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1.
Medicine (Baltimore) ; 99(5): e18441, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000357

RESUMO

Various methods of assessing the depth of anesthesia (DoA) and reducing intraoperative awareness during general anesthesia have been extensively studied in anesthesiology. However, most of the DoA monitors do not include brain activity signal modeling. Here, we propose a new algorithm termed the cortical activity index (CAI) based on the brain activity signals. In this study, we enrolled 32 patients who underwent laparoscopic cholecystectomy. Raw electroencephalography (EEG) signals were acquired at a sampling rate of 128 Hz using BIS-VISTA with standard bispectral index (BIS) sensors. All data were stored on a computer for further analysis. The similarities and difference among spectral entropy, the BIS, and CAI were analyzed. Pearson correlation coefficient between the BIS and CAI was 0.825. The result of fitting the semiparametric regression models is the method CAI estimate (-0.00995; P = .0341). It is the estimated difference in the mean of the dependent variable between method BIS and CAI. The CAI algorithm, a simple and intuitive algorithm based on brain activity signal modeling, suggests an intrinsic relationship between the DoA and the EEG waveform. We suggest that the CAI algorithm might be used to quantify the DoA.


Assuntos
Algoritmos , Anestesia , Anestésicos/farmacologia , Córtex Cerebral/efeitos dos fármacos , Eletroencefalografia , Adulto , Colecistectomia Laparoscópica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
2.
J Zoo Wildl Med ; 50(4): 868-873, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31926517

RESUMO

Blue poison dart frogs (Dendrobates tinctorius azureus) are commonly maintained in zoological institutions and are becoming popular in the pet trade industry. Sedation or light anesthesia is required for safe and effective handling of this species. In this study, the sedative effects of subcutaneously administered alfaxalone-midazolam-dexmedetomidine (AMD) (20, 40, 5 mg/kg, respectively) and ketamine-midazolam-dexmedetomidine (KMD) (100, 40, 5 mg/kg, respectively) were compared in a prospective, randomized, blinded, crossover study in juvenile blue poison dart frogs (n = 10). Both protocols were partially reversed 45 min after administration of either protocol with subcutaneously administered flumazenil (0.05 mg/kg) and atipamezole (50 mg/kg). Heart rate, pulmonic respiratory rate, various reflexes, and behavioral parameters were monitored after drug administration. Both protocols resulted in rapid loss of righting reflex [median (range): AMD, 5 min (5-5 min); KMD, 5 min (5-10 min)]. Time to complete recovery was similar with both protocols (mean ± SD: AMD, 97.5 ± 11.4 min; KMD, 96.5 ± 25.4 min). The AMD protocol resulted in pulmonic respiratory depression, whereas no significant difference in heart rate was found between the two protocols. All frogs were observed eating within 24 hr of chemical restraint. Gastric prolapses occurred in four frogs (AMD 3, KMD 1) that were easily reduced with a cotton-tip application. No other adverse reactions were observed. The results of this study provide two different subcutaneous chemical restraint protocols in juvenile blue poison dart frogs.


Assuntos
Dexmedetomidina/farmacologia , Midazolam/farmacologia , Pregnanodionas/farmacologia , Antagonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Antagonistas de Receptores Adrenérgicos alfa 2/farmacologia , Envelhecimento , Analgésicos/administração & dosagem , Analgésicos/farmacologia , Anestésicos/administração & dosagem , Anestésicos/farmacologia , Animais , Antídotos/administração & dosagem , Antídotos/farmacologia , Anuros , Sedação Consciente , Estudos Cross-Over , Dexmedetomidina/administração & dosagem , Quimioterapia Combinada , Flumazenil/administração & dosagem , Flumazenil/farmacologia , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Ketamina/administração & dosagem , Ketamina/farmacologia , Midazolam/administração & dosagem , Pregnanodionas/administração & dosagem
3.
Curr Opin Anaesthesiol ; 33(1): 109-113, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31789903

RESUMO

PURPOSE OF REVIEW: With the growing of the aging population, increased and new methods of anesthesia and surgery allow for surgery and other interventions in older adults.Pharmacokinetics and pharmacodynamics of drugs in older adults differ from those in younger and middle-aged adults. However, the geriatric population is frequently neglected in the context of clinical trials. The present review focuses on the consequences of multimorbidity and pharmacokinetic and pharmacodynamic alterations and their implications on anesthesia. RECENT FINDINGS: Physiologically based pharmacokinetic and pharmacodynamic modeling may serve as an option to better understand the influence of age on drugs used for anesthesia. However, difficulties to adequately characterize geriatric patients are described. SUMMARY: Further research of drug effects in the aging population may include physiologically based pharmacokinetic and pharmacodynamic complex models and randomized controlled trials with thoroughly conducted geriatric assessments.


