AIM: To test if anesthetic procedures change the hemodynamic pattern in animals with experimental septic shock. METHODS: The effect of two anesthetics on systemic hemodynamic and skeletal muscle microcirculatory responses in high cardiac output live E. coli bacteremia was studied in rats and compared to the effect of two other ...

BACKGROUND: Suppression of hypertensive response to noxious stimulation by volatile anesthetics may be a result of suppression of the stimulation-induced norepinephrine response or that of the cardiovascular response to catecholamines, or both. The suppression of the cardiovascular response is established, but that of norepinephrine response has not been confirmed. The ...

We have compared the effects of sevoflurane and isoflurane on arterial oxygenation, heart rate and mean arterial pressure during one lung anaesthesia in a prospective, crossover study. We studied 28 patients undergoing oesophagogastrectomy, allocated alternatively to one of two groups. Patients in group I/S (n = 14) received 1 MAC ...

INTRODUCTION: We evaluated whether automated anesthesia information systems can be used to calculate reference limits (population-based "normal values") for vital signs. We considered four populations of women undergoing cesarean section: healthy under spinal anesthesia, healthy under general anesthesia, pre-eclamptic/eclamptic under spinal anesthesia, and pre-eclamptic/eclamptic under general anesthesia. METHODS: Reference limits ...

PURPOSE: Rapid increase in inspired isoflurane concentration increases heart rate and arterial blood pressure. To investigate whether the responses to isoflurane were elicited from stimulation of lower airway and/or lungs, haemodynamic responses to isoflurane administered after tracheal intubation were measured with or without endotracheal or intravenous administration of lidocaine. METHODS: ...

The effects of halothane and isoflurane followed by subsequent administration of vecuronium on the QT interval have been investigated during the induction of anaesthesia. Fifty-eight children, ASA I, without cardiovascular and electrolyte abnormalities and not receiving any medication were studied. Anaesthesia was induced with either halothane (n = 28) or ...

BACKGROUND: Hypoxic pulmonary vasoconstriction has an important role in human one-lung ventilation (OLV) in the lateral decubitus position under general anesthesia. During OLV, inhalational anesthesia may inhibit hypoxic pulmonary vasoconstriction and the decrease in arterial oxygenation. We studied the effect of isoflurane administration on arterial oxygen tension in chronic obstructive ...

PURPOSE: Calcitonin gene-related peptide (CGRP) produces vasodilatation, hypotension, and tachycardia. Tachycardia induced by CGRP may be due to sympathetic activation. Volatile anaesthetics attenuate activation of arterial baroreflexes. We examined the haemodynamic and endocrine effects of CGRP infusion (4 micrograms.kg-1) during anaesthesia with either enflurane or isoflurane in dogs. METHODS: Measurements ...

STUDY OBJECTIVE: To evaluate and compare the stress hormone responses during laparoscopic cholecystectomy during general anesthesia, general anesthesia supplemented by fentanyl, and general anesthesia combined with epidural anesthesia. DESIGN: Prospective, randomized clinical study. SETTING: Operating rooms at a municipal hospital. PATIENTS: 52 ASA physical status I and II patients. INTERVENTIONS: ...

Effects of prolonged sevoflurane, isoflurane and halothane anaesthesia in oxygen on clinical, cardiopulmonary, haematologic, and serum biochemical findings were compared in healthy, premedicated cats breathing spontaneously during 6 h of anaesthesia using rebreathing (semi-closed circuit) or non-rebreathing (Bain coaxial circuit) system. Recovery from anaesthesia with sevoflurane was more rapid than ...

OBJECTIVE: To evaluate anesthetic and cardiorespiratory effects of an intramuscular injection of a tiletamine-zolazepam-medetomidine combination in cheetahs. DESIGN: Prospective study. ANIMALS: 17 adult captive cheetahs. PROCEDURE: The anesthetic combination was administered intramuscularly via a dart. Induction quality, duration of lateral recumbency, duration of recovery, and quality of anesthetic reversal with ...

The rostral ventrolateral medulla (RVLM) controls the vascular system. It may contribute to postoperative hypertension observed upon emergence from anesthesia. This structure contains adrenergic cardiovascular neurons. Therefore, one question was addressed: does a change in RVLM catechol activity occur upon emergence from anesthesia? Halothane-anesthetized, paralyzed rats had their ventilatory, circulatory, ...

