Enflurane* ; Metabolism* ; Methoxyflurane* ; Panax*

We chose enflurane as the primary anesthetic agent for the surgical removal of a pheochromocytoma (23 year old male) with the satisfactory results. A review of the literature on the anesthetic management of pheochromocytoma discloses no general agreement regarding choice of an anesthetic agent. Almost all agents have at some time been both praised and rejected. It would suggest that selection of an anesthetic agent is not as important as the adequate management of that agent.
Anesthesia* ; Enflurane* ; Pheochromocytoma*

BACKGROUND: The purpose of this study was to evaluate the safety and efficacy of low-flow anesthesia with a semi-closed circle anesthesia system in infants. METHODS: Twenty, ASA physical status 1 or 2, infants were randomly assigned into two groups: high-flow anesthesia (HFA) or low-flow anesthesia (LFA). An identical semi-closed Dr ger circle anesthesia system (Cato) was used to all patients. Initial fresh gas flow (FGF) was N2O 1.5 L/min and O2 1.5 L/min in both groups. This FGF of 3 L/min was maintained in the HFA group. After 10 min of HFA, the FGF was reduced to 500 ml/min (N2O 250 ml/min and O2 250 ml/min) in the LFA group. RESULTS: Hypoxic or hypercarbic gas concentrations were not observed in all patients. Enflurane consumption during LFA was about 1/3 of that during HFA (6.8 +/- 1.3 ml vs. 19.5 +/- 5.8 ml). The mean highest esophageal temperature was similar in both groups. The mean highest inspiratory gas and soda lime temperatures were significantly higher in the LFA group than in the HFA group. CONCLUSIONS: Low-flow anesthesia in a circle system with a fresh gas flow of N2O 250 ml/min and O2 250 ml/min could be performed safely and economically for infants.
Anesthesia* ; Enflurane* ; Humans ; Infant*

Plasma inorganic fluoride concentrations were measured in adult patients without hepatic or renal disease following sevoflurane-N2O anesthesia (n=7) or enflurane-N2O anesthesia (n=6). The anesthetic dosage of sevoflurane and enflurane was 6.48+/-2,15%-hour and 6.57+/-2.05%-hour, respectively. The mean peak plasma inorganic fluoride concentration in the sevoflurane group was 19.5+/-13.4 umol/L 1hour after anesthesia, which decreased to preanesthetic levels 24 hours after anesthesia. In the enflurane group the values were 13.2+/-5.8 umol/L at the end of anesthesia and decreased, but remained, still twice as high as the preanesthetic level 24 hours after anesthesia. The relationship of plasma inorganic fluoride concentration and anesthetic dosage was more pronounced in the sevoflurane group (r=0.68, slope=4.2) than in the enflurane group (r=0.39, slope=1.2). In conclusian, sevoflurane-N2O anesthesia results in similar subnephrotoxic levels of plasma inorganic fluoride as enflurane-N2O. anesthesia, and although the fluoride concentration had a better correlation to anesthetic dosage in the sevoflurane group than in the enflurane group, its excretion was faster in the sevoflurane group than in the enflurane group.
Adult ; Anesthesia* ; Enflurane ; Fluorides* ; Humans ; Plasma*

Observation of changing pattern of blood pressure and pulse rate of enflurane anesthesia for 200 cases operations, performed during the past 4 years (1983~1986) in Yeungnam University Hospital have been evaluated clinically. In order to observe the influence of enflurane upon the blood pressure and pulse rate during general anesthesia, the authors prepared a formula, expressing changing of blood pressure and pulse rate by time series and analyzed the types and distribution pattern in the experiment. The results obtained were as follows: 1. Blood pressure and pulse rate were increased at the time of intubation. 2. Generally, blood pressure and pulse rate were increased at the time of intubation and then stabilized within 20 minutes. 3. Most common patterns were identified. ADEE type was 73~74%, which is most common type and AEEE type was about 40%.
Anesthesia* ; Anesthesia, General ; Blood Pressure* ; Enflurane* ; Heart Rate* ; Intubation

BACKGROUND: A circle system can be closed or semiclosed depending on the amount of fresh gas flow. A closed system is one in which the inflow gas exactly matches that being taken up or consumed by the patient. A semiclosed system is associated with partial rebreathing of gases and is the most commonly used system today. The purpose of this study is to examine the actual consumed amount of volatile anesthetic by closed and semiclosed anesthesia systems. METHODS: Forty-seven patients undergoing general inhalation anesthesia with enflurane and thirty-six patients with isoflurane were examined. Each group was divided into two subgroups by the circle system; enflurane-closed (33 patients), enflurane-semiclosed (14 patients), isoflurane-closed (23 patients), and isoflurane-semiclosed groups (13 patients). Closed system was performed by using PhysioFlex anesthesia machine. The difference of initial (just before anesthesia) and remained (just after anesthesia) enflurane or isoflurane volumes measured by 30 ml-syringe was obtained as consumed amount of anesthetics. This amount was calculated on the base of 1% enflurane or isoflurane for 1 hour anesthesia with a given fresh gas flow (4 to 5 L/min). RESULTS: Consumed amount of liquid enflurane and isoflurane when using closed system was 6.99 +/- 0.26 ml/hr and 4.84 +/- 0.27 ml/hr respectively while 15.99 +/- 1.48 ml/hr and 14.01 +/- 0.92 ml/hr respectively when using semiclosed system. Consumption of liquid anesthetics was significantly lower in closed anesthesia and significantly higher in both systems than those of predicted values. CONCLUSIONS: In closed system by using PhsioFlex anesthesia machine consumed amount of liquid anesthetic for 1 hour anesthesia with 1% of endtidal anesthetic concentration at 25 degrees C, 1 atm and 4 to 5 L/min of fresh gas flow was within 35 to 44% of that in semiclosed system.
Anesthesia* ; Anesthesia, Inhalation ; Anesthetics* ; Enflurane ; Gases ; Humans ; Isoflurane

