Changes in the blood flow and prevention of vasospasm of the femoral artery by topical application of lidocaine in rats.

Free-tissue transfer with anastomosis has become an important microsurgical technique. Sometimes vasospasm occurs after anastomosis. We examined the changes in blood flow and the effect on the treatment of vasospasm of the femoral artery of rats. The rat models of vasospasm were generated by topical application of epinephrine. We topically applied 2% lidocaine as a single dose (0.2 mL) and a continuous infusion (1.0 mL/h). Our results suggest that although the effect lasts for a short period, a single application of 2% lidocaine has a rapid effect and is effective for treating a sudden manifestation of vasospasm. In contrast, continuous topical application may be more effective for maintaining the blood flow and preventing vasospasm. Therefore we believe that persistent vasospasm should first be treated with several topical applications of lidocaine; if this helps improve the condition, continuous topical application can be subsequently used as a preventive measure.