The anesthetic potency and cardiopulmonary effects of sevoflurane were compared with those of isoflurane and halothane in goats. The (mean +/- SD) minimal alveolar concentration (MAC) was 0.96 +/- 0.12% for halothane, 1.29 +/- 0.11% for isoflurane, and 2.33 +/- 0.15% for sevoflurane. Cardiopulmonary effects of sevoflurane, halothane and isoflurane ...

We tested the hypothesis that desflurane (DES) and isoflurane (ISO) produce similar effects on systemic and pulmonary hemodynamics and arterial oxygenation before, during, and after one-lung ventilation (OLV) in patients undergoing thoracotomy. After obtaining informed consent, anesthesia was induced with sodium thiopental or thiamylal, fentanyl, and vecuronium in 61 ASA ...

The rate of uptake of sevoflurane during clinical anaesthesia (1.3 MAC) was measured by computer-controlled injection of liquid anaesthetic into a closed breathing system. The cumulative uptake of sevoflurane was 4.8 ml, 7.4 ml, 9.5 ml and 11.5 ml at 30, 60, 90 and 120 min, respectively. The ratio of ...

The discovery of ether anesthesia made modern surgery possible. Successive improvements produced today's inhaled anesthetics, compounds that allow precise control over the anesthetic state without compromising safety. Such control extends to induction and maintenance of, and recovery from, anesthesia. The greatest emphasis is on the last, particularly the rapid recovery ...

We evaluated the effect of the fresh gas flow (FGF) rate and the anesthetic technique on the ability to control the acute hyperdynamic response to a specific surgical stimulus during surgery in 90 consenting ASA physical status I-III patients undergoing lower abdominal procedures. After the administration of midazolam 2 mg ...

The protective efficacy of halogenated anaesthetics on myocardial injury has never been compared during early reperfusion and late reperfusion in an in vivo animal model. We compared recovery of left ventricular function under isoflurane (0.5 MAC) and halothane (0.5 MAC) anaesthesia after a brief period of regional ischaemia (15 min) ...

PURPOSE: To test the hypothesis that thiopentone, propofol, and etomidate alter the coronary vascular effects of abruptly administered isoflurane. METHODS: Dogs (n = 6) received inspired isoflurane 5% in the presence of thiopentone (20 mg.kg-1 induction dose and 20 mg.kg-1.hr-1 infusion), propofol (5 mg.kg-1 induction dose and 40 mg.kg-1.hr-1 infusion), ...

We assessed the anesthetic properties of helium and neon at hyperbaric pressures by testing their capacity to decrease anesthetic requirement for desflurane using electrical stimulation of the tail as the anesthetic endpoint (i.e., the minimum alveolar anesthetic concentration [MAC]) in rats. Partial pressures of helium or neon near those predicted ...

We studied the time course of arterial hypotension and/or bradycardia requiring treatment during spinal anesthesia and compared the efficacy of i.v. fluid or vasoconstrictor administration for the prevention of these side effects. Patients (n = 1066) were randomly allocated to either a volume group (lactated Ringer's solution 15 mL/kg within ...

BACKGROUND: This study compared the respiratory effects of sevoflurane with those of halothane in anesthetized infants and young children. METHODS: Infants were randomized to receive 1 minimum alveolar concentration (MAC) halothane or sevoflurane in a mixture of nitrous oxide and oxygen. Anesthetic management included the use of a laryngeal mask. ...

BACKGROUND: Studies concerning the cerebrovascular effects of sevoflurane in patients with space-occupying lesions are few. This study was carried out as a dose-response study comparing the effects of increasing sevoflurane concentration (1.5% (0.7 MAC) to 2.5% (1.3 MAC)) on cerebral blood flow (CBF), intracranial pressure (ICP), cerebrovascular resistance (CVR), metabolic ...

During isoflurane anesthesia, an epinephrine-containing test dose produces unreliable heart rate (HR) responses with a high incidence of hypertension, whereas an isoproterenol-containing test dose results in a high incidence of hypotension. We designed this study to determine whether different combination doses of epinephrine and isoproterenol produce reliable HR changes without ...

PURPOSE: To compare patient outcomes for positive pressure ventilation (PPV) and spontaneous ventilation (SV) in non-paralysed patients with the LMA using either isoflurane or sevoflurane anaesthesia. METHODS: One hundred and sixty four adult patients were studied. Anaesthesia was with fentanyl/propofol and N2O 66% in O2 with 0.75 MAC isoflurane or ...

