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ObjectiveThe higher incidence of post sevoflurane agitation presents a great dilemma. This controlled study was performed to test the hypothesis that the prophylactic single dose of either dexmedetomidine or fentanyl reduces the incidence of emergence agitation post sevoflurane anesthesia in children.Patients and methodsNinety pediatric patients were scheduled for elective surgical procedures under general anesthesia and caudal block. They were randomized to one of three groups (each one is 30 patients); fentanyl group (1μg/kg), dexmedetomidine (DEX) group (0.15μg/kg), and control group. Recovery was assessed by time until eye opening on command, pain was evaluated by the children’s and infants’ postoperative pain scale (CHIPPS) and adequacy of recovery was assessed using a Modified Aldert score. Both were recorded every 15min. Behavior score was recorded in the pre- and postoperative periods.Main resultsPatients in control group obtained higher values (9.65±0.34) in the modified Aldert score than patients who received fentanyl (9.58±0.30) and dexmedetomidine (9.37±0.37). There was significant difference between dexmedetomidine and fentanyl groups For pain assessment, patients in control group suffered from pain when measured by CHIPPS (0.93±0.56) more than patients in dexmedetomidine group (0.48±0.45) and fentanyl group (0.13±0.35), with more significant pain in dexmedetomidine group when compared to fentanyl group (p

In this clinical study, effects of diazepam + ketamine HCl + sevoflurane anesthesia on vital functions and recovery duration and qualityofnine long legged buzzards were evaluated upon wing amputation. Operation was decided for long legged buzzards and heartand breathingrate, body temperature, and reflexes of long legged buzzards were evaluated before, during and after the anesthesia. Diazepam and ketamine HCl injection increased the heart rate whereas it was decreased by sevoflurane. Respiratory rate decreased upon sevoflurane application. Body temperature decreased during anesthesia. Recovery began in the 3rd minute after cessation of sevoflurane administration with return of eye reflexes and completedin the 35th minute. It was observed that although birdsrecovered from anesthesia, danger of hypothermia persisted for a long time.There was a significant difference between the respiratory and heart rates during the ketamine HCl and sevofluraneanesthesia from those in the preoperative period. However, there was no statistically significant difference between pre and post operative periods in terms of vital parameters. For the first time, effects of diazepam + ketamine HCl + sevoflurane anesthesia combination on vital parameters are evaluated in long legged buzzards in Turkey.

Background Sevoflurane may prolong the corrected QT (QTc) interval in healthy humans when administered for induction and maintenance of anesthesia. Little information is available about the dose-response relationship of sevoflurane on the QTc interval. We performed a pharmacodynamic analysis of the relationship between end-tidal sevoflurane concentration (CET) and the QTc. Methods Twenty-one patients aged 20-50 yr were enrolled in this study. Sevoflurane concentrations were progressively increased and then decreased over 15 min at the start of anesthesia; CET and automated QT interval were recorded continuously. Pharmacodynamic analysis using a sigmoid Emax model was performed to assess the concentration-effect relationship. Results Maximal CET was 4.30 ± 0.33%. Measured baseline and maximally prolonged QTc interval values were 351.7 ± 15.4 ms and 397.8 ± 17.5 ms, respectively. During sevoflurane anesthesia, increased concentrations were correlated with prolonged QTc interval. Hysteresis between the CET and QTc interval were observed and accounted for in the model. Ce50 and ke0 were 2.5 ± 1.4 and 2.0 ± 1.0, respectively. The median prediction error, median absolute prediction error, and the coefficient of determination (R) were 0.02%, 0.75%, and 0.95, respectively. The effect-site concentration (Ce50) and QTc interval data fit to a sigmoid Emax model. Conclusions Among patients receiving sevoflurane for anesthesia, QTc interval changes correlate to anesthetic level. The Ce50 for significant QTc change is at clinically relevant levels of sevoflurane anesthesia.

In liver transplantation patients under intravenous anesthesia, the vecuronium dose is known to be reduced, especially during the anhepatic phase. Volatile anesthetics potentiate a muscle relaxation effect of neuromuscular blocking agents, so the vecuronium dose is supposed to further decrease if sevoflurane is used during liver transplantation. The purpose of this study was to determine the appropriate dose of vecuronium at each phase of liver transplantation under sevoflurane anesthesia.Thirty-five patients scheduled for living donor liver transplantation because of liver cirrhosis were enrolled in this study. They were anesthetized with 1 MAC of sevoflurane and intermittent administration of fentanyl. Continuous infusion of vecuronium (0.5 mg/ml) was used for muscle relaxation, which was adjusted every 15 min for consistent muscle relaxation aimed at T1/Tc of 0.1 monitored by ulnar nerve stimulation. Vecuronium infusion was stopped after hepatic artery anastomosis was finished. The infusion rate of each operative phase-dissection, anhepatic, and neohepatic-was calculated and analyzed by one-way analysis of variance. The recovery time from train-of-four (TOF) count 1 to TOF ratio 25% was also measured.The vecuronium infusion rate of each operation phase for adequate muscle relaxation was as follows: 0.033 ± 0.009 mg/kg/h during dissection phase, 0.031 ± 0.009 mg/kg/h during anhepatic phase, and 0.026 ± 0.006 mg/kg/h during early neohepatic phase. There was a statistically significant difference between doses at each phase (P = 0.033). The recovery time from TOF count 1 to TOF ratio 25% was 103 ± 29 min.The required vecuronium dose in all phases was less than the known dose in the anhepatic phase (0.036 mg/kg/h) under midazolam-fentanyl anesthesia. In addition, the vecuronium infusion dose was not reduced in the anhepatic phase compared to the dissection phases.

BACKGROUND Propofol and sevoflurane are commonly used anesthetics for neurosurgery. The aim of the study was to compare the effects of propofol with sevoflurane on cerebral pial arteriolar and venular diameters during global brain ischemia and reperfusion. METHODS Japanese white rabbits were anesthetized with propofol (n=11), sevoflurane (n=9), or the combination of sevoflurane and intralipid (n=10). Global brain ischemia was induced by clamping the brachiocephalic, left common carotid, and left subclavian arteries for 15 minutes. Pial microcirculation was observed microscopically through closed cranial windows and measured using a digital-video analyzer. Measurements were recorded before clamping and afterward for 120 minutes. RESULTS Plasma glucose and mean arterial blood pressure increased significantly during ischemia in the propofol-anesthetized rabbits. During ischemia, pial arteriolar and venular diameters decreased significantly in all groups. After unclamping, large and small, pial arteriolar and venular diameters increased temporarily and significant dilation was observed in both sevoflurane groups. From 10 minutes after unclamping until the end of the study, large and small arterioles returned to baseline diameters in the sevoflurane groups, but decreased significantly by 10% to 20% in the propofol rabbits. Ischemia-induced adverse effects such as pulmonary edema and acute brain swelling were observed primarily in propofol-anesthetized rabbits. CONCLUSION Propofol and sevoflurane acted differently on pial vessels during reperfusion after ischemic insult. Pial arterioles and venules did not dilate immediately after reperfusion, and subsequently constricted throughout the reperfusion period in propofol-anesthetized rabbits. In contrast, pial arterioles and venules dilated temporarily and returned to baseline in sevoflurane-anesthetized rabbits.

