Hemodynamic Status Following Regional and General Anesthesia for Carotid Endarterectomy

Abstract

We prospectively studied 23 patients undergoing carotid endarterectomy under regional (n = 13) or general (n = 10) anesthesia to determine the hemodynamic basis of increased frequency in the need for postoperative vasopressor support when regional anesthesia was used. Anesthesia and postoperative care were conducted without reference to hemodynamic data from pulmonary artery catheterization. Although mean arterial pressure was similar in the two groups postoperatively, 11 of the 13 patients undergoing regional anesthesia and 3 of the 10 patients undergoing general anesthesia required phenylephrine postoperatively. No patient required therapy postoperatively to reduce a systolic pressure exceeding 160 mm Hg. Mean arterial pressure remained below the preoperative baseline value in both groups (p < 0.05 with general anesthesia; p = 0.06 with regional anesthesia) during follow-up. In the general anesthesia group, systemic vascular resistance declined significantly below baseline (p < 0.05) following the operation, accompanied by a decline in mean arterial pressure (p < 0.05) and a higher cardiac output. Intraoperative fluid requirements were greater during general anesthesia than during regional anesthesia (p < 0.01). Pulmonary artery occlusion pressure was lower postoperatively than at baseline in both groups (p < 0.05). Pulmonary artery occlusion pressure was higher in the general anesthesia group despite the greater use of phenylephrine in the regional anesthesia group.