Assuntos
Anestesia , Anestesiologia , Anestésicos , Idoso , Anestésicos/farmacocinética , Anestésicos/farmacologia , Avaliação Geriátrica , Humanos , Pessoa de Meia-Idade
4.
BMJ ; 367: l6459, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31818811

RESUMO

General anesthesia has been unequivocally linked to abnormal development of the central nervous system, leading to neurocognitive impairments in laboratory models. In vitro and in vivo studies have consistently shown that exposure to GABA agonists (eg, volatile anesthetics, midazolam, and propofol) or NMDA antagonists (eg, ketamine, isoflurane, and nitrous oxide) produces dose dependent and developmental age dependent effects on various neuronal transmission systems. Exposure to these drugs increases neuronal cell death in juvenile animals including rats, mice, and non-human primates. The possibility of anesthetic induced neurotoxicity occurring in children has led to concerns about the safety of pediatric anesthesia. A spectrum of behavioral changes has been documented after general anesthetic exposure in young children, including emergence delirium, which may be evidence of toxicity. Most clinical studies are retrospective; specifics about medications or monitoring are unavailable and many of the outcomes may not be sensitive to detect small neurocognitive deficits. Some of these retrospective studies have shown an association between anesthesia exposure at a young age and neurocognitive deficits, but others have not. Practitioners and families should be reassured that although general anesthetics have the potential to induce neurotoxicity, very little clinical evidence exists to support this.


Assuntos
Anestesia Geral/efeitos adversos , Anestésicos/farmacologia , Sistema Nervoso Central , Transtornos do Neurodesenvolvimento/induzido quimicamente , Síndromes Neurotóxicas/etiologia , Animais , Sistema Nervoso Central/efeitos dos fármacos , Sistema Nervoso Central/crescimento & desenvolvimento , Criança , Ensaios Clínicos como Assunto , Modelos Animais de Doenças , Humanos , Lactente , Fatores de Risco
5.
Spine (Phila Pa 1976) ; 44(21): 1492-1498, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31609917

RESUMO

STUDY DESIGN: A prospective, within-subject study was conducted. OBJECTIVE: We aimed to compare the influence of anesthetic fade under maximum stimulation conditions between constant-current and constant-voltage stimulation techniques. SUMMARY OF BACKGROUND DATA: The monitoring of muscle-evoked potentials after electrical stimulation to the brain [Br(E)-MSEP)] is useful for assessing the integrity of spinal cord motor tracts during major spine surgery. Nonetheless, Br(E)-MSEP responses are known to deteriorate over the duration of surgeries performed under general anesthesia. This phenomenon is known as anesthetic fade. METHODS: We recruited 117 patients undergoing various spinal surgeries from the cervical to the lumbar level. We excluded 29 cases with insufficient data. The decrease rate of the Br(E)-MSEP amplitude for each muscle was examined. Br(E)-MSEP monitoring with constant-current and constant-voltage stimulations at the C3 and C4 electrode positions was applied. Compound muscle action potentials (CMAPs) were bilaterally recorded from the abductor pollicis brevis, deltoid, abductor hallucis, tibialis anterior, gastrocnemius, and quadriceps muscles. We defined the decrease rate as follows: (initial CMAPs-final CMAPs)/initial CMAPs × 100. Differences in the decrease rate were evaluated between stimulators, limbs (upper vs. lower), and operative time group (lowest quartile vs. highest quartile). RESULTS: The overall decrease rate (across all muscles) increased as the operative time increased, and the rate was higher in the lower limbs than in the upper limbs. In addition, the overall decrease rate was lower with constant-voltage stimulation than with constant-current stimulation. Furthermore, the decrease rate for constant-current stimulation was significantly higher than that for constant-voltage stimulation, regardless of the operative time. CONCLUSION: The CMAP waveform with constant-voltage stimulation is less susceptible to anesthetic fade than that with constant-current stimulation, even during long surgeries. LEVEL OF EVIDENCE: 3.


Assuntos
Anestésicos/farmacologia , Encéfalo/efeitos dos fármacos , Potencial Evocado Motor/fisiologia , Músculo Esquelético/fisiologia , Procedimentos Neurocirúrgicos/métodos , Coluna Vertebral/cirurgia , Adulto , Anestesia Geral , Estimulação Elétrica , Eletrodos , Potenciais Evocados , Feminino , Humanos , Extremidade Inferior , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
6.
Lancet ; 394(10212): 1907-1914, 2019 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645286