To investigate the effects of sevoflurane on cognitive function in old Sprague-Dawley (SD) rats and the expression of insulin-like growth factor-1 (IGF-1) in CA1 region of hippocampus. Forty Sprague-Dawley rats of 12 months old were randomly divided into five groups: the normal control group; 1.5% sevoflurane I group (be tested after received 1.5% sevoflurane for 1 day); 1.5% sevoflurane II group (be tested after received 1.5% sevoflurane for 7 day); 3.0% sevoflurane I group (be tested after received 3.0% sevoflurane for 1 day) and 3.0% sevoflurane II group (be tested after received 3.0% sevoflurane for 7 day). All SD rats were received 1.5 or 3.0% sevoflurane in a special glass anesthesia box for 2 h respectively, except for the normal control group. Y-maze was used to test the ability of learning and memory after being received sevoflurane for 1 or 7 days at the same moment portion. The altered expression level of IGF-1 in the hippocampus was tested to compare its transcripts by RT-PCR analysis. The results showed that 3% sevoflurane induced the decline of cognitive function and significantly deceased the IGF-1 expression at mRNA levels at 1 day in the 3.0% sevoflurane I group when compared with the normal control group. However, there were no significant difference among the other groups when compared with normal control group. Therefore, administration of sevoflurane might temporally affect the ability of cognitive function of rats through suppressing the IGF-1 expression at mRNA levels in hippocampus.

Background The present study tested the effect of midazolam administration after sevoflurane anesthesia against emergence agitation in children in the recovery phase. Methods A total of 60 children presenting for ophthalmic surgery under sevoflurane anesthesia were randomly placed in four groups from Group I to Group IV. Before the end of the surgery, we injected normal saline 2 ml in Group I and Group IV. We administered a 2-ml mixture of midazolam 0.025 mg/kg and midazolam 0.050 mg/kg to Group II and Group III respectively. Among the patients with agitation scores 4 or 5 in the peostanesthesia care unit (PACU), Group IV patients were intravenously given a 1-ml mixture of midazolam 0.025 mg/kg and normal saline up to 3 times. Agitation parameters, anesthesia recovery times, and the total administration amounts of midazolam were measured. Results Extubation time was significantly longer and maximum agitation scores higher in Group III than in Group I. The rate of the length of the period when the agitation score was 4 or 5 out of the length of stay in the PACU was significantly lower in Group II, Group III, and Group IV than in Group I. The length of stay in the PACU was significantly longer in Group III, and Group IV than in Group I. Conclusions For pediatric patients under sevoflurane anesthesia, postoperative midazolam administration slightly prolonged the length of stay in the PACU. But it effectively reduced emergence agitation without any side effects.

セボフルラン麻酔による下腹部手術におけるレミフェンタニルの投与量の差が平均血圧 (MAP) , 心拍数 (HR) およびelectroencephalographic bispectral index (BIS) に及ぼす影響を検討した. 27名の子宮全摘術中の患者を対象とし, 麻酔をセボフルラン1%とレミフェンタニル持続投与 (L群: 0.25, M群: 0.625, H群: 1.0μg/kg/min) で行った. L群と比べてM群, H群のMAPとHRは有意に低かった. M群とH群の間ではそれらに有意差はなかった. 収縮期血圧, HRの最低値は78mmHg, 48/minであった. BISは3群間に有意差を認めなかった. レミフェンタニルは0.25～1.0μg/kg/minの間でおおむね安全に使用できたが, MAP, HRおよびBISからみて, 投与量は0.625μg/kg/minまででよいと考えられた.

Somatosensory evoked potentials (SEPs) are used to determine the spinal cord and brain function during surgical procedures. In general, SEPs are sensitive to volatile anesthetics, but little is known about the effects of anesthesia maintenance with sevoflurane on SEPs in children. Analgesics are often provided during anesthesia, and supplementary drugs may also affect the SEPs. In this prospective clinical trial of 27 healthy, 3- to 8-yr-old children, we evaluated the effects of sevoflurane anesthesia after IV induction with benzodiazepine and barbiturate on median nerve SEP. In addition, the effects of two analgesics (ketoprofen and fentanyl) on SEPs were evaluated.Median nerve SEPs were recorded before premedication with midazolam 0.1 mg/kg IV, and at three separate times during anesthesia maintenance with sevoflurane 2% end-tidal concentration in air/oxygen (after 15 min of sevoflurane inhalation), supplemented with/without ketoprofen 1 mg/kg (after 25 min) and fentanyl 1 microg/kg (after 35 min).Compared with baseline measurements, an increase both in N20 latency (P = 0.015) and in central conduction time (P = 0.001) was noted during anesthesia maintenance with sevoflurane. The administration of analgesics did not have an influence on the N20 latency or central conduction time. In children 5 to 8 yr of age, the mean cortical N20-P25 amplitude was decreased (P = 0.008). In addition, in older children, the N20-P25 amplitude decreased after the co-administration of ketoprofen and fentanyl compared with the values measured before the analgesics (P = 0.03). These decreases were not seen in the younger children.In children, anesthesia maintenance with 2% sevoflurane prolongs median SEP latencies in a manner that is similar to those reported for other volatile anesthetics. However, SEP monitoring can be done with sevoflurane inhalation, but the dosage should be adjusted due to interindividual variability. Co-administration of ketoprofen, and fentanyl did not affect the SEP latencies, but post hoc analysis suggested that older children had a decrease in cortical amplitudes.

