1.Spectrum Analysis of Rat EEG during Infusion of Thiopental and Ketamine.
Suk Tae CHO ; Mann Gee LEE ; Choong Young KIM
Korean Journal of Anesthesiology 1992;25(4):639-647
The dose-ralated dffects of intravenous infusion of thiopental and ketamine on the rat EEG were evaluated quantitatively by spectrum analysis of EEG recorded from the rat scalp. The anesthetics were infused into jugular vein at various rates ranging from 0 to 8ug/min/g body weight, and then bipolar EEG was recorded from the rat scalp and tis spectrum were calculated by powere wpectrum analysis. the density of each bands(delta 1-3.25, theta 3.5-7.75, alpha 8-12.15, beta 1.13-17.75, beta 2.18-20.75, and beta 3.21-31.75Hz) and total density were derived from the spectrums. In visual inspection of conventional EEG, low doses of thiopental increased the amplitudes of spinles. but higher doses decreased the amplitube gradually to electrical silence with increase of infusion rates. During infusion of higher doses of ketamine, two types of EEG were identified by the spectral patterns:The one was the cases in which increases of the power density over all frequency ranges were observed, and the other was those in which marked increases of density in specific frequency were observed. In thiopental infusion, the densities of all bands were increased to peak at 1~2ug/min/g and therafter were decreased with higher rates of infusion. In ketamine infusion, the densities were increased when the infusion rate was increased. These results suggest that, by the changing patterns of the band densities dervied from spectrum analysis of EEG, not only the effect on EEG of thiopental of tetamine can be quantified but also their differences of mechanisms of action on brain be reflected.
Anesthetics
;
Animals
;
Body Weight
;
Brain
;
Electroencephalography*
;
Infusions, Intravenous
;
Jugular Veins
;
Ketamine*
;
Rats*
;
Scalp
;
Spectrum Analysis*
;
Thiopental*
2.Evaluation of Anesthetic Effects of Enflurane by Spectrum Analysis of Rat EEG.
Mann Gee LEE ; Woon Yi BAEK ; Byung Kwon KIM ; Choong Young KIM
Korean Journal of Anesthesiology 1992;25(4):648-655
To evaluate the depth of enflurane anesthesia, spectrum analysis of rat EEG was used. Bipolar EEG was recorded through one lead form rat scalp during inhalation with 1,2,3 and 4% of enflurane, and analysed to produce the spectrum from which the density of each band(delta 1-3.25Hz, theta 3.5-7.75Hz, alpha 8-12.75Hz, beta2 18-20.75Hz, and beta3 21-31.75Hz)and total density, and medican power frequency were calculated. Differences among the EEG patterns, which were represented by F values through discriminant analysis of those 8 variables, in each level of anesthesia were significant among all concentrations except between 1% and 2% enflurane administration. The results suggest that the discriminat anlysis for the EEG parameters derived from power spectrum analysis can apply to determine the level of enflurane anesthesia.
Anesthesia
;
Anesthetics*
;
Animals
;
Electroencephalography*
;
Enflurane*
;
Inhalation
;
Rats*
;
Scalp
;
Spectrum Analysis*
3.Effect of Oliguria Within 2 Months Postoperative Period on Graft Outcome in Renal Transplantation.
Oh Sang KWON ; Young Joo KWON ; Young Gee LEE ; Gil Mann JUNG ; Nan Hee KIM ; Mi Kyoung JANG ; Yong Sub KIM ; Ja Ryong KU ; Dae Ryong CHA ; Won Yong CHO ; Heui Jung PYO ; Hyoung Kyu KIM
Korean Journal of Medicine 1998;54(1):83-89
OBJECTIVE: Graft survival rate has been improved due to newly developed immunosuppressive agents, care of recipient and operative method. However, since many risk factors are still threatening the graft survival, many studies have been underway to identify such factors, one of which has been on delayed graft function(DGF). Extending the definition of DGF to oliguria within 2 months postoperative period(POP), we began this study in order to evaluate what effects oliguria within 2 months POP have on graft survival and what are the risk factors involved. METHODS: 103 patients who have had renal transplantation performed were divided into two groups (oliguric group and non-oliguric group), based on the presence or absence of oliguria within 2 months POP. Risk factors such as the recipient factors(age, gender), donor factors(age, gender), operative factors(warm ischemia time, intraoperative urine volume), HLA typing, postoperative hypotension, postoperative hypovolemia were compared between the two groups and the impact of oliguria on graft outcome was also analysed. RESULTS: 1) 14 were Oliguric patients and 89 were nonoliguric patients. 2) One-year graft survival rate was 40% in the oliguric group and 98% in the non-oliguric group(P<0.05). 3) As the result of analyzing the risk factors, non living related donor(living non-related donor and cadaver donor) were 7(50%) in the oliguric group and 16(18%) in the non-oliguric group(P<0.05). The mean intraoperative urine volume was 442m1 in the oliguric group and 774m1 in the non-oliguric group(P<0.05). The occurrence of postoperative hypotension were 5(36%) in the oliguric group and 1(1%) in the non-oliguric group(P<0.05). Other risk factors such as the recipient fractors, donor factors, warm ischemia time, HLA typing and postoperative hypovolemia were not significantly different between the two groups. CONCLUSION: Graft survival rate in the oliguric group was lower than in the non-oliguric group. The risk factors for oliguria were non living related donor, intraoperative urine volume lower than 500m1 and postoperative hypotension. In conclusion, renal transplantation from non living related donor needs to be proceeded with caution; the maintenance of intraoperative urine volume and the prevention of postoperative hypotension are essential for better graft outcome.
Cadaver
;
Graft Survival
;
Histocompatibility Testing
;
Humans
;
Hypotension
;
Hypovolemia
;
Immunosuppressive Agents
;
Ischemia
;
Kidney Transplantation*
;
Oliguria*
;
Postoperative Period*
;
Risk Factors
;
Tissue Donors
;
Transplants*
;
Warm Ischemia