RESUMO

BACKGROUND: An association between increasing anaesthetic depth and decreased postoperative survival has been shown in observational studies; however, evidence from randomised controlled trials is lacking. Our aim was to compare all-cause 1-year mortality in older patients having major surgery and randomly assigned to light or deep general anaesthesia. METHODS: In an international trial, we recruited patients from 73 centres in seven countries who were aged 60 years and older, with significant comorbidity, having surgery with expected duration of more than 2 h, and an anticipated hospital stay of at least 2 days. We randomly assigned patients who had increased risk of complications after major surgery to receive light general anaesthesia (bispectral index [BIS] target 50) or deep general anaesthesia (BIS target 35). Anaesthetists also nominated an appropriate range for mean arterial pressure for each patient during surgery. Patients were randomly assigned in permuted blocks by region immediately before surgery, with the patient and assessors masked to group allocation. The primary outcome was 1-year all-cause mortality. The trial is registered with the Australian New Zealand Clinical Trials Registry, ACTRN12612000632897, and is closed to accrual. FINDINGS: Patients were enrolled between Dec 19, 2012, and Dec 12, 2017. Of the 18 026 patients screened as eligible, 6644 were enrolled, randomly assigned to treatment or control, and formed the intention-to-treat population (3316 in the BIS 50 group and 3328 in the BIS 35 group). The median BIS was 47·2 (IQR 43·7 to 50·5) in the BIS 50 group and 38·8 (36·3 to 42·4) in the BIS 35 group. Mean arterial pressure was 3·5 mm Hg (4%) higher (median 84·5 [IQR 78·0 to 91·3] and 81·0 [75·4 to 87·6], respectively) and volatile anaesthetic use was 0·26 minimum alveolar concentration (30%) lower (0·62 [0·52 to 0·73] and 0·88 [0·74 to 1·04], respectively) in the BIS 50 than the BIS 35 group. 1-year mortality was 6·5% (212 patients) in the BIS 50 group and 7·2% (238 patients) in the BIS 35 group (hazard ratio 0·88, 95% CI 0·73 to 1·07, absolute risk reduction 0·8%, 95% CI -0·5 to 2·0). Grade 3 adverse events occurred in 954 (29%) patients in the BIS 50 group and 909 (27%) patients in the BIS 35 group; and grade 4 adverse events in 265 (8%) and 259 (8%) patients, respectively. The most commonly reported adverse events were infections, vascular disorders, cardiac disorders, and neoplasms. INTERPRETATION: Among patients at increased risk of complications after major surgery, light general anaesthesia was not associated with lower 1-year mortality than deep general anaesthesia. Our trial defines a broad range of anaesthetic depth over which anaesthesia may be safely delivered when titrating volatile anaesthetic concentrations using a processed electroencephalographic monitor. FUNDING: Health Research Council of New Zealand; National Health and Medical Research Council, Australia; Research Grant Council of Hong Kong; National Institute for Health and Research, UK; and National Institutes of Health, USA.


Assuntos
Anestesia Geral/efeitos adversos , Anestesia Geral/mortalidade , Anestésicos/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Idoso , Anestesia Geral/métodos , Anestésicos/farmacologia , Pressão Arterial , Monitores de Consciência , Feminino , Humanos , Masculino , Período Pós-Operatório
7.
Artigo em Alemão | MEDLINE | ID: mdl-31639858

RESUMO

The rapid sequence induction (RSI) is a not evidence-based technique designed to minimize the chance of pulmonary aspiration in high-risk patients requiring general anesthesia. Primary aim of this anesthetic technique is, therefore, a fast airway protection with an endotracheal tube to reduce the chance of passive or active regurgitation. This article discusses the anesthetic management of patients with an increased risk of aspiration, and, particularly, refers to the medications required for RSI.


Assuntos
Anestesia Geral , Anestésicos , Anestésicos/administração & dosagem , Anestésicos/farmacologia , Humanos , Intubação Intratraqueal
8.
South Med J ; 112(9): 491-496, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31485589

RESUMO

OBJECTIVES: The purpose of this study was to identify the incidence of anesthetic errors per discharges in the United States within these errors, the incidence of death. A secondary aim was to identify any association between the mortality and patient comorbidities. METHODS: A retrospective analysis of the hospitals in the United States using the Nationwide Inpatient Sample (NIS) database during 2007-2014 was performed. The study population consisted of patients who were recorded as inpatient discharges who experienced complications as a result of incorrect anesthetic administration resulting from either an overdose or inappropriate medication administration in the United States. RESULTS: Between 2007 and 2014, a total of 17,116 anesthetic errors were reported. There was a substantial decrease in the total number of these errors over time, from 2483 in 2007 to 1391 in 2014 (44% decrease). There were 131 reported deaths in this cohort (0.77% mortality rate), with 61 mortalities in teaching hospitals (0.86% mortality rate) and 57 in nonteaching hospitals (0.73% mortality rate). During the study period, deaths decreased from 21 in 2007 (0.85% mortality rate) to 11 in 2014 (0.79% mortality rate), corresponding with a 7.1% decrease in the mortality rate. Comorbidities associated with a significant increase in mortality from anesthetic substances included fluid and electrolyte disorders (odds ratio 8.82, 95% confidence interval 5.24-14.83, P < 0.001) and coagulopathies (odds ratio 5.26, 95% confidence interval 2.53-10.93, P < 0.001). CONCLUSIONS: Our study showed that although the incidence of anesthetic errors is small, they do still exist in our hospitals. Certain comorbidities appear to predispose patients to increased risk. The subsets of patients who appear to be at the greatest risk include those with preexisting electrolyte and fluid disorders and coagulopathies.


