UPLC-MS/MS Method for Detection of Etomidate and Its Metabolite Etomidate Acid Quantity in Blood / 法医学杂志

OBJECTIVES@#To establish a method for the simultaneous quantitative analysis of etomidate and its metabolite etomidate acid in blood, and to discuss its application value in actual cases.@*METHODS@#Acetonitrile precipitate protein method was used, and C18 column was selected. Gradient elution was performed with acetonitrile and 5 mmol/L ammonium acetate within 6 min. Electrospray ionization source in positive ion mode was used. The internal standard etomidate acid-d5 was obtained by etomidate-d5 alkaline hydrolysis reaction. Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used for quantitative analysis. The methodological verification was conducted.@*RESULTS@#Etomidate and etomidate acid in blood showed good linear relationship in the quantitative linear range (r>0.999), with the lower limit of quantification was 2.5 ng/mL and 7.5 ng/mL, respectively. The accuracy, precision, recovery rate, and matrix effect of the method met the professional verification standards. The practical application results showed that etomidate and etomidate acid could be detected in the blood of the abusers, and their mass concentrations ranged from 17.24 to 379.93 ng/mL.@*CONCLUSIONS@#The method established in this study can simultaneously quantify etomidate and etomidate acid in blood, which is simple and convenient to operate with accuracy. It can meet the detection needs of actual cases and provide technical support for law enforcement to crack down on etomidate abuse.

Effect of etomidate on the reuniens neuronal activity / 中南大学学报(医学版)

OBJECTIVES@#To explore the effect of etomidate on the neuronal activity of ventral thalamic reuniens nucleus and the underlying mechanisms.@*METHODS@#Whole-cell patch clamp method was used to explore the effect of etomidate on the activity of ventral thalamic reuniens neurons in the acute brain slices obtained from 4-5 weeks old C57BL/6J mice. The electrophysiological characteristics of ventral thalamic reuniens neurons were recorded in the current clamp mode, and then the effects of etomidate (0.5, 2.0, 8.0 μmol/L etomidate groups) and intralipid (intralipid group) on the discharge frequency and membrane potential of ventral thalamic reuniens neurons were recorded. During the experiment, the ventral thalamic reuniens neuron firing rates (RNFRs) were recorded as F@*RESULTS@#In the intralipid group, there was no significant difference among the F@*CONCLUSIONS@#Etomidate can inhibit the activity of ventral thalamic reuniens neurons in concentration-dependent manner, and which is reversible. Etomidate with sub-anesthetic concentration inhibits the activity of ventral thalamic reuniens neurons via targeting the GABA

Etomidate reduces excitability of the neurons and suppresses the function of nAChR ventral horn in the spinal cord of neonatal rats / 南方医科大学学报

OBJECTIVE@#To investigate the effects of etomidate on electrophysiological properties and nicotinic acetylcholine receptors (nAChRs) of ventral horn neurons in the spinal cord.@*METHODS@#The spinal cord containing lumbosacral enlargement was isolated from 19 neonatal SD rats aged 7-12 days. The spinal cord were sliced and digested with papain (0.18 g/30 mL artificial cerebrospinal fluid) and incubated for 40 min. At the ventral horn, acute mechanical separation of neurons was performed with fire-polished Pasteur pipettes, and perforated patch-clamp recordings combined with pharmacological methods were employed on the adherent healthy neurons. In current-clamp mode, the spontaneous action potential (AP) of the ventral horn neurons in the spinal cord was recorded. The effects of pretreatment with different concentrations of etomidate on AP recorded in the ventral horn neurons were examined. In the voltage-clamp mode, nicotine was applied to induce inward currents in the ventral horn neurons, and the effect of pretreatment with etomidate on the inward currents induced by nicotine were examined with different etomidate concentrations, different holding potentials and different use time.@*RESULTS@#The isolated ventral horn neurons were in good condition with large diverse somata and intact processes. The isolated spinal ventral horn neurons (=21) had spontaneous action potentials, and were continuously perfused for 2 min with 0.3, 3.0 and 30.0 μmol/L etomidate. Compared with those before administration, the AP amplitude, spike potential amplitude and overshoot were concentration-dependently suppressed ( < 0.01), and spontaneous discharge frequency was obviously reduced ( < 0.01, =12). The APs of the other 9 neurons were completely abolished by etomidate at 3.0 or 30 μmol/L. At the same holding potential (VH=-70 mV), pretreatment with 0.3, 3.0 or 30.0 μmol/L etomidate for 2 min concentration-dependently suppressed the current amplitude induced by 0.4 mmol/L nicotine ( < 0.01, =7). At the holding potentials of - 30, - 50, and - 70 mV, pretreatment with 30.0 μmol/L etomidate for 2 min voltage-dependently suppressed the current amplitude induced by 0.4 mmol/L nicotine ( < 0.01, =6 for each holding potential). During the 6 min of 30.0 μmol/L etomidate pretreatment, the clamped cells were exposed to 0.4 mmol/L nicotine for 4 times at 0, 2, 4, and 6 min (each exposure time was 2 s), and the nicotinic current amplitude decreased gradually as the number of exposures increased. But at the same concentration, two nicotine exposures (one at the beginning and the other at the end of the 6 min pretreatment) resulted in a significantly lower inhibition rate compared with 4 nicotine exposures ( < 0.01, =6).@*CONCLUSIONS@#etomidate reduces the excitability of the spinal ventral neurons in a concentration-dependent manner and suppresses the function of nAChR in a concentration-, voltage-, and use-dependent manner.

