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ABSTRACT: In living donor liver transplantation, propofol, an intravenous anesthetic drug, has recently been used in both donors and recipients. Propofol is known to have intra- and extrahepatic metabolic pathways, but the effect of its continuous infusion during a long-term anhepatic state is yet to be determined. Recently, we successfully established a simplified pig model of the complete anhepatic state. In this state, we first evaluated hemodynamic parameters relating to the pharmacokinetics of continuously infused propofol (6 mg.kg(-1) x h(-1)). No significant changes in the concentration of hemoglobin or in hemodynamic parameters other than the heart rate were observed during the anhepatic phase when porpofol was continuously infused at the rate that maintains the state. Blood propofol concentrations in the mixed vein, artery, and portal vein were stable during the anhepatic phase. Finally, we confirmed the pharmacokinetics of continuously infused propofol using orthotropic liver transplantation in miniature pigs. The propofol concentration did not change markedly during the transplant procedure. In conclusion, the pharmacokinetics of continuously infused propofol was almost stable with and without the liver in pigs. Extrahepatic metabolism of propofol might help prevent changes in propofol concentrations.
Transplantation Proceedings 01/2006; 37(10):4567-70. · 1.00 Impact Factor
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ABSTRACT: Compared to cadaveric liver transplantation, living-related liver transplantation (LRLT) has the physiological advantage of avoiding hemodynamic changes due to the nonsystemic clamping of the inferior vena cava (IVC). However, metabolic changes in the level of blood glucose and lactate usually occur during the anhepatic phase in LRLT. For pediatric patients, intraoperative infusions have the potential to maintain immature homeostasis during LRLT. In the present study, a complete anhepatic model of baby pigs with nonsystemic clamping of IVC, which mimics the procedure of pediatric LRLT, was established using a heparin-coated tube as an internal shunt lactate Ringer solution (LR, Lactec), acetate Ringer solution (AR, VeenF), and a solution comprising acetate Ringer with 1% glucose (AR-G, Phisio140) were tested using piglets. Hemodynamic and metabolic (blood gas analysis, electrolytes, blood lactate, and glucose) changes were observed during the anhepatic phase. Although no major difference was observed in hemodynamic parameters, arterial blood gas data, or concentration of electrolytes among the three solution groups, significant progressive hyperlactatemia was observed in the LR group. Also, though severe hypoglycemia was found in the LR and AR groups, the AR-G group maintained blood glucose levels throughout the anhepatic phase. To conclude, using the simplified pig anhepatic model, we evaluated various solutions for pediatric LRLT.
Transplantation Proceedings 07/2005; 37(5):2341-6. · 1.00 Impact Factor
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ABSTRACT: The effectiveness and toxicity of many drugs depends on the dosing-time schedule, relative to the circadian rhythms of biochemical, physiological, and behavioural processes. Previous studies have found chronopharmacology of ketamine, which is a N-methyl-d-aspartate (NMDA) receptor antagonist. The in vivo contribution of the NMDA receptor epsilon1 subunit (NR2A) in this effect is unclear.
In the present study, daily variations in the hypnotic effect of ketamine were determined in wild-type mice and NMDA epsilon1 knockout (KO) mice.
The effect of ketamine had a definite daily variation in wild-type mice. No significant difference in blood concentration was observed at different dosing times (10:00 and 22:00). In NMDA receptor epsilon1 KO mice, the hypnotic effect of ketamine was weaker than in wild-type mice and there was no dependence on the time of administration. Significant pharmacokinetic differences were not observed between wild-type and KO mice.
The enhanced hypnotic effect in the active phase of the circadian cycle is likely a result of changes with the time of day in the susceptibility of the central nervous system to ketamine. Knockout of the NMDA receptor epsilon1 subunit gene markedly reduced the effect of ketamine, and eliminated the time-dependent sensitivity to ketamine.
BJA British Journal of Anaesthesia 07/2004; 92(6):859-64. · 4.24 Impact Factor
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ABSTRACT: This study aimed to clarify the difference in the effects of Ringer's acetate (AR) and Ringer's lactate (LR) administration during cardiovascular surgery with cardiopulmonary bypass. We evaluated their effects on intra and postoperative metabolism, liver functions, blood gas and hemodynamic states. Twenty patients were divided into two groups; AR group (n = 10) and LR group (n = 10). Intraoperative serum D-lactate levels in LR group were significantly higher than those in AR group from the beginning of the operation to awakening. Serum acetate levels showed no increase in both groups. The arterial ketone body ratio (AKBR) in AR group was higher than that in LR group, but the difference was not significant. Serum glutamic pyruvic transaminase (GPT) and alkaline phosphatase (ALP) levels in LR group were significantly higher than those in AR group from the induction of the anesthesia. It has been reported that acetate has a greater vasodialatory effect than lactate. However, our findings indicate no significant difference in hemodynamics between the two groups. These results suggest that AR may be more useful than LR during cardiovascular surgery with cardiopulmonary bypass.
Masui. The Japanese journal of anesthesiology 06/2000; 49(5):530-4.