Background Growth pattern in the electroencephalographic bicoherence spectrum has recently been found to relate to anesthetic depth, and bicoherence analysis can reflect behavior of the thalamocortical reverberating network. Because the thalamocortical network is known to represent a key factor in sleep by anesthesia, systematic and qualitative bicoherence studies of different anesthetic depths is necessary throughout all pairs of frequencies. Methods Sixteen patients were anesthetized using sevoflurane (1, 2, or 3%) combined with remifentanil (0.4 microg x kg x min). Raw electroencephalographic signals were collected, and bicoherence was estimated in all pairs of frequencies, between 0.5 and 40 Hz at 0.5-Hz intervals. Results Sevoflurane (1%) caused two main peaks, spindle frequencies (11.0 +/- 1.2 Hz, 44.7 +/- 12.3% [bicoherence growth]) and delta-theta frequencies (5.4 +/- 0.5 Hz, 33.0 +/- 8.4%), in the diagonal line of biphasic bicoherence plots. High concentrations of sevoflurane (2% and 3%) shifted these peaks to 9.8 +/- 1.1 Hz, 46.2 +/- 12.7%; 8.7 +/- 1.3 Hz, 37.2 +/- 13.7% and 4.9 +/- 0.5 Hz, 44.6 +/- 7.0%; 4.3 +/- 0.8 Hz, 45.2 +/- 10.6%, respectively. Sevoflurane caused a third bicoherence peak to appear in another heterogeneous pair frequency (pair of alpha basal frequency and its double frequency), outside the diagonal line, which also inherited the behavior of alpha bicoherence peaks at different anesthetic depths. Conclusions Sevoflurane anesthesia caused bicoherence peaks in alpha and delta-theta areas and also formed secondary third peaks. Deeper sevoflurane anesthesia shifted all bicoherence peaks to lower frequencies and caused increased bicoherence growth in the delta-theta area. The obtained features are consistent with characteristics of the thalamocortical reverberating network and suggest the importance of bicoherence analysis for the thalamic system.

Isocapnic hyperpnoea (IH) reduces recovery time from isoflurane anesthesia in animals and humans. We studied the effect of IH on the emergence profile of sevoflurane-anesthetized patients by comparing postoperative recovery variables in patients administered IH (IH group) to those recovered in the customary fashion (control group).We enrolled 30 ASA I-III patients undergoing elective gynecological surgery. Induction and maintenance of anesthesia were standardized with a protocol consisting of fentanyl, propofol, rocuronium, and sevoflurane in air/O2. Patients were randomly assigned to control (C) or IH groups at the end of the surgery. We recorded time intervals from discontinuing sevoflurane to recovery milestones.Time to tracheal extubation was much shorter in the IH group compared with group C (6.2 +/- 2.1 vs 12.3 +/- 3.8 min, respectively, P0.01). The IH group also had shorter times to initiation of spontaneous ventilation (4.2 +/- 1.7 vs 6.5 +/- 3.8 min, P = 0.047), eye opening (5.5 +/- 1.4 vs 13.3 +/- 4.4 min, P0.01), bispectral index value75 (3.9 +/- 1.1 vs 8.8 +/- 3.7 min, P0.01), leaving operating room (7.7 +/- 2.0 vs 15.3 +/- 3.4 min, P0.01), and eligibility for postanesthetic care unit discharge (67.2 +/- 19.3 vs 90.6 +/- 20.0 min, P0.01).IH accelerates recovery from sevoflurane anesthesia and shortens operating room and postanesthetic care unit stay.

All modern vapor anesthetics are capable of carbon monoxide (CO) production as a result of interaction with desiccated strong base containing carbon dioxide absorbents. In desiccated absorbents, desflurane produces the highest concentrations of CO. Sevoflurane is known to produce the nephrotoxic compound A (CA) independently from water content of the carbon dioxide absorbent. The purpose of this study was to register the average CO concentrations in forty patients receiving anesthesia with desflurane or sevoflurane after implementation of a safety protocol adapted from Woehlck et al.. This protocol was developed to prevent desiccation of the strong base containing absorbent Dragersorb 800 Plus ® . Methods: In 40 patients a low-flow anesthesia was maintained using an oxygen/air mixture with either sevoflu- rane or desflurane in combination with the CO2 absorbent Dragersorb 800 plus ® . CO and CA production was measured in the inspiratory limb of the anesthesia machine using a portable gas chromatograph, with a sampling frequency of 12 sam- ples per hour. Results: No carbon monoxide was measured in any of the desflurane or sevoflurane anesthesia's. The mean concentration of CA for anesthesia with sevoflurane was 17.1 ± 5.5 parts per million. Conclusion: With the introduction of a safety protocol no carbon monoxide was measured in anesthesia performed with desflurane or sevoflurane. Com- pound A is almost continuously detected in anesthetic procedures with the use of sevoflurane in very low concentrations. Implementation of a simple safety protocol possibly prevents desiccation of the absorbent and could subsequently reduce the risk of carbon monoxide intoxication.

Although dexmedetomidine is often used in neuroanesthesia and neuronal critical care practice, its effect on cerebral electrical activity in those with an abnormal electroencephalogram is not known. The electrocorticogram (ECoG), a sensitive method for examining the effect of drugs on cerebral electrical activity and surgical treatment for epilepsy, is usually guided by monitoring of the ECoG. We investigated the effect of dexmedetomidine on ECoG in patients with epilepsy undergoing surgery with sevoflurane.Patients with medically intractable temporal lobe epilepsy undergoing resection of the epileptic foci (n = 11) were enrolled. Under general anesthesia with 2.5% sevoflurane and end-tidal carbon dioxide tension at 30 mm Hg, ECoG was recorded by strip electrodes with eight contacts placed on the mesial temporal lobe ipsilateral to the epilepsy foci. Dexmedetomidine was given as a computer-controlled infusion to achieve target plasma concentrations of 0.5 and 1.5 ng/mL. Each concentration was maintained for 20 min and ECoG was recorded before infusion of dexmedetomidine and between the 10th and 20th min after starting infusion. The median frequency of ECoG, spectral power density of each spectral band, and number of spikes at each concentration of dexmedetomidine were compared by Kruskal-Wallis test, followed by Student-Newman-Keuls test.The median frequency of ECoG in 88 leads from all leads from all patients was significantly decreased by 1.5 ng/mL of dexmedetomidine compared with those at baseline and 0.5 ng/mL (P = 0.003 and 0.03, respectively); however, spectral power densities in the frequency bands: delta (4 Hz), theta (or =4 and8 Hz), alpha (or =8 and13 Hz), and beta (or =13 Hz), were not changed. Neither the number of leads with spikes nor the number of spikes in all leads and in the lead with highest number of spikes at baseline was affected by dexmedetomidine.Dexmedetomidine at plasma concentrations of 0.48 and 1.60 ng/mL decreased the median frequency of ECoG, but did not affect spike activity in patients with temporal lobe epilepsy anesthetized with 2.5% sevoflurane.

