AIMTo establish a method to determine the isotope ratios of 13C to 12C of dehydroepiandrosterone and its metabolites in urine, for detecting the source of dehydroepiandrosterone or its metabolites.

METHODSPreliminary separation of endogenous anabolic androgenic steroids could be achieved using solid phase extraction, enzymolysis and thin layer chromatography. The source of dehydroepiandrosterone and other endogenous anabolic androgenic steroids could be detected by their delta values with gas chromat ography-combustion-isotope ratio mass spectrometry.

RESULTSThe 5 values of some metabolites of dehydroepiandrosterone reduced after the administration of dehydroepiandrosterone preparation. In these cases the data indicated that exogenous anabolic androgenic steroids were administrated.

CONCLUSIONThe source of dehydroepiandrosterone or its metabolites in urine could be detected by measuring their delta values with this method.

Adult ; Androstane-3,17-diol ; urine ; Androsterone ; urine ; Chromatography, Thin Layer ; methods ; Dehydroepiandrosterone ; metabolism ; Doping in Sports ; Etiocholanolone ; urine ; Female ; Gas Chromatography-Mass Spectrometry ; methods ; Humans ; Male ; Pregnanetriol ; urine ; Substance Abuse Detection ; methods

BACKGROUND: During ophthalmologic surgery, various intravenous anesthetic induction agents are used to prevent an intraocular pressure (IOP) increase. This study was designed to compare the effects of vecuronium and rocuronium on IOP in patients who were intubated. METHODS: Thirty-two patients undergoing elective strabismus surgery, aged 4 to 12 years, were randomized to receive rocuronium 0.6 mg/kg (Group 1, n = 16), or vecuronium 1.0 mg/kg (Group 2, n = 16).IOP, mean arterial pressure (MAP), and heart rate (HR) were measured at the following time points: prior to induction (B); after the administration of the induction agents; before intubation (T0); and at 1, 3 and 5 mins after intubation (T1, T3 and T5). RESULTS: The IOP after T0 in Group 1 was significantly lower than B (P < 0.05) in Group 2.The IOP at T1 in the Group 1 and 2 was not different from B, respectively.The IOP, MAP, and HR at T1 in the Groups 1 and 2 were significantly higher than at T0 (P < 0.05).No significant differences were observed between the groups in term of IOP. CONCLUSIONS: We concluded that vecuronium and rocuronium are both useful as muscle relaxants for use in general anesthesia in ophthalmologic surgery, because both agents caused similar decreases in intraocular pressure.
Aged ; Androstanols ; Anesthesia, General ; Arterial Pressure ; Heart Rate ; Humans ; Intraocular Pressure ; Intubation ; Muscles ; Strabismus ; Vecuronium Bromide

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

Vecuronium has been used for long surgical procedure by infusion or intermittent injection. However, such methods are not economical. It may be that the use of longer acting pancuronium followed by vecuronium would offer the advantages of economy and rapid recovery. The aim of this study was to investigate the duration of effect of vecuronium administered after pancuronium. Eighteen patient reguiring prolonged major surgery were given intravenous pancuronium 0.06 mg/ kg (ED95) after induction of anesthesia and a dose of pancuronium 0.06 mg/kg (Group I, nine patients) or vecuronium 0.01 mg/kg (Group II, nine patients) was given at the recovery of neuromuscular transmission where the response to the first stimulus (T1) was 25% of control response. As a result, the time of onset, recovery time of 25%, 50% and 75% of control response T1 and recovery index was to be shorter with vecuronium than with pancuronium. It is concluded that vecuronium administered at the end of surgery after pancuronium is effective for shorting the duration of recovery time.
Anesthesia ; Humans ; Pancuronium* ; Vecuronium Bromide*

No abstract available.
Androstanols ; Humans ; Kidney Failure, Chronic

BACKGROUND: Some studies have shown that rocuronium and vecuronium have additive, or synergistic effects on muscle relaxation based on the Loewe additivity. Therefore, we performed a fit of tetanic fade data to a generalized response surface model with varying relative potencies proposed by Kong and Lee (KLGRS) to evaluate the usefulness of KLGRS for capturing the interspersed drug interactions and to characterize the interaction between the two drugs. METHODS: Left phrenic nerve-hemidiaphragms (Male Sprague-Dawley rats, 150-250 g) were mounted in Krebs solution. Supramaximal electrical stimulation (0.2 ms, rectangular) of 50 Hz for 1.9 s to the phrenic nerve evoked tetanic contractions that were measured with a force transducer. Each preparation was exposed to one of 4 vecuronium concentrations (0.0, 1.5, 2.5, and 3.0 microM), or one of 4 rocuronium concentrations (0.0, 3.0, 4.5, and 5.5 microM). Subsequently the adequate amount of rocuronium was added to a vecuronium bath and that of vecuronium was added to a rocuronium until an 80-90% increase in tetanic fade was achieved. We then fitted the modified KLGRS models to the above data, after which we selected the best model, based on 5 methods for determining goodness of fit. Using this method, we obtained the response surface, as well as contour plots for the response surface (i.e. isoboles), the polynomial function and the interaction index. RESULTS: The model with the constant relative potency ratio and 8 parameters was found to best describe the results, and this model reflected well the characteristics of the raw data. In addition, the two drugs showed a synergistic interaction in almost every area and an antagonistic one in a very narrow area. CONCLUSIONS: KLGRS was found to be a useful method of analyzing data describing interspersed drug interactions. The interaction between rocuronium and vecuronium was found to be synergistic.
Androstanols ; Baths ; Contracts ; Drug Interactions ; Electric Stimulation ; Isotonic Solutions ; Muscle Relaxation ; Phrenic Nerve ; Rats, Sprague-Dawley ; Refractory Period, Electrophysiological ; Transducers ; Vecuronium Bromide

