Biomedical subjects
Publications and source records attributed to H Yuasa.
Mucocele of the appendix is rare and mainly found incidentally at surgery or autopsy. Clinically, this tumor is known to cause pseudomyxoma peritonei or intussusception in adults. We present a case of adult intussusception with a leading mass of appendiceal mucocele. Computed tomography was useful in resolving the nature of the leading mass.
BACKGROUND: The edema of grafted lungs during the early postoperative period is one of the serious complications of single lung transplantation for primary pulmonary hypertension. METHODS: The effectiveness of inhaled nitric oxide in single lung transplantation for primary pulmonary hypertension during the early postoperative period was evaluated with the use of rats with monocrotaline-induced pulmonary hypertension. In the inhaled nitric oxide group, rats were given 60 parts par million of nitric oxide for 24 hours just after left lung transplantation; in the no inhaled nitric oxide group, rats were kept without nitric oxide inhalation; in the control group, normal rats received left isografts. RESULTS: Three hours after transplantation, the mean pulmonary artery pressure of the no inhaled nitric oxide group (28.0 +/- 4.6) was significantly higher than that of the control group (23.3 +/- 0.9, p < 0.05) and the inhaled nitric oxide group (22.7 +/- 1.7, p < 0.05). On the first postoperative day, the mean left-to-right pulmonary blood flow ratio in the inhaled nitric oxide group was 0.34 +/- 0.03; it showed no significant difference to those of the other two groups, whereas that of the no inhaled nitric oxide group (0.42 +/- 0.14) was significantly elevated compared with that of the control group (0.14 +/- 0.03, p < 0.05). Histopathologically, the edema of the grafted lungs 24 hours after operation in the inhaled nitric oxide group was less severe than that in the no inhaled nitric oxide group. CONCLUSIONS: The postoperative use of inhaled nitric oxide is effective to reduce the pulmonary edema of the grafts in single lung transplantation for pulmonary hypertension by reducing acute pulmonary blood flow shift toward grafts after transplantation.
Patients with aortic arch aneurysms underwent surgery using a selective cerebral perfusion (SCP) method. For this purpose, a protocol for SCP was established on the basis of an animal experimental study. Our SCP procedure is performed at a perfusion rate of 6 ml/kg/min with the patient under deep hypothermia at 20 degrees C. The subject group in the current study included 36 patients, 28 men and eight women, ranging in age from 23 to 84 years (mean, 61). There were five operative deaths (13.9%). The mean cardiopulmonary bypass time was 288 minutes, and the mean aortic clamp time was 135 minutes. Mean SCP time was 89 minutes, exceeding 90 minutes in 17 cases. The mean blood pressure during SCP was 43 mmHg and oxygen saturation rate in the internal jugular vein was at least 90%. There was no definite production of lactate in the brain. Cerebral disorders considered to have been caused by SCP occurred in only two cases. It appears that cerebral metabolism can be maintained safely, and that our SCP method is useful during surgery for aortic arch aneurysms.
The effect of nafamostat mesilate (FUT-175) on platelet membrane glycoproteins and the coagulofibrinolytic system were analyzed. Twenty-five patients undergoing aorto-coronary bypass surgery were randomly distributed into an FUT treated group and a control group. In the control group, anticoagulation was achieved with sodium heparin (3 mg/kg) immediately before cardiopulmonary bypass (CPB). In the FUT treated group, in addition to the usual treatment with heparin, FUT-175 was infused continuously at a rate of 2 mg/kg/hr. In the control group, alpha 2 plasmin inhibitor/plasmin complex (PIC) and fibrinogen/fibrin degradation products (FDP) D-dimer increased significantly during CPB, reaching 6.1 +/- 5.1 micrograms/ml and 576 +/- 200 ng/ml, respectively, at 60 min of CPB. PIC and FDP D-dimer remained significantly lower in the FUT treated group than in the control group. GPIb on platelets decreased significantly in both groups, but remained higher in the FUT treated group (81 +/- 5% vs. 56 +/- 21% at 60 min of CPB, P < 0.01). There were no significant changes in GPIIb/IIIa on platelets throughout the procedure in either group. Blood loss after CPB was significantly lower in the FUT treated group than in the control group (778 +/- 277 ml vs. 1,342 +/- 426 ml, P < 0.01). The authors conclude that FUT-175 improves hemostasis after CPB, not only by inhibiting fibrinolysis, but also by preserving platelet GPIb during CPB.
Changes in platelet membrane glycoproteins (GPIb, GPIIb/IIIa, and GMP-140) were evaluated using flow cytometry after binding with monoclonal antibodies in 22 adult patients undergoing cardiopulmonary bypass (CPB) surgery. The amount of GPIb on platelets decreased significantly during CPB, reaching a minimum level of 64 +/- 26% of the pre CPB value at 120 min of CPB. There was no significant change in the amount of GPIIb/IIIa on platelets. In accordance with these changes, ristocetin induced agglutination decreased to 56.7 +/- 16.2% of the pre CPB value during CPB. However, there were no significant changes in ADP and collagen induced aggregation throughout the procedure. The number of the activated platelets expressing GMP-140 on their surfaces increased significantly during CPB. There was an upper limit to the amount of GMP-140 expression on each platelet in the circulating blood, suggesting that excessively activated platelets are removed from the circulation. The authors conclude that CPB reduces the amount of GPIb on platelets, which results in platelet dysfunction. In addition, removal of excessively activated platelets from the circulation may lead to thrombocytopenia after CPB.