Decreased cardiac output and increased plasma thromboxane have been observed during aortic cross-clamping under general anesthesia. Amelioration of these changes has been reported by preoperative administration of cyclooxygenase inhibitors, but heterogeneity in patients' intravascular volume status has confounded analysis of the drugs' effects in previous studies. We studied hemodynamic conditions in 24 volume-loaded (pulmonary capillary wedge pressure > 10 mm Hg) patients undergoing abdominal aortic aneurysm repair under general plus epidural anesthesia, after preoperative double-blind administration of either ibuprofen 800 mg (n = 12) or placebo (n = 12). The hemodynamic response to aortic cross-clamping was similar in both groups. Pulse and mean arterial pressure remained unchanged; cardiac index decreased after aortic cross-clamping from 2.4 ± 0.1 (mean ± standard error of the mean [SEMI) to 2.1 ± 0.1 1/min/m2 in the ibuprofen group and from 2.5 ± 0.1 to 2.3 ± 0.2 1/min/m2 in the placebo group (p < 0.01 versus preclamp values in both groups, multivariate analysis of variance [MANOVA]), but improved after declamping. Both left and right ventricular stroke work indexes followed a similar pattern. Plasma 6-keto prostaglandin F1α (6-k-PGF1α) increased transiently from a baseline level of 304 ± 44 to 2083 ± 698 pg/ml plasma in mixed venous blood 30 minutes after incision in the placebo group (p < 0.05), but no other significant change in plasma 6-keto prostaglandin F1α or in thromboxane B2 occurred in either group at any other time. We conclude that perioperative management that includes general-epidural anesthesia and adequate volume loading stabilizes hemodynamics and thromboxane production during aortic cross-clamping, and that ibuprofen does not confer additional benefit in this setting.
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine