PURPOSE: To characterize the electromyographic activity of abdominal striated muscles during micturition in urethane-anesthetized female mice, and to quantitatively evaluate the contribution of abdominal responses to efficient voiding. METHODS: Cystometric and multichannel electromyographic recordings were integrated to enable a comprehensive evaluation during micturition in urethane-anesthetized female mice. Four major abdominal muscle domains were evaluated: the external oblique, internal oblique, and superior and inferior rectus abdominis. To further characterize the functionality of the abdominal muscles, pancuronium bromide (25 μg/mL or 50 μg/mL, abdominal surface) was applied as a blocking agent of neuromuscular junctions. RESULTS: We observed a robust activation of the abdominal muscles during voiding, with a consistent onset/offset concomitant with the bladder pressure threshold. Pancuronium was effective, in a dose-dependent fashion, for partial and complete blockage of abdominal activity. Electromyographic discharges during voiding were significantly inhibited by applying pancuronium. Decreased cystometric parameters were recorded, including the peak pressure, pressure threshold, intercontractile interval, and voiding duration, suggesting that the voiding efficiency was significantly compromised by abdominal muscle relaxation. CONCLUSIONS: The relevance of the abdominal striated musculature for micturition has remained a topic of debate in human physiology. Although the study was performed on anesthetized mice, these results support the existence of synergistic abdominal electromyographic activity facilitating voiding in anesthetized mice. Further, our study presents a rodent model that can be used for future investigations into micturition-related abdominal activity.
Abdominal Muscles* ; Animals ; Electromyography ; Female* ; Humans ; Lower Urinary Tract Symptoms ; Mice* ; Muscle, Striated ; Neuromuscular Junction ; Pancuronium ; Physiology ; Rectus Abdominis ; Relaxation ; Rodentia ; Urinary Bladder ; Urination*

Pheochromocytoma is an uncommon tumor that originates in the adrenal medulla or in other paraganglia of the sympathetic nervous system. If a hypertensive crisis occurs during general anesthesia in incidental or untreated pheochromocytoma, it is a life-threatening event with a mortality rate of about 80%. Anesthetic drugs such as pancuronium, atracurium, and metoclopromide can exacerbate the potentially lethal cardiovascular effects of catecholamines. We report a case of a patient with pheochromocytoma who display abrupt increases in systolic arterial pressure and plasma norepinephrine following rocuronium administration. This case indicates the possible involvement of elevated sympathetic nervous system to a catecholamine crisis triggered by rocuronium in pheochromocytoma.
Adrenal Medulla ; Androstanols ; Anesthesia, General ; Anesthetics ; Arterial Pressure ; Atracurium ; Catecholamines ; Humans ; Norepinephrine ; Pancuronium ; Pheochromocytoma ; Plasma ; Sympathetic Nervous System

The Griffith and Johnson's report of the successful use of curare in 1942 brought a revolution in anesthetic care. The only depolarizing agent still in use is succinylcholine due to its rapid onset of action and rapid recovery. However, its use is limited by serious side effects (hyperkalemia, malignant hyperthermia, arrhythmia, etc). New non-depolarizing neuromuscular blocking agents have been studied to replace succinylcholine, which are still at a preclinical level. Rocuronium is an aminosteroid compound and has an intermediate duration of action, but the onset is shorter. A new method of reversing neuromuscular blockade has been advocated by the introduction of a cyclodextrin, sugammadex (Org 25969), which is still at the investigational stage in humans. It has a high affinity for rocuronium, with which it forms a complex. Sugammadex has a lower affinity for other steroidal neuromuscular blocking agents such as vecuronium and pancuronium, and does not bind benzylisoquinoline-type neuromuscular blocking agents. The ability to produce a rapid return of twitch height even at deep levels of paralysis and the lack of side effects make this compound a promising new agent for anesthesia.
Anesthesia ; Arrhythmias, Cardiac ; Curare ; Humans ; Malignant Hyperthermia ; Neuromuscular Blockade* ; Neuromuscular Blocking Agents ; Pancuronium ; Paralysis ; Succinylcholine ; Vecuronium Bromide

