The potent inhalational anesthetic agents are used on a daily basis to provide intraoperative anesthesia. Given their beneficial effects on airway tone and reactivity, they also have a role in the treatment of status asthmaticus that is refractory to standard therapy. Although generally not of clinical significance, these agents can ...

Objective-To characterize the cardiopulmonary effects of dobutamine and norepinephrine infusion in isoflurane-anesthetized healthy alpacas. Animals-8 adult alpacas. Procedures-Initial baseline cardiovascular, respiratory, and metabolic variables were obtained 30 minutes after induction of isoflurane anesthesia in 8 alpacas (3 females and 5 sexually intact males). Four treatments (dobutamine at 4 and 8 ...

BACKGROUND: Hemodynamic responses to vasopressors used during spinal anesthesia for elective Cesarean delivery, have not been well described. This study compared the effects of bolus phenylephrine and ephedrine on maternal cardiac output (CO). The hypothesis was that phenylephrine, but not ephedrine, decreases CO when administered in response to hypotension during ...

OBJECTIVE: To characterize the cardiopulmonary effects of dobutamine and norepinephrine infusion in isoflurane-anesthetized healthy alpacas. ANIMALS: 8 adult alpacas. PROCEDURES: Initial baseline cardiovascular, respiratory, and metabolic variables were obtained 30 minutes after induction of isoflurane anesthesia in 8 alpacas (3 females and 5 sexually intact males). Four treatments (dobutamine at ...

Volatile agent-induced hypotension may contribute to anaesthetic-related morbidity and mortality in horses. Dobutamine is commonly used to support arterial blood pressure (ABP) but little is known about its cardiovascular effects under clinical conditions. The aim of this clinical study was to elucidate the relationship between cardiovascular function and dobutamine infusion ...

BACKGROUND: Hypotension after spinal anesthesia for cesarean delivery is common. Previous studies have demonstrated that a crystalloid fluid "coload" (rapid administration of a fluid bolus starting at the time of intrathecal injection) is superior to the conventional crystalloid preload (fluid administered before the intrathecal injection) for preventing hypotension. Colloid preload ...

OBJECTIVE: To evaluate the accuracy of a commercial ultrasonographic cardiac output (CO) monitoring system (UCOMS) in anesthetized Beagles as assessed by comparison with thermodilution CO (TDCO). ANIMALS: 8 healthy anesthetized Beagles. PROCEDURES: Simultaneous UCOMS and TDCO measurements of CO were obtained during 4 hemodynamic states: baseline anesthesia (0.5% to 1.5% ...

Activation of the peripheral nerve system by endotracheal intubation is accompanied by an increase in bispectral index (BIS). Esmolol produces a dose-dependent attenuation of the adrenergic response to endotracheal intubation. Desflurane increases sympathetic nerve activity and plasma norepinephrine relative to sevoflurane. The authors hypothesized that esmolol might blunt the BIS ...

After intravenous induction, six beagles were connected to a Komesaroff machine provided with a single in-circuit vaporiser and ventilated mechanically at either nine or 14 breaths/minute while anaesthetised with either isoflurane or sevoflurane. The vaporiser was initially set at position 4/4 (fully open) and the anaesthetic concentrations were measured after ...

Objective-To evaluate cardiopulmonary effects of anesthetic induction with diazepam and ketamine or xylazine and ketamine, with subsequent maintenance of anesthesia with isoflurane, in foals undergoing abdominal surgery. Animals-17 pony foals. Procedures-Foals underwent laparotomy at 7 to 15 days of age and laparoscopy 7 to 10 days later. Foals were randomly ...

BACKGROUND: Spinal anesthesia for cesarean delivery may cause severe maternal hypotension, and a decrease in cardiac output (CO) and blood flow to the placenta. Fluid preloading with crystalloid is ineffective due to rapid redistribution. A "coload" given at the time of cerebrospinal fluid identification may be more effective. Our null ...

Propofol anesthesia may induce metabolic disturbances and sevoflurane anesthesia arterial hypotension. This study compares both techniques regarding acid-base and hemodynamic status during intracranial surgery. Sixty-one patients were randomized into 2 groups according to anesthesia maintenance, a propofol group (n=30), and a sevoflurane group (n=31). The anesthesia protocol including rocuronium and ...

