – 171,03 and higher (173-374) nmol/L. The second group (II, 61) consisted of patients who had cortisol levels below this limit (91,5-168 nmol/L). In group I, intensive perioperative therapy was standard and aimed at supporting and correcting vital signs, according International Standards for a Safe Practice of Anesthesia 2010, WFSA. In group II, patients additionally received intravenous drip of 125-250 mg of prednisolone and further situationally hydrocortisone under the control of energy monitoring indicators. Results. In 45.9% of patients with SHPT and end-stage CKD, glucocorticoid insufficiency and low metabolic rate were diagnosed, which can lead to irreversible changes in organs or the life support system and increase the risks of perioperative complications and death in PTS. Preventive and perioperative administration of glucocorticoids under the control of energy monitoring, restores homeostasis indicators. Patients with normal blood cortisol levels did not have significant metabolic disorders. It was enough for them to follow the standard protocol of perioperative intensive care. Conclusions. Mandatory preoperative monitoring of blood cortisol levels in patients with SHPT against the background of end-stage CKD, who are on programmed hemodialysis, who are planned for PTS, is required in order to achieve a differential approach to treatment: to determine the need and dose of intravenous glucocorticoids.

Volatile Anesthetic Sevoflurane Precursor 1,1,1,3,3,3-Hexafluoro-2-Propanol (HFIP) Exerts an Anti-Prion Activity in Prion-Infected Culture Cells

Prion disease is a neurodegenerative disorder with progressive neurologic symptoms and accelerated cognitive decline. The causative protein of prion disease is the prion protein (PrP), and structural transition of PrP from the normal helix rich form (PrPC) to the abnormal β-sheet rich form (PrPSc) occurs in prion disease. While so far numerous therapeutic agents for prion diseases have been developed, none of them are still useful. A fluorinated alcohol, hexafluoro isopropanol (HFIP), is a precursor to the inhalational anesthetic sevoflurane and its metabolites. HFIP is also known as a robust α-helix inducer and is widely used as a solvent for highly aggregated peptides. Here we show that the α-helix-inducing activity of HFIP caused the conformational transformation of the fibrous structure of PrP into amorphous aggregates in vitro. HFIP added to the ScN2a cell medium, which continuously expresses PrPSc, reduced PrPSc protease resistance after 24-h incubation. It was also clarified that ScN2a cells are more susceptible to HFIP than any of the cells being compared. Based on these findings, HFIP is expected to develop as a therapeutic agent for prion disease.

Analgesic Effectiveness and Improvement in Quality of Life after Using Topical Sevoflurane for an Extremely Painful Anal Fissure

AbstractPainful anal fissures could be distressing conditions that severely impair the patients' quality of life. The analgesic effectiveness of topical drugs, such as calcium-antagonists and nitrates is quite variable. The inhalational anesthetic sevoflurane is being repurposed as a topical analgesic for painful chronic wounds. We report a pioneer experience treating a painful chronic anal fissure with topical sevoflurane. A young adult male was suffering from an extremely painful chronic anal fissure, which severely affected his quality of life. The topical treatment with nitroglycerine and diltiazem gels failed. The patient agreed to the treatement with topical sevoflurane as an off-label medication, and it produced an immediate, intense, and long-lasting analgesic effect. An intense but rapidly transient burning sensation, as well as persistent but well-tolerated flatulence were the only adverse effects. The quality of life was greatly improved, and the cost of the treatment was affordable. Therefore, the off-label use of topical sevoflurane appears to be an effective alternative for the symptomatic treatment of painful anal fissures.

Intraoperative multi-pulse transcranial electric stimulation: the effect of general anesthetics impact on the excitability of the pyramidal tract

The results of intraoperative neurophysiological monitoring during neurosurgical treatment of pathological processes in the central nervous system are analyzed. The mechanisms of action of general anesthetics on the excitability of the pyramidal system during anesthesia with propofol and sevoflurane have been clarified. It has been established that anesthetics with different mechanisms differ in their effect on excitability and conductivity in the system motor neuron of the cortex pathways alpha-motor neuron. Inhalation anesthetic sevoflurane causes a slowdown in the conduction of a nerve impulse and a violation of the mechanisms of convergence of excitation on the alpha-motor neuron of the spinal cord. In this regard, during general anesthesia with sevoflurane, in order to achieve the effectiveness of transcranial electrical stimulation, the number of stimuli in the package should be increased first with a relatively high stimulation current. Under general anesthesia with propofol, the processes of convergence of excitation are not inhibited, therefore, effective electrical stimulation is achieved by increasing the stimulation current with a stable number of stimuli. With an increase in doses of general anesthetic to a level at which periodic patterns are recorded on the electroencephalogram, a deep inhibition of the excitability and conductivity of the pyramidal system occurs. Under these conditions, effective performance of transcranial electrical stimulation is achieved with submaximal values of the current strength and the number of stimuli.

