Background and Objective: Due to the high cost of scavenging systems, it is rare to find them in use in the hospitals of developing countries. This study was designed to determine the efficacy of a modified scavenging system for isoflurane for use in the Philippines Material and Methods: A modified scavenging system was constructed using a 500 ml of beaker glass with 100 ml of tap water, the opening tightly sealed with styropore. A single anesthesia machine, gas analyzer and isoflurane vaporizer were used in this study. Oxygen flow was set at one liter per minute. The isoflurane vaporizer was set at 2.5 volume percent. A corrugated tube conveys wasted gas into the beaker and allows the gas to bubble through the tap water. Another tube conveys bubbled gas from the beaker to the atmosphere. As soon as there is no change for at least 15 seconds in the numeric value and graphical representation of the MAC and volume percent of isoflurane in the gas analyzer, the reading was recorded as MAC-O minute and volume percent-0 minute. This was repeated every 15 minutes thereafter in the inlet port and every five minute in exit port until 60 minutes Results: The mean MAC and volume percent of isoflurane at point A and B were 1.1 versus 0.938461538 and 1.3 versus 1.158974359, respectively (t-test p0.05). At point B, all observation was statistically lower than the baseline (t-test p0.05) Conclusion: The MAC and volume percent of isoflurane were statistically lower at point B from 0 observation time until 60 minute observation time using the modified scavenging system. (Author)
ANESTHESIA, ISOFLURANE

BACKGROUND: One way to make rapid increase in alveolar anesthetic concentration includes using high fresh gas flow rates. Fresh gas flow rates should be increased to compensate the amount of uptake either. This study was performed to elucidate optimal fresh gas flow rates for rapid induction by comparison of changes of ratio of expired to inspired concentration. METHODS: The study population was composed of 107 patients undergoing thyroidectomy. Patients were randomly allocated to one of three groups who received desflurane or sevoflurane or isoflurane. Each group was randomly subdivided into three groups who received one of the fresh gas flow rate: 2, 5 or 10 L/min. Inspired anesthetic concentration (Fi) and expiratory anesthetic concentration (Fe), delivered concentration (FD) were recorded. RESULTS: With same fresh gas flow rates, there were significant differences between Fe/Fi of desflurane, sevoflurane, isoflurane. With same anesthetics, Fe/Fi of desflurane and sevoflurane were not influenced by fresh gas flow rates. But Fe/Fi of isoflurane at 2 L/min was significantly lower than 5 L/min and 10 L/min. Fi/FD of desflurane at 10 L/min did not differ from sevoflurane. At 2 L/min and 5 L/min, Fi/FD of desflurane was highest and then sevofluane, isoflurane in that order. CONCLUSIONS: Because rates of Fe/Fi of desflurane and sevoflurane were not influenced by fresh gas flow rates, 2 L/min of fresh gas flow rates could be selected. However, considering the wash-in time in circuit, optimal choice of fresh gas flow rate for desflurane and sevoflurane could be 5 L/min, that of isoflurane be 10 L/min.
Anesthetics ; Humans ; Isoflurane ; Thyroidectomy

To determine the minimum alveolar concentration (MAC) of isoflurane in korean children, 33 children (preschool age group ; 17, school age group ; 16) were anesthetized with isoflurane in 100% oxygen. The move-no move responses to skin incision were recorded, and MAC was determined using the Litchfield-Wilcoxon method. MAC of isoflurane was determined in two pediatric age groups. MAC was 1.35% in preschool age group (10 month~7,5 yr of age), 1.37% in school age group (8~14 yr of age), 1.36% in all children (10 month~14 yr of age).
Child* ; Humans ; Isoflurane* ; Oxygen ; Skin

Sevoflurane, a volatile halogenated ether, has been widely used in the conduct of anesthesia. Its potency, easy titratability, less pungency and rapid recovery are the reasons for its pervasive use in clinical practice. However, it is not without adverse effects. The nephrotoxicity associated with its use has been the subject of dispute over the years. At present, no highly sensitive renal marker has been the subject of dispute over the years. At present, no highly sensitive renal marker has been utilized to assess renal function. Objective: To compare the effect on renal function as measured by nuclear glomerular filtration rate, serum creatinine, urine protein creatinine ratio, proteinuria and glocosuria of sevoflurane with isoflurane in patients undergoing donor nephrectomy. Study Design and Methods: A randomized comparative study of postoperative renal functions as measured by nuclear glomerular filtration rate, serum creatinine, urine protein creatinine ratio, proteinuria and glucosuria in patients undergoing donor nephrectomies who have received low flow (<1 L/Min) sevoflurane or isoflurane were done. Results: A total of 102 kidney donors met the inclusion criteria. Forty seven subjects (46%) were randomized to receive isoflurane while 55 received sevoflurane (54%). Most subjects were in the third decade of life. There was no statistically significant difference between the two groups in terms of the baseline clinical characteristics. Comparing between the two anesthetic groups, there was no significant difference in terms of serum creatinine, total GFR, nuclear GFR per kidney. There was a statistically higher proportion of patients with urine protein- creatinine ratios of 0.2 and above in the isoflurane group (64% versus 38%) while more patients in the sevoflurane group had ratios above 0.2 (62% versus 36%, p=.045). The type of anesthetic agent was not an independent predictor of increasing serum creatinine, total GFR and urine protein- creatinine ratio and nuclear GFR assessed per kidney. Conclusion: There were no statistical differences noted in measured renal function parameters among patients undergoing donor nephrectomy after low flow sevoflurane compared with isoflurane anesthesia. These results suggest that low flow sevoflurane is as safe as low flow isoflurane and does not alter renal functions in patients for donor nephrectomy.
Human ; SEVOFLURANE ; NEPHRECTOMY ; ANESTHESIA ; ISOFLURANE

