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*

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*

Enflurane* ; Metabolism* ; Methoxyflurane* ; Panax*

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*

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

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

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: There are many factors including the operation site, duration of anesthesia, preoperative liver function and hepatitis, which cause postoperative hepatic dysfunction. The purpose of this study is to evaluate postoperative liver function with respect to a history of alcohol intake. METHODS: Seventy-five patients were divided into 2 groups:44 patients without alcohol intake (non-alcohol group), 31 patients with alcohol intake (alcohol group). All patients were anesthetized with about 1.5 vol% of enflurane combined with 50% nitrous oxide and 50% oxygen. AST (aspartate aminotransferase) and ALT (alanine aminotransferase) were measured before anesthesia, 1, 3 and 7 days after surgery in both groups, respectively. Postoperative AST and ALT values were compared to preoperative values within each group, and were also compared between groups. RESULTS: In the alcohol group, postoperative AST and ALT values were significantly higher than preoperative values (P < 0.05). In addition, postoperative ALT values significantly increased in the 1st and 7th day over the upper normal limit of ALT (P < 0.05). In the non-alcohol group, postoperative AST and ALT values increased over preoperative values, but those levels were within the normal limits of AST and ALT. CONCLUSIONS: The data suggest that when surgery can reduce hepatic blood flow, patients with a history of alcohol ingestion may have a risk of raised liver-derived enzyme in the first seven postoperative days.
Anesthesia* ; Eating* ; Enflurane* ; Gastrectomy* ; Hepatitis ; Humans ; Liver ; Nitrous Oxide ; Oxygen

N2O can diffuse in and/or out the middle ear cavities and it may alter the middle ear pres-sure. This study was performed to investigate the effect of N2O discontinuation on the changes in middle ear pressure during general endotracheal anesthesia. We measured middle ear pres-sures and end-tidal NO concentrations at preanesthesia, immediately after N2O discontinuation and then at every five minutes for 60 minutes under either halothane or enflurane an- esthesia in two groups(group 1=50% administration of N2O in O2; group 2=60% administration of N2O in O2). The middle ear pressures after N2O discontinuation decreased slowly but they did not returned to the preanesthetic value in both groups. The end-tidal N2O concentrations decreased rapidly until five minutes and then they decresed slowly to the zero leve1 until 30 minutes after N2O discontinuation in both groups. The expected time of the middle ear pres-sure of preanesthesia value was 89.4 minutes in group 1 and 80.9 minutes in group 2 respectively. The middle ear pressure do not return to the level of preanesthesia at 60 minutes after N2O discontinuation while the end-tidal N2O concentration decrease to the zero level via 30 minutes after its discontinuation. Thus it is recommended that N2O administration should be discontinued at least 30 minutes before an application of tympanic membrane patch on the ear drum and N2O is carefully administered in patients with middle ear and/or upper airway disesses.
Anesthesia* ; Ear ; Ear, Middle* ; Enflurane ; Halothane ; Humans ; Tympanic Membrane

N2O can diffuse in and/or out the middle ear cavities and it may alter the middle ear pres-sure. This study was performed to investigate the effect of N2O discontinuation on the changes in middle ear pressure during general endotracheal anesthesia. We measured middle ear pres-sures and end-tidal NO concentrations at preanesthesia, immediately after N2O discontinuation and then at every five minutes for 60 minutes under either halothane or enflurane an- esthesia in two groups(group 1=50% administration of N2O in O2; group 2=60% administration of N2O in O2). The middle ear pressures after N2O discontinuation decreased slowly but they did not returned to the preanesthetic value in both groups. The end-tidal N2O concentrations decreased rapidly until five minutes and then they decresed slowly to the zero leve1 until 30 minutes after N2O discontinuation in both groups. The expected time of the middle ear pres-sure of preanesthesia value was 89.4 minutes in group 1 and 80.9 minutes in group 2 respectively. The middle ear pressure do not return to the level of preanesthesia at 60 minutes after N2O discontinuation while the end-tidal N2O concentration decrease to the zero level via 30 minutes after its discontinuation. Thus it is recommended that N2O administration should be discontinued at least 30 minutes before an application of tympanic membrane patch on the ear drum and N2O is carefully administered in patients with middle ear and/or upper airway disesses.
Anesthesia* ; Ear ; Ear, Middle* ; Enflurane ; Halothane ; Humans ; Tympanic Membrane