The Effects of Propofol and Sevoflurane on Postoperative Delirium in Older Patients: A Randomized Clinical Trial Study.

Postoperative delirium is associated with adverse postoperative outcomes. However, whether intravenous and inhalation anesthetics are associated with different risks of postoperative delirium remains unknown. We set up to determine the incidence and duration of postoperative delirium in older patients who had surgery under the intravenous anesthetic propofol or the inhalational anesthetic sevoflurane. Participants were patients who had total hip/knee replacements and were randomized to propofol (N = 106) or sevoflurane (N = 103) anesthesia group. The Confusion Assessment Method was employed by investigators who were blinded to the anesthesia regimen to assess the incidence and duration (days of postoperative delirium per person) of postoperative delirium on postoperative days 1, 2, and 3. A total of 209 participants (71.2±6.7 years old, 29.2% male) were included in the final data analysis. The incidence of postoperative delirium was 33.0% with propofol anesthesia and 23.3% with sevoflurane anesthesia (p = 0.119, Chi-square test), and we estimated that we would need 316 participants in each arm to detect a potential statistically significant difference. Days of postoperative delirium per person were higher in the propofol (0.5±0.8) anesthesia group compared to the sevoflurane anesthesia group (0.3±0.5, p = 0.049, Student's t-test). This pilot study established a system to compare effects of different anesthetics and generated a hypothesis that propofol trended to have a higher incidence and had longer duration of postoperative delirium than sevoflurane. Additional studies with a larger sample size are needed to test this hypothesis.

Efficiency and safety of an anesthetic technique in surgical correction of congenital malformations of the lower parts of the urogenital system in children

Objective: to assess the efficiency and safety of an anesthetic technique in surgical correction of congenital malformations of the lower parts of the urogenital system in children by means of the performance of the comparative analysis of perioperative adverse events and complications, consumption of the inhalation anesthetic sevoflurane and the cost of anesthesia, and also the course of the early postoperative period. Material and methods. Depending on the type of anesthesia, all patients (127 boys) were divided into 3 clinical groups: those operated under multicomponent balanced inhalation anesthesia (group 1, n = 37), under general laryngeal mask anesthesia in combination with caudal blockade with 0.25% bupivacaine solution (group 2, n = 45), under general laryngeal mask anesthesia with caudal blockade with the combination of 0.25% bupivacaine solution and adjuvant (group 3, n = 45). Results. The performed analysis has not revealed any statistically significant distinctions in the assessment of anesthesia complications but it has found some significant distinctions in the consumption of sevoflurane, depth of anesthesia and its cost, as well as the necessity for postoperative anesthesia and introduction of analgesics, which testifies to the efficiency and safety of combined anesthesia and its economic benefit. Conclusion. The most effective, safe, and economically reasonable is the technique of combined anesthesia with the application of caudal blockade with local anesthetic solution and 0.1% adjuvant of morphine solution during surgical correction of congenital malformations of the lower parts of the urogenital system in children.

Short or moderate-time exposure to the inhalational anesthetics isoflurane and sevoflurane does not alter the marble-burying behavior in mice

Several studies suggest the involvement of glutamatergic neurotransmission in obsessive-compulsive disorder (OCD). Some NMDA glutamatergic receptor antagonists, such as the general anesthetic ketamine, have shown anti-OCD effects in preclinical and clinical studies. Therefore, we investigated whether the inhalational anesthetics isoflurane and sevoflurane, which are general anesthetics acting as NMDA receptor antagonists, would induce the same effects. To test our hypothesis, adult male Swiss mice were exposed to different concentrations of isoflurane (0.5, 1.5 or 3 %) or sevoflurane (0.8, 2.5 or 4 %) for 20 min (short-time exposure) or 1 h (moderate-time exposure) and submitted to the open field test (OFT) and the marble-burying test (MBT) in the same day (acute effect) or 7 days (long-lasting effect) after anesthetics administration. We found that single short or moderate-time exposure to isoflurane or sevoflurane, at sub-anesthetic or anesthetic concentrations, did not affect marble-burying behavior acutely or even 7 days after their administration. The same treatment schedules with isoflurane or sevoflurane did not impair total distance travelled in the OFT. A single moderate-time exposure to isoflurane (3 %) reduced, acutely, the central exploration of the open field, suggesting an anxiogenic-like effect of isoflurane in mice. Our results suggest that isoflurane and sevoflurane may not be promising anti-compulsive drugs.

