especially important to consider if used to repair defects around free anatomic margins. The cosmetic outcome is inferior to that of a FTSG as color and texture usually are not a good match. The technique of meshing the STSG further reduces cosmesis. Additionally, the donor site usually hypopigments.

34.7.1 Graft Harvest

Once the donor site is selected, it is anesthetized, cleansed, and prepared for harvesting. The wound to be grafted is measured in order to harvest the appropriate-sized donor skin. As with the FTSG, it is important to harvest extra tissue to allow for contracture. One may harvest a STSG with a dermatome or the freehand method [12]. A uniform width and depth can be achieved with the dermatome. Dermatomes are manually powered or powered by battery, electricity, gas, or air. A lubricant, such as mineral oil, is applied to the donor site to ensure easy movement of the dermatome over the donor skin. During harvesting, an assistant uses a sterile tongue depressor to apply countertraction to the area in front of the dermatome, while the surgeon applies traction behind the dermatome with his/her other hand. A slightly downward and forward motion is used to harvest the skin. Using forceps, the donor skin is removed from the dermatome as it is harvested in order to prevent damage to the graft. The donor skin is then detached by a fluid upward movement or by scissors or scalpel.

Once the graft is detached, it is placed in saline. The open donor site is dressed with gauze soaked in saline or 1:400,000 epinephrine solution to achieve hemostasis. The graft is transferred to a meshing plate with sterile saline to keep the graft moist. Attention to the orientation of the graft is important, and care should be taken to prevent rolling of the graft while it is guided slowly through the mesher in order to prevent wrinkling.

Meshing of the STSG has many purposes. First, meshing results in a graft that is larger than the size of the original tissue while still maintaining integrity. Second, the interstices created permit drainage of wound exudate and therefore help to avoid hematoma or seroma formation. Moreover, meshing decreases the time needed for complete healing and decreases morbidity. On the other hand, meshing diminishes the cosmetic appearance of the graft. There is also a higher incidence of wound contraction with meshing.

Punch grafts and pinch grafts are freehand STSG that are sometimes used to repair nonhealing ulcers [13]. Once the donor site has been anesthetized, cleansed, and prepped, the grafts are harvested with a 4-mm punch biopsy instrument (punch graft) or by scalpel or Weck knife (pinch grafts). The graft is then placed in saline-soaked gauze, and the donor site is covered with saline-soaked gauze. This method allows for several small grafts to be placed on the defect. The cosmetic result is often variable as the grafts are not of uniform thickness; however, overall take is good.

34.7.2 Graft Fixation

The three-dimensional flexibility of meshed, dermatome harvested grafts allows for ease in fitting and fixing irregular wounds with nonabsorbable superficial sutures or surgical staples. When stapling, one prong of the staple is hooked through the graft, then the other prong is placed on the skin surrounding the graft [14]. The stapler is squeezed and the staple placed. The staples should only be placed deep enough to secure the graft in place. The graft is then held in place with a pressure dressing consisting of several layers, including a nonstick petroleum jelly–impregnated gauze, nonadherent dressing, followed by a pressure and compression dressing (in the absence of arterial insufficiency). An occlusive dressing is used for the donor site, which allows for rapid healing, decreased pain, and control of acute wound exudate. The dressing on the recipient site should be changed weekly; however, those on the donor site should not be disturbed until the dressing begins to leak.

Freehand harvested grafts do not need to be sutured in place. The dressings and wound care described for the STSG from dermatome harvested grafts are sufficient to secure both the grafted and donor sites.

Summary: Composite Grafts

•Composite skin grafts are used principally to repair full-thickness skin defects in areas where cartilage must be replaced.

•Increased metabolic demands lead to higher risk of failure, and one should limit the size to less than 1.5 cm.