BACKGROUND: The timing of administration may be an important factor in order to obtain maximal antagonizing effect of anticholinesterase on neuromuscular blockade. The objective of this study is to seek for the optimal administration time of pyridostigmine for reducing the recovery time of vecuronium. METHODS:Thirty patients were devided into three groups,who were receiving intravenously pyridostigmine (0.2 mg/kg) at 10% (group 1), 20% (group 2) and 25% (group 3) recovery of T1. The recovery indices (RI: time taken for T1 to recover from 25 to 75% of control) and recovery time (time taken for T1 to recover from 5% to 20, 25, 50 & 75%) in vecuronium (0.1 mg/kg) neuromuscular blockade were checked and compared between 3 groups using train of four stimulation with Relaxograph(Datex co., Finland). RESULTS: The recovery time (T5-20, T5-25, T5-50, T5-75) was significantly faster in the group 1 than the group 3. But there were no significant differences in recovery indices (RI) between 3 groups. CONCLUSIONS: Provided there is a slightest evidence of spontaneous recovery, early administration of anticholinesterse will reduce the recovery time of nondepolarizing neuromuscular block. But it can not affect the dissociation rate of vecuronium (KD) and there were no significant differences in recovery indices.
Humans ; Neuromuscular Blockade* ; Pyridostigmine Bromide* ; Vecuronium Bromide

BACKGROUND: Postoperative residual curarization subsequent to the use of neuromuscular blocking drugs can cause respiratory problems. This study examined the incidence of postoperative residual curarization on the arrival of patients in the recovery room. METHODS: Two-hundred-fifty-nine patients were enrolled in the study. The neuromuscular blockade was maintained with vecuronium or rocuronium and all subjects were reversed with pyridostigmine. The train of four ratios (TR) was quantified by acceleromyography immediately upon their arrival in the recovery room. The residual curarization was defined as a TR of < 0.9. RESULTS: The incidence of residual curarization was 32.8% (84 patients). The time from the last dose of muscle relaxants to the TR assessment in the recovery room was significantly different between those with a TR <0.9 (74.9 +/- 35.3 min) and a TR > 0.9 (104.5 +/- 51.1 min) patients. The total dose of muscle relaxants corrected by the ED95 was significantly different between TR < 0.9 and TR > or = 0.9 patients. The total dose of vecuronium or rocuronium, and the dose of pyridostimine was similar in the TR < 0.9 and TR > or = 0.9 patients. CONCLUSIONS: Significant postoperative residual curarization waspresent in the majority of patients, even with the use of intermediate- acting neuromuscular blocking drugs. In addition, the time from the last dose of muscle relaxants to the TR assessment in the recovery room is a major factor that affects the residual curarization.
Humans ; Incidence ; Neuromuscular Blockade ; Pyridostigmine Bromide ; Recovery Room* ; Vecuronium Bromide*

The success of accelerating the onset of neuromvacular blocking drugs by giving them in divided doses encouraged others to attempt the same "priming principle" using reversal agents. Naguib et al and Abdulatif et al demonstrated that the reversal time(time to reach a TOF of 0.75) was reduced when the reversal agent was administered in divided doses at T, 10% of control. But Donati et al and Szalados et al either could not detect any differences in the rate of reversal when anticholinestereses were administered in divided doses. This study hes been conducted to evaluate the reversal effects of neostigmine or pyridostigmine with priming principle in the rabbit after pancuronium injection when pro- found relaxation(PTC=0) was confirmed. Rabbits(n=60) were randomly allocated to 4 groups. After pancuranium 0.2mg/kg IV, the onset and recovery times were evalusted. When the profound relaxation(PTC=0) was confirmed at Smin. after pancuronium injection, neostigmine 50 ug/kg and atropine sulfate (atropine) 20 ug/kg were injected in group 1. At thst time, neostigmine 10/kg and atropine 4 ug/kg were injected and after 3min. neostigmine 40/kg and atropine 16 ug/kg were injected in group 2. At that time, pyridostigmine 250 ug/kg and atropine 20 ug/kg were injected in group 3. At that time, pyridostigmine 50 ug/kg and atropine 4 ug/kg were injected and after 3min. pyridostigmine 200 ug/kg and atropine 16 ug/kg were injected in group 4. The results were as follows :. 1) The time until 75% recovery of twitch amplitude was 53.1+/-12.4min. in group 1, 44.9+/-212.1min. in group 2, 54.9+/-9.7min. in group 3 and 48.2+/-7.1min. in group 4. The reversal times were tended to reduce when the reversal agents were administered with "priming principle" at the profound relaxation. 2) At the profound relaxation the reversal effects of neostigmine were greater than that of pyridostigmine.
Atropine ; Cholinesterase Inhibitors* ; Muscle Relaxation* ; Neostigmine ; Pancuronium ; Pyridostigmine Bromide ; Relaxation