BACKGROUND: Recent studies showed changes in cerebral protein expression up to 3 days after desflurane anesthesia in rats. In the present study, we investigated the existence of persisting changes on the proteome level after sevoflurane anesthesia that persisted for as long as 28 days after anesthesia. METHODS: Rats were anesthetized by spontaneous inhalation of 2.4% sevoflurane in air for 3 h. Animals (n = 6 for each group) were killed either directly, 72 h, or 28 days after anesthesia. Brains were removed and subjected to global protein expression profiling based on two-dimensional gel electrophoresis and mass spectrometry. Expression factors were compared to results from untreated conscious animals at each time point. Data were statistically analyzed by ANOVA (P < 0.01) and a cut of more than two-fold change in the expression factor. RESULTS: We found 11 protein spots differentially regulated directly after anesthesia. Seventeen proteins were differentially expressed 72 h after the anesthesia. Only one spot was differentially regulated 28 days after anesthesia. The plausible targets of these differentially regulated proteins can be attributed to synaptic vesicle handling and cell-cell communication. CONCLUSIONS: Sevoflurane induced relevant changes in protein expression profiles directly and 72 h after an anesthesia with 1 MAC. Twenty-eight days after the anesthesia, all proteins except one had returned to baseline levels of abundance.

Trials 16(1), 449 (2015). doi:10.1186/s13063-015-0987-4, Published by BioMed Central, London

Bispectral index (BIS) and auditory evoked potential (AEP) monitoring require the attachment of forehead sensors, posing difficulties when the surgical field involves the forehead. This study analyzed the relationship between BIS values and AEP indices from different sites on the head to establish alternative sensor locations for AEP recording. Thirty patients scheduled for elective surgery under sevoflurane anesthesia were randomly assigned to the forehead, nose or mandible groups (n = 10 patients per group). AEP sensors were placed at the assigned position for each group and BIS sensors were placed on the forehead. BIS value and AEP index were simultaneously recorded from induction until emergence from general anesthesia. Relationships between BIS values and AEP indices were analyzed using a regression method and compared between groups using Pearson's correlation coefficients. Square regression models better expressed the relationships than linear models in all groups. The z-transformed coefficient in the forehead group was the same as the nose group (p = 0.24) and significantly different in the mandible group (p = 0.0046). These findings suggest that AEPs can be accurately recorded from sensors placed on the nose. Nasal AEP might be useful for monitoring electrical activity in the brain during surgeries involving the forehead.

Sevoflurane has been found to increase apoptosis and pathologic markers associated with Alzheimer disease, provoking concern over their potential contribution to postoperative cognitive dysfunction. This study aimed to determine the effects of sevoflurane on contextual fear memory of aged rats and to characterize local population connectivity of local field potentials (LFPs) in medial prefrontal cortex (mPFC) of aged rats during contextual fear memory. Eighteen-month-old male SD rats were implanted with one multichannel electrode array in mPFC. The aged rats were divided into control group, sevoflurane group (1 MAC sevoflurane for 2 h) and surgical group with 1.0 MAC sevoflurane for 2 h. We then assessed the effect of the anesthesia on contextual fear memory, and alterations in the local population connectivity of mPFC LFP networks by partial directed coherence (PDC). Surgery impaired contextual fear memory and reduced local population connectivity of mPFC LFP networks in aged rats at day 1 after the surgery and anesthesia. 1 MAC Sevoflurane anesthesia induced neither contextual fear memory impairment nor alterations in local population connectivity of mPFC LFP networks in aged rats when tested 1, 7, 15 and 30 days after exposure (P > 0.05). PDC values of theta band mPFC LFPs became strongly increased during contextual fear memory at 1, 7, 15, and 30 days after anesthesia. Our results suggest that 1 MAC sevoflurane anesthesia does not induce contextual fear memory impairment in aged rats and suggest that the increased local population connectivity in theta bands LFPs of mPFC plays a role in contextual fear memory.

Purpose Emergence agitation (EA) is common after sevoflurane anesthesia, but there are no definite predictors. This study investigated whether intraoperative electroencephalography (EEG) can indicate the occurrence of EA in children. Design A prospective predictive study design was used. Methods EEG-derived parameters (spectral edge frequency 95, beta, alpha, theta, and delta power) were measured at 1.0 minimum alveolar concentration (MAC) and 0.3 MAC of end-tidal sevoflurane (EtSEVO) in 29 patients. EA was evaluated using an EA score (EAS) in the postanesthetic care unit on arrival (EAS 0) and at 15 and 30 minutes after arrival (EAS 15 and EAS 30). The correlation between EEG-derived parameters and EAS was analyzed using Spearman correlation, and receiver-operating characteristic curve analysis was used to measure the predictability. Findings EA occurred in 11 patients. The alpha power at 1.0 MAC of EtSEVO was correlated with EAS 15 and EAS 30. The theta/alpha ratio at 0.3 MAC of EtSEVO was correlated with EAS 30. The area under the receiver-operating characteristic curve of percentage of alpha bands at 0.3 MAC of EtSEVO and the occurrence of EA was 0.672. Conclusions Children showing high-alpha powers and low theta powers (= low theta/alpha ratio) during emergence from sevoflurane anesthesia are at high risk of EA in the postanesthetic care unit.

Background: An unresolved question is the time required for the ability to return to complex tasks following anesthesia. Objectives: This study aims to characterize the severity and duration of cognitive impairment following sevoflurane or desfluane anesthesia after brief surgery using tests of cognitive ability to objectively testing performance. Patients and Methods: This study is a double blinded randomized controlled trial. Patients were randomized to receive either a desflurane or sevoflurane-based anesthetic. On the morning of the surgery the subjects performed baseline cognitive task tests (Mini Mental Status exam, Trail Making Test Part A and B, Digit Symbol Coding, Hopkins Verbal Learning Test, Stroop Color and Word Test to determine baseline cognitive function. Cognitive testing was repeated 30 minutes and 1 hour after surgery whereas Modified Telephone Interview for Cognitive Status (TICS-M) and Memory Aging Telephone Screen (MATS) was used on the following day of surgery. Results: Trail Making Test Part B cognitive test showed statistically significant in comparison for pre and post exposure of anesthetics. This difference was seen in the desflurane group. Other cognitive tests did not show differences on exposure to the anesthetic gases. Conclusions: This study questioned the difference between volatile anesthetic agent’s effects on patients completing a battery of neurocognitive tests attempting to answer if one agent has a more profound effect. Our study shows no statistically significant cognitive decline except for those in the Trail Making Part B in the Desflurane group. This conclusion is limited by the inherent limitations of the study, but does reinforce that the systemic inflammatory response from the surgery contributes cognitive impairment.

Study objective Postoperative delirium (POD) is a common complication of anesthesia. The incidence of POD in elderly patients ranges from 37% to 53%, and POD increases the morbidity and mortality of elderly patients. However, the effects of anesthetics on POD are not well known. The present study aimed to compare the incidence of POD resulting from propofol and sevoflurane anesthesia. Design Double-blind prospective study. Setting Operating room and postoperative recovery area. Patients Thirty patients in the sevoflurane anesthesia group and 29 in the propofol anesthesia group. Measurements Statistical analyses were performed using Microsoft Excel 2010 for Windows 7 (Microsoft Corporation, Redmond, Wash). Statistical analysis was performed using Fisher exact test and Student t test. Main Results The incidence of POD in the propofol anesthesia (6.9%) was significantly less than that observed in the sevoflurane anesthesia (26.7%; 038). Conclusion In comparison with sevoflurane anesthesia, propofol anesthesia is associated with a lower incidence of POD in elderly patients.

