Technical Guide Technical Guide WHAT YOU NEED TO KNOW ABOUT SKIN GRAFTS AND DONOR SITE WOUNDS Pauline Beldon is Tissue Viability Nurse Consultant, Epsom and St Helier University Hospitals NHS Trust, Surrey Skin grafting is used for extensive wounds that are diffi cult to suture or for wounds that will produce prominent scars that could cause physical or psychological problems for the patient. Grafting involves the creation of another wound at the donor site that will also need nursing attention. In this article the different types of grafting procedures are described and guidance is given on the care of the resulting wounds. The skin is a vital organ with are likely to cause physical or Classifi cation of skin grafts several major functions: psychological problems through Skin grafts may be classifi ed as protection, sensation, scarring particularly in prominent partial or full-thickness grafts, thermoregulation, excretion, places (Beldon, 2003). Skin depending on how much of absorption, metabolism and grafting is not a new procedure the dermis is harvested by the non-verbal communication and has been performed for surgeon (Figure 3). (Timmons, 2006). Any breach thousands of years. Accounts in skin integrity may lead of skin grafting have been found A split-skin or partial-dermal to the disruption of one or in India from about 2,500 years skin graft involves excision more functions as well as ago (Davis, 1941). of the epidermis and part of pain, discomfort and possible the dermis, but leaves behind infection. Some wounds may Defi nition of a skin graft suffi cient reticular (deep) dermis be sutured (primary intention A skin graft is a section of in the wound bed to enable the healing) whereas open wounds epidermis and dermis which has skin to regenerate itself. The may heal by secondary been completely separated from most common donor site areas intention, which is a slower its blood supply in one part of for split-skin grafts include the process. The longer a wound the body, the donor site, before thigh, buttock, back, upper arm, exists, the greater the potential being transplanted to another forearm and abdominal wall for infection as it will require area of the body, its recipient (Coull, 1991). regular dressing changes over site (Grabb and Smith, 1991). a period of time; a procedure A full-thickness graft consists that will always carry a risk of The type of skin graft most of the epidermis and the full- potential infection. commonly used is the autograft, thickness of the dermis. Since when the donor and recipient none of the reticular dermis Skin grafting will cover a of the skin graft are the same remains to allow spontaneous wound, excelerate healing and person, for example when a regeneration of skin, the minimise scarring and should patient has a skin graft taken wound must be directly closed be considered when wounds from their thigh (Figure 1) and to heal by primary intention. are extensive, unsuitable applied to a wound on their Consequently, the surgeon for closure by suturing, or lower leg (Figure 2). must select a donor site where 38 Wound Essentials • Volume 2 • 2007 Wound Essentials • Volume 2 • 2007 149 149-55skingraft.indd 3 3/6/07 11:29:54 pm Technical Guide Technical Guide a small area of skin may be excised and the wound sutured to leave minimal scarring. Common donor site areas for full-thickness skin grafts include the pre- and post-auricular (ear), supraclavicular and antecubital (inner elbow) areas, the upper eyelid, scalp, groin and areola ( Figure 4 ; Nanchahal, 1999). Full-thickness skin grafts do not contract as much as split-skin grafts, so are used to cover exposed areas of the body, usually the face or neck. Figure 1. A split-skin graft taken from an anterior thigh donor site. Meshed skin grafts If a skin graft is passed through a meshing device made from two metal rollers, it will insert multiple fenestrations (holes) into the skin graft, allowing the surface area to be dramatically increased. A graft which originally measured 5x5cm, may be doubled or tripled in size. This avoids the need to harvest large areas of skin and spares the patient a large donor site wound. Dermatome Figure 2. Anterior tibia recipient site. Skin graft Upper eyelid Post-auricular skin Pre-auricular skin Nasolabial groove Forceps Supraclavicular skin Figure 4. Common donor site areas for full-thickness skin grafts. Figure 3. The harvesting of a skin graft. 