Repetitive nerve stimulation test(RNS) was performed on 32 patients with myasthenia gravis who showed positive response to the tensilon test. The result of the repetitive stimulation test before and after the tensilon injection was compared with the point of improvement of the CMAP and decremental response. The results were as follows: 1. All patients with myasthenis gravis showed decremental responses to the low rate of stimulation in RNS. 2. The results after tensilon injections showed significant improvements of the CMAP in ocularis oculi(OOC), flexor carpi ulnaris(FCU)(P <0.0005), deltoid and abductor digiti quinti muscles(ADQ)(P < 0.005). 3. There were improvements of decremental responses after tensilon injection. 1) At 2/sec, there were significant improvements in the muscles of ADQ(P <0.005), deltoidl OOC and FCU(P < 0.0005). 2) At 3/sec, there were significant improvements in the muscles of OOC(P <0.005), deltoid, FCU and ADQ(P < 0.0005). 3) At 5/sec, there were also significant improvements in all the muscles of OOC, deltoid, ADQ, FCU(P <0.0005). These results showed that tensilon improves the RNS abnorrnalities in myasthenic patients with positive tensilon test. We think these findings before and after the tensilon injection are helpful to diagnose and differentiate a patient with suspected myasthenia gravis who has a negative tensilon test or insignificant RNS findings.
Edrophonium* ; Humans ; Muscles ; Myasthenia Gravis*

Repetitive nerve stimulation test(RNS) was performed on 32 patients with myasthenia gravis who showed positive response to the tensilon test. The result of the repetitive stimulation test before and after the tensilon injection was compared with the point of improvement of the CMAP and decremental response. The results were as follows: 1. All patients with myasthenis gravis showed decremental responses to the low rate of stimulation in RNS. 2. The results after tensilon injections showed significant improvements of the CMAP in ocularis oculi(OOC), flexor carpi ulnaris(FCU)(P <0.0005), deltoid and abductor digiti quinti muscles(ADQ)(P < 0.005). 3. There were improvements of decremental responses after tensilon injection. 1) At 2/sec, there were significant improvements in the muscles of ADQ(P <0.005), deltoidl OOC and FCU(P < 0.0005). 2) At 3/sec, there were significant improvements in the muscles of OOC(P <0.005), deltoid, FCU and ADQ(P < 0.0005). 3) At 5/sec, there were also significant improvements in all the muscles of OOC, deltoid, ADQ, FCU(P <0.0005). These results showed that tensilon improves the RNS abnorrnalities in myasthenic patients with positive tensilon test. We think these findings before and after the tensilon injection are helpful to diagnose and differentiate a patient with suspected myasthenia gravis who has a negative tensilon test or insignificant RNS findings.
Edrophonium* ; Humans ; Muscles ; Myasthenia Gravis*

Sometimes it is not easy to make the diagnosis of myasthenia gravis (MG). The aim of our study was to understand the diagnostic sensitivities of tensilon, repetitive nerve stimulation (RNS), single fiber EMG (SFEMG) tests, acetylcholine receptor (AChR) antibodies (Ab), and to know their comparative significances for making diagnosis of MG. Those tests were safely completed in 40 myasthenia gravis, which consisted of 17 ocular, 21 generalized, 1 acute severe, 1 late severe MG. In all 40 subjects at least one of the tests was abnormal. The positive rates of tensilon, RNS tests, SFEMG, AChR Ab were 92.5%, 65.0%, 90.0%, and 82.5% respectively. The sensitivities of each tests were high in severe MG group, compared with those in mild MG group, because the positive rates were decreased from 100.0% to 89.2% in tensilon tests, from 83.3% to 57.1% in RNS test, from 100.0% to 89.2% in SFEMG tests and 91.7% to 78.6% in AChR Ab test. The positive results of RNS test was increased from 32.5% on abductor digiti quinti (ADQ) to 65.0% on orbicularis oculi (OOC). Among 3 cases with negative tensilon test, the RNS test in 1 case, the SFEMG tests were positive in all 3 cases, and the AChR Ab assay 1case. Among 3 cases with negative SFEMG, the tensilon tests were positive in 3 all cases, the RNS test in 1case and the AChR Ab assay in 1 cases. Among 5 cases, with negative RNS teses and negative AChR Ab assay, the tensilon tesrs wre positive in 3 cases and the SFEMG tests in 3 cases. Therefore we conclude that tensilon and SFEMG tests were more sensitive than RNS tests and AChR Ab assay. SFEMG test would be indicated to diagnose MG, especially in those mild MG cases with negative stensilon test. Also AChR Ab assay could improve diagnostic yields.
Acetylcholine ; Antibodies ; Diagnosis ; Edrophonium ; Myasthenia Gravis*