Easy sedation anesthesia guide for non-anesthetic medical personnel

Currently, sedation anesthesia is increasingly used in many medical fields, from gastroscopy to medical imaging. The demand for sedation anesthesia is expected to increase gradually with increasing number of day surgeries and increased expectations from medical services. The demand for sedation anesthesia is considerably higher than the available pool of anesthesiologists; therefore, in a significant number of cases, sedation anesthesia is induced by non-anesthesiologists. However, there is no systematic provision of education or expertise for non-anesthesiologists in delivering sedation anesthesia. In cases of non-anesthesiologists inducing anesthesia, social controversy is often caused by medical accidents and substance abuse. In this review, I have briefly summarized what non-anesthesiologists should know about sedation anesthesia and have presented guidelines simplifying sedation anesthesia for non-anesthesia medical personnel.

Using Etomidate and Midazolam for Screening Colonoscopies Results in More Stable Hemodynamic Responses in Patients of All Ages

BACKGROUND/AIMS: Recent studies have demonstrated that etomidate is a safe sedative drug with noninferior sedative effects. In our recent study, we revealed that etomidate/midazolam was more hemodynamically stable than propofol/midazolam in elderly patients undergoing colonoscopies. We aimed to investigate whether compared with propofol/midazolam, etomidate/midazolam causes fewer cardiopulmonary adverse events with noninferior efficacy for screening colonoscopies in patients of all ages. METHODS: In this single-center, randomized, double-blind study, we prospectively enrolled 200 patients. The patients were divided into etomidate and propofol groups. The primary outcome was the occurrence of cardiopulmonary adverse events. The secondary outcomes were the proportion of patients with fluctuations in vital signs (oxygen desaturation and transient hypotension), adverse events interrupting the procedure, and sedation-related outcomes. RESULTS: Adverse cardiopulmonary events were more common in the propofol group than the etomidate group (65.0% vs 51.0%, respectively; p=0.045). Forty-six patients (46.0%) in the propofol group and 29 (29.0%) in the etomidate group experienced fluctuations in their vital signs (p=0.013). The proportions of patients experiencing adverse events that interrupted the procedure, including myoclonus, were not significantly different between the two groups (etomidate: 20.0% vs propofol: 11.0%; p=0.079). Both groups had similar sedation-related outcomes. Multivariate analysis revealed that compared with the propofol groups, the etomidate group had a significantly lower risk of fluctuations in vital signs (odds ratio, 0.427; 95% confidence interval, 0.230 to 0.792; p=0.007). CONCLUSIONS: Compared with using propofol/midazolam, using etomidate/midazolam for screening colonoscopies results in more stable hemodynamic responses in patients of all ages; therefore, we recommend using etomidate/midazolam for colonoscopies in patients with cardiovascular risk factors.

Anesthetic Management for Elective Total Hip Replacement Arthoroplasty in a Patient with Eisenmenger's Syndrome

Eisenmenger's syndrome describes the elevation of pulmonary arterial pressure to the systemic level caused by an increased pulmonary vascular resistance with reversed or bi-directional shunt through an intracardiac or aortopulmonary communication. We report the case of 48-year-old woman with an elective total hip replacement arthroplasty for right femur neck fracture with Eisenmenger's syndrome secondary to large atrial septal defect. Anesthesia was induced with etomidate and rocuronium, maintained with desflurane 5 vol% and O₂ 3 L/min. Mirinone and norepinephrine were infused continuously to decrease right to left shunt. The patient was extubated after spontaneous breathing recovery and transferred to the intensive care unit. She was treated with mirinone, norepinephrine, dopamine, and dobutamine for hypoxemia and hypotension. After 3 hours of admission to intensive care unit, the patient had a cardiac arrest and died 30 minutes later.