BACKGROUND: Increasing concentrations of desflurane result in progressive decreases in blood pressure (BP) and, unlike other currently marketed, potent volatile anesthetics, heightened sympathetic nervous system activity. This study aimed to determine whether baroreflex mechanisms are involved in desflurane-mediated sympathetic excitation. METHODS: Healthy volunteers were anesthetized with desflurane (n = 8) ...

The possibility of awareness during general anesthesia causes apprehension for the patient and the Certified Registered Nurse Anesthetist (CRNA). The goals of general anesthesia are to prevent the sensation of pain and produce a state of sedation, hypnosis, and unconsciousness so the patient will not remember the surgical procedure. An ...

Uptake of inhaled anesthetics may be measured as the amount of anesthetic infused to maintain a constant alveolar concentration of anesthetic. This method assumes that the patient absorbs all of the infused anesthetic, and that none is lost to circuit components. Using a standard anesthetic circuit with a 3-L rebreathing ...

OBJECTIVE: To assess the cardiovascular effects of the alpha2-adrenergic receptor agonist medetomidine in healthy cats anesthetized with 2% isoflurane. ANIMALS: 11 clinically normal cats. PROCEDURE: Cats were anesthetized with isoflurane, and catheters were inserted for measurement of aortic, left ventricular, and right atrial pressures. For data collection, end-tidal isoflurane concentration ...

Nicorandil, a new KATP channel opener, is used in clinical practice for anti-anginal therapy. It exhibits vasodilator properties as does the halogenated anaesthetic isoflurane. We have examined the cardiovascular effects of increasing concentrations of isoflurane after administration of nicorandil in 10 adult beagle dogs anaesthetized with thiopental and whose lungs ...

BACKGROUND: The objective of this study was to investigate the effects of sevoflurane and desflurane anesthesia on the pulmonary vasodilator response to the adenosine triphosphate-sensitive potassium channel agonist, lemakalim, compared with the response measured in the conscious state. In addition, the authors assessed the extent to which sympathetic alpha1-adrenoreceptor inhibition ...

The isoflurane-saving and CO2-retaining effects of a charcoal filter were compared with a Siemens standard heat and moisture (HME) exchanger and an emptied specimen (dummy). Isoflurane was delivered during the inspiratory phase and consumption investigated at 10, 15 and 25 cycles min-1. The investigation was performed by ventilation with humidified ...

BACKGROUND: The new inhalational anesthetic sevoflurane would be expected to provide a rapid emergence from anesthesia due to its low blood/gas partition coefficient. In this study, we compared the hemodynamic effects, speed and quality of emergence, in ASA class I-II Chinese adult surgical patients receiving either sevoflurane or isoflurane anesthesia. ...

A spreadsheet model of a circle breathing system and a 70-kg anaesthetised 'standard man' has been used to simulate the first 20 min of low-flow anaesthesia with halothane, enflurane, isoflurane, sevoflurane and desflurane in oxygen. It is shown that, with the fresh-gas flow set initially equal to the total ventilation ...

OBJECTIVE: To determine the extent of neurogenic control on adrenal secretion in a canine model of high spinal anesthesia and cardiac arrest. DESIGN: Randomized, controlled, acute intensive study. SETTING: University intensive care laboratory. SUBJECTS: Nineteen healthy, anesthetized, mongrel dogs. INTERVENTIONS: Cardiac arrest was induced in 11 spinally anesthetized dogs and ...

BACKGROUND: In paediatric healthy patients and in real peroperative conditions, the cardiovascular effects of isoflurane have been poorly described. METHODS: We have evaluated the myocardial effects of 1% end-expired concentration (EEC) of isoflurane in 25 healthy infants or small children undergoing superficial surgical therapy for small burns with a continuous ...

The study investigated the stimulus to pituitary-adrenocortical activity (PACA) during halothane anaesthesia. Groups of six sheep were anaesthetized with thiopentone/halothane (TH group), acepromazine/thiopentone/halothane (ATH group) or pentobarbitone (P group). Dobutamine was infused in the TH and ATH groups to prevent hypotension (0.3-1.4 micrograms/kg/min) and in the P group at 0.05 ...