No abstract available.
Depression* ; Isoflurane* ; Nitrous Oxide* ; Scopolamine Hydrobromide*

BACKGROUND: This study was doned to evaluate the rate of awakening after desflurane or isoflurane anesthesia in pediatric tonsillectomy patients. METHODS: Sixty patients, aged 5 10 years undergoing a tonsillectomy with or without an adenoidectomy were randomly assigned to receive either desflurane-N2O (group D) or isoflurane-N2O (group I). A recovery profile was assessed by a 3 point scale for the first 0, 15 and 30 min in the recovery room. RESULTS: It was statistically significant that group D had a shorter extubation time and eye opening time and a less apprehensive score than group I at 0, 15 and 30 min. CONCLUSIONS: We conclude that desflurane-N2O may offer clinical advantages over isoflurane when used for maintenance of anesthesia during a pediatric tonsillectomy.
Adenoidectomy ; Anesthesia ; Humans ; Isoflurane ; Recovery Room ; Tonsillectomy*

Since Steven(1971) introduced the cardiovascular effects of isoflurane many characteristics of isoflurane were reported. Among many advantages of isoflurane its limited metabolism in the body results least effect on the liver. In order to compare the effects isoflurane and halothane on liver function in five each gynecologic patient with normal liver function test(LFT), we checked liver function preoperatively as control and postoperative 7th day as experiment. We also studied the effects of isoflurane on liver function in patients with abnormal LFT. The results were as follows: First, there were no difference on the effect of LFT between halothane and isoflurane in patient with preoperatively normal LFT. Second, inhalation of isoflurane in patient with abnormal LFT does not seem to worsen liver function furthermore.
Anesthetics ; Halothane ; Humans ; Inhalation ; Isoflurane* ; Liver* ; Metabolism

Objective To study the influence of halogenated hydroxyl-alkanes inhalation anesthetic on the determination of ethanol content in blood. Methods Halogenated hydroxyl-alkanes were analyzed by headspace gas chromatography with double column confirmatory detection method. The influence of halogenated hydroxyl-alkanes on determination of ethanol content in blood sample by headspace gas chromatography was explored under the different detection conditions of KB-BAC1/ KB-BAC2 and J&W DB-ALC1/DB-ALC2 gas chromatographic column. Results The retention time of sevoflurane and enflurane was similar to that of ethanol and tert butanol respectively when using the J&W DB-ALC1/DB-ALC2 gas chromatographic column, and interfered with the detection of ethanol content in blood; only J&W DB-ALC1 gas chromatographic column can separate the sevoflurane and ethanol components, so as to eliminate their influence on the detection of ethanol content in blood. When using KB-BAC1/KB-BAC2 gas chromatographic column, the retention time of sevoflurane, isoflurane and ethanol is similar, especially that of sevoflurane and ethanol, and sevoflurane obviously interferes with the determination of ethanol content in blood. Conclusion Halogenated hydroxy-alkanes interfere with determination of ethanol content in blood by headspace gas chromatography. The interference can be discriminated effectively by choosing the suitable chromatographic column and double column confirmatory detection.
Alkanes ; Anesthetics, Inhalation ; Ethanol ; Isoflurane ; Sevoflurane

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: Monitoring of "Depth of anesthesia" is an ongoing problem in anaesthesia. In this study, the author has compared the bispectral index (BIS) and Anemon monitor for monitoring depth of anesthesia in propofol or isoflurane anesthesia. METHODS: Anemon-1 and BIS index were obtained from 24 patients (ASA I, II) during general anesthesia with propofol or isoflurane. For patients in the propofol group, anesthesia was induced with fentanyl 100ng followed by propofol 2 mg/Kg. For patients in the isoflurane group, anesthesia was induced with thiopental 5 mg/Kg. The author observed changes of these values at 5 major times: before induction, during induction, after induction, at sKin incision, before extubation, after extubation. RESULTS: The anemon index showed a significant increase during induction (propofol group: 86.9 +/- 26.4, isoflurane group: 106.0 +/- 18.6) and at sKin incision (propofol group: 89.9 +/- 22.7, isoflurane group: 92.0 +/- 23.1), but this did not correlate with the level of consciousness. The BIS index showed a significant decrease in the score after induction (propofol group: 55.0 +/- 9.6, isoflurane group: 61.0 +/- 17.2), but no response to surgical stimuli. CONCLUSIONS: BIS had a good correlation with level of consciousness. The Anemon-1 index was recognized to reflect invasive stimulus. As the BIS and Anemon-1 had no correlation, it was not possible to assume changes of each index from the other. Both the anemon-1 index and BIS are useful to monitor the anesthesia level during surgery.
Anesthesia ; Anesthesia, General ; Consciousness ; Fentanyl ; Humans ; Isoflurane ; Propofol ; Skin ; Thiopental