Use of medetomidine, midazolam, ketamine and sevoflurane as an anesthetic protocol for domestic chickens

Changes in physiological and biochemical parameters after administration of medetomidine (MED), midazolam (MID), ketamine (KET) and a 2% of the inhalation anesthetic sevoflurane (SEVO), were investigated in domestic chickens. The anesthetic protocol began with a simultaneous intrapectoral injection (IP) of MED (50 μg/kg) and MID (0.5 mg/kg), followed by IP administration of 25 mg/kg of KET 10 min later. Anesthesia was then maintained for 30 min by 2% SEVO (with a 500 ml/min oxygen flow), using an Ayres T piece device. Heart and respiratory rates, cloacal temperature, reflex response and electrocardiogram (ECG) parameters were recorded at time cero (T0) before anesthesia (BA, baseline values), at time of MED+MID administration (T1), at time of ketamine injection (T2), 30 min after the start of SEVO inhalation (T3) and at recovery. Blood was also drawn at T0 and T3 to assess albumin, creatinine, glucose and liver enzyme concentrations. Cloacal temperature, heart and respiratory rates differed from baseline values at all time intervals during anesthesia (p<0.05). Heart rate decreased following the MED + MID injection (at T1, T2 and T3), and partially recovered by the reanimation period. Reflex response also differed between time 0 and all anesthesia time points (p<0.05). Mean amplitude of the P wave of the ECG was increased during MED + MID (T1) and KET (T2) anesthesia. The mean ST interval showed a large increase at T1, which was maintained throughout anesthesia (p <0.05). Albumin, glucose and the ALT enzyme decreased between T0 and T3. In conclusion, the use of MED+MID+KET and SEVO as an anesthetic combination altered cardiorespiratory and biochemical parameters of chickens, but no life-threatening effects were observed as a result of these changes. Hence, this drug combination can be adequately used as an anesthesia protocol in chickens.

Sensitivity of inhalation anesthetics isoflurane and sevoflurane for the drug-induced QT-interval prolongation in guinea pigs

We investigated effects of isoflurane and sevoflurane on sparfloxacin-induced QT-interval prolongation in guinea pigs under the monitoring of electrocardiogram and monophasic action potential (MAP), which was compared with those of halothane or non-inhaled anesthetics ketamine/xylazine. Intravenous administration of sparfloxacin at 3 and 10 mg/kg prolonged the QT interval and MAP duration together with bradycardic action under 4 different anesthetic conditions. The order of extent of prolongation of corrected QT interval after the administration of sparfloxacin was isoflurane ≈ sevoflurane ≈ halothane >> ketamine/xylazine, whereas that of the MAP90 at a pacing cycle length of 300 ms was halothane ≥ isoflurane ≈ sevoflurane >> ketamine/xylazine. These results suggest that isoflurane and sevoflurane as well as halothane could sensitize the heart to sparfloxacin-induced QT interval prolongation in guinea pigs.

Activation of Preoptic GABAergic or Glutamatergic Neurons Modulates Sleep-Wake Architecture, but Not Anesthetic State Transitions.