Comparison of priming versus slow injection for reducing etomidate-induced myoclonus: a randomized controlled study / 대한마취과학회지

BACKGROUND: Etomidate injection is often associated with myoclonus. Etomidate injection technique influences the incidence of myoclonus. This study was designed to clarify which of the two injection techniques—slow injection or priming with etomidate—is more effective in reducing myoclonus. METHODS: This prospective randomized controlled study was conducted on 189 surgical patients allocated to three study groups. Control group (Group C, n = 63) received 0.3 mg/kg etomidate (induction dose) over 20 s. Priming group (Group P, n = 63) received pretreatment with 0.03 mg/kg etomidate, followed after 1 min by an etomidate induction dose over 20 s. Slow injection group (Group S, n = 63) received etomidate (2 mg/ml) induction dose over 2 min. The patients were observed for occurrence and severity of myoclonus for 3 min from the start of injection of the induction dose. RESULTS: The incidence of myoclonus in Group P (38/63 [60.3%], 95% CI: 48.0–71.5) was significantly lower than in Group C (53/63 [84.1%], 95% CI: 72.9–91.3, P = 0.003) and Group S (49/63 [77.8%], 95% CI: 66.0–86.4, P = 0.034). Myoclonus of moderate or severe grade occurred in significantly more patients in Group C (68.3%) than in Group P (36.5%, P < 0.001) and Group S (50.8%, P = 0.046), but the difference between Groups P and S was not significant (P = 0.106). CONCLUSIONS: Priming is more effective than slow injection in reducing the incidence of myoclonus, but their effects on the severity of myoclonus are comparable.

Comparison of granisetron and lidocaine on reducing injection pain of etomidate: a controlled randomized study / Comparação de granisetrona e lidocaína na redução da dor causada pela injeção de etomidato: estudo randômico e controlado

Abstract Background and objectives Reducing pain on injection of anesthetic drugs is of importance to every anesthesiologist. In this study we pursued to define if pretreatment by granisetron reduces the pain on injection of etomidate similar to lidocaine. Methods Thirty patients aged between 18 and 50 years of American Society of Anesthesiologists physical status class I or II, whom were candidates for elective laparoscopic cholecystectomy surgery were enrolled in this study. Two 20 gauge cannulas were inserted into the veins on the dorsum of both hands and 100 mL of normal saline was administered during a 10 min period from each cannula. Using an elastic band as a tourniquet, venous drainage of both hands was occluded. 2 mL of granisetron was administered into one hand and 2 mL of lidocaine 2% at the same time into the other hand. One minute later the elastic band was opened and 2 mL of etomidate was administered to each hand with equal rates. The patients were asked to give a score from 0 to 10 (0 = no pain, 10 = severe pain) to each the pain sensed in each hand. Results Two patients were deeply sedated after injection of etomidate and unable to answer any questions. The mean numerical rating score for injection pain of intravenously administered etomidate after intravenous granisetron was 2.3 ± 1.7, which was lower when compared with pain sensed due to intravenously administered etomidate after administration of lidocaine 2% (4.6 ± 1.8), p < 0.05. Conclusion The result of this study demonstrated that, granisetron reduces pain on injection of etomidate more efficiently than lidocaine.

Resumo Justificativa e objetivos A redução da dor causada pela injeção de anestésicos é importante para todos os anestesiologistas. Neste estudo buscamos definir se o pré-tratamento com granisetrona reduz a dor causada pela injeção de etomidato de forma semelhante à lidocaína. Métodos Trinta pacientes entre 18 e 50 anos, estado físico ASA I ou II (de acordo com a classificação da Sociedade Americana de Anestesiologistas) e candidatos à colecistectomia laparoscópica eletiva foram incluídos neste estudo. Duas cânulas de calibre 20 foram inseridas nas veias do dorso de ambas as mãos e 100 mL de soro fisiológico foram administrados durante 10 minutos através de cada cânula. Com um torniquete elástico, a drenagem venosa de ambas as mãos foi ocluída. Granisetrona (2 mL) foi administrado em uma das mãos e lidocaína a 2% (2 mL) na outra mão ao mesmo tempo. Após um minuto, o torniquete foi afrouxado e 2 mL de etomidato foram administrados em velocidade igual a cada uma das mãos. Solicitamos dos pacientes uma classificação de 0 a 10 para a dor sentida em cada uma das mãos (0 = sem dor, 10 = dor intensa). Resultados Dois pacientes estavam profundamente sedados após a injeção de etomidato e, portanto, incapazes de responder a qualquer pergunta. O escore médio de classificação da dor à injeção de etomidato administrado por via endovenosa após granisetrona intravenoso foi de 2,3 ± 1,7, o que foi menor em comparação com a dor sentida à administração intravenosa de etomidato após a administração de lidocaína a 2% (4,6 ± 1,8), p < 0,05. Conclusão O resultado deste estudo demonstrou que granisetrona reduz a dor causada pela injeção de etomidato com mais eficácia do que lidocaína.

