Steroids impair wound healing by:
A. Decreasing angiogenesis and macrophage migrationThe major effect of steroids is to inhibit the inflammatory phase of wound healing (angiogenesis, neutrophil and macrophage migration, and fibroblast proliferation) and the release of lysosomal enzymes. The stronger the anti-inflammatory effect of the steroid compound used, the greater the inhibitory effect on wound healing. Steroids used after the first 3 to 4 days postinjury do not affect wound healing as severely as when they are used in the immediate postoperative period. Therefore if possible, their use should be delayed or, alternatively, forms with lesser anti-inflammatory effects should be administered.
In addition to their effect on collagen synthesis, steroids also inhibit epithelialization and contraction and contribute to increased rates of wound infection, regardless of the time of administration. Steroid-delayed healing of cutaneous wounds can be stimulated to epithelialize by topical application of vitamin A. Collagen synthesis of steroid-treated wounds also can be stimulated by vitamin A.