PURPOSE: This study was undertaken to evaluate the clinical usefulness of Tensilon test, repetitive nerve stimulation test(RNST), single fiber EMG(SFEMG) test and acetylcholine receptor antibody(AchR Ab) assay for making diagnosis of myasthenia gravis(MG). METHOD: These tests were performed in 21 MG patients which were classified into 11 ocular, 5 mild generalized, 4 moderate generalized, and 1 chronic severe MG. RESULT: The overall positivity of Tensilon test, SFEMG and AchR Ab was 95%, 87%, and 76% respectively. The overall positivity of RNST was 67%; 38% on flexor carpi ulnaris, 43% on adductor digiti quinti and 62% on orbicularis oculi muscles. The positivity of each test was higher in generalized MG group than in ocular MG group. But we could observe the statistically significant difference only in the RNST(p<0.05). CONCLUSION: Tensilon test showed the highest positivity in all MG groups. So we would like to recommend the Tensilon test for the diagnosis of MG at first, followed by RNST and AchR Ab assay, and SFEMG would be indicated to MG group which showed relatively low postivity in other tests.
Acetylcholine ; Diagnosis* ; Edrophonium ; Humans ; Muscles ; Myasthenia Gravis*

There are many reports which show that contraction of the extraocular muscles results in an increase in intraocular pressure(IOP). Goldmann tonometer was used to record IOP after Tensilon injection in 22 patients, 10 myasthenics and 12 patients with other neurologic disease. There was a significant difference in IOP measured at 30 seconds after injection between two groups; 1-7(mean: 3.4) mmHg increase in myasthenics but no change, or 1-6 (mean: 1.7) mmHg decrease in patients with other neurologic disease. It is concluded that Tensilon tonometry is a valuable, sensitive and objective method in the diagnosis of myasthenia gravis.
Diagnosis* ; Edrophonium* ; Humans ; Manometry* ; Muscles ; Myasthenia Gravis*

Authors had perforrned repetitive nerve stimulation tests on orbicularis oculi, flexor carpi ulnaris, and abductor digiti quinti muscles in 21 myasthenic patients and 40 normal controls using conventional Oh's rnethod and analysed statistically in detail. The results were as follows: 1) There were no significant statistical differences in CMAP and postexercise potentiation between normal controls and myastheic patients, but there were statistically significant decremental responses in both low-and high-rate of stimulation in myasthenic patients, with characteristic posttetanic potentiation and posttetanic exhaustion. 2) There were no statistical differences among Desmedt's, Stalberg's, and Oh's methods in determining the decremental ratio in low-rate of stimulation. 3) The proximal muscles showed more prominent decremental responses than distal muscles in myasthenic patients, and in three myasthenic patients, (14.3%) there were no statistically significant decremental responses in all tested muscles in spite of postivie edrophonium responses. 4) The gerleralized type myasthenic patients showed more prominent decremental responses than oclular type myasthenic patients. 5) Among the myasthenic patients, the oclular type myasthenic patients showed no statistically significant decremental response in both low-and high-rate of stimulation performed on flexor carpi ulnaris and abductor digiti quinti muscles.
Case-Control Studies* ; Edrophonium ; Humans ; Muscles ; Myasthenia Gravis*

