No abstract available.

BACKGROUND: We have previously demonstrated the isoflurane and halothane may be detrimental to in vitro fertilization of mouse oocytes in high concentrations. The aim of this study is to compare the toxic effects of volatile anesthetics on mouse embryos using in vitro growth model of two cell mouse embryos. METHODS: Mouse two-cell embryos exposed to three volatile anesthetics, enflurane(0.5 mM; 1.5 mM), isoflurane(0.26 mM; 0.78 mM) and halothane(0.24 mM; 0.72 mM). Mouse two-cell embryos unexposed to any drugs were included as controls. RESULTS: The percentages of two-cell mouse embryos developed over morula stages on the third day after exposure of high concentrations of isoflurane and halothane decreased significantly compared with controls. The rates of embryos arrested at 2-8 cell stage in these groups were significantly higher than that of controls. There were no significant differences in these rates between enflurane group, isofiurane and halothane group of lower concentrations and controls. The hatching and/or hatched blastocysts development were significantly lower in isoflurane and halothane group than in controls. No significant differences in the hatching rate of blastocyst developed were observed among groups. CONCLUSIONS: Our data show that isoflurane and halothane in high concentrations have harm effects of the in vitro growth of two cell mouse embryos.
Anesthesia* ; Anesthetics ; Animals ; Blastocyst ; Embryonic Development ; Embryonic Structures ; Enflurane ; Female ; Fertilization in Vitro ; Halothane ; Isoflurane ; Mice ; Morula ; Oocytes ; Pregnancy

BACKGROUND: We have previously demonstrated the isoflurane and halothane may be detrimental to in vitro fertilization of mouse oocytes in high concentrations. The aim of this study is to compare the toxic effects of volatile anesthetics on mouse embryos using in vitro growth model of two cell mouse embryos. METHODS: Mouse two-cell embryos exposed to three volatile anesthetics, enflurane(0.5 mM; 1.5 mM), isoflurane(0.26 mM; 0.78 mM) and halothane(0.24 mM; 0.72 mM). Mouse two-cell embryos unexposed to any drugs were included as controls. RESULTS: The percentages of two-cell mouse embryos developed over morula stages on the third day after exposure of high concentrations of isoflurane and halothane decreased significantly compared with controls. The rates of embryos arrested at 2-8 cell stage in these groups were significantly higher than that of controls. There were no significant differences in these rates between enflurane group, isofiurane and halothane group of lower concentrations and controls. The hatching and/or hatched blastocysts development were significantly lower in isoflurane and halothane group than in controls. No significant differences in the hatching rate of blastocyst developed were observed among groups. CONCLUSIONS: Our data show that isoflurane and halothane in high concentrations have harm effects of the in vitro growth of two cell mouse embryos.
Anesthesia* ; Anesthetics ; Animals ; Blastocyst ; Embryonic Development ; Embryonic Structures ; Enflurane ; Female ; Fertilization in Vitro ; Halothane ; Isoflurane ; Mice ; Morula ; Oocytes ; Pregnancy

No abstract available.
Anesthesia, General* ; Humans ; Laryngeal Masks* ; Pierre Robin Syndrome*

Acute hyperkalemia may result from many causes, i.e. excessive load, transcellular shift, decreased renal excretion, and so on, and may be associated with irreversible and fatal cardiac manifestations, muscle weakness, ventilatory and adrenal insufficiency, etc. We experienced a case of acute hyperkalemia probably due to red cell lysis which was evident immediately after the induction of general anesthesia with thiopental sodium and succinylcholin in 1 33 year-old female patient with common bile duct obstructive jaundice. In spite of active management during anesthesia and posoperative period, eventually she died of cardiac arrest. For the successful management of the acute hyperkalemia, the anesthesiologist should be aware of its etiologies, pathophysiology, diagnosis & treatment.
Adrenal Insufficiency ; Adult ; Anesthesia ; Anesthesia, General* ; Common Bile Duct ; Diagnosis ; Female ; Heart Arrest ; Humans ; Hyperkalemia* ; Jaundice, Obstructive ; Muscle Weakness ; Thiopental