The precise mechanism of general anesthesia remains unclear. In the last two decades, there has been considerable focus on the hypothesis that anesthetics co-opt the neural mechanisms regulating sleep. This hypothesis is supported by ample correlative evidence at the level of sleep-promoting nuclei, but causal investigations of potent inhaled anesthetics have not been conducted. Here, we tested the hypothesis that chemogenetic activation of discrete neuronal subpopulations within the median preoptic nucleus (MnPO) and ventrolateral preoptic nucleus (VLPO) of the hypothalamus would modulate sleep/wake states and alter the time to loss and resumption of consciousness associated with isoflurane, a potent halogenated ether in common clinical use. We show that activating MnPO/VLPO GABAergic or glutamatergic neurons does not alter anesthetic induction or recovery time. However, activation of these neuronal subpopulations did alter sleep-wake architecture. Notably, we report the novel finding that stimulation of VLPO glutamatergic neurons causes a strong increase in wakefulness. We conclude that activation of preoptic GABAergic or glutamatergic neurons that increase sleep or wakefulness does not substantively influence anesthetic state transitions. These data indicate that the correlative evidence for a mechanistic overlap of sleep and anesthesia at the level of an individual nucleus might not necessarily have strong causal significance.

Effects of dexmedetomidine on perioperative brain protection in patients undergoing craniocerebral surgery under inhalation anesthesia with sevoflurane: a randomized controlled study

Background and objective: The inhalational anesthetic sevoflurane is often used in craniocerebral surgery for its advantages of quick onset, stable circulation, high safety, and few adverse reactions. However, it can also lead to abnormal blood pressure and heart rate, as well as restlessness and pain. Therefore, an auxiliary anesthetic is needed to help reduce adverse reactions. Dexmedetomidine is a potent and highly selective α2 adrenergic receptor agonist that has anti-anxiety, hypnotic, analgesic, sedative, and sympatholytic properties. Dexmedetomidine has been shown to reduce restlessness after sevoflurane inhalation anesthesia and minimize perioperative hemodynamic fluctuation. However, its application in craniocerebral surgery should be validated. The purpose of this study was to investigate the efficacy of dexmedetomidine in craniocerebral surgery under sevoflurane inhalation anesthesia. Subjects and methods: The prospective, single-center, randomized, controlled study will be performed in Taihe Hospital (Shiyan, China). The 1308 patients to be included in this study will be randomly divided into a trial group and control group (n = 654 patients per group) based on a table of random permutations. In both groups, sevoflurane will be used for induction of anesthesia for craniocerebral surgery. In the trial group, 1 μg/kg dexmedetomidine will be injected intravenously for 10 minutes commencing 15 minutes before anesthesia induction, and then continuously pumped at 0.3 μg/kg per hour until 30 minutes before surgery. In the control group, 0.9% sodium chloride injection will be administered in the same way and at the same injection rate. This trial was approved by the Ethics Review Committee of Taihe Hospital on December 8, 2015 (approval No. 2015GJJ-087). Protocol version: 1.0. Participants will not be blind to the study protocol or procedure, and will provide signed informed consent. Results: The primary outcome of this study is recovery time. Secondary outcomes of this study include anesthesia, recovery, and adverse events, as well as vital signs, stress index, and cerebral metabolic rate of oxygen consumption at different time points (before and after administration of the loading dose of dexmedetomidine, during anesthesia induction, at the beginning of craniocerebral surgery, during craniocerebral surgery, at the end of craniocerebral surgery, and at the time of recovery). A pilot study involving 190 patients who underwent craniocerebral surgery was performed between March 2016 and February 2017. These 190 patients randomly received either sevoflurane anesthesia (n = 95, control group) or dexmedetomidine and sevoflurane anesthesia (n = 95, trial group). Results of the pilot group showed that anesthesia time, intraoperative bleeding volume, intraoperative infusion volume, recovery time, and extubation time were similar between trial and control groups (P > 0.05). However, compared with the control group, the administered dosages of vasoactive drugs ephedrine and esmolol were significantly lower (P Conclusion: Findings from this study will help determine whether dexmedetomidine can reduce hemodynamic fluctuation, lower stress index, and protect the brain in patients who undergo craniocerebral surgery under inhalation anesthesia with sevoflurane. The results can provide evidence to support clinical application of dexmedetomidine combined with sevoflurane for craniocerebral surgery. Trial registration: This study was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR2000030459).

Sevoflurane Preconditioning plus Postconditioning Decreases Inflammatory Response with Hemodynamic Recovery in Experimental Liver Ischemia Reperfusion.