Medical Technologies National Conference (TIPTEKNO) -- OCT 15-18, 2015 -- -- Bodrum, TURKEY, WOS: 000380505200036, The main subject in this study is to monitor the changes of EEG power spectrum during sevoflurane general anesthesia and to determine the variables which show meaningful changes for anesthetic depth. Sevoflurane has been suggested as a suitable agent for anesthetic induction. The data base was constructed of the records from a total of 25 patients. During the operation blood pressure, heart rate and sevoflurane agent ratio were recorded. Additionally, EEG recordings are taken continuously during the operation. The power spectral density values corresponding 1-50 Hz frequency interval of the selected EEG slices which has 10 seconds of time interval is used. Investigated EEG parameters show correlations with anesthetic depth in sevoflurane anesthesia. This study confirms EEG power spectrum as potantially useful measures of anesthetic depth in sevoflurane anesthesia. After the induction of sevoflurane, power spectrum of EEG is changed sharply. Total power and low frequency powers are increased sharply. But the beta and gamma band frequencies are decreased totally.

Background New software was used during a pilot study of nonlinear changes in the electroencephalogram during emergence from sevoflurane anesthesia. Methods Digitized electroencephalographic signals were recorded from bipolar forehead electrodes between 1.2 and 40 k s/sec. Trajectories derived from underlying attractors were displayed continuously, and attractor dimensions were estimated. Observations are reported from 13 patients emerging from sevoflurane anesthesia. Results Qualitative observations and quantitative analysis of the data demonstrated four dynamical stages during emergence from deep anesthesia to consciousness. Conclusions The dynamical stages of emergence from sevoflurane anesthesia into consciousness demonstrate a classic route toward chaos, but the presence of chaos in the conscious state remains unproven. These stages are apparent both pictorially and analytically. Pre-emergent attractor patterns are usually distinctive; their real-time display could be a useful adjunct to depth of anesthesia monitors because they may provide warning of an imminent return to consciousness.

Our purpose was to investigate the effect of omission of fentanyl during sevoflurane anesthesia on the incidences of postoperative nausea and vomiting and on postanesthesia recovery in female patients undergoing major breast cancer surgery.Female patients (American Society of Anesthesiologists [ASA] physical status [PS] class I-II; age, 28-84 years) undergoing major breast cancer surgery were randomized to one of two anesthesia maintenance groups: sevoflurane-fentanyl anesthesia (SF; n = 25) or fentanyl-free sevoflurane anesthesia (S; n = 26). All patients were administered with propofol 2 mg x kg(-1) intravenously for anesthesia induction, a laryngeal mask airway was placed, and they received rectal diclofenac and local infiltration anesthesia. Anesthesia was maintained with sevoflurane in oxygen-air and they breathed spontaneously. The patients in group SF received fentanyl 0.1 mg intravenously and those in group S received normal saline during anesthesia.Group SF revealed higher incidences of postoperative nausea (68% vs 27%) and vomiting (32% vs 8%) in the first 24 postoperative hours than group S. The median (25th-75th percentile) length of time from postanesthesia care unit (PACU) admission to ambulation was significantly longer in group SF (n = 23) at 195 min (158-219 min), than in group S, at 141 min (101-175 min). Two patients in group SF could not walk during the PACU stay.Omission of fentanyl during sevoflurane anesthesia, combined with diclofenac and local infiltration anesthesia, decreases the incidences of postoperative nausea and vomiting and accelerates postanesthesia recovery in patients undergoing major breast cancer surgery.

Anesthetic and cardiopulmonary effects of butorphanol administered pre- versus postoperatively were determined and compared in 11 adult Hispaniolan Amazon parrots (Amazona ventralis) anesthetized with sevoflurane and subjected to coelomic endoscopy for gonadal evaluation. Birds were randomly assigned to receive butorphanol tartrate (2 mg/kg IM) either 20 minutes before induction of anesthesia with sevoflurane (B-S group) or immediately after sevoflurane anesthesia (S group). No differences in induction or recovery times were seen between groups. Heart rates of birds in the B-S group were significantly higher at 30 minutes compared with baseline and with heart rates of birds in the S group. Birds in the S group had significantly lower heart rates at both 15 and 25 minutes compared with baseline values. Respiratory rates throughout the study were significantly lower in both groups compared with baseline values. Birds in the B-S group had significantly lower respiratory rates at baseline and after 1...

Spectral entropy is a new electroencephalogram (EEG)-derived parameter that may be used to model the pharmacokinetic-pharmacodynamic (PKPD) effects of general anesthetics. In the present study we sought to derive a PKPD model of the relationship between sevoflurane concentration and spectral entropy of the EEG. We collected spectral entropy data during increasing and decreasing sevoflurane anesthesia from 20 patients. The first cycle consisted of induction and lightening phases with no supplemental medications. An effect-site compartment and inhibitory E(max) model described the relation between sevoflurane concentration and spectral entropy. PKPD parameters were derived from the full cycle and separately from the increasing and decreasing stages. The second anesthetic cycle consisted of a redeepening phase only and included airway manipulation and routinely administered adjunctives. PKPD data obtained from the first cycle were used to predict second cycle entropy changes. There was a consistent relationship between effect-site sevoflurane concentration and spectral entropy (median absolute weighted residual = 11.6%). For complete first-cycle response entropy (mean +/- sd): T1/2 K(eo) = 2.4 +/- 1.5 min, gamma = 5.9 +/- 2.3, EC50 = 1.7 +/- 0.3. We found significant differences between gamma values when the sevoflurane concentration was increasing (61.1 +/- 55.2) compared with the decreasing part of the cycle (5.7 +/- 2.8). Above an effect-site concentration of 3%, spectral entropy of the EEG is unresponsive to further increases in sevoflurane concentration. The effect-compartment inhibitory E(max) model accurately describes the relation between sevoflurane concentration and spectral entropy of the EEG. Spectral entropy decreases with increasing sevoflurane concentrations up to 3%. The steepness of the dose-response curve varies between phases of increasing and decreasing anesthetic concentrations.

Various criteria for weaning patients from ventilators in intensive care have been widely published. These criteria are increasingly incorporated into guidelines, protocols, and more recently, care pathways. We present a case where a patient's lungs were ventilated for 4 days with an infective exacerbation of chronic obstructive pulmonary disease (COPD). We successfully weaned off mechanical ventilation and rapidly extubated the patient's trachea utilizing deep sevoflurane anesthesia. Published weaning indices suggest that this would have been an inappropriate course of action at the time. However, our patient clearly benefited and avoided the need for tracheostomy and prolonged ventilation.