In order to observe the effect on liver function after exposure to enlurane which has relatively minimal hepatotoxic effect, we evaluated the changes of the s-GOT & s-GPT levels caused by general anesthesia with enflurane. This study was undertaken to evaluate the effect of enflurane on liver function by comparing the preoperative and postoperative(1st day, 3rd day, 5th day, and 7th day) liver function(s-GOT & s-GPT) tests is il cases of the first general anesthesia with enflurane and 15 cases of a second general anesthesia with enflurane. The results were as folllows: 1) The 1st operative group. a. There are 5 cases (45%) of significant changes of s-GOT levels and no case of significant change in sGPT levels. b. In most of cases, the level of s-GOT & s-GPT have returned to normal values on the 7th postoperative day. 2) The 2nd operative group. a. The increase in the levels of s-GOT was found in 10 cases, and the s-GPT in 6 cases. b. Postoperatively, the simultaneous increase in the levels of s-GOT & s-GPT were found in 4 cases. c. On the 7th postoperative day, the levels of s-GOT & s-GPT was not normal in 3 cases, and not normal for s-GPT in 2 cases. The above results show that the higher of levels of s-GOT & s-GPT after the second general anesthesia with enflurane apparent compared to the levels after the first general anesthesia with enflurane. And it can be assumed that the extreme precaution is necessary in conduction the second general anesthesia with enflurane.
Alanine Transaminase ; Anesthesia, General ; Enflurane* ; Liver ; Reference Values

There are many disease entities which are associated with hemoglobinuria but the report of which is very rare during anesthesia except in the case of incompatible transfusion. The authors experienced a case of severe hemoglobinuria during general anesthesia with halothane, nitroud oxide, and thiopental sodium. The patient had no transfusion perioparatively, and no history of hemoltic problems except for prolonged oozing after ethrane anesthesia for tympanoplasty five monthes ago previously. The hemogiobinuria disappeared after two days of corticosteroid therapy, but afterwards the patient suffered from mild hepatitis which seemed to be due to repeated halothane anesthesia.
Anesthesia ; Anesthesia, General* ; Enflurane ; Halothane ; Hemoglobinuria* ; Hepatitis ; Humans ; Thiopental ; Tympanoplasty

BACKGROUND: The bispectral index (BIS) has been designed to objectively measure the degree of sedation and hypnosis for anesthesia. Although it has been well-known that BIS correlates highly with the concentration of inhalation anesthetics, it is not clear whether analgesic potency expressed as MAC is comparable to hypnotic potency described as BIS50 in inhaled anesthetics. This study was conducted to examine the degree of correspondence by correlating the changes of BIS according to the different MAC of commonly used inhalation anesthetics. METHODS: One hundred ASA class 1 or 2 patients, scheduled for laparoscopic knee surgery were included. Patients were equally divided into 4 groups (n = 25 each) according to the inhalational agent enflurane, isoflurane, desflurane, or sevoflurane. Anesthetic depth for each individual agent was controlled to 2.0, 1.75, 1.5, 1.25, 1.0, 0.75 and 0.5 MAC, respectively. After equilibration for each concentration, BIS values were measured three times at 30 second intervals and an average was obtained. In addition, MAC values for each agent were measured when the bispectral index showed 50. RESULTS: The concentrations of inhaled agents vs. BIS showed high negative correlations (enflurane; -0.91, isoflurane; -0.94, desflurane; -0.84, and sevoflurane; -0.86). BIS50 for each agent was enflurane, 0.93 (1.6 vol%); isoflurane, 0.71 (0.9 vol%); desflurane, 0.95 (5.7 vol%); and sevoflurane, 0.84 MAC (1.7 vol%). Isoflurane-BIS50 showed a significant difference to the others (P<0.05). CONCLUSIONS: We concluded that the MAC of inhalation anesthetics showed poor correlation with BIS, suggesting a difference between the hypnotic and analgesic potency of individual inhaled anesthetic agents.
Anesthesia ; Anesthetics ; Anesthetics, Inhalation* ; Enflurane ; Humans ; Hypnosis ; Inhalation* ; Isoflurane ; Knee

BACKGROUND: We examined the use of DFA-Detrended fluctuation analysis-of heart rate variability during general anesthesia in order to assess the depth of anesthesia. METHODS: In this study, we observed changes in alpha1, the short range scaling exponent, in alpha2, the long range scaling exponent, and in the alpha2/alpha 1 ratio during enflurane anesthesia. We monitored 7 stages during general anesthesia, i.e., 1) preoperation (awake state), 2) during induction, 3) after induction, 4) during maintenance, 5) before extubation, 6) after extubation, and 7) postoperation (Next day). RESULTS: The alpha 2/alpha 1 ratio increased during the induction and extubation state compared to preoperation (awake state). This may be related to increased sympathetic activity due to stimulation of the autonomic nervous system. In the postoperation (awakened state), the ratio returned to the preoperation value (awake state). These results are similar to low frequency (LF), high frequency (HF) and LF/HF ratio values which reflect activity of autonomic nervous system. CONCLUSIONS: Detrended fluctuation analysis parameters, especially the alpha 2/alpha 1 ratio, would be used for monitoring the depth of anesthesia. Also these parameters are useful indexes with the LF/HF ratio for the evaluation of sympathetic activity during general anesthesia.
Anesthesia* ; Anesthesia, General ; Autonomic Nervous System ; Enflurane ; Heart Rate