Ectopic ACTH Syndrome - Experience with etomidate / Journal of the ASEAN Federation of Endocrine Societies

@#For ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS), when surgery is not feasible, or in cases of severe biochemical disturbances, immunosuppression or mental instability, medical therapy with agents such as etomidate is indicated. We present our experience in using etomidate for a 41-year old female with EAS secondary to a malignant mediastinal paraganglioma. We were able to demonstrate that etomidate can be used effectively to control severe hypercortisolism in a lower dose than previously described.

Effect of gabapentin pretreatment on myoclonus after etomidate: a randomized, double-blind, placebo-controlled study / Efeito do pré-tratamento com gabapentina sobre a mioclonia após etomidato: um estudo randômico, duplo-cego e controlado por placebo

Abstract Aim: To evaluate the effects of three different doses of gabapentin pretreatment on the incidence and severity of myoclonic movements linked to etomidate injection. Method: One hundered patients, between 18 and 60 years of age and risk category American Society of Anesthesiologists I-II, with planned elective surgery under general anesthetic were included in the study. The patients were randomly divided into four groups and 2 h before the operation were given oral capsules of placebo (Group P, n = 25), 400 mg gabapentin (Group G400, n = 25), 800 mg gabapentin (Group G800, n = 25) or 1200 mg gabapentin (Group G1200, n = 25). Side effects before the operation were recorded. After preoxygenation for anesthesia induction 0.3 mg kg−1 etomidate was administered for 10 s. A single anesthetist with no knowledge of the study medication evaluated sedation and myoclonic movements on a scale between 0 and 3. Two minutes after induction, 2 µg kg−1 fentanyl and 0.8 mg kg−1 rocuronium were administered for tracheal intubation. Results: Demographic data were similar. Incidence and severity of myoclonus in Group G1200 and Group G800 were significantly lower than in Group P; sedation incidence and level were appreciably higher compared to Group P and Group G400. While there was no difference in the incidence of myoclonus between Group P and Group G400, the severity of myoclonus in Group G400 was lower than in the placebo group. In the two-hour period before induction other than sedation none of the side effects related to gabapentin were observed in any patient. Conclusion: Pretreatment with 800 mg and 1200 mg gabapentin 2 h before the operation increased the level of sedation and reduced the incidence and severity of myoclonic movements due to etomidate.

Resumo Objetivo: Avaliar os efeitos de três doses diferentes de gabapentina como pré-tratamento sobre a incidência e a gravidade dos movimentos mioclônicos associados à injeção de etomidato. Método: Cem pacientes, entre 18-60 anos, estado físico ASA I-II, programados para cirurgia eletiva sob anestesia geral, foram incluídos no estudo. Os pacientes foram randomicamente divididos em quatro grupos e duas horas antes da operação receberam cápsulas orais de placebo (Grupo P, n = 25), 400 mg de gabapentina (Grupo G400, n = 25), 800 mg de gabapentina (Grupo G800, n = 25) e 1.200 mg de gabapentina (Grupo G1.200, n = 25). Os efeitos colaterais antes da cirurgia foram registados. Após pré-oxigenação para a indução da anestesia, etomidate (0,3 mg.kg−1) foi administrado por 10 segundos. Um único anestesista, cego para a medicação do estudo, avaliou a sedação e os movimentos mioclônicos com uma escala de 0 a 3. Dois minutos após a indução, fentanil (2 µgr.kg−1) e rocurônio (0,8 mg.kg−1) foram administrados para a intubação traqueal. Resultados: Os dados demográficos foram semelhantes. A incidência e a gravidade da mioclonia nos grupos G1.200 e G800 foram significativamente menores do que no Grupo P; a incidência e o nível de sedação foram consideravelmente maiores comparados com o Grupo P e o Grupo G400. Enquanto não houve diferença na incidência de mioclonia entre os grupos P e G400, a gravidade da mioclonia no Grupo G400 foi menor do que no grupo placebo. No período de duas horas antes da indução, nenhum dos efeitos colaterais relacionados à gabapentina, exceto sedação, foi observado em qualquer paciente. Conclusão: O pré-tratamento com 800 mg e 1.200 mg de gabapentina duas horas antes da operação aumentou o nível de sedação e reduziu a incidência e a gravidade dos movimentos mioclônicos associados ao etomidato.