Assuntos
Anestesia/efeitos adversos , Anestésicos/farmacologia , Erros Médicos/estatística & dados numéricos , Erros de Medicação/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Estados Unidos/epidemiologia
9.
Biomed Pharmacother ; 118: 109308, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31401396

RESUMO

Remote preconditioning of trauma (RPCT) by surgical incision is an effective cardioprotective strategy via the transient receptor potential vanilloid 1 (TRPV1) channel as a form of remote ischemic preconditioning (RIPC). However, cardioprotection by RIPC has been shown to be completely blocked by propofol. We thus hypothesized that propofol may interfere with RPCT induced cardioprotection, and that RPCT induces cardioprotection via the cardiac TRPV1 channel. Male Sprague-Dawley rats were subjected to 30 min of myocardial ischemia followed by 2 h of reperfusion. RPCT was achieved by a transverse abdominal incision. Additionally, propofol or the TRPV1 receptor inhibitor capsazepine (CPZ) was given before RPCT. Infarct size was assessed by triphenyltetrazolium staining. Heart TRPV1 expression was detected by Western blot and immunofluorescence. RPCT significantly reduced infarct size compared to control treatment (45.6 ±â€¯4% versus 65.4 ±â€¯2%, P < 0.01). This protective effect of RPCT was completely abolished by propofol and CPZ. TRPV1 channels are present in the heart. Therefore, cardioprotection by RPCT is also abolished by propofol, and cardiac TRPV1 mediates this cardioprotection.


Assuntos
Cardiotônicos/farmacologia , Precondicionamento Isquêmico , Propofol/farmacologia , Canais de Cátion TRPV/metabolismo , Ferimentos e Lesões/patologia , Anestésicos/farmacologia , Animais , Hemodinâmica/efeitos dos fármacos , Masculino , Ratos Sprague-Dawley
10.
J Craniofac Surg ; 30(8): 2469-2472, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31469734

RESUMO

INTRODUCTION: Flap surgery is one of the most commonly used techniques of reconstructive surgery for effective repair of damaged tissue. Optimal anesthetic technique and anesthetic agent plays an important role in flap perfusion. This study aimed to evaluate the effects of dexmedetomidine infusion on the microcirculation in the cremaster muscle flap by direct in vivo monitoring. MATERIALS AND METHODS: We randomly divided 9 Wistar albino rats into 3 groups. The rats in the control group underwent the surgical procedure (isolation of the cremaster muscle) alone; the rats in the experimental groups 1 and 2 received an infusion of dexmedetomidine (10 and 30 min) after the surgical procedure. RESULTS: The means of vessel diameters, number of functional capillaries, and movements of leukocytes in all groups were evaluated using intravital microscopic examination. The diameters of the arterioles and venules of the cremaster muscle significantly increased in the dexmedetomidine groups. The number of functional capillaries was higher in the dexmedetomidine groups than in the control group. No difference was observed in the movements of leukocytes between the control and experimental groups. Dexmedetomidine significantly increased the diameters of the arterioles and venules of the cremaster flap and the number of functional capillaries. CONCLUSION: On the basis of the effects of dexmedetomidine on microcirculation, we suggest that dexmedetomidine continue to be used as an anesthetic agent, and may be considered also for reconstructive procedures, particularly flap surgery.


Assuntos
Anestésicos/farmacologia , Dexmedetomidina/farmacologia , Músculos Abdominais , Animais , Capilares , Leucócitos , Microcirculação , Ratos , Ratos Wistar , Retalhos Cirúrgicos
11.
Br J Anaesth ; 123(4): 479-487, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31326088

RESUMO

BACKGROUND: Sedation indicators based on a single quantitative EEG (QEEG) feature have been criticised for their limited performance. We hypothesised that integration of multiple QEEG features into a single sedation-level estimator using a machine learning algorithm could reliably predict levels of sedation, independent of the sedative drug used. METHODS: In total, 102 subjects receiving propofol (N=36; 16 male/20 female), sevoflurane (N=36; 16 male/20 female), or dexmedetomidine (N=30; 15 male/15 female) were included in this study of healthy volunteers. Sedation level was assessed using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score. We used 44 QEEG features estimated from the EEG data in a logistic regression algorithm, and an elastic-net regularisation method was used for feature selection. The area under the receiver operator characteristic curve (AUC) was used to assess the performance of the logistic regression model. RESULTS: The performances obtained when the system was trained and tested as drug-dependent mode to distinguish between awake and sedated states (mean AUC [standard deviation]) were propofol=0.97 (0.03), sevoflurane=0.74 (0.25), and dexmedetomidine=0.77 (0.10). The drug-independent system resulted in mean AUC=0.83 (0.17) to discriminate between the awake and sedated states. CONCLUSIONS: The incorporation of large numbers of QEEG features and machine learning algorithms is feasible for next-generation monitors of sedation level. Different QEEG features were selected for propofol, sevoflurane, and dexmedetomidine groups, but the sedation-level estimator maintained a high performance for predicting MOAA/S independent of the drug used. CLINICAL TRIAL REGISTRATION: NCT02043938; NCT03143972.