Rocuronium is the anesthetic agent most likely to cause anaphylaxis. Immediately after intravenous rocuronium administration, the authors experienced ventilatory impairment due to unilateral bronchospasm (left lung), which was relieved by emergency treatment. However, 80 minutes after beginning laparoscopic surgery for rectal cancer, the left lung suddenly re-collapsed under pneumoperitoneum in the Trendelenburg position. A postoperative intradermal test revealed that rocuronium, vecuronium, atracurium, succinylcholine, or thiopental could induce anaphylaxis in this patient, but it was not established whether the second incident during surgery was due to endobronchial intubation or anaphylactic bronchospasm. This case cautions that under pneumoperitoneum in the Trendelenburg position, patients suspected of being prone to anaphylactic bronchospasm should also be considered at risk of endobronchial intubation.
Anaphylaxis ; Androstanols ; Atracurium ; Bronchial Spasm ; Emergency Treatment ; Head-Down Tilt ; Humans ; Intradermal Tests ; Intubation ; Laparoscopy ; Lung ; Pneumoperitoneum ; Rectal Neoplasms ; Succinylcholine ; Thiopental ; Vecuronium Bromide ; Ventilation

OBJECTIVETo study the pharmacodynamics of vecuronium,atracurium, mivacurium and rocuronium in patients with end-stage renal failure.

METHODSForty-six patients with end-stage renal failure scheduled for renal transplantation and 53 patients with normal renal function were given either vecuronium, atracurium, mivacurium or rocuronium. The neuromuscular effects were monitored by the evoked response of the adductor pollicis to train-of-four stimulation of the ulnar nerve.

RESULTSOnset of vecuronium, atracurium and mivacurium occurred faster or tended to be faster in patients with end-stage renal failure, but there was no significant difference in onset by rocuronium between the control patients and renal failure patients. Furthermore, the no-response period, duration of action and recovery of atracurium did not differ between the two groups. There was no significant difference in duration of action or recovery of mivacurium between the two groups, whereas its no-response period was significantly prolonged in the patients with end-stage renal failure. There was no difference in no-response period or duration of action after the initial dose of vecuronium or rocuronium between the two groups. However, no-response period and duration of effect by vecuronium and rocuronium were prolonged with increasing incremental doses in patients with end-stage renal failure.

CONCLUSIONSAll four muscle relaxants could be safely used in patients with end-stage renal failure. Onset of the relaxants were, in some cases, accelerated and no-response period of mivacurium was prolonged in patients with end-stage renal failure undergoing dialysis therapy. End-stage renal failure prolonged the no-response period and duration of action of vecuronium and rocuronium after repeated incremental doses, but did not alter those attributed to atracurium.

Adult ; Androstanols ; pharmacology ; Anesthesia, General ; Atracurium ; pharmacology ; Female ; Humans ; Isoquinolines ; pharmacology ; Kidney Transplantation ; Male ; Middle Aged ; Neuromuscular Blocking Agents ; pharmacology ; Succinylcholine ; pharmacology ; Time Factors ; Vecuronium Bromide ; pharmacology

Rocuronium is a non-depolarizing neuromuscular blocking agent which has a rapid onset and intermediate duration of action. The goal of this study was to compare the neuromuscular blocking actions of rocuronium with and without a priming dose of pancuronium or rocuronium in children. Thirty patients were randomly allocated into 3 groups. Ten patients received a single dose of 0.6 mg/kg rocuronium (Group I). The others received either 0.015 mg/kg pancuronium (Group II) or 0.06 mg/kg rocuronium (Group III) 3 minutes before an intubating dose of 0.54 mg/kg rocuronium was given. Neuromuscular blockade was measured via accelerographic response to single stimulations (1 Hz) of the ulnar nerve until maximal twitch depression was reached followed by train-of-four (TOF) stimuli (2 Hz) at 15 second intervals for the remainder of recovery. Groups were compared with regard to onset time, duration and recovery indices. The onset time and duration of block did not differ significantly between groups. However, the time to recovery in group II (24.5 +/- 9.9 min) was significantly prolonged compared to that in group I (12.7 +/- 3.1 min) or group III (12.7 +/- 3.9 min). We concluded that the use of rocuronium with a preceding dose of either pancuronium or rocuronium provided no advantage for intubation in children.
Androstanols/therapeutic use* ; Child ; Comparative Study ; Drug Therapy, Combination ; Female ; Human ; Intubation, Intratracheal* ; Male ; Neuromuscular Nondepolarizing Agents/therapeutic use* ; Pancuronium/therapeutic use* ; Time Factors

BACKGROUND: The aim of this study was to evaluate whether slow injection of diluted rocuronium could reduce rocuronium-induced withdrawal movements effectively in children. METHODS: After loss of consciousness, rocuronium 0.6 mg/kg was administered into 171 children according to the pre-assigned groups as follows: Group CF, injection of non-diluted rocuronium over 5 seconds; Group CS, injection of non-diluted rocuronium over 1 minute; Group DF, injection of diluted rocuronium (10 times) over 5 seconds; Group DS, injection of diluted rocuronium over 1 minute. An investigator who was blind to the injection techniques recorded patient movements followed by rocuronium injection. RESULTS: The incidence of withdrawal movement in Group CF was highest among the groups (all P < 0.0001). Moreover, withdrawal movement was less frequently observed in Group DS than in Groups CS and DF (P = 0.021 and P = 0.007, respectively). CONCLUSIONS: Slow injection of diluted rocuronium reduced the incidence of withdrawal movements in children.
Androstanols ; Child ; Humans ; Incidence ; Research Personnel ; Unconsciousness