To determine the effect of chronic magnesium (Mg2+) deficiency on the relative arrhythmogenicity of halothane and sevoflurane in the rat.Prospective, randomized, nonblinded study.University laboratory.Male Sprague-Dawley rats (n = 48).Rats were maintained on a Mg2+-deficient or control diet for 14 days, at which time they were anesthetized with halothane or sevoflurane, a tracheostomy was performed, and the lungs were ventilated to maintain normocapnia. Catheters were inserted into a femoral vein and carotid artery. Lead II of the electrocardiogram was monitored to determine the threshold for epinephrine-induced arrhythmias.Chronic Mg2+ deficiency significantly decreased the dose of epinephrine required for arrhythmias (ADE). The reduction in the ADE was approximately one third during halothane anesthesia (p0.05) and one fifth during sevoflurane anesthesia (p0.001). Infusion of magnesium sulphate completely reversed the reduction in ADE. In normomagnesemic rats, the halothane ADE was significantly less than the sevoflurane ADE (mean difference = 6.0 microg/kg, 95% confidence interval of the difference = 3.6 to 8.4 microg/kg) (p0.005). Mg2+ deficiency significantly attenuated the difference between the halothane ADE and the sevoflurane ADE (mean difference in the Mg2+-deficient group = 0.6 microg/kg, 95% confidence interval of the difference = -0.2 to 1.5 microg/kg).Chronic Mg2+ deficiency decreased the threshold for epinephrine-induced arrhythmias and attenuated differences between the arrhythmogenic potential of halothane and sevoflurane, suggesting that arrhythmias are as likely to develop with sevoflurane as with halothane in the presence of coexisting magnesium deficiency and elevated catecholamines.

In this study, we compared postoperative liver function in patients with liver cirrhosis between isoflurane and sevoflurane anesthesia with nitrous oxide (N(2)O) and epidural block. Forty cirrhotic patients with Child-Pugh Grade A, aged 40 to 70 yr, scheduled for liver segmentectomy, had anesthesia induced with midazolam 0.1 mg/kg and fentanyl 4 micro g/kg. For maintenance, intermittent epidural administration of 1.5% lidocaine 4 to 6 mL and sevoflurane (sevoflurane group) or isoflurane (isoflurane group) with N(2)O 3 L/min in oxygen 3 L/min was used. Aspartate aminotransferase, alanine aminotransferase, total bilirubin, alkaline phosphatase, choline esterase, albumin, prothrombin time, and platelet count were measured before and 1, 3, and 7 days after surgery. Aspartate aminotransferase, alanine aminotransferase, and alkaline phosphatase increased significantly, with the peaks at 3 days after surgery in both groups. The increases in these variables were significantly larger in the isoflurane group than those in the sevoflurane group. No patient developed hepatic failure. All increases in liver enzymes were small and of questionable clinical relevance. Whether sevoflurane might be a better anesthetic when combined with N(2)O and epidural block for cirrhotic patients than isoflurane with respect to liver damage remains to be determined.In cirrhotic patients with Child-Pugh Grade A, isoflurane induced more of an increase in serum concentrations of liver enzymes after surgery than sevoflurane when combined with nitrous oxide and epidural block. However, the increases were small, and there was no clinical liver damage.

Sevoflurane anesthesia in young children has been associated with an increased incidence of emergence agitation compared with halothane. Postoperative pain may be an etiologic factor. We designed a study to compare the incidence of emergence agitation after halothane and sevoflurane anesthesia in children whose pain was managed with caudal analgesia. Eighty children undergoing inguinal hernia repair between the ages of 12 mo and 6 yr were randomly assigned to receive either halothane or sevoflurane anesthesia. Baseline preoperative anxiety was assessed with the Yale Preoperative Anxiety Scale. The children were sedated with oral midazolam, underwent a mask induction, and had a caudal block placed for postoperative analgesia. After surgery, the children's behavior was assessed with a four-point agitation scale. At 5 min after arrival in the postanesthesia care unit (PACU), sevoflurane was associated with a greater incidence of emergence agitation than halothane (26% vs 6%; P0.05), but not during the remainder of the PACU stay. Higher levels of preoperative anxiety were associated with difficult mask induction, agitation on admission to the PACU, and more severe agitation episodes. Emergence agitation appears to be an early and transient phenomenon after sevoflurane anesthesia in children with effective postoperative analgesia.Effective postoperative analgesia may reduce the incidence of emergence agitation reported with sevoflurane anesthesia. The Yale Preoperative Anxiety Scale appears to be helpful in identifying young children who are at risk for developing emergence agitation.

Emergence agitation is a common side effect of sevoflurane anesthesia in children. Dexmedetomidine, because of its sedative and analgesic properties, might be useful for the management of this adverse effect. We studied the effect of dexmedetomidine on recovery characteristics in 90 children aged 1 to 10 yr scheduled to undergo superficial lower abdominal and genital surgery. After inhaled induction with sevoflurane, patients were randomly assigned to receive saline (Group 1, n = 30), dexmedetomidine 0.15 micro g/kg (Group 2, n = 30), or dexmedetomidine 0.30 micro g/kg (Group 3, n = 30). After a laryngeal mask airway insertion a caudal block was performed in all patients. Maintenance of anesthesia was with 1% end-tidal sevoflurane and 50% nitrous oxide and spontaneous ventilation. Intraoperative hemodynamic and respiratory variables were recorded every 5 min. At the end of anesthesia time to eyes opening (TEO) and characteristics of emergence were recorded. General and intraoperative variables were similar in the 3 groups. The TEO was 7.5 +/- 5.0 min in Group 1, 8.2 +/- 5.0 min in Group 2, and 9.8 +/- 4.0 min in Group 3 (NS). The incidence (95% confidence interval) of agitation was 37% (20%-54%) in Group 1, 17% (4%-30%) in Group 2, and 10% (0%-21%) in Group 3 (P0.05). Paired comparisons showed a significant difference for Group 1 versus Group 3 (P0.05, 95% confidence interval of the difference: 7%-47%). The time to discharge from the postanesthesia care unit was similar for the 3 groups. We conclude that a dose of dexmedetomidine 0.3 micro g/kg administered after induction of anesthesia reduces the postsevoflurane agitation in children and with no adverse effects.In children undergoing surgery using sevoflurane anesthesia, dexmedetomidine 0.3 micro g/kg administered in 10 min after induction reduced the incidence of emergence agitation from 37% in the control group to 10%. No adverse effects attributable to dexmedetomidine were observed.

