Evaluation of Muscle Relaxation by Tactile Posttetanic Count / 대한마취과학회지

The methods commonly used for monitoring neuromusculsr transmission do not allow evaluation of an intense neuromuscular blockade. Viby-Mogensen et al. introduced posttetanic count by which an intense nondepolarizing neuromuscular blockade can be evaluated, Our study was designed to evaluate whether the application of a tetanic stimulation (50 Hz for 5 sec.) every 6 to 10 minutes influences the recovery of neuromuscular transmission. 26 adult patients (ASA class I or II) were studied. They ranged in age from 20 to 71 years (mean 39.7 years). Anesthesia was induced with 0.1 mg/kg vecuronium and 4-5 mg/kg thiopental sodium and maintained with nitrous oxide and halothane. TOF group was stimulated with TOF stimulation only while PTC group with the pattern of stimulation introduced by Viby-Mogensen et al. In our results, the recovery time of PTC group was shorter than that of the TOF group. Therefore, our results indicate that intermittent tetanic stimulation (50 Hz for 5 sec.) every 6 to 10 minutes during intense non depolarizing neuromuscular blockade influences the time to the first response to TOF nerve stimulation.

Chest Wall Rigidity after Intravenous Administration of Fentanyl / 대한마취과학회지

Recently, fentanyl is frequently used for several purposes as an adjuvant during general anesthesia because of its potent analgesic action, rapid onset of action, short duration and minimal cardiovascular depression in the usual clinical dose. But it should be administered very carefully, because the occurrence of bradycardia and severe muscular rigidity are not uncommon. This report concerns a case of chest wall rigidity occurring in 16.8 kg, and 4-year-old boy after intravenous administration of 3 ug/kg fentanyl during mask inhalation anesthesia. The degree of rigidity was very severe and oxygen could not be inflated through the oxygen mask by manual method. The rigidity was relieved by a neuromuscular blocking agent.

Wolff-Parkinson-White Syndrome And Epidural Inhalation Anesthesia - A case report / 대한마취과학회지

The Wolff-Parkinson-White syndrome (WPW syndrome) and its variants are called the preexcitation syndrome. Anesthetic management of the patient with WPW syndrome requires the minimizing or avoidance of tachyarrythmias. Various anesthetic plans are employed for this purpose. For example, N2O, oxygen and narcotic technique, neuroleptanalgesia, deep inhalation anesthesia are included in this category. We have recently anesthetized a patient with preexcitation syndrome, performing continuous epidural anesthesia with 2% lidocaine and single bolus injection of Innovar followed by general endotracheal inhalation anesthesia with enflurane, and our experience suggested that this anesthetic method might be useful for the patients with WPW syndrome and below-lower abdomen operation.

Comparative Study of Vecurnium and Domestic Product of Vecaron in Human / 대한마취과학회지

The introduction of musele relaxants was an epoch-making event in the development of clinical anesthesia and their use has hecome essential to anesthesia practice. Vecuronium, one of the newest muscle relaxant, has many advantages; it is rapid and short-acting, noncumulative, has minimal side reactions and is promptly antagonized by anticholinesterases was introduced recently our clinical anesthesia practice. Fortunately, domestic product of vecuronium as vecaron was introduced lately. Therefore, this study was performed to evaluate the effects of vecaron and as compare with vecuronium. The results were as follows: 1) Similar effects of muscle relaxation was observed in both group except the onset time of twitch depression was shorter in vecuronium group than vecaron group. 2) Blood pressure and heart rate was increased during intubation in groups. 3) Recovery index was slightly prolonged in vecuronium group than vecaron group but no significance was observed. However, this recovery index of vecuronium was slightly shorter than previous observations.

Dose - Related Muscle Relaxation Effect of Atracurium in Rabbits / 대한마취과학회지

Atracurium, one of the newly developed nondepolarizing muscle relaxants, is remarkable due to the intermediate duration of action from the other previously known nondepolarizing agents and the broad safety margin in patients with renal or liver disease. There have been many reports suggesting that the pharmacologic effects of the nondepolarizing muscle relaxants are influenced by dosage. In this study, we attempted to identify the specific mechanism of muscle relaxation of atracurium. Particular attention was paid to the actually delivered atracurium dose and to the degree of muscle relaxation in rabbits. The results were as follows; 1) In the atracurium 0.4 mg/kg group, the onset of action was shortened and in the atracurium 0.6 mg/kg group, it was shortened more significantly. 2) The duration of action was increased with the increase of dose: the mean duration was 895 seconds in the atracurium 0.1 mg/kg group, 1,113.7 seconds in the 0.2 mg/kg group, and 1,199.3 second is in the 0.4 mg/kg group. It was prolonged to 1,730 seconds in the atracurium 0.6mg/kg group. 3) The spontaneous recovery index showed no differences in the atracurium 0.1 mg/kg group, 0.2 mg/kg group and 0.4 mg/kg group (196.7 sec., 195.0 sec, 202.7 sec. each). But in the atracurium 0.6 mg/ kg group, it was markedly prolonged to 334 seconds. In conclusion, atracurium, like other nondepolarizing agents, produces a dose related duration of action in muscle relaxation.