Assuntos
Anestésicos/farmacologia , Monitores de Consciência , Eletroencefalografia/estatística & dados numéricos , Lobo Frontal/efeitos dos fármacos , Aprendizado de Máquina , Vigília/efeitos dos fármacos , Humanos , Valores de Referência , Reprodutibilidade dos Testes
12.
J Avian Med Surg ; 33(2): 115-122, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251498

RESUMO

This study was conducted to compare the effects of 3 different sedative agents on electroretinography (ERG) in domestic pigeons (Columba livia). Six pigeons were sedated with alfaxalone, xylazine, and medetomidine at separate times with a 1-week washout period between sedative administration. After sedation with each agent, pigeons underwent the modified ERG protocol adapted from the standardized protocol for dogs. The scotopic mixed rod and cone response was recorded after 20 minutes of dark adaptation, and the photopic cone response and photopic flicker response were recorded after 10 minutes of light adaptation. Either a 1-way analysis of variance or a Kruskall-Wallis test was used to compare the a-wave and b-wave implicit time and amplitude. No significant differences were observed in the scotopic mixed rod and cone response among all 3 sedatives used. Compared with alfaxalone, medetomidine significantly prolonged the a-wave implicit time, depressed the b-wave amplitude of photopic cone response, and prolonged the peak implicit time of the photopic flicker response (P < .05). These results show that medetomidine has a depressant effect on photopic ERG in pigeons at a dosage that produces light sedation.


Assuntos
Columbidae , Eletrorretinografia/veterinária , Medetomidina/farmacologia , Pregnanodionas/farmacologia , Xilazina/farmacologia , Anestésicos/farmacologia , Animais , Estudos Cross-Over , Hipnóticos e Sedativos/farmacologia
13.
Zebrafish ; 16(5): 451-459, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31188070

RESUMO

Since the use of the zebrafish Danio rerio genetic model organism within the scientific research community continues to grow rapidly, continued procedural refinement to support high-quality, reproducible research and improve animal welfare remains an important focus. As such, anesthesia remains one of the most frequent procedures conducted. Here, we compared the effectiveness of clove oil (active ingredient eugenol) and AQUI-S (active ingredient iso-eugenol) with the currently most commonly used tricaine/MS-222 (ethyl 3-aminobenzoate methanesulfonate) and benzocaine anesthesia. We focused on embryos (1 day postfertilization), larvae (5 days postfertilization), and adults (9-11 months) and for the first time used exposure times that are the most relevant in research settings by using zebrafish as a genetic model system. For each age, tricaine and benzocaine achieved the most reproducible, robust anesthesia with the quickest induction and recovery. For some experimental procedures, specific clove oil concentrations in embryos and larvae may represent suitable alternatives. Although different aquatic species at specific ages respond differentially to these agents, the systematic study of comparable effective dosages for procedures most commonly employed represent an important step toward refinement.


Assuntos
Anestesia/veterinária , Anestésicos/farmacologia , Óleo de Cravo/farmacologia , Embrião não Mamífero/efeitos dos fármacos , Eugenol/farmacologia , Peixe-Zebra/embriologia , Anestésicos/administração & dosagem , Animais , Larva/efeitos dos fármacos
14.
Front Neural Circuits ; 13: 38, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191258

RESUMO

Monitoring the hypnotic component of anesthesia during surgeries is critical to prevent intraoperative awareness and reduce adverse side effects. For this purpose, electroencephalographic (EEG) methods complementing measures of autonomic functions and behavioral responses are in use in clinical practice. However, in human neonates and infants existing methods may be unreliable and the correlation between brain activity and anesthetic depth is still poorly understood. Here, we characterized the effects of different anesthetics on brain activity in neonatal mice and developed machine learning approaches to identify electrophysiological features predicting inspired or end-tidal anesthetic concentration as a proxy for anesthetic depth. We show that similar features from EEG recordings can be applied to predict anesthetic concentration in neonatal mice and humans. These results might support a novel strategy to monitor anesthetic depth in human newborns.


