A patient with gross fecal contamination and peritonitis from a ruptured sigmoid diverticulum has his midline wound left open to heal by secondary intention. Which of the following statement(s) describes this healing process?

b. A bed of granulation tissue forms over exposed subcutaneous tissue

d. The ability of a wound to form granulation tissue is dependent on the blood supply of the tissue

Open wounds, whether they be ulcers or open surgical incisions closing by secondary intention, heal with the same sequence of inflammation, matrix deposition, epithelialization, and scar maturation as in all wounds. The major difference is in the healing incisional wound, the healing process progresses in an orderly temporal sequence. In an open wound, the healing events are spatially separated. In the healing wound, a bed of granulation tissue forms over the exposed subcutaneous tissue. Granulation tissue is composed of new capillaries, proliferating fibroblasts, an immature matrix of collagen, proteoglycans, substrate adhesion molecules, and acute and chronic inflammatory cells. Granulation tissue is the cobblestone pink surface of the healthy new tissue in an open wound. The ability of an open wound to form granulation tissue is governed by the blood supply to the tissue and the relative absence of devitalized tissue and bacteria. Epithelialization is therefore enhanced by limiting bacterial growth which presumably interferes via bacterial and phagocytic cell products such as proteases, collagenases, elastases, and other enzymes.