150 Wound Essentials • Volume 2 • 2007 149-55skingraft.indd 4 3/6/07 11:29:59 pm Technical Guide Technical Guide Meshed skin grafts (Figure 5) are graft against the wound bed. A since the amount of nutrients particularly useful if the wound tie-over pack may be used to able to reach the graft by is expected to bleed or produce secure small grafts, especially plasmatic imbibition is inversely copious amounts of serous to the head or neck area, or proportional to the thickness of fluid. The meshed graft allows grafts placed into deep defects, the graft. fluid to pass through and into e.g. an axilla wound. Sutures the dressing and this prevents are placed around the edge of Innosculation occurs when the development of haematoma the graft and the ends drawn severed blood vessels in the or seroma. The fenestrated together over a pack of foam skin graft anastomose or unite area rapidly epithelialises to or sterile wool to ensure even with the severed ends of vessels provide complete skin cover. pressure is applied by the pack of approximately the same Unfortunately, meshed skin which thus secures the skin diameter in the wound bed. grafts are not suitable for all graft to the site. Staples and This occurs between 24–72 areas of the body, since the skin clips have also been used as a hours after application of the retains a meshed appearance rapid means of securing a graft graft. The fibrin network acts and would be unsightly on the in position. as a supportive frame along hands, neck or face (McGregor which endothelial buds from and McGregor, 1995) (Figure 6). Adherence of the skin graft blood vessels in the wound bed to the wound bed grow to meet the blood vessels Application of the skin graft Soon after application of the in the skin graft. Blood flows to the recipient site skin graft, a fibrin network through the anastomoses into For a skin graft to adhere is produced which acts as a the graft vessels on day 3–4 successfully to the wound biological ‘glue’ and adheres and is sluggish until day 5–6 bed, two conditions must be the graft to the wound bed. (Converse et al, 1975). Once satisfied. First, the wound bed This network is then infiltrated this is established the skin graft should be clean and free from by fibroblasts, leucocytes gradually takes on colour and necrotic or sloughy tissue which and phagocyte cells from the becomes red-purple. The skin would be heavily colonised wound bed, and is converted graft begins to develop its own with bacteria. Ideally, no bone into a fibrous tissue attachment system of blood vessels (Pope, or tendon should be exposed, between the skin graft and the 1988) and lymphatic vessels since skin grafts will not adhere wound bed. (Swaim, 1990). to these structures. Simultaneously, serous fluid As the graft continues to mature If the application of the skin containing erythrocytes in its new site, it regains partial graft to the wound is delayed, (red blood cells) and sensation from the sensory usually because of an infected polymorphonucleocytes (white nerves of the wound bed. Split- wound bed, the skin graft may cells), accumulates between skin grafts are innervated more be stored for up to seven days the skin graft and the wound quickly than full-thickness skin at 4°C after being wrapped in bed, leaked from the smallest grafts, but not as completely. saline-soaked gauze. Delayed veins (venules) in the wound This is thought to be due to skin graft application is usually bed. There are severed vessels the thickness of the skin graft performed by an experienced within the skin graft which (Branham and Thomas, 1990). nurse within a hospital setting. dilate and capillary action Scar contracture happens draws this serous fluid into gradually over the following Second, it must be held in them to provide nutrition for 6–12 months, and the thicker close proximity to the wound the graft tissues. This process the graft, the less contracture bed and immobilised. This can is known as plasmatic (serous) occurs (Branham and Thomas, be achieved by suturing the imbibition. The graft has a white 1990). This is another reason for graft in place, then using a firm appearance at this time as there using thick or full-dermal skin dressing to ensure that shearing are few erythrocytes present. grafts on the face as scarring does not occur, positioning the Thinner skin grafts fare better can be minimised. Wound Essentials • Volume 2 • 2007 151 149-55skingraft.indd 5 3/6/07 11:29:59 pm Technical Guide Technical Guide First inspection of the graft The first post-operative inspection of the skin graft is usually performed between 2–5 days (Young and Fowler, 1998). The timing of the first inspection is dependent on the wound site, the thickness of the skin graft, how the skin graft has been immobilised, the age of the Figure 5. Dermal meshed graft. patient and the existence of any underlying medical conditions which could delay healing. The first inspection may take place in hospital, a clinic or in the community, provided the doctor or nurse has the necessary expertise to assess the graft’s adherence and determine further management of the wound.