[Effect of vasodilators on femoral-to-radial arterial pressure gradient after cardiopulmonary bypass].

In 57 adult patients undergoing valve replacement surgery or valve plastic surgery, pressure gradient between the femoral and radial artery was evaluated after cardiopulmonary bypass (CPB). During CPB, the rectal temperature was kept at mild or moderate hypothermia. Nitrates and prostaglandin E1 were administered in all patients during operation. Patients were divided into two groups; Group A of 31 patients who had history of hypertension and received some vasodilators up to the operation, and Group B of 27 patients who had no history of such medication. There was no difference in patient's characteristics, anesthetic time, CPB time and aortic cross clamping time between the two groups. There was a significant difference between the pre-CPB and post-CPB in hematocrit data. Systemic vascular resistance (SVR) decreased significantly from the pre-CPB level to the post-CPB level. There was no significant difference between Group A and Group B in SVR, but a higher femoral-to-radial artery pressure gradient was observed in Group A until the end of operation. Hypertension and the use of vasodilator change the tone of peripheral blood vessels and intensify femoral-to-radial artery pressure gradient after CPB.