BACKGROUND: Although isoflurane has been shown to cause coronary and systemic vasodilation through KATP channel activation, the interaction of KATP channel openers and isoflurane has not been fully investigated. The present study was carried out to determine the haemodynamic actions of cromakalim, a KATP channel opener, under the conscious state ...

BACKGROUND: The aim of this study was to compare desflurane and isoflurane for spinal procedures requiring moderate levels of controlled arterial hypotension, when these agents were administered via a semi-closed circuit at 1 l x min(-1) fresh gas flow. METHODS: After ethics committee approval and written informed consent, 20 ASA ...

Eighty-five thoroughbred racehorses with various types of fracture were subjected to arthroscopic surgery (44 horses) or internal fixation (41 horses) under sevoflurane anesthesia. The mean end-tidal sevoflurane concentration during anesthesia ranged from 2.5 to 2.8%. PaCO2 was maintained between 50 and 65 mmHg by controlled ventilation. The mean arterial blood ...

BACKGROUND: Influences of isoflurane and esmolol on endotracheal intubation induced sympathetic changes could be different. The effect of isoflurane and its combination with esmolol on catecholamine, blood pressure and pulse during endotracheal intubation were investigated. METHODS: Thirty patients were anesthetized with 3.0% isoflurane and tracheal intubation was carried out at ...

Previous publications suggest that handwritten anesthesia records are less accurate when compared with computer-generated records, but these studies were limited by small sample size, unblinded study design, and unpaired statistical comparisons. Eighty-one pairs of handwritten and computer-generated neurosurgical anesthesia records were retrospectively compared by using a matched sample design. Systolic ...

A captive 590-kg (1,298-lb) 22-year-old castrated male Kodiak brown bear was evaluated because of a soft tissue mass in the right carpal and antebrachial regions. General anesthesia was deemed necessary on 3 occasions for various procedures including radiographic evaluation and biopsy, excision, and radiation treatment. The bear was given carfentanil ...

BACKGROUND: Bronchospasm is a potential complication in anyone undergoing general anesthesia. Because volatile anesthetics relax bronchial smooth muscle, the effects of two newer volatile anesthetics, desflurane and sevoflurane, on respiratory resistance were evaluated. The authors hypothesized that desflurane would have greater bronchodilating effects because of its ability to increase sympathetic ...

We investigated the hyperalgesic (antianalgesic) effect of the inhaled anesthetics isoflurane, halothane, nitrous oxide, and diethyl ether, or the nonimmobilizer 1, 2-dichlorohexafluorocyclobutane at subanesthetic partial pressures (or, for the nonimmobilizer, subanesthetic partial pressures predicted from lipid solubility) in rats. Hyperalgesia was assessed as a decrease in the time to withdrawal ...

BACKGROUND: Pulsus alternans is a classic type of abnormal pulse. It can be defined as a regular alternation of pulse amplitude in which runs of weak and strong beats follow each other alternatively without any change in cycle length. It may be a sign of severe decompensated congestive heart failure. ...

BACKGROUND: N-methyl-d-aspartate (NMDA) receptor antagonists are neuroprotective in animal models of cerebral ischemia, but adverse cardiovascular and neurobehavioral effects have precluded their clinical use. The authors present the neuroprotective, anesthetic, and cardiovascular effects of a novel NMDA antagonist, CNS 5161A. METHODS: Lambs, 4.0-6.5 kg, were anesthetized with isoflurane, intubated, and ...

Effects of sevoflurane and isoflurane anesthesia in oxygen on clinical, cardiopulmonary, hematological, and serum biochemical findings were compared in sheep breathing spontaneously undergoing minor surgical operations during short-term (60-80min) or long-term (3-4h) anesthesia. All sheep were premedicated with atropine sulfate (0.1mg/kg) intramuscularly, and 10min later, induced to anesthesia by intravenous ...

The cardiovascular effects of volatile anesthetics in prenatal hearts are not well investigated. The purpose of this study was to determine whether the embryonic cardiovascular system is sensitive to an exposure to clinically relevant, equipotent concentrations of halothane and isoflurane. Stage 24 (4-day-old) chick embryos were exposed to 0.09 and ...