Obesity is associated with an impairment of the growth hormone secretion elicited by all stimuli known to date, but the basic mechanism of the alteration is unknown to date, but the basic mechanism of this alteration is unknown. To determine whether obesity is associated with a chronic state of tonic somatostatin secretion, several tests with growth hormone stimuli such as GHRH(1 microgram/kg), clonidine(150 microgram/m(2))and Regular insulin (0.1U/kg, subcutaneously), to obese subjects and normal control with or without pyridostigmine were undertaken, and the Somatomedin-c levels were measured in both obese subjects and matched controls. 1) The peak GH levels and AUC-GH after administration of GHRH, Clonidine or Regular insulin in obese group is less than those in control group. 2) Pretreatment with pyridostigmine increased the peak GH levels and AUC-GH significantly in obese group but the absolute values are less than those of normal group. 3) The Somatomedin-c levels are significantly higher in obese group than control. Our results lend support to the view that chronically high level of somatostatin decreases the responsiveness to GHRH and secretion itself.
Child* ; Clonidine ; Growth Hormone* ; Humans ; Insulin ; Obesity* ; Pyridostigmine Bromide ; Somatostatin

Ophthalmoplegia following snake bite is a rare but not serious neurotoxic complication. However, symptoms like diplopia, blurred vision, and ocular discomfort can be emotionally devastating for a patient. We experienced one case f ophthalmoplegia following a snake bite. The patient complained of diplopia and ptosis that had developed several hours after the snake bite. The symptoms were completely resolved after pyridostigmine medication with antivenin treatment.
Cholinesterase Inhibitors ; Diplopia ; Humans ; Ophthalmoplegia* ; Pyridostigmine Bromide ; Snake Bites* ; Snakes*

No abstract available.
Female ; Growth Hormone* ; Humans ; Levodopa* ; Polycystic Ovary Syndrome* ; Pyridostigmine Bromide*

BACKGROUND: Although the incidence of postoperative residual curarization (PORC) following the use of intermediate-acting neuromuscular blocking agents is lower than that of longer-acting neuromuscular blocking agents, it has been reported in many studies. We compared the incidence of PORC following either rocuronium or vecuronium given by intermittent bolus or continuous infusion dosing. METHODS: Ninety-eight patients were included in this study. Neuromuscular blocking drugs were administered based solely on clinical criteria, and the reversal agent pyridostigmine was given to all patients. Residual block following rocuronium infusion (Group R-I), rocuronium bolus (Group R-B), vecuronium infusion (Group V-I), or vecuronium bolus dosing (Group V-B) was evaluated on arrival in the postanesthesia care unit. Neuromuscular function was assessed acceleromyographically (using TOF-Watch(R) to measure the train-of-four (TOF) ratio) and also clinically. PORC was defined as a TOF ratio of < 0.8. RESULTS: The incidence of PORC on arrival in the postanesthesia care unit was 20% in Group R-I, 23% in Group R-B, 42% in Group V-I, and 19% in Group V-B. Mean TOF ratio in Group V-I was less than those of the other groups (P < 0.05). CONCLUSIONS: PORC is still common following vecuronium or rocuronium, even after the block is antagonized, if neuromuscular blocking agents are administered according to clinical criteria alone.
Anesthesia Recovery Period ; Humans ; Incidence ; Neuromuscular Blockade ; Neuromuscular Blocking Agents ; Pyridostigmine Bromide ; Vecuronium Bromide*