The study was conducted at 3 provinces: Bac Ninh, Nam Dinh and Ha Tay from November 2001 to July 2002. At each province, 100 women, aged from 21 to 39years old, average blood pressure of 107/68mmHg, average weight of 47kg and average height of 154cm were selected into study. Study on acceptability of 300 Vietnamese women using contractive drug Mercilon, the results showed that: satisfying and acceptance rate is so high about 99%, the side effect was just a little and decreased gradually depending on using duration, menstrual periods are in monthly and frequently, only 1 case faced with amenorrhea, and another case experienced excessive menstruation, 4 cases give up study because of side effects. Thus, satisfying and acceptance rate in Vietnamese women is so high.
Contraceptive Agents ; Women ; Pancuronium

BACKGROUND: The alpha2-agonist clonidine is an adjunct in general anesthesia. Clonidine constricts cerebral arteries and decreases cerebral blood flow (CBF), but does not alter cerebral metabolic rate (CMR). Thus cerebral ischemia is possible due to CBF/CMR imbalance. This study was designed to prove the effects of clonidine bolus up on CBF and CO2 reactivity in desflurane anesthesia. METHODS: Thirty patients were divided into a clonidine group (n = 15) and a control group (n = 15). Anesthesia was induced with thiopental and pancuronium, and maintained with 50% N2O/O2/ Desflurane. The jugular bulb was cannulated to measure jugular bulb oxygen saturation (SjO2). MAP and SjO2 were measured after induction, after clonidine (2 microgram/kg) or normal saline administration and during hyperventilation. RESULTS: After clonidine administration, MAP decreased from 95.7+/-9.8 mmHg to 81.1+/-6.3 mmHg and was 79.9+/-5.0 mmHg during hyperventilation. In the control group, the corresponding MAP values 95.7+/-9.8 mmHg, 81.1+/-6.3 mmHg and 79.9+/-5.0 mmHg. After clonidine administration, SjO2 was decreased from 84.7+/-3.7% to 81.1+/-5.2%, and was 71.5+/-8.4% during hyperventilation (P = 0.003, P = 0.000) and in control group, there were 95.7+/-9.8%, 81.1+/-6.3% and 79.9+/-5.0%, respectively. CO2 reactivity was expressed as a change of SjO2 per unit change of PaCO2, 1.15+/-1.19%/mmHg versus 1.43+/-0.98%/mmHg (P = 0.49). CONCLUSIONS: During desflurane anesthesia, clonidine-induced constriction of the cerebral arteries was demonstrated but CO2 reactivity was well preserved.
Anesthesia* ; Anesthesia, General ; Brain Ischemia ; Carbon Dioxide* ; Carbon* ; Cerebral Arteries ; Clonidine* ; Constriction ; Humans ; Hyperventilation ; Oxygen* ; Pancuronium ; Thiopental

BACKGROUND: This study was designed to evaluate the hemodynamic effects of vecuronium, pancuronium and rocuronium in patients with coronary artery disease (CABG) or valvular heart disease (VHD). METHODS: With IRB approval, 121 patients (61 patients with CABG and 60 patients with VHD) were randomly divided into a vecuronium, pancuronium and rocuronium group, respectively. Midazolam and fentanyl were administered and then 3 times of ED95 of a muscle relaxant (vecuronium, 0.12 mg/kg; pancuronium, 0.12 mg/kg; or rocuronium, 0.9 mg/kg) was injected. Additional dose of fentanyl was given and the patient was intubated. Hemodynamic variables were measured before the induction of anesthesia, just prior and 1 min after the administration of the muscle relaxant, just before intubation, 5 and 10 min after intubation. RESULTS: The number of patients enrolled in the CABG-vecuronium, CABG-pancuronium, CABG- rocuronium, VHD-vecuronium, VHD-pancuronium, and VHD-rocuronium was 20, 20, 21, 19, 20, and 21 respectively. Each of 10, 4, 4, 5, 1, and 1, respectively, were treated for hypotension or bradycardia during the induction of anesthesia. The heart rate (HR) changed significantly only in the CABG- vecuronium group compared with the control value. All three muscle relaxants decreased mean systemic artery pressure (MAP) significantly in both CABG and VHD patients. The decrease in HR and MAP were significantly greater in CABG-vecuronium and VHD-vecuronium than in CABG-pancuronium and VHD-pancuronium, respectively. The decrease in HR was also greater in VHD-vecuronium than in VHD-rocuronium. Cardiac index (CI) decreased in CABG-vecuronium and all VHD patients. The decrease in CI was greater in CABG-vecuronium than in CABG-pancuronium but it was not significantly different among the three muscle relaxants in VHD patients. CONCLUSIONS: While pancuronium and rocuronium exerted minimal hemodynamic effects, vecuronium reduced HR and MAP more significantly than pancuronium in both CABG and VHD patients, and CI also decreased more significantly with vecuronium in CABG patients.
Anesthesia* ; Arteries ; Bradycardia ; Coronary Artery Disease* ; Coronary Vessels* ; Ethics Committees, Research ; Fentanyl ; Heart Rate ; Heart Valve Diseases* ; Hemodynamics* ; Humans ; Hypotension ; Intubation ; Midazolam ; Pancuronium* ; Vecuronium Bromide*

Malignant hyperthemia is an autosomal-dominant inherited disorder of the skeletal muscle cell charac terized by a hypermetabolic response to all commonly used inhalational anesthetics and depolarizing muscle relaxants. The clinical syndrome includes muscle rigidity, hypercapnia, tachycardia and myoglobinuria as result of increased carbon dioxide production, oxygen consumption and muscle membrane breakdown. Early recognition and vigorous treatment are very important factors to determine patient's prognosis in malignant hyperthermia. However, it is very difficult to diagnose malignant hyperthermia during anesthesia because malignant hyperthermia presents with multiple nonspecific signs and laboratory findings of variable intensity and time course during and after exposure to anesthetic agents. We report a case of malignant hyperthermia which was diagnosed early using capnography before the appearance of hyperthermia and successfully treated. The malignant hyperthermia episode developed 20 minutes after induction of anesthesia with thiopental sodium, pancuronium, isoflurane, N2O and O2. When we suspected episode, we could not observe any classical signs of malignant hyperthermia except unexplained tachycardia and elevated end-tidal CO2. We discuss here the usefulness of capnography in early recognition of malignant hyperthermia and the importance of early recognition in prognosis.
Anesthesia ; Anesthetics ; Capnography* ; Carbon Dioxide ; Fever ; Hypercapnia ; Isoflurane ; Malignant Hyperthermia* ; Membranes ; Muscle Rigidity ; Muscle, Skeletal ; Myoglobinuria ; Neuromuscular Depolarizing Agents ; Oxygen Consumption ; Pancuronium ; Prognosis ; Tachycardia ; Thiopental

BACKGROUND: The use of a low-dose naloxone infusion concomitant with intravenous morphine PCA (patient-controlled analgesia) attenuates opioid-related side effects without reducing analgesic effects. The authors compared the incidence of morphine-related side effects and the quality of analgesia in adding low-dose naloxone, normal saline or droperidol to an IV fentanyl PCA regimen. METHODS: One hundred eight patients undergoing ocular plastic surgery were enrolled in the study. General anesthesia was induced and maintained with propofol TCI (target controlled infusion), vecuronium or pancuronium and nitrous oxide. After intubated, they received intravenous fentanyl as PCA. They were randomized to receive normal saline, droperidol or low-dose naloxone concomitant with IV fentanyl PCA. Verbal rating scores for pain, the degree of patients' satisfaction (1-4), nausea, vomiting, requests for antiemetics, urinary retention, pruritus and respiratory depression were recorded after 24 hours. RESULTS: There was no difference in the VRS (verbal rating score) for pain, degree of the satisfaction and the incidence of nausea, vomiting and requests of antiemetics among the three groups. There was no incidence of pruritus or respiratory depression. One subject developed urinary retention in the control group, and three cases in the droperidol group, but none was developed in the low-dose naloxone group. CONCLUSIONS: There was no difference in the prevention of postoperative nausea, or vomiting among the normal saline, droperidol, and naloxone groups with an IV fentanyl PCA. Low-dose naloxone, however, had a reducing effect on urinary retention; it may become an alternative choice according to the anesthesiologist's preference.
Analgesia ; Analgesia, Patient-Controlled* ; Anesthesia, General ; Antiemetics ; Droperidol ; Fentanyl* ; Humans ; Incidence ; Morphine ; Naloxone* ; Nausea ; Nitrous Oxide ; Pancuronium ; Passive Cutaneous Anaphylaxis ; Postoperative Nausea and Vomiting ; Propofol ; Pruritus ; Respiratory Insufficiency ; Surgery, Plastic ; Urinary Retention ; Vecuronium Bromide ; Vomiting

