Middle cerebral arterial blood flow velocity and hemodynamics in heart surgery

The aim of this study was to evaluate the effects of propofol, isoflurane, and sevoflurane on middle cerebral arterial blood flow velocity during open heart surgery, and the relationship between these effects and hemodynamic parameters. Fifty-two patients undergoing coronary artery bypass on cardiopulmonary bypass were divided randomly into 3 groups: the first group received 100 microg x kg(-1) x min(-1) propofol, the other groups received one minimum alveolar concentration of sevoflurane or isoflurane for anesthesia maintenance. Middle cerebral arterial blood flow velocities were measured by transcranial Doppler, and hemodynamics were measured by the thermodilution technique. Middle cerebral arterial blood flow velocities decreased significantly after administration of isoflurane and propofol, but there was no significant difference between the groups. After weaning from cardiopulmonary bypass, cerebral blood flow increased and came close to the value after induction in all groups. The pulsatility index and resistivity index increased significantly only after the propofol infusion, but there was no significant difference between the groups.