Assuntos
Algoritmos , Anestesia , Anestésicos/farmacologia , Encéfalo/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Encéfalo/fisiologia , Eletroencefalografia , Feminino , Humanos , Lactente , Recém-Nascido , Aprendizado de Máquina , Masculino , Camundongos , Camundongos Endogâmicos C57BL
15.
Vet Anaesth Analg ; 46(4): 458-465, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31196750

RESUMO

OBJECTIVE: To determine time to first passage of feces, total fecal piles and incidence of colic in the first 24 hours postprocedure in horses undergoing standing sedation with detomidine, or general anesthesia with or without detomidine. STUDY DESIGN: Retrospective cohort study. ANIMALS: A total of 246 horses. METHODS: Records of all horses that underwent standing sedation or general anesthesia between December 2012 and March 2016 were reviewed. Horses aged <6 months, admitted for colic or cesarean section, with inadequate data, and those not administered xylazine and/or detomidine were excluded. Records included patient signalment, fasting duration, procedure performed, drugs administered, time to first feces, number of fecal piles during 24 hours postprocedure and mention of colic. Chi-square, Fisher's exact and Tukey's post hoc comparison tests were used. Parametric data were reported as mean ± standard deviation with significance defined as p <0.05. RESULTS: In total, 116 and 57 horses underwent general anesthesia without detomidine (group GA) and with detomidine (group GA-D), respectively, and remaining 73 horses underwent standing sedation with detomidine (group S-D). Detomidine dose was significantly higher in group S-D than in group GA-D. Time to first feces was longer (7.1 ± 4.2 hours), and group S-D horses passed one fewer fecal pile (6.3 ± 2.4) than group GA horses. There was no interaction between detomidine treatment and preprocedure food withholding and the time to first feces or the number of fecal piles in the first 24 hours postprocedure. Overall, seven horses (2.8%) showed signs of colic (five, one and one in GA, GA-D and S-D, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Detomidine administration, as part of an anesthetic protocol or for standing sedation procedures, should not be expected to contribute to postprocedural colic.


Assuntos
Cólica/veterinária , Sedação Consciente/veterinária , Fezes , Motilidade Gastrointestinal/fisiologia , Doenças dos Cavalos/cirurgia , Imidazóis/farmacologia , Anestesia/veterinária , Anestésicos/administração & dosagem , Anestésicos/efeitos adversos , Anestésicos/farmacologia , Animais , Cólica/etiologia , Sedação Consciente/efeitos adversos , Feminino , Cavalos , Imidazóis/administração & dosagem , Masculino , Complicações Pós-Operatórias/veterinária , Estudos Retrospectivos
16.
Vet Anaesth Analg ; 46(4): 435-442, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31202619

RESUMO

OBJECTIVE: To compare the effect of chemical and mechanical stimulation on arytenoid cartilage motion during anaesthetic induction with alfaxalone, thiopentone or propofol. STUDY DESIGN: Masked, randomized, crossover study. ANIMALS: A group of eight adult Beagle dogs. METHODS: Anaesthesia was induced with thiopentone (7.5 mg kg-1), propofol (3 mg kg-1) or alfaxalone (1.5 mg kg-1) intravenously (IV), which were concurrently paired with either chemical (doxapram at 2.5 mg kg-1 IV) or mechanical (gentle pressure to the corniculate process of the right arytenoid cartilage using a cotton bud) stimulation for enhanced assessment of laryngeal motion, in random order, with a 1 week wash-out period between treatments. If deemed inadequately anaesthetized, supplemental boli of thiopentone (1.8 mg kg-1), propofol (0.75 mg kg-1) or alfaxalone (0.4 mg kg-1) were administered. Assessment of number of arytenoid motions and vital breaths, among others, was initiated immediately after induction. Chemical (doxapram) and mechanical stimulation were begun 2 minutes after anaesthetic induction. Data were collected at 2, 3 and 5 minutes after anaesthetic induction and the Friedman rank-sum or repeated-measures analysis of variance tests were used when applicable for statistical analysis. RESULTS: The duration of examination time was shorter among treatments combined with chemical stimulation (p=0.001). Examination time during induction was longer for alfaxalone-chemical (8.9 minutes) and -mechanical (10.9 minutes) compared to both induction with thiopentone-chemical (3.8 minutes) and propofol-chemical (4.0 minutes). The median number of arytenoid motions for both thiopentone (67) and propofol (59) induction combined with chemical stimulation was significantly higher in comparison to that of alfaxalone (1), thiopentone (2) and propofol (2), when combined with mechanical stimulation at 3 minutes after induction. CONCLUSION AND CLINICAL RELEVANCE: Among the regimens for assessing laryngeal motion assessed in the present study, combinations of thiopentone or propofol with doxapram are the most effective means of stimulating arytenoid motion and could improve the accuracy of diagnosis of laryngeal paralysis in dogs.