BACKGROUND: The position for tracheal intubation using direct laryngoscopy is extension of the head with flexion of the neck, the classical 'sniffing position'. If necessary, an extra pillow can be used to keep the neck flexed. By adopting this position the oral, pharyngeal, and laryngeal axes is a almost straight line to facilitate tracheal intubation. Also, this position is ideal for conventional laryngeal mask airway (LMA) insertion. However, insertion of intubating laryngeal mask airway (ILM) and intubation through ILM may be achieved from any position relative to the patient's head. As recommended by the manufacturer, when possible a pillow should be placed under the head to achieve a neutral position. The purpose of this study was therefore to compare the easiness of intubation through ILM without support and with the patient's head supported by a pillow. METHODS: After acquiring informed consent, 80 ASA grade 1 or 2 patients undergoing general anesthesia for elective surgical procedures who normally required tracheal intubation were randomized into two groups. In group 1 (n = 40), insertion of ILM and intubation was conducted with the head supported by a pillow, while there was no support in group 2 (n = 40). The patients were induced and relaxed with an IV injection of thiopental sodium, fentanyl-ketamine-midazolam mixture and vecuronium. When adequate level of anesthesia was achieved, the ILM was inserted. After adequate ventilation was confirmed, a blind tracheal intubation through the ILM was attempted. Then we recorded success rate, insertion time, intubation time and adjusting maneuvers. RESULTS: The ILM was successfully inserted on the first attempt in 79/80 patients, but 1 patient of group 1 failed to be adequately ventilated. The mean time for ILM insertion of group 2 was shorter than that of group 1. The success rate of tracheal intubation was 37(95%) in group 1 and 40 (100%) in group 2. In group 1, 30 (81%) patients were successfully intubated on the first attempt, 1 (3%) patient on the second attempt, and 6(16%) patients on the third attempt; in group 2, 35 (87%) patients on the first attempt, and 5 (13%) patients on the third attempt. There was no significant diffrence of mean time taken for endotracheal intubation through ILM between group 1 (105.1 sec) and group 2 (88.1 sec). CONCLUSIONS: The authors conclude that ILM insertion is significantly easier with the patient's head not supported by a pillow compared with the patient's head supported by a pillow and there is no difference in ease of intubation through ILM by the patient's head position.
Anesthesia ; Anesthesia, General ; Head* ; Humans ; Informed Consent ; Intubation* ; Intubation, Intratracheal ; Laryngeal Masks ; Laryngoscopy ; Masks* ; Neck ; Surgical Procedures, Elective ; Thiopental ; Vecuronium Bromide ; Ventilation

BACKGROUND: The larynx is longitudinally stretched and anteriorly displaced by inducing the general anesthesia and muscle paralysis, thus the laryngoscopic visualization might become difficult during direct laryngoscopy. The study was designed to assess the efficacy of the "laryngeal lift" maneuver in improving the laryngoscopic visualization to facilitate tracheal intubation. METHODS: Following the induction of general anesthesia and muscle paralysis, the laryngoscopic views of 287 patients were evaluated while the laryngeal lift by which the cricoid cartilage was displaced 0.5 cm posteriorly and 1.0~1.5 cm cephaladly were performed. One hundred and three patients with grade 2-4 laryngoscopic veiw were analysed. The laryngoscopic view which was described by Cormack and Lehane was classified from grade 1 to grade 4. The postoperative complications such as dysphasia and/or dyspnea were also observed. RESULTS: Seventy four patients of 81 patients with the laryngoscopic view of grade 2 were improved by one grade. Twenty one patients of 22 patients with the laryngoscopic view of grade 3 were improved by more than one grade. However, the laryngoscopic views of eight patients out of 103 patients were not improved. The tracheal intubation was successful in all patients. The overall, grade 2 and grade 3 improvement rate of laryngoscopic view was 92.2%, 91.4% and 95.5% respectively. The improvement rate by one grade and two grade was 89.3% and 2.9% respectively. CONCLUSIONS: The laryngeal lift had the high improvement rates of laryngoscopic view without any complications. Thus it is concluded that the laryngeal lift is a useful maneuver for improving laryngoscopic view during direct laryngoscopy with curved blade of laryngoscope.
Anesthesia, General ; Aphasia ; Cricoid Cartilage ; Dyspnea ; Humans ; Intubation ; Intubation, Intratracheal* ; Laryngoscopes ; Laryngoscopy ; Larynx ; Paralysis ; Postoperative Complications