We hypothesized that like bispectral index, entropy may be anesthetic agent specific. We carried out a study to assess the entropy values of different anesthetics at equi-minimal alveolar concentrations (MACs) with air and nitrous oxide as carrier gases. Thirty adult patients undergoing spine surgery were randomized to receive halothane, isoflurane, ...

The present study was conducted to evaluate the effect of scalp infiltration with Bupivacaine on hemodynamic responses during early stimulation in craniotomy under general anesthesia. Thirty six patients were prospectively randomized to receive Bupivacaine scalp infiltration (B group) or a saline control (S group) as an adjuvant to general anesthesia ...

AIM: To investigate the electroencephalographic (EEG) and cardiovascular responses of halothane-anaesthetised calves to non-penetrative captive-bolt stunning. METHODS: Ten calves were minimally anaesthetised with halothane, using an established anaesthesia protocol. The EEG, blood pressure and electrocardiogram (ECG) were recorded before and after non-penetrative captive-bolt stunning. Visual inspection and alterations in the ...

OBJECTIVE: To determine risk factors for developing hypotension after spinal anesthesia for cesarean section to prevent obstetric patients from hypotensive episodes potentially resulting in intrauterine malperfusion and endangering the child. METHODS: The data from 503 women, having received spinal anesthesia for cesarean sections were investigated using online gathered vital signs ...

PURPOSE: To evaluate and describe immediate effects of the infusion of saline solution heated by SAF in bitches submitted to halothane anesthesia. METHODS: Thirteen bitches were employed and submitted to elective ovariohysterectomy in acclimatized operating room at 22 degrees C, allocated in two groups: GI, which received non-heated fluid and ...

BACKGROUND: Pre-loading with hetastarch decreases the incidence and severity of hypotension after spinal anesthesia for cesarean delivery. However, pharmacokinetic studies with crystalloid predict that fluid loading should be more efficacious if rapidly administered immediately after induction of spinal anesthesia. The aim of this study was to compare pre- and co-loading ...

OBJECTIVE: The anaesthetic conserving device (AnaConDa), Sedana Medical, Sundbyberg, Sweden) facilitates administration of isoflurane or sevoflurane by liquid infusion. An anaesthetic reflector inside the device conserves exhaled anaesthetic and re-supplies it during inspiration. In this bench study, we examined the influence of infusion rates and ventilatory settings on the resulting ...

To determine if the preanesthetic administration of ephedrine would prevent anesthesia-induced hypotension in dogs and cats, 10 cats were anesthetized with acepromazine, butorphanol, ketamine, and isoflurane, and 8 dogs were anesthetized with acepromazine, morphine, propofol, and halothane. Cats received ephedrine or saline 10 minutes after premedication. Dogs received ephedrine or ...

Isoflurane is the most commonly used anesthetic in mice. We studied the effect of low and high levels of isoflurane (also a potent coronary vasodilator) on aortic impedance in mice. Aortic impedance was determined using pressure and flow velocity signals at baseline (B, pentobarbital anesthesia), low (Isol, 1%), and high ...

General anesthesia causes peripheral vasodilation. We thus hypothesized that patients with increased peripheral vascular tone would become more hypotensive after the induction of general anesthesia compared to those without increased peripheral vascular tone. To test this hypothesis, we compared the decrease in blood pressure after anesthetic induction between patients with ...

To develop an experimental model and evaluate the effects of the magnitude and duration of pressure, the rat abdominal wall (25x20 mm) was subjected to compression either by a weight or by two magnets. In the weight compression tests, a steel plate was inserted under anesthesia into the rat peritoneal ...

OBJECTIVE: To assess cardiac and hemodynamic responses and body temperature during long-term general anesthesia using sevoflurane/fentanyl after premedication with a tiletamine/zolazepam/medetomidine combination in swine undergoing experimental pancreas transplantation. MATERIALS AND METHODS: Twelve Landrace female pigs of means weight 46.4 +/- 5.1 kg were premedicated by intramuscular administration of tiletamine/zolazepam (3.5 ...

Some properties of the volatile anesthetics, such as vasodilatation and myocardial depression, combined with the sympathetic inhibition that alpha2-agonists can produce, may determine hemodynamic alterations during aortic surgery. The interaction between dexmedetomidine (DEX), an alpha2-agonist, and sevoflurane during aortic surgery is unknown. We studied the effects of DEX on hemodynamics ...

