[Anesthetic management in surgery of thoracic aortic aneurysms--a report of eleven cases].

Anesthetic management of patients with thoracic aneurysm is discussed. During a period of two years, 11 cases were observed; 7 cases of dissecting aneurysm and 4 cases of true aneurysm. Dissecting aneurysms were of DeBakey's type 1 in 5 cases and of DeBakey's type 2 in 2 cases. Four cases had hypertension. As many of these patients often have hypertension, it is important not to change the circulatory dynamics during induction of anesthesia. We employed high dose fentanyl in 9 cases and used nitroglycerin or nitroprusside to control systolic blood pressure at about 100-120 mmHg. Massive bleeding can occur during intraoperative period and it is important to secure a sufficient number of intravenous routes to protect the central nervous system during cardio-pulmonary bypass.

[Effects of prostaglandin E1 and dibutyryl cyclic AMP on hemodynamics after cardiopulmonary bypass in valve replacement surgery].

In view of vasodilating action of prostaglandin E1 (PGE1) and dibutyryl cyclic AMP (DBcAMP) we investigated the effect of each agent on hemodynamics after weaning from cardiopulmonary bypass (CPB) comparing with the effect in control group. PGE1 and DBcAMP were administered to patients who underwent valve replacement surgery with continuous low dose infusion at an average rate of 0.026 micrograms.kg-1.min-1 and 7.25 micrograms.kg-1.min-1 respectively. Following result was obtained. In PGE1 administered group, a significant reduction in pulmonary vascular resistance (PVR) and a significant decrease in mean arterial pressure (MAP) were observed during CBP, while there were no significant differences in other parameters, such as platelet counts, differences between core and peripheral temperature (delta T), urine output, systemic vascular resistance (SVR), cardiac index (CI), right-to-left shunt (Qs/Qt), oxygen delivery (DO2) and oxygen consumption (VO2). However, CI and platelet counts tended to increase but delta T and SVR tended to decrease. In DBcAMP administered group, there were no significant differences in all parameters compared with those of control group, showing a tendency of less improvement in hemodynamics than in PGE1 group. We have shown that the use of PGE1 rather than DBcAMP as vasodilator agent seems advantageous during open-heart surgery in patients especially with severe pulmonary hypertension, but it tends to cause severe hypotension during CPB.