A comparative study between propofol and etomidate in patients under general anesthesia / Estudo comparativo entre propofol e etomidato em pacientes sob anestesia geral

ABSTRACT BACKGROUND AND OBJECTIVES: Induction of anesthesia is a critical part of anesthesia practice. Sudden hypotension, arrhythmias, and cardiovascular collapse are threatening complications following injection of induction agent in hemodynamically unstable patients. It is desirable to use a safe agent with fewer adverse effects for this purpose. Present prospective randomized study is designed to compare propofol and etomidate for their effect on hemodynamics and various adverse effects on patients in general anesthesia. METHODS: Hundred ASA I and II patients of age group 18-60 years scheduled for elective surgical procedure under general anesthesia were randomly divided into two groups of 50 each receiving propofol (2 mg/kg) and etomidate (0.3 mg/kg) as an induction agent. Vital parameters at induction, laryngoscopy and thereafter recorded for comparison. Adverse effect viz. pain on injection, apnea and myoclonus were carefully watched. RESULTS: Demographic variables were comparable in both the groups. Patients in etomidate group showed little change in mean arterial pressure (MAP) and heart rate (HR) compared to propofol (p > 0.05) from baseline value. Pain on injection was more in propofol group while myoclonus activity was higher in etomidate group. CONCLUSIONS: This study concludes that etomidate is a better agent for induction than propofol in view of hemodynamic stability and less pain on injection.

RESUMO JUSTIFICATIVA E OBJETIVOS: A indução é uma parte crítica da prática de anestesia. Hipotensão súbita, arritmias e colapso cardiovascular são complicações ameaçadoras após a injeção de agente de indução em pacientes hemodinamicamente instáveis. É aconselhável o uso de um agente seguro com menos efeitos adversos para esse propósito. O presente estudo prospectivo, randômico, teve como objetivo comparar propofol e etomidato quanto a seus efeitos sobre a hemodinâmica e aos vários efeitos adversos em pacientes sob anestesia geral. MÉTODOS: Cem pacientes ASA I e II, entre 18-60 anos, programados para procedimento cirúrgico eletivo sob anestesia geral, foram divididos aleatoriamente em dois grupos de 50 cada para receber propofol (2 mg/kg) e etomidato (0,3 mg/kg) como um agente de indução. Os parâmetros vitais na indução, laringoscopia e posteriormente foram registrados para comparação. Efeitos adversos como dor à injeção, apneia e mioclonia foram cuidadosamente monitorados. RESULTADOS: As variáveis demográficas foram comparáveis em ambos os grupos. Os pacientes do grupo etomidato apresentaram pouca alteração da pressão arterial média (PAM) e da frequência cardíaca (FC) em comparação com o grupo propofol (p < 0,05) a partir do valor basal. Houve mais dor à injeção no grupo propofol, enquanto houve mais atividade mioclônica no grupo etomidato. CONCLUSÕES: Este estudo conclui que etomidato é um agente melhor para a indução do que o propofol em relação à estabilidade hemodinâmica e menos dor à injeção.

Meta analysis for the anesthesia effect and adverse reactions of etomidate and propofol on the painless abortion surgery / 中南大学学报(医学版)

OBJECTIVE@#To evaluate the anesthesia effect of etomidate and propofol on painless abortion surgery. 
@*METHODS@#After screening the Cochrane Library, Pubmed, China National Knowledge Infrastructure (CNKI), WANFANG, VIP database, the literatures regarding the anesthesia effect of etomidate and propofol on painless abortion surgery were collected from 1995 to 2014. The randomized controlled trials (RCTs) were selected, the quality evaluation was performed and the data was analyzed by using RevMan5.3 software.
@*RESULTS@#A total of 1 130 patients were included in 9 RCTs. The results of Meta analysis were as follows: the anesthesia induction time in the etomidate group was less than that in propofol group (MD=-0.14, 95% CI -0.24 to -0.04, P=0.004); there were more adverse reactions, such as myoclonus, nausea and vomiting, in the etomidate group compared with the propofol group (P0.05); the surgery time, analgesia and duration from withdrawal to the wake-up was not significantly different between the 2 groups (P>0.05). 
@*CONCLUSION@#Etomidate had a shorter anesthesia induction time than propofol in the painless abortion surgery. The incidence of reverse reactions such as myoclonus, nausea and vomiting, was more common in application of etomidate, whereas the incidence of injection pain was more common in the use of propofol group. There was no significant difference in respiratory depression between the 2 drugs. The comprehensive efficacy of propofol is better than etomidate.