Assuntos
Doenças do Cão/diagnóstico , Cães , Pregnanodionas/farmacologia , Propofol/farmacologia , Tiopental/farmacologia , Paralisia das Pregas Vocais/veterinária , Anestesia/veterinária , Anestésicos/administração & dosagem , Anestésicos/farmacologia , Anestésicos Intravenosos/farmacologia , Animais , Estudos Cross-Over , Laringe/efeitos dos fármacos , Laringe/patologia , Pregnanodionas/administração & dosagem , Propofol/administração & dosagem , Distribuição Aleatória , Tiopental/administração & dosagem , Paralisia das Pregas Vocais/diagnóstico
17.
Vet Anaesth Analg ; 46(4): 483-487, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31178411

RESUMO

OBJECTIVE: To describe clinically relevant, physiological measurements collected during a 3 hour duration of alfaxalone total intravenous anaesthesia. STUDY DESIGN: Case series. ANIMALS: A total of 112 client-owned middle-aged or older dogs. METHODS: Dogs were premedicated with intramuscular acepromazine (0.03 mg kg-1). Anaesthesia was induced and subsequently maintained for up to 3 hours with alfaxalone administered intravenously. Dogs breathed 100% oxygen via an endotracheal tube. Heart rate, respiratory rate and blood pressure were evaluated 30 minutes after administration of acepromazine and used as baseline values for comparisons of intra-anaesthetic data. Blood glucose was measured 1 week prior to anaesthesia and every hour during alfaxalone anaesthesia. Quality and duration of recovery were recorded. Mean data for physiological variables were compared over three time points-before induction of anaesthesia, for the first hour of anaesthesia and from 60 minutes to discontinuation of anaesthesia. RESULTS: Mean induction dose of alfaxalone was 1.4 mg kg-1 [95% confidence interval (CI) 1.3-1.5). Post induction apnoea for >60 seconds occurred in 13 (11.6%) dogs. Mean alfaxalone infusion rate during the first 60 minutes of anaesthesia was 0.099 mg kg-1 minute-1; mean infusion rate was 0.092 mg kg-1 minute-1 from 60 minutes until discontinuation of anaesthesia. Heart rate was well maintained; hypotension (mean arterial blood pressure < 60 mmHg) was encountered in 23 (21%) dogs. Blood glucose levels did not alter during anaesthesia. Median time between discontinuation of alfaxalone infusion and extubation was 17 (7-35 minutes), time to assuming sternal recumbency was 75 (58-110 minutes), and time to standing was 109 (88-140 minutes). CONCLUSIONS AND CLINICAL RELEVANCE: Alfaxalone infusion provided effective anaesthesia in this population. In a minority of cases, respiratory and haemodynamic support of the patient was required.


Assuntos
Anestesia Intravenosa/veterinária , Anestésicos/farmacologia , Doenças do Cão/diagnóstico por imagem , Osteoartrite/veterinária , Pregnanodionas/farmacologia , Radiografia/veterinária , Anestésicos/administração & dosagem , Anestésicos/efeitos adversos , Animais , Apneia/induzido quimicamente , Apneia/veterinária , Glicemia , Pressão Sanguínea/efeitos dos fármacos , Dióxido de Carbono/sangue , Estudos de Casos e Controles , Cães , Feminino , Frequência Cardíaca/efeitos dos fármacos , Masculino , Osteoartrite/diagnóstico por imagem , Oxigênio/sangue , Pregnanodionas/administração & dosagem , Pregnanodionas/efeitos adversos , Respiração/efeitos dos fármacos
18.
Vet Anaesth Analg ; 46(4): 421-428, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31178412

RESUMO

OBJECTIVE: To investigate alfaxalone total intravenous anaesthesia (TIVA) following premedication with methadone combined with acepromazine (ACP) or dexmedetomidine in bitches undergoing ovariohysterectomy. STUDY DESIGN: Prospective, blinded, randomized, experimental study. ANIMALS: A group of 12 female Beagles. METHODS: Dogs were premedicated intravenously with methadone (0.2 mg kg-1) combined with ACP (20 µg kg-1, group AM) or dexmedetomidine (5 µg kg-1, group DM). Anaesthesia was induced with alfaxalone (2 mg kg-1). Anaesthetic maintenance was obtained with an alfaxalone variable rate infusion (VRI) started at 0.15 mg kg-1 minute-1 and adjusted every 5 minutes based on clinical assessment. Mechanical ventilation was initiated when necessary to maintain normocapnia. Anaesthetic monitoring included electrocardiogram, heart rate (HR), invasive diastolic (DAP), systolic (SAP) and mean arterial blood pressure, arterial haemoglobin oxygen saturation, respiratory variables and oesophageal temperature. Data were recorded every 5 minutes. A mixed model statistical approach was used to compare cardiovascular variables within and between groups (α = 0.05). A Wilcoxon rank-sum test was used to compare body temperature, VRI alfaxalone rate, administered rescue analgesia, sedation, induction, intubation, recovery scores and recovery times between treatments. RESULTS: Overall HR, SAP and DAP differed between groups (p = 0.001, 0.016, 0.019, respectively). The mean VRI dose rate of alfaxalone differed between groups DM [0.13 (0.11-0.14) mg kg-1 minute-1] and AM [0.18 (0.13-0.19) mg kg-1 minute-1; p = 0.030]. Rescue analgesia was administered more in group AM (p = 0.019). No significant difference in recovery times and scores was observed between protocols. CONCLUSIONS AND CLINICAL RELEVANCE: Alfaxalone TIVA following dexmedetomidine/methadone premedication produced a more stable plane of anaesthesia to perform ovariohysterectomy than ACP/methadone. A dose reduction of alfaxalone of 27.7% was obtained in group DM compared with group AM. Recovery quality and recovery times were comparable between both groups.


