Transcutaneous electrical nerve stimulation in viability of a random skin flap in nicotine-treated rats

Background: Skin flaps are extensively used in plastic surgery, the main postoperative problems being ischemia and necrosis. Nicotine has acute vasoconstrictive properties, diminishing blood flow and increasing the risk of flap necrosis. Transcutaneous electrical nerve stimulation (TENS) was effective in reducing necrosis in random skin flaps in rats. Therefore, the authors decided to test the efficacy of TENS to reduce necrosis in the presence of nicotine. Methods: Sixteen adult male Wistar-Escola Paulista de Medicina (EPM) rats were distributed, at random, in 2 groups of 8 animals. The nicotine group (NG) received this drug subcutaneously (1.2 mg/kg/d), for 1 week before flap elevation. The nicotine plus TENS group (NTG) followed the same routine. Immediately after the operative procedure and on the next 2 postoperative days, the treatment group (NTG) was submitted to TENS during an hour under anesthesia. NG animals were sham exposed. After 7 days, the percentages of necrosis were determined. Results: The NG had a mean value of 45% and the NTG, 21% of necrosis, a difference statistically significant (P < 0.001). Conclusion: TENS was effective in the reduction of necrosis in this flap model.