The effect of felodipine on endothelin-1 levels, peripheral vasoconstriction and flap survival during microvascular breast reconstruction

Abstract

Endothelin-1 (ET-1) may contribute to vasoconstriction and flap blood flow during microvascular surgery. Calcium antagonists have suppressed ET-1 release in some studies. The effect of 5 mg of felodipine, a vasodilating calcium antagonist, administered the evening and morning before a microvascular TRAM (transverse rectus abdominis musculocutaneous) flap breast reconstruction, on perioperative plasma ET-1 concentrations, peripheral temperature gradient (Tgrad), rectal temperature (Trect), flap skin blood flow with transcutaneous oxygen tension (ptcO2), heart rate (HR) and mean arterial pressure (MAP) was evaluated in this clinical, randomised, double blind, prospective study. Felodipine did not cause any statistically significant changes in ET-1 levels, Tgrad, Trect, Ptc O2, flap survival or pre- or intraoperative MAP. HR was significantly higher in the felodipine group before induction and at 10 min postoperatively. We conclude that in patients undergoing a microvascular TRAM flap breast reconstruction, preoperatively administered felodipine has no effect on perioperative ET-1 levels, temperature changes, or flap skin blood flow.