Background The spinal H-reflex has been shown to correlate with surgical immobility, i.e., the absence of motor responses to noxious stimulation, during isoflurane anesthesia. Here, the authors established individual concentration-response functions for H-reflex amplitude and tested the predictive power of the H-reflex for movement responses during sevoflurane anesthesia in comparison to electroencephalographic parameters. In addition, they investigated the effect of noxious stimulation on the H-reflex itself. Methods The authors studied 12 female patients during sevoflurane anesthesia before surgery. The sevoflurane concentration was increased, a laryngeal mask was inserted, and then the sevoflurane concentration was decreased until H-reflex amplitude (recorded over the soleus muscle) recovered. Thereafter, the end-tidal sevoflurane concentration was kept at a constant value close to the minimum alveolar concentration for suppression of movement responses after tetanic stimulation (MACtetanus), determined by the Dixon up-down method. Pharmacodynamic modeling of H-reflex amplitude and of the Bispectral Index was performed, and predictive values for motor responses to noxious electrical stimulation (50 Hz, 60 mA tetanus, volar forearm) were compared using the prediction probability. Results Concentration-dependent depression of H-reflex amplitude by sevoflurane was well modeled (median r2 = 0.97) by a sigmoid function with a median EC50 of 1.5 vol% and a median slope parameter of 3.7, much steeper than the slope for the Bispectral Index. MACtetanus calculated by logistic regression was 1.6 vol%. H-reflex amplitude predicted motor responses to noxious stimulation with a prediction probability of 0.76, whereas the prediction probability for Bispectral Index and spectral edge frequency (SEF95) were not different from chance alone. Noxious stimulation was followed by a substantial increase of H-reflex amplitude for several minutes, whereas the Bispectral Index and SEF95 exhibited no significant changes. Conclusions Suppression of movement to noxious stimulation and suppression of H-reflex amplitude by sevoflurane follow similar concentration-response functions. Although this does not imply a causal relation, it explains the high predictive value of H-reflex amplitude for motor responses to noxious stimuli, even in a narrow concentration range around the MACtetanus.

The effects of volatile anesthetics on change in the bispectral index (BIS) due to tracheal intubation are unclear. We investigated hemodynamic and BIS responses to intubation during isoflurane or sevoflurane anesthesia.After obtaining Institutional Review Board approval and informed consent, we randomly allocated 40 patients of American Society of Anesthesiologists (ASA) physical status I to receive either isoflurane (ISO group; n = 20) or sevoflurane (SEV group; n = 20). The patients were anesthetized with thiamylal and were ventilated with 100% oxygen, using a mask. The inspired concentrations of isoflurane and sevoflurane were gradually increased and maintained at end-tidal anesthetic concentrations of 2 minimum alveolar concentration (MAC) during the study period. Tracheal intubation was performed 15 min after the end-tidal anesthetic concentrations had reached 2 MAC. Mean arterial pressure (MAP), heart rate (HR), and BIS were recorded before induction, at the loss of consciousness, before laryngoscopy, and at 1, 3, and 5 min after intubation.Anesthesia with 2 MAC volatile anesthetics increased HR in the ISO group, and decreased MAP in the SEV group. The BIS value decreased from 95 +/- 3 and 96 +/- 2 before thiamylal to 39 +/- 9 and 38 +/- 10 before intubation in the ISO and SEV groups, respectively. MAP and HR were significantly increased in both groups 1 and 3 min after intubation, but BIS remained unchanged.Anesthesia with 2 MAC of isoflurane and sevoflurane was effective to suppress the change in BIS due to intubation but was not sufficient to prevent changes in hemodynamic responses.

Objective—To characterize halothane and sevoflurane anesthesia in spontaneously breathing rats. Animals—16 healthy male Sprague-Dawley rats. Procedure—8 rats were anesthetized with halothane and 8 with sevoflurane. Minimum alveolar concentration (MAC) was determined. Variables were recorded at anesthetic concentrations of 0.8, 1.0, 1.25, and 1.5 times the MAC of halothane and 1.0, 1.25, 1.5, and 1.75 times the MAC of sevoflurane. Results—Mean (± SEM) MAC for halothane was 1.02 ± 0.02% and for sevoflurane was 2.99 ± 0.19%. As sevoflurane dose increased from 1.0 to 1.75 MAC, mean arterial pressure (MAP) decreased from 103.1 ± 5.3 to 67.9 ± 4.6 mm Hg, and PaCO2 increased from 58.8 ± 3.1 to 92.2 ± 9.2 mm Hg. As halothane dose increased from 0.8 to 1.5 MAC, MAP decreased from 99 ± 6.2 to 69.8 ± 4.5 mm Hg, and PaCO2 increased from 59.1 ± 2.1 to 75.9 ± 5.2 mm Hg. Respiratory rate decreased in a dose-dependent fashion from 88.5 ± 4.5 to 58.5 ± 2.7 breaths/min during halothane anesthesia and from 42.3 ± 1.8 to 30.5 ± 4.5 breaths/min during sevoflurane anesthesia. Both groups of rats had an increase in eyelid and pupillary aperture with an increase in anesthetic dose. Conclusions and Clinical Relevance—An increase in PaCO2 and a decrease in MAP are clinical indicators of an increasing halothane and sevoflurane dose in unstimulated spontaneously breathing rats. Increases in eyelid aperture and pupil diameter are reliable signs of increasing depth of halothane and sevoflurane anesthesia. Decreasing respiratory rate is a clinical indicator of an increasing dose of halothane. (Am J Vet Res 2003;64:470–474)

Sevoflurane is a volatile anesthetic commonly used for the induction and maintenance of anesthesia. We present the case of a 34-year-old woman in whom generalized periodic epileptiform discharges developed during induction of anesthesia with sevoflurane. Although sevoflurane anesthesia can be associated with the development of epileptiform discharges, the clinical relevance of this is unclear.

Aim: To evaluate the mean changes in corneal endothelial cells in eyes that operated under sevoflurane general anesthesia.

Various researchers studied the nephrotoxicity of inhalational anesthetics, with contradictory results. We aimed to observe the impact of the repeated isoflurane or sevoflurane anesthesia on kidney structure and function. 40 female rats were used in this study. Animals were divided in 8 groups. Two groups served as control: IM (isoflurane) and SM (sevoflurane), exposed to oxygen alone (1l/min) 3 times, for 2 hours, every other day. Three groups were anesthetized with isoflurane (I1, I2, I3) and the other three (S1, S2, S3) with sevoflurane. The anesthetics were administered three times, for two hours long each, every other day. Rats were sacrificed through cervical dislocation as follows: groups IM, SM, I1, S1 imediately after the last anesthesia, groups I2, S2 – 6 hours post-anesthesia and groups I3, S3 – 24 hours post-anesthesia. Kidney samples were harvested, fixed in 10% buffered formaline, embedded in paraffin, sectioned (5 µm thickness) and stained with Goldner’s trichrome metod. After isoflurane anesthesia, the kidney displays a moderate congestion in the corticomedullary area, which maintains throughout the experimental period. The only changes in animals anesthetized with sevoflurane also appear on the vascular component. The congestion maintains throughout the experimental period in the renal cortex, as well as the corticomedullary area. No other aspects that suggest functional impairment are observed, in any of the experimental groups. Inhalational anesthesia with isoflurane and sevoflurane produces a moderate congestion, without majorly impairing the kidney function.