The complexity of modern anesthesia procedures requires the development of decision-support systems functioning in a smart-alarm capacity. We developed computer algorithms to detect critical conditions during surgery (light anesthesia or unstable blood pressure), based on computerized anesthesia records containing hemodynamic data (heart rate, mean arterial pressure and systolic arterial pressure). ...

BACKGROUND: Sevoflurane is almost the idealest volatile anesthetic agent regarding inhalation induction of general anesthesia. Previous studies have established a role of sevoflurane in high concentration primed in the circuit for inhalation induction in pediatric patients. However, which concentration of sevoflurane is suitable has not yet been reported. This study ...

To evaluate the hemodynamic effects produced by intrathecal administration of oxytocin in healthy isoflurane-anesthetized dogs. Prospective single-dose trial. Six healthy purpose-bred adult dogs weighing between 7.3 and 14.5 kg. Dogs were anesthetized with isoflurane and instrumented. Oxytocin at a dosage of 1.6 microg/kg was administered intrathecally at the cisternal space ...

The effects of inhalational anaesthetic agents on renal sympathetic nerve activity (RSNA) were compared in anaesthetized rabbits. Concentrations of 6% desflurane, 1.2% isoflurane, and 2.4% enflurane increased mean RSNA up to 32, 36 and 44% while higher concentrations, of 12, 2.4 and 3.2% depressed it by 42, 83 and 5%, ...

Heart rate, occurrence of apnea, body temperature, quality of anesthesia and nest abandonment were compared during either propofol or isoflurane anesthesia of nesting female canvasback ducks (Aythya valisineria) at 15 to 18 days of incubation. One hundred eighteen canvasbacks were assigned randomly to three treatments so that nest abandonment could ...

The present study is designed to investigate the time-dependent effect of pentobarbital anesthesia on the baroreflex arterial pressure (AP) control system in rabbits. The overall AP control capacity of the baroreflex system was assessed with mean arterial pressure (MAP) responses to the rapid mild hemorrhage (2 ml/kg body weight) and ...

The effects of halothane, isoflurane, sevoflurane (0.5, 1 and 2 MAC) and pentobarbital (10(-5) M, 10(-4) M and 3 x 10(-4) M) on hypocapnia- and bicarbonate-induced constriction of isolated dog middle cerebral arteries were investigated in vitro. The isometric tension of isolated cerebral arterial rings was measured in an organ ...

We tested dexmedetomidine, an alpha(2) agonist that decreases heart rate, blood pressure, and plasma norepinephrine concentration, for its ability to attenuate stress responses during emergence from anesthesia after major vascular operations. Patients scheduled for vascular surgery received either dexmedetomidine (n = 22) or placebo (n = 19) IV beginning 20 ...

It is reported that high dose desflurane can increase brain tissue oxygen pressure (PtO2) in patients during cerebral aneurysm surgery. The purpose of this study was to determine whether high dose isoflurane anesthesia can produce a similar effect in dogs and the importance of cerebral perfusion pressure in mediating this ...

We studied cardiovascular effects of isoflurane in chickens during controlled ventilation. Following the determination of the minimal anesthetic concentration from the response to clamping of a digit, dose-related effect of isoflurane on heart rate and arterial pressure were studied. The minimal anesthetic concentration of isoflurane was 1.25 +/- 0.13% (mean ...

BACKGROUND: Previous studies reported that, contrary to local anesthesia, cataract surgery under inhalational anesthesia is associated with substantial adrenergic activation. We tested the hypothesis that total intravenous anesthesia (TIVA) with propofol and alfentanil produces less or comparable adrenergic activation during cataract surgery than local anesthesia. METHODS: Patients were randomly assigned ...

This study was designed to determine the detectability of a simulated IV test dose in children during administration of general anesthesia by using heart rate (HR), systolic blood pressure (SBP), and T wave criterion. Forty-two children (0.5-8 yr old) received an IV injection containing epinephrine 0.5 microg/kg and another IV ...

The anesthetic and cardiovascular effects of a combination of continuous intravenous infusion using a mixture of 100 g/L guaifenesin-4 g/L ketamine-5 mg/L medetomidine (0.25 ml/kg/hr) and oxygen-sevoflurane (OS) anesthesia (GKM-OS anesthesia) in horses were evaluated. The right carotid artery of each of 12 horses was raised surgically into a subcutaneous ...