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ABSTRACT: Yukiguni Yamato General Hospital (199 beds) is one of main local hospitals of Minamiuonuma area in Niigata prefecture. From June 1997, an anesthesiologist has been employed as a staff of this hospital instead of parttimers. We examined whether employment of an anesthetic staff was useful for a local hospital or not, in terms of clinical and cost advantages. There were benefits in explaining the nature of anesthesia, possible risks, operating room and pre-postoperative procedures to the patients. And there were advantages in reducing anesthetic management fee, in shortening the staying time in operating room. We conclude that there are many benefits in obtaining an anesthesiologist for a local hospital staff, but there are some drawbacks in having to work alone.
Masui. The Japanese journal of anesthesiology 07/1999; 48(6):678-81.
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ABSTRACT: From December 1989 to October 1996, 1,318 PTCAs (percutaneous transluminal coronaly angioplasty) were performed for AMI (acute myocardial infarction) or postinfarction angina in our institute. Within 7 days to 71 days after successful PTCA, five patients who had been diagnosed as cholelithiasis or gastric cancer were operated under general anesthesia. Performed operations were cholecystectomy in the first patient, subtotal gastrectomy in the second, third and fourth patients, and total gastrectomy and cholecystectomy in the fifth patient. There was no serious cardiac complication during the operations and perioperative period. PTCA is considered to have decreased cardiac complications in patients with ischemic heart disease having undergone abdominal surgery.
Masui. The Japanese journal of anesthesiology 01/1999; 47(12):1486-9.
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ABSTRACT: In order to examine the specificity of cytokine production during coronary artery bypass graft (CABG) surgery, we serially measured serum levels of monocyte chemoattractant protein-1 (MCP-1), interleukin-8 (IL-8), interleukin-6 (IL-6), interleukin-1 beta (IL-1 beta) and tumor necrosis factor (TNF), in twenty patients between 52 and 80 years of age, during surgery and 2 days afterwards. Serum MCP-1, as well as IL-8 and IL-6, increased significantly during the surgery (P < 0.05), while IL-1 beta and TNF did not. MCP-1, IL-8 and IL-6 concentrations were not different in the sera of three patients tested at three different sites, i.e., the hepatic vein, pulmonary artery and radial artery. They increased in parallel in each patient, although the actual timing of the increase relative to the surgical step varied among individuals. In complicated patients, MCP-1, IL-8 and IL-6 showed higher peaks and persisted longer than in patients without complications. The universal and simultaneous appearance of MCP-1, IL-8 and IL-6 could indicate that these three cytokines may be stimulated by a yet undiscovered stimulus (or stimuli) which occurs systemically despite the independent pathways of production.
European cytokine network 03/1997; 8(1):61-6. · 1.73 Impact Factor
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ABSTRACT: We report the usefulness of monitoring hepatic venous saturation (ShVO2) during open heart surgery for a patient with severe liver dysfunction. The patient was a 55-year-old man who had been suffering from acute aortic regurgitation due to bacterial endocarditis. Indocyanine green retention test at 15 min was 55%. Serum GOT, GPT and T bilirubin were 56 U.l-1, 35 U.l-1 and 1.5 mg.dl-1 respectively. Aortic valve replacement was scheduled in spite of severe liver dysfunction because amelioration of congestive heart failure after the operation was expected to improve liver dysfunction to the previous chronic state. Anesthesia was induced and maintained by intermittent administration of diazepam and low dose of fentanyl with 100% oxygen. After induction, we inserted a balloon tipped pulmonary catheter with ultra-red beam into hepatic vein by fluoroscopy guidance and monitored ShVO2 as an index of hepatic oxygen supply/demand balance. During re-insertion of a thoracic catheter, we could detect the continued decrease in hepatic vein saturation even after the improvement of systemic circulatory state. Postoperatively, liver function became slightly worse for a short period and improved thereafter. These results suggest that ShVO2 monitoring is clinically useful in detecting hepatic oxygen supply/demand imbalance which circulatory monitoring could not uncover during open heart surgery.
Masui. The Japanese journal of anesthesiology 08/1995; 44(7):1025-8.
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Intensive Care Medicine 02/1995; 21(1):96-7. · 5.40 Impact Factor
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ABSTRACT: To evaluate the effectiveness of low dose dibutylic cyclic AMP (DBcAMP) during coronary artery bypass graft surgery, we compared circulatory and endocrine-metabolic parameters among the three different doses: (1) DBcAMP 10 microg.kg-1.min-1 (A-10 group), (2) DBcAMP 20 microg.kg-1.min-1 (A-20 group), and (3) control (A-0 group). In the A-10 group, perfusion pressure was significantly higher than in the A-0 group at the point of maximum cooling and at the start of warming during cardiopulmonary bypass (CPB), while peripheral vascular resistance was significantly lower than in the A-0 group at the closing of CPB. On the contrary, in the A-20 group, perfusion pressure was significantly lower than in the A-0 group at the point of maximum cooling and the start of warming during CPB, while peripheral vascular resistance was significantly lower than in the A-0 group at the start of warming and the closing of CPB. Among these groups, the hourly urine volume during CPB was significantly largest in A-10 group. Endocrine-metabolic parameters showed no statistic difference among these groups. These results suggest that the administration of DBcAMP 10 microg.kg-1.min-1 during CPB might improve the cardiac performance and maintain the tissue perfusion without the endocrine-metabolic deterioration.
Masui. The Japanese journal of anesthesiology 05/1994; 43(4):504-10.
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Anesthesia & Analgesia 01/1993; 75(6):1036-7. · 3.29 Impact Factor