Changes of EKG & Arterial Blood Gas at Venous Air Embolism in Rabbits / 대한마취과학회지

After the hemodynamic comparison of venous air volume in 32 rabbits, the following conclusions were derived. 1) The precordial doppler ultrasonography was most sensitive and end titdal CO2 pressure was statistically decreased at 0.1 ml/kg of air. 2) The mean arterial pressure was suddenly decreased at 1 minute after injection of more than 0.25 ml/kg of air, and was furether reduced according to the time. 3) The arterial PCO2 was continuously increased and statistically different from 0.25 ml/kg of air, and the arterial PO2 was suddenly decreased to about 1/3 of the control data. 4) The pulse rate was statistically decreased at more than 0.5 ml/kg of air and shown peaked p wave, arrhythmias, ST depression and premature ventricular contraction on the EKG. There 4 dead rabbits at 1.0 ml/kg of air, so we could conclucle that the fatal dose of rabbits was more decreased than that of the dogs in venous air embolism.

The Changes of Serum Cholinesterase Activity in Term-Pregnant: In the Cesarean Section Patients / 대한마취과학회지

The serum cholinesterase level is influenced by a variety of disease states, especially in pregnancy as is well established now, although the reasons for the fall in the enzyme in certain conditions and its clinical significance are less clear. This known decrease in plasma cholinesterase activity could lead to the conclusion that the duration of paralysis from succinylcholine will be prolonged in pregnant patients. The purposes of this study were to evaluate the serum cholinesterase activity in nonpregnant women of the child-bearing age group and pregnant women and to evaluate the changes of serum cholinesterase following succinylcholine administration. The results were as follows: 1) The mean value of serum cholinesterase in 60 nonpregnant women of the child-bearing age group was 992.29-1,112.27 U/L. 2) The mean value of serum cholinesterase in 60 pregnant women was 769.40-826-27 U/L. 3) Pregnant women had a diminution of serum cholinesterase activity compared with nonpregnant women of the child-bearing age group, and this diminution was statistically very significant (p<0.01). 4) In Cesarean section patients treated with succinylcholine, there was further diminution of serum cholinesterase activity (P<0.01). With the above results, the possible clinical importance of marked diminution of a serum cholinesterase activity in pregnant women is outlined.

Incidence of Cardiac Arrhythmias during anesthesia / 대한마취과학회지

The incidence of cardiac arrhythmias during anesthesia in a total 5,845 surgical patients who were admitted to Hanyang university hospital from Janury 1 to December 31, 1988 was investigated using on-line continuous EKG monitoring. The results were as follows: 1) Among study patients, 111 patients (1.9%) had pre-existing cardiac arrhythmias before anesthesia and showed significantly higher incidence of arrhythmias (49.5%) than that of patients without pre-existisng arrhythmias before anesthesia (2.9%). 2) Among arrhythmias found during anesthesia, most types of arrhythmias were ventricular premature contractions (77.4% in the patients with pre-existing cardiac arrhythmias and 43.6% in the patients without pre-existing cardiac arrhythmias) except sinus bradycardia and tachycardia. 3) Although the incidence of arrhythmias during the induction of anesthesia was similar to that during anesthesia maintenance, it was somewhat greater on the basis of incidence per unit time. 4) The incidence of arrhythmias was increased with age. 5) The incidence of arrhythmias when anesthesia was induced with halothane (3.7%) was greater than that when anesthesia was induced with enflurane (2.1%). 6) Most of the arrhythmias were controlled with sufficient ventilation and oxygen supply, adjusting concentration of inhaled anesthetics or changing anesthetics, and occasionally, intravenous admininstration of 1% lidocaine (1.0-1.5 mg/kg). Considering the above results, it may be an appropriate conclusion that the continuous on-line EKG monitoring during the induction and maintenance of anesthesia is a noninvasive and simple method for detecting early signs of cardiac arrhythmias and hemodynamic changes during anesthesia, and consequently, improving the overall efficiency of patient care. Therefore, we are impressed with an idea that the continuous EKG monitoring should be mandatory for all surgical patients to be anesthetized.