Effects of basic fibroblast growth factor on irradiated porcine skin flaps.

OBJECTIVE To determine the vascular and collagen effects of supplemental basic fibroblast growth factor (bFGF) in irradiated porcine skin flaps. INTERVENTION Animals were subjected to 2 fractions of 650 cGy orthovoltage radiation. Following this, the skin flaps were administered bFGF intracuticularly for 6 days before and after surgery. The animals were sacrificed 3 weeks after the start of bFGF administration. Tissues were analyzed for vascularity, collagen content, wound-breaking strength, and histopathological analysis. RESULTS The bFGF-treated flaps showed a 62% increase in vascularity compared with controls (10.4%+/-2.4% vs 6.43%+/-2.27%; P<.05). The bFGF flaps had a significantly lower collagen concentration compared with control flaps when measured by hydroxyproline content (0.0619+/-0.0211 nm/microg vs 0.0784+/-0.0150 nm/microg). Wound-breaking strength was not significantly different, although the bFGF flaps had a trend toward lower breaking strength. Histologically, the bFGF-treated flaps showed increased cellularity, fibroblasts, and extracellular mucopolysaccharides compared with controls. CONCLUSIONS This study provides evidence that supplemental bFGF can increase vascularity to skin flaps in previously irradiated porcine skin tissue. Histologically, radiation did not prevent the angiogenic effect of bFGF.