Unexpected vascular response to epinephrine in port wine stains.

Success of argon laser therapy as a therapeutic modality for port wine stains has been correlated with the degree of vascular congestion within the lesions. Epinephrine causes vasoconstriction and erythrocyte stasis within normally innervated vessels. We tested the hypothesis that subcutaneous injection of epinephrine would cause vasoconstriction, altered hemodynamics, and increased red cell mass in port wine stains and thus allow more directed and less nonspecific damage and a better cosmetic result. Two clinically similar and adjacent areas within port wine stains were biopsied from 10 patients following subcutaneous injection of either Xylocaine or Xylocaine with epinephrine. Erythrocytes within vessels of the superficial cutaneous vascular plexus were increased in areas pretreated with Xylocaine plus epinephrine (55.3 versus 45.9 percent; p less than 0.09). This increase was seen in 9 of 10 patients studied (p less than 0.05). Epinephrine appears to increase erythrocytes within ectatic vessels of port wine stains and thus would likely improve laser energy absorption and cosmetic results.