Until recently edrophonium has not been used in clinical anesthesis because of its short duration of action and poor anticholinesterase activity. However there has been a renewed interest in the use of edrophonium for the reversal of the new intermediate acting relaxants, vecuronium and atracurium, which have a fast spontaneous recovery rate. Edrophonim in sufficient dosages may produce a fast onset of antagonism of non-depolarizing neuromuscular blockade with minimal muscarinic side effects. The porpose of this study was therefore to compare the efficiency of edrophonium and neostigmine in reversal of a profound neuromuscular blockad following continuous infusion of vecuronium (0.06 mg/kg/hr). Recovery of T1 and T4 twitch height, change of heart rate and mean arterial pressure were obsered after antagonism with control mixture group (n=10): neostigmine 0.04mg/kg and atropin 0.02 mg/kg, and experimental mixture group (n=9): edrophoninm 0.5mg/kg and atropine 0.007 mg/kg were evaluated respectively at the 10% spontaneous recovery of T1 twitch height. Recovery of T1 was more faster in the edrophonium group than in the neostigmine group but it was significant until 5 minutes after antagonism (p<0.05) and recovery of T4 was also significantly faster in the edrophonium group until 5 minutes after antagonism but thereafter, conversly faster in the neostigmine group than in the edrophonium(p<0.05). Changes of heart rate with +/-5% after edrophonium administration were observed. We conclude that edrophonium provides a more rapid antagonism within 5 minutes after antagonizing vecuronium infusion, and small change in heart rate, but no other any advantage in using edrophomine instead of neostigmine for reversal after 5 minutes.
Arterial Pressure ; Atracurium ; Atropine ; Edrophonium* ; Heart Rate ; Neostigmine* ; Neuromuscular Blockade ; Vecuronium Bromide*

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*

BACKGROUND: Spinal anticholinesterase has been shown to have an antinociceptive action to acute noxious stimuli. The purpose of this study was to determine the effect of intrathecal anticholinesterase on the facilitated state developed after tissue injury evoked by formalin injection. METHODS: Rats were implanted with lumbar intrathecal catheters. For nociceptive test, 50 microliter of 5% formalin solution was injected into the hindpaw. The effect of pretreatment with intrathecal neostigmine, physostigmine and edrophonium, administered 10 min before formalin injection, was observed for 60 min. For the evaluation of the effect of posttreatment with intrathecal anticholinesterase, administered 9 min after formalin injection, the response was observed for 50 min. RESULTS: Formalin injection into the paw resulted in a biphasic incidence of flinching of the injected paw. Intrathecal pretreatment with neostigmine, physostigmine and edrophonium produced a dose- dependent suppression of the flinching during phase 1 and phase 2 on the formalin test. Posttreatment with three intrathecal anticholinesterases reduced the phase 2 flinching response. CONCLUSIONS: Both pretreatment and posttreatment with intrathecal anticholinesterase produced an antinociception on the formalin test. These results point out the usefulness of anticholinesterase to acute nociception and facilitated state.
Animals ; Catheters ; Cholinesterase Inhibitors ; Edrophonium ; Formaldehyde* ; Incidence ; Neostigmine ; Nociception ; Pain Measurement* ; Physostigmine ; Rats*

BACKGROUND: The aim of this study was to evaluate the effect of 4-aminopyridine (4-AP) combined with anticholiesterase (antiChE) in antagonizing MgSO4-rocuronium-induced neuromuscualr blockade using a rat hemidiaphragm. METHODS: A hemidiaphragm with phrenic nerve was dissected and was mounted in a bath containing oxygenated Krebs solution. The phrenic nerve was stimulated supramaximally and the twitch response (0.1 Hz) was stabilized for at least 30 minutes. After maximal twitch inhibition by IC95 (concentration of 95% twitch inhibition) of rocuronium and MgSO4 20 mg was achieved, antagonistic effects of 1.6, 16 microgram/ml of edrophonium, 0.1, 1.0 microgram/ml of neostigmine, 0.5, 5.0 microgram/ml of pyridostigmine, and 0.8 microgram/ml of 4-AP combined with each of the above mentioned antiChEs were investigated. RESULTS: Whereas antiChE alone at low concentration partially recovered only the twitch response, 4-AP combined with antiChE recovered both the twitch and train-of-four responses significantly. CONCLUSIONS: 4-AP enhances antagonism of a magnesium-rocuronium induced neuromuscular blockade by edrophonium, neostigmine or pyridostigmine in vitro.
4-Aminopyridine* ; Animals ; Baths ; Cholinesterase Inhibitors* ; Edrophonium ; Neostigmine ; Neuromuscular Blockade* ; Oxygen ; Phrenic Nerve ; Pyridostigmine Bromide ; Rats