The Effects of Inhalation Anesthetic Agents on Survival in a Pig Random Skin Flap Model

In recent years a myriad of studies have been performed investigating the effects on flap survival of various pharmacologic agents. One class of agents, however, that has received relatively little attention is the inhalational anesthetics. Yet, they are widely used during reconstructive efforts using skin flaps and they possess several pharmacologic properties shown to affect flap survival. Using a dorsally based random skin flap model in 28 swine, the influence of nitrous oxide and isoflurane on skin flap survival was examined. The mean area of skin flap survival in the isoflurane, nitrous oxide, euoxemic control, and hyperoxygenated control groups was 79.4%, 29.7%, 42.0%, and 28.6%, respectively. A significant improvement in flap viability was seen only in the group using isoflurane as the anesthetic agent. Arterial blood gas content (Po2, Pco2, and HCO3), respiratory rate, acid-base balance, blood pressure, pulse, and temperature were monitored. Improved survival of the isoflurane group was independent of these parameters. These data suggest that the choice of anesthetic agent may effect random skin flap survival with isoflurane providing the greatest benefit of the agents tested in this model.