NR 324 Adult Health ROK 3 Latest Update

1. Explain the process of wound healing by primary, secondary, and tertiary intention. Primary Intention. Primary intention healing takes place when wound margins are neatly approximated, as in a surgical incision or a paper cut. A continuum of processes is associated with primary healing. These processes include three phases. A. Initial Phase. In the initial (inflammatory) phase, the edges of the incision are first aligned and sutured (or stapled) in place. The incision area fills with blood from the cut blood vessels, blood clots form, and platelets release growth factors to begin the healing process. This forms a matrix for WBC migration. An acute inflammatory reaction occurs. B. Granulation Phase. The granulation phase is the second step. The components of granulation tissue include proliferating fibroblasts; proliferating capillary sprouts (angioblasts); various types of WBCs; exudate; and loose, semifluid, ground substance. C. Maturation Phase and Scar Contraction. The maturation phase, during which scar contraction occurs, overlaps with the granulation phase. It may begin 7 days after the injury and continue for several months or years. This is the reason abdominal surgery discharge instructions limit lifting for up to 6 weeks. Collagen fibers are further organized, and the remodeling process occurs. Fibroblasts disappear as the wound becomes stronger. Secondary Intention. Wounds that occur from trauma, ulceration, and infection have large amounts of exudate and wide, irregular wound margins with extensive tissue loss. These wounds may have edges that cannot be approximated (brought together). The inflammatory reaction may be greater than in primary healing. This results in more debris, cells, and exudate. The debris may have to be cleaned away (debrided) before healing can take place. The process of healing by secondary intention is essentially the same as healing by primary intention. The major differences are the greater defect and the gaping wound edges. Healing and granulation take place from the edges inward and from the bottom of the wound upward until the defect is filled. There is more granulation tissue, and the result is a much larger scar. Tertiary Intention. Tertiary intention (delayed primary intention) healing occurs with delayed suturing of a wound in which two layers of granulation tissue are sutured together. This occurs when a contaminated wound is left open and sutured closed after the infection is controlled. It also occurs when a primary wound becomes infected, is opened, is allowed to granulate, and is then sutured. Tertiary intention usually results in a larger and deeper scar than primary or secondary intention.