Ectopic ACTH Syndrome – Experience with Etomidate / Journal of the ASEAN Federation of Endocrine Societies

@#For ectopic adrenocorticotropic hormone (ACTH) syndrome (EAS), when surgery is not feasible, or in cases of severe biochemical disturbances, immunosuppression or mental instability, medical therapy with agents such as etomidate is indicated. We present our experience in using etomidate for a 41-year old female with EAS secondary to a malignant mediastinal paraganglioma. We were able to demonstrate that etomidate can be used effectively to control severe hypercortisolism in a lower dose than previously described.

The effects of etomidate and midazolam on adipose tissue-derived mesenchymal stem cell proliferation / 대한마취과학회지

BACKGROUND: Stem cell therapy using adipose tissue-derived mesenchymal stem cells (ADSCs), which are capable of multipotent differentiation, is currently being investigated in the field of tissue regeneration and the treatment of patients in intensive care units. It is known that type-A γ-aminobutyric acid (GABA(A)) receptor activity has an influence on stem cell proliferation. Thus, we investigated the effects of the clinically available GABA(A) receptor agonists, etomidate and midazolam, on ADSC proliferation measured by the cell counting kit-8 assay. METHODS: ADSCs cultured in control medium or adipogenic differentiation medium for 15 days were divided into 5 treatment groups: non-medicated (Control) and 4 groups including treatment with etomidate or midazolam at 1 and 50 µM (n = 3 per group). The cell counting kit-8 assay was performed for determining the cell proliferation in both medium groups at day 0, 3, 6, 9, 12, and 15 in culture. The absorbance values at 450 nm were then measured by enzyme-linked immunosorbent assay reader and statistically compared among groups. RESULTS: There was no significant difference in cell proliferation profiles among the 5 groups at any time point in both control and adipogenic differentiation media. CONCLUSIONS: Etomidate and midazolam did not influence ADSC proliferation under both media when compared to the non-medicated group and there was no dose-dependent effect of etomidate and midazolam on ADSC viability.

Neonatal Propofol and Etomidate Exposure Enhance Inhibitory Synaptic Transmission in Hippocampal Cornus Ammonis 1 Pyramidal Neurons / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Propofol and etomidate are the most important intravenous general anesthetics in the current clinical use and that mediate gamma-aminobutyric acid's (GABAergic) synaptic transmission. However, their long-term effects on GABAergic synaptic transmission induced by neonatal propofol or etomidate exposure remain unclear. We investigated the long-term GABAergic neurotransmission alterations, following neonatal propofol and etomidate administration.</p><p><b>METHODS</b>Sprague-Dawley rat pups at postnatal days 4-6 were underwent 6-h-long propofol-induced or 5-h-long etomidate-induced anesthesia. We performed whole-cell patch-clamp recording from pyramidal cells in the cornus ammonis 1 area of acute hippocampal slices of postnatal 80-90 days. Spontaneous and miniature inhibitory GABAergic currents (spontaneous inhibitory postsynaptic currents [sIPSCs] and miniature inhibitory postsynaptic currents [mIPSCs]) and their kinetic characters were measured. The glutamatergic tonic effect on inhibitory transmission and the effect of bumetanide on neonatal propofol exposure were also examined.</p><p><b>RESULTS</b>Neonatal propofol exposure significantly increased the frequency of mIPSCs (from 1.87 ± 0.35 Hz to 3.43 ± 0.51 Hz, P< 0.05) and did not affect the amplitude of mIPSCs and sIPSCs. Both propofol and etomidate slowed the decay time of mIPSCs kinetics (168.39 ± 27.91 ms and 267.02 ± 100.08 ms vs. 68.18 ± 12.43 ms; P< 0.05). Bumetanide significantly blocked the frequency increase and reversed the kinetic alteration of mIPSCs induced by neonatal propofol exposure (3.01 ± 0.45 Hz and 94.30 ± 32.56 ms).</p><p><b>CONCLUSIONS</b>Neonatal propofol and etomidate exposure has long-term effects on inhibitory GABAergic transmission. Propofol might act at pre- and post-synaptic GABA receptor A (GABAA) receptors within GABAergic synapses and impairs the glutamatergic tonic input to GABAergic synapses; etomidate might act at the postsynaptic site.</p>