PURPOSE: This study was designed to compare the effects of sevoflurane and isoflurane on Pao(2) and hemodynamic variables during one-lung ventilation (OLV) in surgical patients. METHODS: Twelve patients undergoing an esophageal procedure with thoracotomy for which a long period of OLV was required were studied using a randomized crossover design. ...

Maternal hypotension is a common problem during cesarean section under spinal anesthesia. We evaluated in a prospective observational study the influence of injection speed on maternal hypotension. Hyperbaric bupivacaine 10 mg, sufentanil 2 microg and morphine 200 microg (total volume 4 mL) were injected either quickly (<15 s) or slowly ...

Desflurane has several properties making it a desirable agent for use in electrophysiological studies (EPS) for diagnosis and treatment of cardiac dysrhythmias. We studied 47 children, mean age 12.8+/-4.6 years, mean weight 52.9+/-24.0 kg, with clinical history of supra- ventricular tachycardia (SVT) during EPS using desflurane in a crossover comparison ...

Cigarette smoke contains over 4000 substances, some of which are harmful to the smoker. Some constituents cause cardiovascular problems, increasing the blood pressure, heart rate, and the systemic vascular resistance. Some cause respiratory problems, interfering with oxygen uptake, transport, and delivery. Further, some interfere with respiratory function both during and ...

To determine the minimum anesthetic concentration for sevoflurane and effects of various multiples of minimum anesthetic concentration on arterial pressure and heart rate during controlled ventilation in chickens. Prospective experimental study. Seven healthy chickens, 6 to 8 months old, weighing 1.6 to 3.4 kg. A rebreathing, semiclosed anesthetic circuit was ...

Prolongation of the Q-T interval may be associated with polymorphic ventricular tachycardia known as torsade de pointes, syncope and sudden death. Existing data show that isoflurane prolongs the Q-T interval, whereas halothane shortens it. The aim of this study was to determine whether sevoflurane or propofol affects the Q-T interval. ...

We investigated the effect of halothane and sevoflurane on oxygenation during one lung ventilation (OLV) in 24 patients undergoing elective thoracic procedures. After induction with thiopentone, 4-5 mg/kg and morphine 0.1 mg/kg, suxamethonium 2mg/kg was administered to facilitate tracheal intubation with a double lumen tube. Anaesthesia was maintained with 1.5-3% ...

The purpose of this study was to observe the hemodynamic changes during surgical extraction of lower third molars induced by three local anesthetics solutions associated with different vasoconstrictors. A double-blind observational and longitudinal study was made of 45 healthy adult volunteers subjected to surgical removal of an impacted lower third ...

PURPOSE: Rapid increases in concentrations of isoflurane and desflurane in oxygen have been shown to increase sympathetic activity. The aim of this study was to determine whether concomitant administration of nitrous oxide would reduce these sympathomimetic effects of volatile anesthetics. METHODS: Eighty healthy patients in whom the trachea was intubated ...

OBJECTIVE: To determine if sevoflurane provides comparable hemodynamics and recovery characteristics to isoflurane in cardiac anesthesia. DESIGN: A prospective, crossover, dose-response study using sevoflurane and isoflurane before the start of surgery, followed by randomization to sevoflurane or isoflurane for surgery with blinded assessment for recovery. SETTING: Tertiary referral cardiac clinic ...

BACKGROUND: Sevoflurane is suggested as a suitable anesthetic agent for mask induction in adults. The authors recently found that hyperventilation during sevoflurane-nitrous oxide-oxygen mask induction is associated with cardiovascular hyperdynamic response. We tested the hypothesis that the hyperdynamic response can be explained by electroencephalography (EEG) findings. METHODS: Thirty women were ...

BACKGROUND: This study was design to assess clinical agitation, electroencephalogram (EEG) and autonomic cardiovascular activity changes in children during induction of anesthesia with sevoflurane compared with halothane using noninvasive recording of EEG, heart rate, and finger blood pressure. METHODS: Children aged 2-12 yr premedicated with midazolam were randomly assigned to ...

BACKGROUND: Effects of halothane and enflurane on ventricular conduction, anisotropy, duration and dispersion of refractory periods, and wavelengths were studied, and putative antiarrhythmic or arrhythmogenic properties on ventricles were discussed. METHODS: High-resolution epicardial mapping system was used to study the effects of 1, 3, and 5 vol% halothane and enflurane ...