Free-ranging Hoffmann's two-toed sloths (Choloepus hoffmanni; n=26) and brown-throated three-toed sloths (Bradypus variegatus; n=15) were manually captured and immobilized with 2.5 mg/kg ketamine + 0.02 mg/kg medetomidine administered intramuscularly. Physical examinations were conducted on each sloth 10 min after initial injection, and blood, fecal, and ectoparasite samples were collected. Heart ...

GOALS: The aim of this study is to compare the efficacy of HES 130/0.4, a new hydroxyethyl starch, to lactated Ringer's solution (LR) in the prevention of hypotension after spinal anesthesia for cesarean section (CS). MATERIAL AND METHODS: One hundred and twenty nonlaboring ASA I and II women having non ...

OBJECTIVE: To determine the effect of inhalation of isoflurane at end-tidal concentrations greater than, equal to, and less than the minimum anesthetic concentration (MAC) on bispectral index (BIS) in chickens. Animals-10 chickens. PROCEDURES: For each chicken, the individual MAC of isoflurane was determined by use of the toe-pinch method. After ...

BACKGROUND: Combination of epidural and general anesthesia (combined anesthesia) avoids the intraoperative use of intravenous analgesics and may reduce the surgical stress response during major abdominal surgery. This study examines the differences in intraoperative hemodynamic stability, cortisol levels and activity of cardiovascular hormones between combined anesthesia and isoflurane/fentanyl anesthesia. MATERIAL/METHODS: ...

BACKGROUND AND OBJECTIVE: The reliability of the Bispectral Index for evaluating and monitoring the depth of general anaesthesia in children is not as great as for that in adults. Therefore we analysed Bispectral Index performance in children by comparing changes in Bispectral Index values during a standardized and equipotent anaesthetic ...

BACKGROUND AND OBJECTIVES: Side effects of spinal anesthesia include arterial hypotension and bradycardia. Both of them may be induced by sympathetic nerve blockade as well as by the Bezold-Jarisch reflex, which may be mediated by peripheral serotonin receptors (5-HT(3) type). The aim of this study was to verify the hypothesis ...

OBJECTIVES: To evaluate the hemodynamic responses to nociceptive stimuli in children submitted to videolaparoscopic appendectomy under balanced anesthesia with isoflurane and dexmedetomidine. METHODS: Randomized, double-blind and placebo-controlled study involving 26 children submitted to videolaparoscopic appendectomy carried out at Hospital São Lucas (PUCRS) between May 2004 and February 2005. Patients were ...

OBJECTIVE: The present study consists of a double-blind randomized clinical trial of paired samples. The purpose of the present study was thus to examine the effect of four different local anesthetics of the amida group (2% lidocaine with 1:100.000 adrenaline; 3% prilocaine with 0.30 IU felipressine; 2% mepivacaine with 1:100.000 ...

INTRODUCTION: Drug-induced cardiovascular effects identified in conscious cynomolgus monkeys equipped with tethers and prepared for radiotelemetry were compared with results from anesthetized non-human primate (cynomolgus and rhesus) models. METHODS: Remifentanil (4.0 microg/kg, bolus), esmolol (2.0 mg/kg, bolus) and dopamine (0.05 mg/kg/min, 30 min infusion) were given intravenously to all models. ...

Introduction: Maintaining normal blood pressure (BP) in pregnant patients is important for normal placental blood flow and to avoid undesirable symptoms. Despite our practice to maintain normal baseline BP, hypotension remains the most common complication during Cesarean delivery under spinal anesthesia. We hypothesize that continuous monitoring of several cardiovascular hemodynamics ...

BACKGROUND: Autonomic hyperreflexia (AHR) is a potentially life-threatening hypertensive condition that occurs in patients with high spinal cord injury (SCI). The current study was aimed to determine sevoflurane concentrations that block AHR in SCI patients. METHODS: The study involved 28 patients with chronic, complete SCI scheduled to undergo transurethral litholapaxy ...

BACKGROUND: Anesthesia impairs upper airway integrity, but recent data suggest that low doses of some anesthetics increase upper airway dilator muscle activity, an apparent paradox. The authors sought to understand which anesthetics increase or decrease upper airway dilator muscle activity and to study the mechanisms mediating the effect. METHODS: The ...

The rate of anaesthetic gas uptake from the breathing system has been extensively measured, but this does not reflect the true rate of early gas uptake by pulmonary blood, which drives inhalational induction of anaesthesia. In eight patients undergoing coronary bypass surgery, we measured the rate of alveolar-capillary uptake of ...