Establishment of an anesthesia model induced by etomidate in larval zebrafish / 生理学报

Despite the wide application of general anesthetic drugs in clinic, it is still unclear how these drugs induce the state of general anesthesia. Larval zebrafish has emerged as an ideal model for dissecting the mechanism of neural systems due to the conserved and simple brain structure. In the present study, we established an anesthesia model from behavioral to electrophysiological levels using larval zebrafish for the first time. Bath application of etomidate, as a kind of intravenous anesthetic drugs, suppressed the spontaneous locomotion of zebrafish in a concentration-dependent manner. Consistently, in vivo fictive motor patterns of spinal motoneurons recorded extracellularly were significantly inhibited as well. Furthermore, using in vivo extracellular recording and whole-cell recording, we found that etomidate application suppressed local field potentials (LFP) of the brain and blocked visually evoked responses of optic tectal neurons. The study indicates that larval zebrafish can serve as an ideal vertebrate animal model for studying neural mechanisms underlying general anesthesia.

Underlying Mechanisms of Memory Deficits Induced by Etomidate Anesthesia in Aged Rat Model: Critical Role of Immediate Early Genes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Etomidate (R-1-[1-ethylphenyl] imidazole-5-ethyl ester) is a widely used anesthetic drug that had been reported to contribute to cognitive deficits after general surgery. However, its underlying mechanisms have not been fully elucidated. In this study, we aimed to explore the neurobiological mechanisms of cognitive impairments that caused by etomidate.</p><p><b>METHODS</b>A total of 30 Sprague-Dawley rats were used and divided into two groups randomly to receive a single injection of etomidate or vehicle. Then, the rats' spatial memory ability and neuronal survival were evaluated using the Morris water maze test and Nissl staining, respectively. Furthermore, we analyzed levels of oxidative stress, as well as cyclic adenosine 3',5'-monophosphate response element-binding (CREB) protein phosphorylation and immediate early gene (IEG, including Arc, c-fos, and Egr1) expression levels using Western blot analysis.</p><p><b>RESULTS</b>Compared with vehicle-treated rats, the etomidate-treated rats displayed impaired spatial learning (day 4: 27.26 ± 5.33 s vs. 35.52 ± 3.88 s, t = 2.988, P = 0.0068; day 5: 15.84 ± 4.02 s vs. 30.67 ± 4.23 s, t = 3.013, P = 0.0057; day 6: 9.47 ± 2.35 s vs. 25.66 ± 4.16 s, t = 3.567, P = 0.0036) and memory ability (crossing times: 4.40 ± 1.18 vs. 2.06 ± 0.80, t = 2.896, P = 0.0072; duration: 34.00 ± 4.24 s vs. 18.07 ± 4.79 s, t = 3.023, P = 0.0053; total swimming distance: 40.73 ± 3.45 cm vs. 27.40 ± 6.56 cm, t = 2.798, P = 0.0086) but no neuronal death. Furthermore, etomidate did not cause oxidative stress or deficits in CREB phosphorylation. The levels of multiple IEGs (Arc: vehicle treated rats 100%, etomidate treated rats 86%, t = 2.876, P = 0.0086; c-fos: Vehicle treated rats 100%, etomidate treated rats 72%, t = 2.996, P = 0.0076; Egr1: Vehicle treated rats 100%, etomidate treated rats 58%, t = 3.011, P = 0.0057) were significantly reduced in hippocampi of etomidate-treated rats.</p><p><b>CONCLUSION</b>Our data suggested that etomidate might induce memory impairment in rats via inhibition of IEG expression.</p>

Cardioversion: What to choose Etomidate or propofol.