Time to antagonism induced by pyridostigmine from different levels of neuromuscular blockade was evaluated in 45 patients anesthetized with nitrous oxide, fentanyl, and vecuronium. Neuromuscular blockade, as monitered by train-of-four count, was antagonized at varing degrees of spontaneous recovery. Train-of-four ratio was used as an index of the ability of the patients to maintain adequate spontaneous ventil'ation, and maximum inspiratory pressure as an index of the ability of the patients to protect their airways against aspiration or obstruction. We measured time from administration of pyridostigmine to train-of-four ratio of 70% indicating the recovery of the ability to maintain adquate spontaneous ventilation, and time to maximum inspiratory pressure of -45 cmH2O indicating the recovery of the ability to protect the patients airways against aspiration or obstruction. For a train-of-four count level of 0-1, reversal time to train-of-four ratio of 70% was 22.73+/-3.00 minutes and that to maximum inspiratory pressure of -45 cmH2O was 30.33+/-2.69 minutes. For a train-of-four count level of 2- 3, reversal time to train-of-four ratio of 70% was 17.33+/-3.18 minutes and that to maximum inspiratory pressure of -45cmH2O was 22.27+/-2.91 minutes. For a train-of-four count level of 4, reversal time to train-of-four ratio of 70% was 8.40+/-3.58 minutes and that to maximum inspiratory pressure of -45 cmH2O was 14.60+/-3.11 minutes. It is concluded that the more shallow is the neuromuscular blockade, the more rapid and the safer is the reversal of neuromuscular blockade, although the dose of reversal drug was determined according to the depth of neuromuscular blockade. Moreover, it should take more than 30 minutes to antagonixe profaund neuromuacular hlock- ade induced by vecuronium to such a degree that not only can the patients maintain adequate spontaneous ventilation, but they can maintain the airways and protect them against aspiration as well.
Fentanyl ; Humans ; Neuromuscular Blockade* ; Nitrous Oxide ; Pyridostigmine Bromide ; Vecuronium Bromide* ; Ventilation

Despite the fact that the anticholinesterases, mainly neostigmine, has been used for many years to antagonize a nondepolarizing neuromuscular blockade, until recently nothing was known about their pharmacokinetics and dynamics in anesthetized patients. This deficiency was largely due to lack of a suitable analytic technique to measure the concentration of these drugs in body fluids, most importantly serum. Recently it was developed a method by which the serum concentrations of neostigmine, pyridostigmine, edrophonium and their metabolities can be measured. Recently,k pyridostigmine and edrophonium have gained popularity to use for reversing a nondepolarizing muscle relaxants. We have studied newly introduced vecuronium effects and its reversal with pyridostigmine. The results were as follows: 1) Spontaneous recovery index by vecuronium 0.1mg/kg was 620.8 sec. 2) Recovery index by the pyridostigmine 160ug/kg reversal was significantly shortened as 134.0sec in vecuronium 0.1mg/kg block. 3) Tetanic stimulation (100Hz, 5sec) was sustained after 75% recovery of twitch height by pyridostigmine 160ug/kg reversal.
Body Fluids ; Cholinesterase Inhibitors ; Edrophonium ; Humans ; Neostigmine ; Neuromuscular Blockade* ; Pharmacokinetics ; Pyridostigmine Bromide* ; Rabbits* ; Vecuronium Bromide*

Anesthesiologists may have close relationship with muscle relaxants in clinical practice. Fourtunately, a few of the new muscle relaxants were discovered and used in clinic recently. Newly introduced non-depolarizing muscle relaxant: vecuronium has been clinically in use recently. The most suitable method for reversing the neurom uscular blockade caused by vecuronium continues to provoke discussion and differences of opinion. Simultaneous administration of neostigmine and atropine has been considered safe by some authors and dangerous by others. Both slow and rapid administration have been recommended. The general acceptance of the slow administration of neostigmine and atropine has been confirmed. In view of the various data on vecuronium reversal, neostigmine was compared with pyridostigmine and heart rate changes were studied. The results were as follows: 1) Recovery index after i.v. neostigmine 40 ug/kg and atropine 20 ug/kg when first twitch of the "train of four" was appeared during vecuronium 0.1mg/kg relaxation, was 129.9 sec. Heart rate change was decreased to 46.9/min(15%) after i.v. neostigmine during 16 to 20 minutes period(p<0.05). 2) Recovery index after i.v. pyridostigmine 160 ug/kg and atropine 20ug/kg when first twitch of the "train of four" was appeared during vecuronium 0.1mg/kg relaxation, was 134.0sec. Heart rate change was not statistically significant compared with neostigmine.
Atropine ; Heart Rate ; Neostigmine* ; Neuromuscular Blockade ; Pyridostigmine Bromide* ; Rabbits* ; Relaxation ; Vecuronium Bromide*