Assuntos
Acepromazina/farmacologia , Dexmedetomidina/farmacologia , Cães , Pregnanodionas/farmacologia , Pré-Medicação , Acepromazina/administração & dosagem , Anestésicos/administração & dosagem , Anestésicos/farmacologia , Animais , Dexmedetomidina/administração & dosagem , Antagonistas de Dopamina/administração & dosagem , Antagonistas de Dopamina/farmacologia , Feminino , Hipnóticos e Sedativos/administração & dosagem , Hipnóticos e Sedativos/farmacologia , Histerectomia/veterinária , Metadona , Ovariectomia/veterinária , Pregnanodionas/administração & dosagem , Distribuição Aleatória
19.
J Vet Med Sci ; 81(6): 937-945, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31080189

RESUMO

The anesthetic effects of alfaxalone combined with medetomidine and butorphanol were investigated for ICR, BALB/c, and C57BL/6 mice. Mice were administered a combination of 0.5 or 0.75 mg/kg medetomidine and 5 mg/kg butorphanol with 30 or 40 mg/kg alfaxalone (0.5MBA30, 0.75MBA30 and 0.75MBA40, respectively). The drug combinations were administered subcutaneously and were compared with a widely used combination of 0.3 mg/kg medetomidine, 4 mg/kg midazolam, and 5 mg/kg butorphanol (MMB). All three MBA combinations achieved surgical anesthesia, although the recovery time was longer with 0.75MBA30 and 0.75MBA40 compared with 0.5MBA30. Furthermore, several mice exhibited a considerable jumping reaction immediately after injection with 0.75MBA30 and 0.75MBA40. Therefore, 0.5MBA30 may be suitable for inducing surgical anesthesia in the mouse strains tested. The anesthetic scores for 0.5MBA30 were improved compared with those of MMB in all three mouse strains; however, the body temperature drop in C57BL/6 mice was greater with 0.5MBA30. Our results show that the alfaxalone combination, 0.5MBA30, should allow surgical operations that are more stable in more strains of mice than MMB, although the combination may cause hypothermia, especially in C57BL/6 mice.


Assuntos
Anestesia/veterinária , Anestésicos/farmacologia , Butorfanol/farmacologia , Medetomidina/farmacologia , Pregnanodionas/farmacologia , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/farmacologia , Anestésicos/administração & dosagem , Anestésicos Combinados , Animais , Temperatura Corporal/efeitos dos fármacos , Butorfanol/administração & dosagem , Injeções Subcutâneas/veterinária , Medetomidina/administração & dosagem , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Pregnanodionas/administração & dosagem , Organismos Livres de Patógenos Específicos
20.
Can J Physiol Pharmacol ; 97(9): 850-856, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31116954

RESUMO

It has been assumed that the cardioprotective effects of propofol are due to its non-anesthetic pleiotropic cardiac and vasodilator effects, in which gasotransmitters (NO, H2S, and CO) as well as calcium influx could be involved. The study on isolated rat heart was performed using 4 experimental groups (n = 7 in each): (1) bolus injection of propofol (100 mg/kg body mass, i.p.); (2) L-NAME (NO synthase inhibitor, 60 mg/kg body mass, i.p.) + propofol; (3) DL-PAG (H2S synthase inhibitor, 50 mg/kg body mass, i.p.) + propofol; (4) ZnPPIX (CO synthase inhibitor, 50 µmol/kg body mass, i.p.) + propofol. Before and after the verapamil (3 µmol/L) administration, cardiodynamic parameters were recorded (dp/dtmax, dp/dtmin, systolic left ventricular pressure, diastolic left ventricular pressure, heart rate, coronary flow), as well as coronary and cardiac oxidative stress parameters. The results showed significant increases of diastolic left ventricular pressure following NO and CO inhibition, but also increases of coronary flow following H2S and CO inhibition. Following verapamil administration, significant decreases of dp/dtmax were noted after NO and CO inhibition, then increase of diastolic left ventricular pressure following CO inhibition, and increase of coronary flow following NO, H2S, or CO inhibition. Oxidative stress markers were increased but catalase activity was significantly decreased in cardiac tissue. Gasotransmitters and calcium influx are involved in pleiotropic cardiovascular effects of propofol in male Wistar rats.


Assuntos
Anestésicos/farmacologia , Cálcio/metabolismo , Gasotransmissores/biossíntese , Coração/efeitos dos fármacos , Miocárdio/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Propofol/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Cardiotônicos/farmacologia , Coração/fisiologia , Masculino , Ratos , Ratos Wistar
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