Objective The inhalation anesthetic sevoflurane has presented numerous biological activities, including anti-inflammatory properties and protective effects against tissue ischemic injury. This study investigated the metabolic, hemodynamic, and inflammatory effects of sevoflurane pre- and postconditioning for short periods in the rescue of liver ischemia-reperfusion (IR) injury using a rat model. Materials and Methods Twenty Wistar rats were divided into four groups: sham group, control ischemia group (partial warm liver ischemia for 45 min followed by 4 h of reperfusion), SPC group (administration of sevoflurane 2.5% for 15 min with 5 min of washout before liver IR), and SPPoC group (administration of sevoflurane 2.5% for 15 min before ischemia and 20 min during reperfusion). Results All animals showed a decrease in the mean arterial pressure (MAP) and portal vein blood flow during ischemia. After 4 h of reperfusion, only the SPPoC group had MAP recovery. In both the SPC and SPPoC groups, there was a decrease in the ALT level and an increase in the bicarbonate and potassium serum levels. Only the SPPoC group showed an increase in the arterial blood ionized calcium level and a decrease in the IL-6 level after liver reperfusion. Therefore, this study demonstrated that sevoflurane preconditioning reduces hepatocellular injury and acid-base imbalance in liver ischemia. Furthermore, sevoflurane postconditioning promoted systemic hemodynamic recovery with a decrease in inflammatory response.

Food and Drug Administration Warning on Anesthesia and Brain Development: Implications for Obstetric and Fetal Surgery

(Am J Obstet Gynecol. 2018;218(1):98–102) The United States Food and Drug Administration has warned against the use of general anesthetics and sedation medications for >3 hours in pregnant women in the third trimester and children younger than 3 years old. The anesthetics agents listed included midazolam, propofol, and inhalational anesthetics (isoflurane, sevoflurane, and desflurane). They claim these agents may affect the development of children’s brains.

HC-GC-MS Determination of the Inhalational Anesthetic Sevoflurane and its Specific Metabolite Hexafluoroisopropanol (HFIP) in Human Urine: Monitoring of Occupational Background Exposures

Today, sevoflurane is one of the most used inhalational anesthetics in human surgery, due to favourable pharmacological properties. However, teratogenic and neurotoxic effects resulting from chroni...

Inhalational anesthetics accelerate desensitization of acid-sensing ion channels

Acid-sensing ion channels (ASICs) are neuronal Na+ channels that are activated by extracellular acidification. Inhibiting ASICs is neuroprotective in mouse models of ischemic stroke. As inhalational anesthetics interact with many ion channels and as some of them have neuroprotective effects, we hypothesized that inhalational anesthetics modulate ASICs. We expressed different homo- and heteromeric ASICs heterologously in Xenopus oocytes. We co-applied with acidic pH the halogenated inhalational anesthetics sevoflurane, desflurane, and isoflurane and the noble gases xenon and argon at concentrations that are roughly equivalent to their minimal alveolar concentrations and analyzed their effect on current kinetics and amplitude. Sevoflurane, desflurane, and isoflurane as well as xenon and argon accelerated by a factor of ∼1.5 channel desensitization of the main ASICs of the central nervous system: homomeric ASIC1a and heteromeric ASIC1a/2a and ASIC1a/2b. Moreover, they decreased current amplitudes by ∼25%. For example, isoflurane accelerated desensitization of homomeric ASIC1a from 1.0 ± 0.4 s (mean ± SD) to 0.6 ± 0.2 s (n = 12; p = 0.0003) and decreased current amplitudes from 12.1 ± 7.5 μA to 9.3 ± 5.6 μA (n = 12; p = 0.0009). While inhalational anesthetics had similar effects on homomeric ASIC3, desensitization of ASIC1b was only accelerated by halogenated anesthetics but not noble gases; desensitization of homomeric ASIC2a was not modulated. In summary, we found a significant modulation of ASICs by different inhalational anesthetics. We conclude that ASICs should be considered as relevant targets of inhalation anesthetics.

NIR studies of cholesterol-dependent structural modification of the model lipid bilayer doped with inhalation anesthetics

The influence of cholesterol on the structure of the model lipid bilayers treated with inhalation anesthetics (enflurane, isoflurane, sevoflurane and halothane) was investigated employing near-infrared (NIR) spectroscopy combined with the Principal Component Analysis (PCA). The conformational changes occurring in the hydrophobic area of the lipid bilayers were analyzed using the first overtones of symmetric (2νs) and antisymmetric (2νas) stretching vibrations of the CH2 groups of lipid aliphatic chains. The temperature values of chain-melting phase transition (Tm) of anesthetic-mixed dipalmitoylphosphatidylcholine (DPPC)/cholesterol and dipalmitoylphosphatidylglycerol (DPPG)/cholesterol membranes, which were obtained from the PCA analysis, were compared with cholesterol-free DPPC and DPPG bilayers mixed with inhalation anesthetics.