Context: Electrical cardioversion is a short painful procedure to regain normal sinus rhythm requiring anaesthesia for haemodynamic stability, sedation, analgesia and early recovery. Aims: To compare propofol and etomidate as sedatives during cardioversion. Settings and Design: Single centred, prospective and randomized single blind study comprising 60 patients. Subjects and Methods: Patients more than 18 years, American Society of Anesthesiologists I/II/III grades undergoing elective cardioversion, randomly divided to receive propofol 1 mg/kg intravenous (IV) bolus followed by 0.5 mg/kg (Group P, n = 30) or etomidate (Group E, n = 30) 0.1 mg/kg followed by 0.05 mg/kg. All patients received IV fentanyl (1 μg/kg) before procedure. Heart rate, blood pressure (BP) (systolic BP [SBP], diastolic BP [DBP], mean arterial pressure), respiratory rate, Aldrete recovery score (ARS) and Ramsay sedation score (RSS) were assessed at 1, 2, 5, 10, 15, 20 and 30 min post cardioversion. Incidence of hypotension, respiratory depression and side effects were compared. Statistical analysis used: Student’s unpaired t‑test, Chi‑square test and Mann–Whitney test. P < 0.05 was taken as significant. Results: Group P showed significant fall in SBP, DBP, and mean BP at 2 min after cardioversion. Hypotension (33.3% Group P vs. 16.65% Group E) occurred more with propofol (P < 0.05). Group E showed better ARS at 1, 2, 5, 10, 15 and 20 min. Time required to attain RSS = 2 (659.1 s Group P and 435.7 s Group E) indicated longer recovery with propofol. Left atrial size (35.5-42.5 mm) did not affect success rate of cardioversion (80% Group P vs. 83.3% Group E). Incidence of myoclonus (Group E 26.67% vs. Group P 0%) showed significant difference. Conclusions: Etomidate/fentanyl is superior over propofol/fentanyl during cardioversion for quick recovery and haemodynamic stability.

Effect of etomidate and propofol induction on hemodynamic and endocrine response in patients undergoing coronary artery bypass grafting/mitral valve and aortic valve replacement surgery on cardiopulmonary bypass.

Introduction: The concerns for induction of anaesthesia in patients undergoing cardiac surgery include hemodynamic stability, attenuation of stress response and maintenance of balance between myocardial oxygen demand and supply. Various Intravenous anaesthetic agents like Thiopentone, Etomidate, Propofol, Midazolam, and Ketamine have been used for anesthetizing patients for cardiac surgeries. However, many authors have expressed concerns regarding induction with thiopentone, midazolam and ketamine. Hence, Propofol and Etomidate are preferred for induction in these patients. However, these two drugs have different characteristics. Etomidate is preferred for patients with poor left ventricular (LV) function as it provides stable cardiovascular profile. But there are concerns about reduction in adrenal suppression and serum cortisol levels. Propofol, on the other hand may cause a reduction in systemic vascular resistance and subsequent hypotension. Thus, this study was conducted to compare induction with these two agents in cardiac surgeries. Methods: Baseline categorical and continuous variables were compared using Fisher’s exact test and student’s t test respectively. Hemodynamic variables were compared using student’s t test for independent samples. The primary outcome (serum cortisol and blood sugar) of the study was compared using Wilcoxon Rank Sum test. The P value less than 0.05 was considered significant. Results: Etomidate provides more stable hemodynamic parameters as compared to Propofol. Propofol causes vasodilation and may result in drop of systematic BP. Etomidate can therefore be safely used for induction in patients with good LV function for CABG/MVR/AVR on CPB without serious cortisol suppression lasting more than twenty-four hours.

Effects of conventional vs high-dose rocuronium on the QTc interval during anesthesia induction and intubation in patients undergoing coronary artery surgery: a randomized, double-blind, parallel trial

Myocardial ischemia, as well as the induction agents used in anesthesia, may cause corrected QT interval (QTc) prolongation. The objective of this randomized, double-blind trial was to determine the effects of high- vs conventional-dose bolus rocuronium on QTc duration and the incidence of dysrhythmias following anesthesia induction and intubation. Fifty patients about to undergo coronary artery surgery were randomly allocated to receive conventional-dose (0.6 mg/kg, group C, n=25) or high-dose (1.2 mg/kg, group H, n=25) rocuronium after induction with etomidate and fentanyl. QTc, heart rate, and mean arterial pressure were recorded before induction (T0), after induction (T1), after rocuronium (just before laryngoscopy; T2), 2 min after intubation (T3), and 5 min after intubation (T4). The occurrence of dysrhythmias was recorded. In both groups, QTc was significantly longer at T3 than at baseline [475 vs 429 ms in group C (P=0.001), and 459 vs 434 ms in group H (P=0.005)]. The incidence of dysrhythmias in group C (28%) and in group H (24%) was similar. The QTc after high-dose rocuronium was not significantly longer than after conventional-dose rocuronium in patients about to undergo coronary artery surgery who were induced with etomidate and fentanyl. In both groups, compared with baseline, QTc was most prolonged at 2 min after intubation, suggesting that QTc prolongation may be due to the nociceptive stimulus of intubation.