Biomedical subjects

Y Tanifuji

Publications and source records attributed to Y Tanifuji.

At least 37 records · Page 2Linked to original sources

PubMed1991

[Solubility of desflurane (I-653), sevoflurane, isoflurane, and halothane in human blood].

The blood/gas partition coefficients for the new volatile anesthetic agent desflurane (I-653), sevoflurane, isoflurane, and halothane were determined, simultaneously, in 8 human volunteers to compare the solubilities of these agents in blood. The blood/gas partition coefficient for desflurane [0.49 +/- 0.03 (mean +/- SD)] was smallest, followed by sevoflurane (0.62 +/- 0.04), isoflurane (1.27 +/- 0.06), and halothane (2.46 +/- 0.09). Differences among the anesthetic agents were significant (P less than 0.001). The results of this study confirm that among these agents the solubility of desflurane in human blood is the smallest. The results suggest that the washin and washout of desflurane will be more rapid than that of sevoflurane, isoflurane, and halothane, and the washin and washout of sevoflurane will be more rapid than that of isoflurane and halothane.

Adult↗

PubMed1990

[Is MAC effected by liver dysfunction?--Bilirubin and MAC].

If MAC is decreased in patients with liver injury, the amount of inhaled anesthetic administered to these patients could be reduced, and thereby reducing the impact of the anesthetic in such patients. The effect of jaundice in liver injury on halothane MAC was investigated in this study. After MAC for control was determined, 12 mongrel dogs received ligation of the common bile duct (CBD). MAC determination followed 1, 2, and 3 weeks after CBD ligation in 6 dogs in experiment 1. The other 6 dogs received bilirubin i.v. 1 week after CBD ligation, and MAC was determined before and after bilirubin, i.v. in experiment 2. Halothane was the only anesthetic used throughout the studies. In experiment 1, serum total bilirubin (TBil) increased to 7mg.d1-1; bilirubin did not enter the cerebro-spinal fluid (CSF); and MAC did not decrease significantly. In experiment 2, TBil increased to 21mg.dl-1; bilirubin entered the CSF; MAC significantly decreased 15% from control; and the correlation between MAC decrease and TBil increase was statistically significant (P less than 0.05). The results suggest that increase in serum bilirubin in liver injury will decrease MAC.

Anesthesia, Inhalation↗

PubMed1990

[Sudden cardiac arrest during percutaneous nephrostolithotomy (PNL) under epidural anesthesia].

There have been few major complications of percutaneous nephrostolithotomy (PNL) reported. We recently experienced cardiac arrest during PNL under epidural anesthesia. The patient was a 52 year old man weighing 64 kg who had been suffering from right renal pelvic stone for years. He was scheduled for PLN under epidural anesthesia. Analgesia was obtained to the level of Th6. The operation proceeded uneventfully for about 60 min. By this time, he suddenly complained nausea, and hypotension with bradycardia occurred. Blood pressure and pulse rate returned immediately to the normal level by IV atropine and ephedrine. But after three minutes, blood pressure and pulse rate went down again. This hypotension with bradycardia was unresponsive to epinephrine, calcium chloride and sodium bicarbonate. This was followed by asystole. Resuscitation was successful with the addition of epinephrine, calcium chloride, and sodium bicarbonate about 15 min after cardiac massage had started. The patient was, on the fifth postoperative day, with no evidence of impairment of renal, cardiac and respiratory functions but a slight impairment of neurologic function. Several possible causes for this cardiac arrest and anesthetic management of percutaneous nephrostolithotomy are discussed.

Anesthesia, Epidural↗

PubMed1990

[Effects of dopamine and dobutamine on hepatic circulation and metabolism in hemorrhagic hypotensive pigs].

Effects of dopamine and dobutamine in a dose of 5, 10 or 20 micrograms.kg-1.min-1 on hepatic blood flow and hepatic metabolism were studied in normotensive and hemorrhagic hypotensive (MAP 50mmHg) pigs during 1 MAC enflurane anesthesia. PaCO2 was maintained within a physiological range (30-35mmHg) by controlled ventilation. Portal venous blood flow and hepatic arterial blood flow were measured by ultrasonic blood flowmetry. Hepatic oxygen supply and consumption were calculated from blood flows and oxygen contents. Each dose of dopamine and dobutamine did not change significantly MAP and cardiac output in both normotensive and hypotensive pigs. In the normotensive state, dopamine increased significantly total hepatic blood flow and hepatic oxygen supply, by raising portal venous blood flow, but dobutamine did not increase them. Also in the hemorrhagic hypotensive state, dopamine increased significantly total hepatic blood flow and hepatic oxygen supply by increasing both portal venous blood flow and hepatic arterial blood flow, but dobutamine did not produce similar increase. On the other hand, there was no significant change in hepatic oxygen consumption in both normotensive and hypotensive pigs by dopamine and dobutamine administration. These results suggest that dopamine is superior to dobutamine for hepatic circulation and hepatic metabolism especially in the hemorrhagic hypotensive state.

Animals↗

PubMed1989

Effect of halothane and enflurane on hepatic blood flow and oxygen consumption in dogs.

We investigated the relative effects of 0.5, 1.0, 1.5, 2.0 MAC halothane and enflurane, and concurrent noxious stimulus on hepatic blood flow and oxygen consumption in 14 mongrel dogs randomly divided into groups of seven each. Hepatic arterial and portal venous blood flow (HABF and PVBF, respectively) were measured continuously using ultrasonic transit time flow meter. Mean arterial blood pressure (MAP), cardiac index (CI), hepatic oxygen supply, and hepatic oxygen consumption (HVO2) were measured. Halothane significantly deceased HABF, but not PVBF in a dose dependent manner. Enflurane did not affect HABF and PVBF significantly. MAP and CI decreased in both groups, with halothane producing more marked decreases than enflurane. HVO2 did not change with enflurane, but did with halothane, producing significant differences, with halothane being greater at 1.5, 2.0 MAC. A noxious stimulus only caused minor change in blood flow. The results suggest that liver blood flow and oxygen consumption are affected differently by halothane and enflurane and that halothane has a stronger tendency to cause an imbalance between liver oxygen supply and consumption than dose enflurane.

Journal Article↗

PubMed1989

Inflammatory pigmented paravenous retinochoroidal atrophy.

A 47-year-old Japanese man had a progressive degeneration of the retina and choroid along the retinal veins associated with uveitis of two years' duration. The lesion was characteristic of paravenous retinochoroidal atrophy: a contiguous atrophy of the retinal pigment epithelium and choroid of one-half to one disc diameter in size was present along most of the veins from the posterior pole to the far periphery. Fluorescein angiography showed a window defect in the retinal pigment epithelium, with hyperfluorescence representative of retinal pigment epithelium and choriocapillaris degeneration. Good visual acuity was attained after extracapsular cataract extraction for complicated cataract and vitrectomy for severe vitreous opacity had been performed in both eyes. The cause of this new inflammatory disease was unknown.

Atrophy↗

PubMed1988