The inflammatory phase of wound healing typically begins 10-15 minutes after the initial insult and end of hemostasis.  Under ideal circumstances, and assuming proper progression through the phases of healing, this phase last 2-3 days.  Ultimately the purpose of this phase is to establish a clean wound bed and set up the next phase of wound healing.  Unfortunately the inflammatory phases been identified as the most common sticking point in the wound healing cascade.  By convention chronic wounds are felt to be “stuck” in the inflammatory phase, and there are studies that add validity to that argument.

In order to establish a clean bed, the body responds by increasing local capillary permeability,thereby causing local vasodilatation.  This process leads to the classic signs of inflammation calor, dolor, rubor, tumor, or more simply stated redness, swelling, and increased exudate.  This process is mediated through the elaboration of complement histamine and prostaglandins.

The inflammatory phase is broken up into early and late phase.  Each phase having a different predominant cellular player. In the early phase of inflammation the neutrophil is the predominant cellular mediator. Through oxidative killing and release of intracellular enzymes, nonviable proteins and bacterium are cleared from the wound bed.  In the late phase, mediated by macrophage, phagocytosis of early phase byproducts and elaboration of collagenase and elastases further cleans the wound bed.  The effects of the last stasis and collagenases are tempered by inhibitors of matrix metalloprotease or TIMPs. Due to the multitude of both cellular and chemical processes occurring in this phase there are multiple points in which inflammation can stall leading to a failed wound. The wound bed of a chronically stalled, inflamed wound has high levels of inflammatory cytokines, high protease activity, degraded and dysfunctional extracellular matrix with associated low mitogenic activity (1).

With the understanding of the complex chemical and cellular nature of the nonhealing wound treatments including dressings, topical agents, and management of comorbidities help target and correct some of the factors leading to uncontrolled inflammation.

Falanga V. The Chronic Wound: Impaired Healing and Solutions in the Context of Wound Bed Preparation.  Blood Cells and Diseases, 2004;32:88-94