BACKGROUND: The conventional laryngeal mask airway (LMA) has been used to facilitate blind tracheal intubation in numerous situations where laryngoscopy and conventional intubation has been difficult, but it has the disadvantage that its airway tube is too long and narrow for intubation. The intubating laryngeal mask airway (ILM) has been specifically designed to increase the success rate of blind intubation. A specially constructed ILM tracheal tube is available for use with the ILM, But this tube is in short supply and expensive. Thus, this study was performed to compare the success rate and time of blind intubation through ILM with reinforced tracheal tube or specially-designed tracheal tube, and to assess the use of reinforced tracheal tube as a substitute for specially-designed tracheal tube. METHODS: After acquiring informed consent, 60 ASA grade 1 or 2 patients undergoing anesthesia for elective surgical procedures who normally required tracheal intubation were randomized into two groups. In group 1 (n = 30), the patients were intubated with a specially-designed tracheal tube through ILM. In group 2 (n = 30), reinforced tracheal tubes were used. The patients were induced and relaxed with an iv injection of thiopental sodium, fentanyl-ketamine-midazolam mixture and vecuronium. When an adequate level of anesthesia was achieved, the ILM was inserted. After adequate ventilation was confirmed, blind tracheal intubation with either of the two types of tracheal tubes through the ILM was attempted. Then we recorded success rate, intubation time and adjusting maneuvers. RESULTS: The ILM was successfully inserted at first attempt in 59/60 (98%) patients, but in 1 patient, adequate ventilation was not acheived. The success rate of tracheal intubation was 27 (93%) in group 1 and 28 (93%) in group 2. In group 1, 21 (72%) patients were successfully intubated on the first attempt, 1 (4%) patient on the second attempt, and 5 (17%) patients on the third attempt. In group 2, 20 (67%) patients were successfully intubated on the first attempt, 2 (6%) patients on the second attempt, and 6 (20%) patients on the third attempt. The mean time taken for intubation was 116.9 sec in group 1 and 122.3 sec in group 2. CONCLUSIONS: The authors conclude that the reinforced tracheal tube can be substitute for a specially- designed tracheal tube.
Anesthesia ; Humans ; Informed Consent ; Intubation* ; Laryngeal Masks* ; Laryngoscopy ; Surgical Procedures, Elective ; Thiopental ; Vecuronium Bromide ; Ventilation

BACKGROUND: Bupivacaine is a potent, and commonly used, long acting local anesthetic. If accidentally injected into the systemic circulation, bupivacaine can cause lethal dysrhythmias and circulatory collapse. Attempts to treat bupivacaine induced cardiac toxicity have been varied and controversial, and they have not been very successful. The aim of this study was to investigate the electrophysiologic effects of bupivacaine in Purkinje fibers. METHODS: Effects of bupivacaine on the membrane potential were studied in 12 isolated canine Purkinje fibers. Purkinje fibers from ventricle were dissected and mounted in a tissue chamber perfused with Tyrode's solution. Transmembrane potentials recorded through glass microelectrodes filled with 3M KCI in the beating or quiescent Purkinje fibers during infusions of bupivacaine at concentratons of 3*10/-7M,10/-6M, 3*10/-6M,10/-5M, and 3*10/-5M. RESULTS: Bupivacaine reduced action potential druation in a dose-dependent manner. Bupivacaine produced a decrease in intracelullar sodium ion activity in driven(1Hz) and quiescent canine Purkinje fibers. Bupivacaine-induced hyperpolarizaton of diastolic membrane potential in quiescent Purkinje fibers was dose dependent, and the hyperpolarization by bupivacaine was attenuated by depolarization induced by high potassium extracellular concentration in part. CONCLUSIONS: These results suggest that bupivacaine decreases the fast inward sodium current, and inhibits pacemaker current in canine Purkinje fibers.
Action Potentials ; Bupivacaine* ; Glass ; Membrane Potentials* ; Membranes* ; Microelectrodes ; Potassium ; Purkinje Fibers ; Shock ; Sodium ; Sodium Channels

BACKGROUND: The laryngeal mask airway (LMA) should be correctly placed into the hypopharynx for adequate ventilation. The purpose of this study was to evaluate a LMA position relation to the laryngeal skeleton and narrowing degree of a LMA lumen by the epiglottis. METHODS: The LMA (# 3 or # 4) was placed into the hypopharynx after induction of anesthesia and muscle paralysis. The fiberoptic laryngoscopic findings through the lumen of LMA were recorded at ten minutes after LMA placements. The position of the LMA was estimated in relation to its distal aperture to the laryngeal skeleton as central, posterior, right and left lateral position. The narrowing degree of the LMA by the epiglottis was estimated as 0%, 1~25%, 26~50%, 51~75%, or 76~100%. RESULTS: The fiberoptic laryngoscope showed central positions in 70.1%, lateral deviations to the left or right in 21.2% and posterior positions in 9%. The most frequent incidence (84/231, 36.4%) of narrowing by the epiglottis is 76~100% but ventilating problems were not developed. However, ventilation was impossible immediately after LMA placement in one patient, so the LMA was removed and the trachea was intubated. Esophageal enterance was visible in one patient without regurgitation of the stomach content. CONCLUSIONS: These findings show that LMA provides a reliable and safe airway management technique, although inadequate positioning and narrowing of LMA lumen by the epiglottis may frequently occur.
Airway Management ; Anesthesia ; Epiglottis ; Gastrointestinal Contents ; Humans ; Hypopharynx* ; Incidence ; Laryngeal Masks* ; Laryngoscopes ; Paralysis ; Skeleton ; Trachea ; Ventilation