Prolonged perivascular use of verapamil or lidocaine decreases skin flap necrosis

During this experiment the authors investigated whether prolonged local use of verapamil or lidocaine prevents vasoconstriction and establishes better blood supply to the rat epigastric skin flap, hence reducing the necrosis that occurs otherwise. Abdominal wall skin flaps of 45 Sprague-Dawley rats, based on a single pedicle of the femoral vessels, were elevated. A subcuta neous pocket for the microport valve was created, and the adjacent catheter tip was sewn next to the femoral vessels. In the control and the two treat ment groups, 0.5 ml saline or vasodilator solution respectively was injecte d through the microport every 12 hours for 5 days. On postoperative day 5 t here was no statistical difference between the flap surfaces in all groups. The area of flap necrosis was significantly lower in the verapamil- (p = 0 .001) and the lidocaine-treated (p = 0.012) groups vs. the control group as determined by analysis of variance with Bonferroni's post hoc test, In con clusion, topical application of verapamil and lidocaine solutions for 5 pos toperative days decreased flap marginal necrosis significantly. Prolonged i njection of vasodilators in the vicinity of the vascular pedicle prevents v asospasm and improves blood supply to the flap.