OBJECTIVES: To evaluate the effects of halothane and isoflurane on cardiovascular function and serum total and ionized calcium concentrations in horses, and to determine whether administration of calcium gluconate would attenuate these effects. ANIMALS: 6 clinically normal adult Thoroughbreds. PROCEDURE: Catheters were inserted for measurement of arterial blood pressures, pulmonary ...

Although hemoglobin-based oxygen carriers (HBOC) are now being investigated, the effects of HBOC solutions during regional anesthesia have never been analyzed. Therefore, we investigated the hemodynamic changes after HBOC infusion during general anesthesia and thoracic epidural anesthesia. Sheep were assigned to three different groups: a) a control group with six ...

OBJECTIVE: To determine the cardiopulmonary and sedative effects of medetomidine hydrochloride in adult horses and to compare those effects with effects of an equipotent dose of xylazine hydrochloride. ANIMALS: 10 healthy adult female horses. PROCEDURE: 5 horses were given medetomidine (4 microg/kg of body weight, i.v.), and the other 5 ...

The inspired partial pressure of an anaesthetic is often used as an index of arterial partial pressure in small animal experiments. We have investigated the influence of anaesthetic solubility on the ratio of arterial to inspired partial pressure in 24 rats, allocated randomly to receive halothane, isoflurane or desflurane at ...

To establish the effect of the locomotor pattern on heart rate (HR) and plasma lactate (LA), 28 horses, 18 Andalusian (AN) and 10 Anglo-Arabian (AA), aged 3-4 years, were studied. After a warm-up period, the horses performed a four-step test at 5, 6, 7 and 8 m/s, covering 1000 m ...

BACKGROUND: Xenon is a noble gas with anesthetic properties currently under investigation for use in humans. This study was performed to evaluate whether xenon may trigger malignant hyperthermia in susceptible swine. METHODS: Nine malignant hyperthermia-sensitive swine (Pietrain) were initially anesthetized with pentobarbital and then ventilated with 70% xenon in oxygen ...

OBJECTIVE: To identify factors associated with various arterial partial pressures of oxygen (Pao2) in anesthetized horses. DESIGN: Retrospective study. ANIMALS: 1,450 horses anesthetized a total of 1,610 times with isoflurane or halothane. PROCEDURE: Anesthesia records, particularly results of blood gas analyses, were reviewed, and horses were grouped on the basis ...

OBJECTIVE: To characterize variables used to monitor rabbits during inhalation anesthesia. ANIMALS: 8 male New Zealand White rabbits. PROCEDURE: Rabbits were similarly anesthetized with halothane (HAL) or isoflurane (ISO) in a crossover study; half received HAL followed by ISO, and the protocol was reversed for the remaining rabbits. After induction, ...

PURPOSE: The effects of sevoflurane anesthesia on the interactions between heart rate, blood pressure and respiration were assessed using transfer function analysis. METHODS: Nine ASA 1 or 2 patients undergoing elective surgery were involved. They were paralysed and their lungs were mechanically ventilated during sevoflurane anesthesia. Instantaneous heart rate (IHR) ...

STUDY OBJECTIVE: To compare the pharmacokinetics and the speed of recovery after inhalation anesthesia with desflurane, sevoflurane, and isoflurane in elective surgery. DESIGN: Prospective, randomized study. SETTING: University medical center. PATIENTS: 30 ASA physical status I and II adults presenting for elective surgery. INTERVENTIONS: Anesthesia was induced with etomidate and ...

BACKGROUND: The authors tested the hypothesis that ketamine and propofol anesthesia would alter the magnitude of hypoxic pulmonary vasoconstriction compared with the conscious state. In addition, they assessed the extent to which cyclooxygenase pathway inhibition and adenosine triphosphate-sensitive potassium channel inhibition modulate hypoxic pulmonary vasoconstriction in the conscious state, and ...

BACKGROUND AND OBJECTIVES: The purpose of this prospective, randomized, double-blinded study was to compare the hemodynamic effects of 6% hetastarch with lactated Ringer's solution and to determine the main reasons for hemodynamic impairment following spinal anesthesia in elderly patients undergoing emergent hip surgery. METHODS: After receiving institutional approval and informed ...