BACKGROUND: The cardiovascular dysfunction frequently accompanies sleep apnea syndrome, but the exact pathophysiology of cardiovascular dysfunction still remains uncertain. Moreover, most studies are concerned with obstructive sleep apnea syndrome and the studies of central sleep apnea syndrome are rare. METHODS: We studied with sixteen dogs which were anesthetized with intravenous pancuronium bromide. We created nonobstructive breath hold (apnea) in anesthetized dogs by means of alternating fixed duration (30s) of apnea and mechanical ventilation (breathing). After five or seven repetitions of this apnea-breathing cycle, we measured arterial oxygen pressure, arterial carbon dioxide pressure, heart rate, cardiac output, mean femoral artery pressure and mean pulmonary artery pressure separately before apnea (baseline), 25s after apnea (apneic period), 10s (early phase of postapneic period) and 25s (late phase of postapneic period) after resumption of breathing. We analysed the impact of oxygen trial on the hemodynamic changes by comparing measures of the eight 30% oxygen breathing dogs with the other eight room air breathing dogs. RESULTS: Heart rate decreased significantly at apneic period compared to baseline (p<0.05), and increased significantly at early and late phase of postapneic period compared to apneic period (p<0.05). After oxygen trial, this change of heart rate showed significant difference (p<0.05). Cardiac output only tended to decrease during late phase of postapneic period by comparison with baseline and apneic period. Mean femoral artery pressure of apneic period increased more than that of baseline (p<0.05), and persisted until late phase of postapneic period (p<0.05). When oxygen was supplied, this change of increase disappeared, but did not show statistical significance. Mean pulmonary artery pressure did not change according to apnea-breathing cycle and oxygen trial. CONCLUSION: In anesthetized dogs with periodic nonobstructive apnea, the changes of heart rate, cardiac output, mean femoral artery pressure were noted and the change of heart rate was closely related with hypoxia. Through this study, indirectly, we were able to understand partially the changes of cardiovascular function in patients with central sleep apnea syndrome.
Animals ; Anoxia ; Apnea* ; Arterial Pressure ; Carbon Dioxide ; Cardiac Output ; Dogs* ; Femoral Artery ; Heart Rate ; Hemodynamics* ; Humans ; Oxygen ; Pancuronium ; Pulmonary Artery ; Respiration ; Respiration, Artificial ; Sleep Apnea Syndromes ; Sleep Apnea, Central ; Sleep Apnea, Obstructive

BACKGROUND: The purpose of this study was to evaluate mivacurium in the pharmacokinetics of onset and offset. METHODS: In 127 adult patients of ASA physical status I or II without any factors involving the neuromuscular function under general anesthesia, onset time (lag and manifest time) and clinical duration were measured after bolus or divided doses of ED95 x 2 of succinylcholine (SCC), rocuronium (ROC), atracurium (ATR), mivacurium (MIV), pancuronium (PAN) or vecuronium (VEC). Recovery time was defined as the recovery index and total duration measured after subsequent ED95 of MIV at 25% recovery of control twitch height from neuromuscular block induced by ED95 x 2 of ATR, MIV, PAN or VEC. Plasma cholinesterase (PChE) levels were measured following PAN or ATR. RESULTS: Onset time was faster with SCC and ROC, the low potency drugs, than with ATR, MIV, PAN or VEC, the high potent drugs. Manifest time was shorter in low potency drugs but longer in high potency drugs than lag time after bolus or divided doses of muscle relaxants given. Divided doses of various drugs induced a shortened onset time, but the patterns of relationship between lag and manifest time associated with drug potency did not alter. The recovery times with administered MIV were slowest after PAN pretreatment, and fastest after MIV pretreatment. PChE levels decreased significantly from 3 min to over 180 min after PAN administeration but not ATR. CONCLUSIONS: The onset time of MIV was not improved due to high drug potency as other nondepolarizing neuromuscular blockers. However, in spite of high potency, the recovery time of MIV was faster than other drugs. This results may be depend upon PChE activity rather than drug potency. Additionally, the prolonged recovery of MIV was not only under the influence of low PChE activity but also other some factors such as: the first relaxants administered before MIV dominated the neuromuscular block so that the duration of MIV given subsequently changed to resemble that of the first. The longer elimination half-life of the underlying relaxant prolonged the effects of subsequentshorter acting MIV. Structural similarities or dis-similarities between the interacting MIV and other drugs may have effects more potent in dis-similarity than in similarity.
Adult ; Anesthesia, General ; Atracurium ; Cholinesterases ; Half-Life ; Humans ; Neuromuscular Blockade ; Neuromuscular Blocking Agents ; Pancuronium ; Pharmacokinetics* ; Plasma ; Succinylcholine ; Vecuronium Bromide