Equilibration between delivered and effect site anesthetic partial pressure is slow in frogs. The use of less soluble agents or overpressure delivery may speed equilibration. Ten Northern leopard frogs were exposed to 3-4 constant concentrations of halothane, isoflurane or desflurane and their motor response to noxious electrical stimulation of the ...

BACKGROUND AND OBJECTIVES: Adrenomedullin is a potent vasodilatory peptide. The mechanisms of adrenomedullin-induced responses are via guanine nucleotide guanosine 5'-triphosphate-binding protein (G-protein)-coupled receptor activation and are similar to those of calcitonin gene-related peptide (CGRP). Previously, we reported that sevoflurane and isoflurane inhibit CGRP-induced haemodynamic responses. The effects of volatile anaesthetics ...

BACKGROUND: The aim of the present study was to examine the level of unconsciousness measured with bispectral index (BIS) at different minimal alveolar concentration (MAC) levels of sevoflurane, and to study the hemodynamic and BIS reactions during noxious stimulation with transcutaneous electrical nerve stimulation (TENS) and an ice water pain ...

OBJECTIVE: To determine whether infusion of xylazine (XYL) and ketamine (KET) for 30 minutes after isoflurane administration in horses would result in improved quality of recovery from anesthesia, without detrimental cardiopulmonary changes. STUDY DESIGN: Randomized, blinded experimental trial. ANIMALS: Seven healthy adult horses aged 6.4 +/- 1.9 years and weighing ...

BACKGROUND: One of the hazards of general anesthesia for cesarean section (C/S) is the risk of intraoperative awareness with or without recall of the event. We examined the relationship between auditory evoked potential index (AAI), end-tidal isoflurane concentration and hemodynamic parameters to evaluate the adequacy of our routine general anesthetic ...

OBJECTIVE: To assess physiologic responses and plasma endothelin (ET)-1 concentrations associated with abrupt cessation of nitric oxide (NO) inhalation in isoflurane-anesthetized horses. ANIMALS: 6 healthy adult Standardbreds. PROCEDURES: Horses were anesthetized with isoflurane in oxygen and placed in dorsal recumbency. Nitric oxide was pulsed into the respiratory tract for 2.5 ...

OBJECTIVE: To compare the effect of remifentanil combined with desflurane or isoflurane on the quality of the operative field and surgical conditions, blood loss, and recovery during tympanoplasty or endoscopic sinus surgery. DESIGN: Randomised, double-blinded clinical study. SUBJECTS: Sixty-four patients were scheduled for elective tympanoplasty or endoscopic sinus surgery. The ...

We report Raman spectroscopic studies of the nanosized rare earth sesquioxides, namely yttrium sesquioxide (Y(2)O(3)), gadolinium sesquioxide (Gd(2)O(3)) and samarium sesquioxide (Sm(2)O(3)), under high pressure. The samples were characterized using x-ray diffraction, Raman spectroscopy and atomic force microscopy at atmospheric pressures. Y(2)O(3) and Gd(2)O(3) were found to be cubic at ...

OBJECTIVE: To determine the haemodynamic effects of halothane and isoflurane with spontaneous and controlled ventilation in dorsally recumbent horses undergoing elective surgery. STUDY DESIGN: Prospective randomized clinical trial. ANIMALS: Twenty-five adult horses, body mass 487 kg (range: 267-690). METHODS: Horses undergoing elective surgery in dorsal recumbency were randomly assigned to ...

We report the use of a balanced anesthetic technique in a three-year-old, female Huacaya alpaca with an increased anesthetic risk that underwent an extensive dental surgery. Anesthesia was provided with an infusion of midazolam, fentanyl, S-ketamine and low concentrations of isoflurane in oxygen. The mandibular alveolar nerve was desensitized with ...

BACKGROUND: Hypotension or bradycardia after spinal anesthesia for cesarean section remain common and are serious complications. The current study evaluated factors associated to the incidences of hypotension or bradycardia in this context. MATERIAL AND METHOD: A prospective cross sectional study from November 1, 2004 to July 31, 2005 was conducted ...

STUDY OBJECTIVE: To compare the cardiovascular effects of isoflurane and sevoflurane at minimum alveolar concentration (MAC) = 1 in children with congenital heart disease using cardiac magnetic resonance imaging. DESIGN: Randomized, crossover, single-blinded study. SETTING: Tertiary-care teaching hospital. PATIENTS: 10 pediatric patients with congenital heart diseases scheduled to undergo cardiac ...