Background: Esmolol is rapid hydrolyzed by plasma esterase but may inhibit plasma cholinesterase activity based on its structure. This study was designed to evaluate the interactions between esmolol and succinylcholine or mivacurium which are metabolized by plasma cholinesterase and to determine the inhibitory effect of esmolol on human plasma cholinesterase. Methods: Neuromuscular effects of succinylcholine (1.0 mg/kg) and mivacurium (0.15 mg/kg) with or without esmolol (0.5 mg/kg or 1.0 mg/kg) were compared in 57 adult patients (ASA class I) during O2-N2O-isoflurane anesthesia. Neuromuscular block was monitored by recording the compound electromyogram of the hypothenar muscle resulting from supramaximal train of four stimuli applied to the ulnar nerve. Also plasma cholinesterase activity was measured before and 5, 10 minutes after injection of esmolol. Results: Time from injection to onset of over 95% block, clinical duration from injection to 25% recovery of control twitch, and recovery index defined as from 25% to 75% twitch recovery of succinylcholine or mivacurium were not altered by pretreatment of esmolol. Plasma cholinesterase activity was not decreased after injection of esmolol 0.5 mg/kg, but decreased by 5% after injection of 1.0 mg/kg (p<0.05). Conclusions: It is unlikely that neuromuscular blocking effects of succinylcholine and mivacurium are prolonged by administration of clinical doses of esmolol (0.5~1.0 mg/kg) due to inhibition of plasma cholinesterase activity in human.
Adult ; Anesthesia ; Cholinesterases ; Humans ; Neuromuscular Agents ; Neuromuscular Blockade ; Plasma ; Succinylcholine* ; Ulnar Nerve

BACKGREOUND: The magnitude of neuromuscular blockade is related to plasma concentration of muscle relaxants. This study was designed to compare the maximal depression of twitch height by blood flow occlusion using a tourniquet at various time interval after intravenous administration of muscle relaxants. METHOD: We studied 127 healthy male adult patients who underwent elective surgery under the general anesthesia with propofol infusion and 50% nitrous oxide. The single supramaximal twitch stimulation applied to the ulnar nerve at the wrist at 1 Hz. The twitch response of adductor pollicis muscles were measured by a 2 kg Load Cell strain gauge with a thumb piece modification and recorded by a Gould TA 240 recorder. After occlusion of blood flow by the tourniquet in the upper arm, in which the neuromuscular monitoring was applied on the wrist, we administered the equipotent dose (ED95) of succinylcholine (S group), mivacurium (M group), and vecuronium (V group) intravenously on the contralateral arm respectively. We measured the maximal depression (%) of twitch height after the releasing tourniquet at 30, 60, 90, 120, 150, and 240 second intervals after the injection of each drug. RESULTS: The depression of twitch height was not found from 90 seconds of tourniquet time in the M group, and 120 seconds of tourniquet time in the S group. However, in the V group, the depression of twitch height was maintained to 240 seconds of tourniquet time. CONCLUSIONS: It is suggested that the plasma concentration of mivacurium declined faster than that of succinylcholine, and that of vecuronium decreased slowest among the groups after intravenous administration of equipotent dose (ED95).
Administration, Intravenous ; Adult ; Anesthesia, General ; Arm ; Depression ; Forearm* ; Humans ; Male ; Muscles ; Neuromuscular Agents* ; Neuromuscular Blockade ; Neuromuscular Monitoring ; Nitrous Oxide ; Plasma ; Propofol ; Succinylcholine* ; Thumb ; Tourniquets ; Ulnar Nerve ; Vecuronium Bromide* ; Wrist

OBJECTIVES: We tested the reliability and validity of the Korean version of the PANSS (PANSS-KV). METHODS: The PANSS ratings were obtained from 101 subjects with DSM-IV diagnoses of schizophrenia or schizophreniform disorder. To study the concurrent validity, the Scale for the Assessment of Positive Symptoms (SAPS) and the Scale for the Assessment of Negative Symptoms (SANS) were also administrated in 38 patients. Using these data, inter-rater reliability, test-retest reliability, internal consistency, criterion validity and concurrent validity were evaluated. Factor structure was analyzed by the principal axis factoring. RESULTS: The inter-rater reliability of the Korean version of the PANSS was satisfactory in positive (r=0.92) and negative syndrome subscales(r=0.86), but somewhat low in general psychopathology subscale (r=0.78). The test-retest correlations for the 3 PANSS subscales ranged between 0.89 and 0.95, so it showed excellent test-retest reliability. The Cronbach's alpha for the positive, negative and general psychopathology subscales were 0.73, 0.84 and 0.74, respectively and thus the 3 subscales of the PANSS had good internal consistencies. All separate items revealed significant corrected item-total correlations in the positive and negative syndrome subscales, but some items of the general psychopathology subscale showed no or low corrected item-total correlations. The positive and negative syndrome subscales held a high concurrent validity in relation to the SAPS and the SANS. It was confirmed that positive and negative syndromes were independent constructs. The factor analysis by the principal axis factoring produced 5 components: cognitive, excitement, depression, positive and negative. CONCLUSION: These findings prove that the reliability and validity of the PANSS-KV are comparable to those of the original PANSS. So, the PANSS-KV can be widely and extensively used in researches for schizophrenia.
Axis, Cervical Vertebra ; Depression ; Diagnosis ; Diagnostic and Statistical Manual of Mental Disorders ; Humans ; Psychopathology ; Psychotic Disorders ; Reproducibility of Results* ; Schizophrenia