Depth of anesthesia estimation with the Electroencephalogram (EEG) is a main current challenge in anesthesia studies. This paper proposes an original method founded on combination of permutation entropy and frequency measure to calculate an index, called Brain function index (BFI), to quantify depth of anesthesia. As EEG derived features characterize different aspects of EEG signal, it would be logical to utilize multiple features to evaluate the effect of anesthetic. Such a method implemented in the Saadat brain function assessment module (Saadat Co., Tehran, Iran). The BFI and commercial RE index as employed in the Datex-Ohmeda monitor are applied to EEG signals gathered from 18 patients during sevoflurane anesthesia. The results show that both BFI and RE indices track the changes in EEG especially at deep anesthesia state. However, the BFI index makes better response about the point of loss of consciousness and it can be derived with significantly less computational complexity. Taking into account the high accuracy of this method, an innovative EEG processing device may be extended to help the anesthetists to estimate the depth of anesthesia precisely.

(WT) mice (n1⁄48) were studied at 17-19 months-of-age. Whole brain perfusion images (360 mm isotropic spatial resolution) were acquired with a multi-slice, pseudocontinuous ASL pulse sequence on a 7T animal MRI system. Mice were scanned both in the awake state and under sevoflurane anesthesia (a known vasodilator) to assess group differences in resting CBF and vasodilatory response, respectively. The perfusion images were co-registered to anatomical MR images acquired during the same session, and spatially normalized to reference coordinate space to generate regional perfusion measures using a fully-automated image processing pipeline (NIGHTWING TM, Biospective Inc.). Results: The Tg mice exhibited a lower resting CBF (w15%) compared to theWTmice in most brain regions. Under sevoflurane, this difference increased tow30% as the Tgmice exhibited an attenuated vasodilatory response relative to the WT group. The coefficient of variation was higher in the awake mice. Conclusions: This study demonstrated that APPoverexpressing Tg mice have impaired resting cerebrovascular function, which is exacerbated under a challenge condition. The greater effect size of the challenge state suggests that utilization of an appropriate vasodilatory challenge could be a useful paradigm in human AD studies.

Objective—To determine the safety, efficacy, and effects on hemolymph gas analysis variables of sevoflurane anesthesia in Chilean rose tarantulas (Grammostola rosea). Animals—12 subadult Chilean rose tarantulas of unknown sex. Procedures—Spiders were anesthetized in a custom chamber with sevoflurane (5% in oxygen [1.0 L/min]), then allowed to recover in 100% oxygen. Righting reflex was evaluated every 3 minutes during anesthesia to determine time to anesthetic induction and recovery. Hemolymph samples were collected from an intracardiac location prior to and after induction of anesthesia and evaluated to determine various gas analysis variables. Results—Mean ± SD induction and recovery times were 16 ± 5.91 minutes and 29 ± 21.34 minutes, respectively. Significant differences were detected for Po2, base excess, and glucose and ionized magnesium concentrations between hemolymph samples obtained before anesthesia and those obtained after induction of anesthesia. Conclusions and Clinical Relevance—Results of this study suggested that the use of sevoflurane as an anesthetic agent for Chilean rose tarantulas was safe and effective. Various hemolymph sample gas analysis values changed during anesthesia.

Background/aim: There are limited data in the literature investigating the effects of anesthetic agents on cardiac output used in the chest-knee position. Te aim of this study is to compare the effects of inhalation and total intravenous anesthesia on cardiac output in patients undergoing lumbar discectomy in the chest-knee position. Materials and methods: Forty patients undergoing discectomy in the chest-knee position were allocated to 2 groups. The first group (GrS, n = 20) received sevofurane after thiopental induction, while the second group (GrP, n = 20) received propofol induction and infusion. Heart rate (HR), mean arterial pressure (MAP), peripheral oxygen saturation, cardiac output (CO), and cardiac index (CI) were recorded. Results: Groups were comparable in terms of HR and MAP. The differences related to anesthetic technique and position were statistically significant within each group. Cardiac output and CI were similar between the groups. Cardiac output and CI of GrP were found to be decreased in the chest-knee position and significantly elevated in the supine position after surgery (P < 0.05). There were significant decreases in the mean CO and CI values recorded after the chest-knee position in GrP. Conclusion: Sevofurane is found to be superior when compared to propofol in patients undergoing surgery in the chest-knee position in terms of perioperative hemodynamic stability. Therefore, sevofurane may be the anesthetic of choice, especially in patients operated on in the chest-knee position with suspected hemodynamic instability. © TÜBİTAK.

Background Hypocapnia induced following the accidental intravenous infusion of a local anesthetic can mitigate anesthetic toxicity, but the effects of hypocapnia induced prior to local anesthetic infusion are unknown. In this study, we examined the effects of prior hypocapnia on bupivacaine-induced cardiotoxicity in rats. Methods Eighteen Sprague–Dawley rats were randomly divided into two groups: one receiving sevoflurane with normal ventilation (Control Group) and the other receiving sevoflurane with hyperventilation to induce hypocapnia (Hypocapnia Group). After 30 min, both groups received continuous intravenous infusions of 0.25% bupivacaine at 2 mg · kg−1 · min−1. The time taken to reach 25% and 50% reductions in heart rate (HR; HR-25%, HR-50%) and mean arterial pressure (MAP; MAP-25%, MAP-50%) from the start of bupivacaine infusion were recorded. The difference between HR-25% and MAP-25% was calculated. The times of the first ventricular premature beat (VPB) and final systole were also recorded. Results In the Hypocapnia Group, HR-50%, MAP-25%, and MAP-50% were prolonged compared with the Control Group (P P Conclusion In rats under sevoflurane anesthesia, prior hypocapnia delayed the onset of bupivacaine-induced cardiotoxicity. Prior hypocapnia should be avoided during continuous bupivacaine nerve block under general anesthesia, because it may delay the detection of cardiotoxicity.

Incidence of PONV in Maxillofacial Surgery: Comparison of High-Flow and Low-Flow Anesthesia Postoperative Nausea and Vomiting (PONV) still remains the “big little challenge” for anesthesiologists in their everyday practice. The aim of this study was to compare the incidence and severity of PONV, antiemetic requirement and patient satisfaction, after high-flow versus low-flow sevoflurane anesthesia without antiemetic prophylaxis.