A microangiographic study of hematoma-associated flap necrosis and salvage with isoxsuprine.

Rat dorsal skin flaps predictably underwent full-thickness necrosis by 48 hours when hematoma had been placed beneath the flap. Microangiographic studies demonstrated failure of filling of the distal vasculature of these flaps. This was in marked contrast to the complete reestablishment of circulation in control flaps, overlying equal volumes of serum. The circulation of failing flaps overlying hematoma was restored with isoxsuprine given parenterally 1 hour preoperatively and every 4 hours for 24 hours postoperatively. This pharmacologic regimen gave consistent reestablishment of flap perfusion and flap survival. The toxic component of hematoma acts on the circulation to a skin flap. This may be at the same level of the vasculature as the vasodilating action of isoxsuprine.