Impact of inhalational anesthetics on postoperative cognitive function

Background:Conflict findings of the impact of inhalational anesthetics on postoperative cognitive function are reported. No systematic review has been performed to solve the problem. The aim of the study was to assess the effect of different inhalational anesthetics on postoperative cognitive function in a network meta-analysis.Methods:We will search MEDLINE, EMBASE, the Central Register of Controlled Trials in the Cochrane library, and CINAHL for randomized controlled trials or cohort studies assessing the short-term or long-term cognitive function of elderly patients (over 60 years) receiving major surgeries and inhalational anesthetics (desflurane, isoflurane, sevoflurane, halothane, and nitrous oxide) during surgery. Two reviewers will independently screen study eligibility, extract information from eligible studies, and appraise study quality. The impact of inhalational anesthetics will be assessed through: incidence of postoperative cognitive dysfunction at 1 week, 3 months, 1 year, and over 1 year after surgery; incidence of post-operative delirium; test of postoperative cognitive function.Results:The results of this systematic review and meta-analysis will be published in a peer-reviewed journal.Conclusion:To our knowledge, this systematic review will be the first to evaluate existing research on the incidence of postoperative cognitive function after inhalational anesthetics. Our study will assess the effect of different inhalational anesthetics on postoperative cognitive function.Ethics and dissemination:The review will be finished in December 2017, and the result will be published in a peer-reviewed journal or disseminated through conference posters or abstracts.Review registration number:CRD42017056675 (www.crd.york.ac.uk/PROSPERO).

ПРИМЕНЕНИЕ ИНГАЛЯЦИОННЫХ АНЕСТЕТИКОВ ВО ВРЕМЯ ИСКУССТВЕННОГО КРОВООБРАЩЕНИЯ

Protection of myocardium from ischemic and reperfusion lesions continues to be an important issue in the modern cardiac surgery. Russian and foreign publications contain a significant number of data about the protective impact of pre- and pos t-c onditioning with inhalation anesthetics (sevoflurane, isoflurane, and desflurane) on the myocardium. The article highlights that this protective action is maximum when these drugs are used during the whole operation and it means during cardiopulmonary bypass as well. Therefore, currently, the listed above inhalation anesthetics are used fairly frequent during cardiopulmonary bypass. However, the technology of inhalation anesthesia during perfusion has a number of specific features: changes in the pharmacokinetics of drugs (which provides impact on the dosing of anesthetics), design of oxygenator, which plays a certain role when the anesthetics are supplied to the blood, monitoring during inhalation anesthesia, technical assistance for this technology and important safety issues. This review describes the abov e-m entioned aspects.

Visual recognition memory is impaired in rhesus monkeys repeatedly exposed to sevoflurane in infancy

BackgroundExperimental studies in animals have shown that exposure to general anaesthesia in infancy can cause loss of cells in the central nervous system and long-term impairments in neurocognitive function. Some human epidemiological studies have shown increased risk of learning disability after repeated anaesthesia exposure in early childhood. Thus, we investigated in a highly translational rhesus monkey model, whether repeated exposure in infancy to the inhalation anaesthetic sevoflurane is associated with impaired visual recognition memory during the first two yr of life. MethodsRhesus monkeys of both sexes were exposed to sevoflurane inhalation anaesthesia on approximately postnatal day 7 and then again 14 and 28 days later, for four h each time. Visual recognition memory was tested using the visual paired comparison task, which measures memory by assessing preference for looking at a new image over a previously-viewed image. Monkeys were tested at 6–10 months of age, again at 12–18 months of age, and again at 24–30 months of age. ResultsNo memory impairment was detected at 6–10 months old, but significant impairment (reduced time looking at the novel image) was observed at 12–18 and 24–30 months old. ConclusionsRepeated exposure of infant rhesus monkeys to sevoflurane results in visual recognition memory impairment that emerges after the first yr of life. This is consistent with epidemiological studies that show increased risk of learning disability after repeated exposure to anaesthesia in infancy/early childhood. Moreover, these deficits may emerge at later developmental stages, even when memory performance is unaffected earlier in development.