We have studied the cardiovascular effects of equipotent concentrations of halothane or isoflurane, with or without 50% nitrous oxide in oxygen, in 80 patients, aged 60 yr or more, during 20 min of stable equipotent anaesthesia. Non-invasive measurement techniques were used, with suprasternal Doppler ultrasonography for estimating cardiac output. Both ...

OBJECTIVE: To determine the cardiopulmonary effects of anesthesia induced and maintained with isoflurane (ISO) in cats. ANIMALS: 8 healthy cats between 1 and 5 years old. PROCEDURE: Anesthesia was induced with ISO in oxygen. Two anesthetic depths were maintained in each cat; mean alveolar concentrations (MAC) were 1.3 and 2.0 ...

STUDY OBJECTIVE: To compare cardiovascular stability during carotid endarterectomy in groups managed either with laryngeal mask airway (LMA) or endotracheal intubation. DESIGN: Randomized, retrospective, blinded study. SETTING: Teaching hospital. PATIENTS: 61 ASA physical status II, III, and IV unpremedicated adult males scheduled for carotid endarterectomy. INTERVENTIONS: Following standardized anesthetic technique, ...

A mathematical model derived from physiological considerations for the combined effects of anesthetic gas and surgical stimulation on mean arterial blood pressure (MAP) is proposed. A rough validation is done by comparing clinical MAP responses to responses of the model to a relatively well defined stimulus. Keywords--- physiological modeling, pain ...

BACKGROUND: Isoflurane protects against reperfusion injury in isolated hearts when given before, during, and initially after hypoxia or ischemia and aids in preconditioning hearts if given before ischemia. The aims of the current study were to determine if isoflurane is cardioprotective during 1-day, severe hypothermic perfusion and if a mechanism ...

BACKGROUND: Pituitary-adrenal secretion during induced hypotension for middle-ear surgery has received little attention. Previous work failed to differentiate the effects of induced hypotension from surgical stimulation. We have undertaken a preliminary study examining the effects of hypotension, achieved with labetalol or isoflurane, on pituitary-adrenal secretion before, during and after middle-ear ...

Cardiovascular, pulmonary, and quantitative electroencephalographic parameters were assessed in 12 anesthetized dogs to determine the compatibility of the injectable anesthetic propofol with halothane and isoflurane. No cases of apnea were observed during induction of anesthesia. An adequate level of anesthesia was established in each protocol as judged by both the ...

Safety in spinal anesthesia for cesarean section is achieved by strict adherence to the cardinal principles of proper evaluation and selection of patients, the use of prophylactic vasopressors, preanesthetic establishment of a reliable intravenous channel, small doses of the local anesthetic, close monitoring and maintenance of systolic blood pressure above ...

We measured the arterial blood pressure and percutaneous O2 saturation (SpO2) in 39 elderly patients (age range, 70-89 years) who underwent cataract surgery under local anesthesia. Nineteen patients showed a 20% or greater increase in the systolic arterial pressure (SAP) measured every minute in the operating room compared to the ...

The physical properties of sevoflurane suggest that it may be a suitable agent for controlled hypotension. With its low blood:gas partition coefficient of 0.69, it has a rapid onset of action making it easy to rapidly control blood pressure. The current report outlines preliminary experience with sevoflurane for controlled hypotension ...

OBJECTIVE: To determine whether a low dose of atropine is associated with decreased requirement for cardiovascular supportive treatment in horses given detomidine prior to maintenance of general anesthesia with halothane. ANIMALS: 3 groups of 10 healthy horses. PROCEDURE: Detomidine (20 micrograms/kg of body weight, i.m.) was administered to all 30 ...

Cardiopulmonary and acid-base variables recorded during long-term balanced anesthesia lasting between 12.5 and 16.9 h were evaluated retrospectively in 15 healthy foxhounds that underwent experimental bulla osteotomy with implantation of hearing aids. After premedication with propionylpromazine (0.11 +/- 0.02 mg/kg of body weight) and L-methadone (0.71 +/- 0.06 mg/kg) intravenously ...

To better characterize alterations in autonomic function associated with prolonged anesthesia, we tested the hypothesis that the time-dependent effects of sevoflurane and desflurane differ. We studied seven male volunteers, each anesthetized for 8 h with 1.25 minimum alveolar anesthetic concentration desflurane on one study day and with 8 h sevoflurane ...