We have used mivacurium in two myasthenic patients, a generalized myasthenia gravis (MG) patient presenting for thymectomy and a Lambert-Eaton myasthenic (LEM) patient for mediastinoscopic lymph node biopsy. Both of them received nitrous oxide/oxygen (1:1)-narcotic-enflurane anesthesia with mivacurium as a muscle relaxant and the neuromuscular blocking effect of mivacurium was monitored continuously through the operation as well as before the induction of anesthesia. The dose of mivacurium for MG patient was 5.5 mg and LEM patient was 12 mg, because MG patient showed more severe clinical symptoms. The response to train-of-four (TOF) ulnar nerve stimulation was recorded using accelography. The onset times to maximal block in MG and LEM patients were 30 and 120 sec, respectively after injection and the recovery times to 25% from maximal block were 117 and 76 min, respectively. Mivacrium would be safe and appropriate for use in myasthenic patients, with relatively small dose under the neuromuscular monitoring.
Anesthesia ; Biopsy ; Humans ; Kinetocardiography ; Lymph Nodes ; Myasthenia Gravis ; Neuromuscular Blockade ; Neuromuscular Monitoring ; Thymectomy ; Ulnar Nerve

The abnormalities of left ventricular ejection patterns have been studied using echocardiography, contrast angiography, radionuclide angiography, and apex cardiography in patients with various heart disease. Recently it has been recognized that diastolic impairment may occur in the absence of abnormal systolic performance in hypertension, valvular heart disease, ischemic heart diseases, and cardiomyopathies. In order to identify whether diastolic dysfunction can develop without systolic dysfunction, we evaluated patterns of left ventricular filling and ejection by echocardiography in 10 chronic mitral regurgitations without pulmonary congestion symptom, who were confirmed by cardiac catheterization. Indices of left ventricular systolic function, including ejection fraction, fractional shortening, ejection rate, mean velocity of circumferential fiber shortening, and preejection period/left ventricular ejection time revealed no significant difference in mitral regurgitation patients compared with normal control group. Diastolic parameters, including atrial emptying index,mean velocity of circumferential fiber lengthening, rapid filling period, and rapid filling velocity were changed significantly in mitral regurgitation. There were no significant alterations in blood pressure and heart rate between two groups. It is concluded that impaired diastolic performance may be frequently encountered in patients with chronic mitral regurgitation and intact systolic function.
Angiography ; Blood Pressure ; Cardiac Catheterization ; Cardiac Catheters ; Cardiomyopathies ; Echocardiography ; Estrogens, Conjugated (USP) ; Heart Diseases ; Heart Rate ; Heart Valve Diseases ; Humans ; Hypertension ; Kinetocardiography ; Mitral Valve Insufficiency* ; Myocardial Ischemia ; Radionuclide Angiography ; Ventricular Function, Left*