Article #3 CE Partial-Thickness Skin Grafting for …...defect created can reepithelialize within 3 weeks.1 Therefore, the amount of donor skin available for par-tial-thickness grafting

L arge thermal skin wounds involvinggreater than 15% to 20% of the total bodysurface area in dogs present multiple

medical and surgical treatment challenges.These skin injuries most commonly result fromaccidental or malicious thermal burns, some-times involving a chemical accelerant. Dogswith these injuries have a wide variety of clinicalpresentations, from seemingly unaffected tosevere shock. Those severely affected requireaggressive stabilization and medical manage-ment. Concomitant medical problems that canresult from loss of large areas of skin includeanemia, neutropenia, hypoproteinemia, dehy-dration, electrolyte imbalances, pain, and weightloss. Repair of the wound prevents loss of redand white blood cells, blood and tissue proteins,body fluid, and electrolytes through the wound.

Some large skin wounds may not be amen-able to repair by full-thicknessreconstruction techniques.Techniques such as skinstretching, expansion andadvancement, tension-relieving

Partial-Thickness Skin Grafting for Large Thermal Skin Wounds in DogsCarlos L. Aragon, DVMStephanie E. Harvey, DVMSheila W. Allen, DVM, MS, DACVSM. A. McCrackin Stevenson, DVM, PhD, DACVS University of Georgia

Article #3

ABSTRACT:

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An optimal clinical outcome for large, full-thickness thermal skin wounds in dogs is pred-icated on aggressive preoperative wound management, assessment and treatment ofconcurrent medical problems, careful surgical planning and execution, and intensive post-operative care. Skin stretching, expanding and advancing techniques, skin flaps, omentalgrafts, and full-thickness skin grafts have been described for use alone or in combinationfor managing large skin wounds. Partial-thickness skin grafting may be a feasible surgicaloption when these familiar full-thickness techniques are not practical because of the sizeand location of the wound(s).This article describes the indications, advantages, disadvan-tages, and technical aspects of partial-thickness skin grafting and provides case-basedexamples of its application in dogs.

primary closure, and skin flaps may not be pos-sible because of insufficient adjacent skin. Freefull-thickness skin grafting and microvascularfree grafting may not be practical if the size ofthe defect exceeds what can be covered by theamount of distant donor skin available for full-thickness grafting. The size of the wound mayimpair wound contraction, and the locationmay predispose the animal to a function-limit-ing wound contracture if healing only by secondintention is allowed (Figure 1). This articledescribes the use of partial-thickness skin graft-ing in dogs with large thermal skin wounds andreviews the advantages, disadvantages, indica-tions, and technical considerations of this surgi-cal treatment option.

INITIAL WOUND MANAGEMENTAND ASSESSMENT FOR SURGICALTREATMENT

Dogs with large thermal skin wounds shouldfirst be treated for life-threatening complica-tions, if present, such as shock, smoke inhala-tion, and hemorrhage. The initial goal of wound

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management is to establish a healthy bed of granulationtissue free of necrotic debris and infection.1 Historically,wound debridement involves serial changes of three-layer bandages containing an adherent contact layer topromote granulation tissue.

Once granulation tissue is present, occlusive or semi-occlusive dressings can be used to promote epithelializa-tion, dermal healing, reduction in perceived pain, bettercosmetic results, ease of application, and reduction in thenumber of bandage changes.1 An important factor in theenhancement of healing open wounds is the compositionof the bandage material used. A study evaluating theeffects of equine amnion, a biosynthetic hydrogel dress-ing, transparent polyethylene sheeting, and a semiocclu-sive rayon–polyethylene nonadherent dressing on open-wound healing in dogs concluded that the meanpercentage of wound contraction and total wound healedof the amnion-bandaged wounds was greater than thatfor wounds bandaged with the other dressings.2,3

Modern advancements in wound management haveproduced a multitude of medications that stimulatewound healing, dressings that enhance healing, and skinprotectants to assist in wound protection. Release ofinterleukin-1 and tumor necrosis factor by macrophagescan be stimulated by products such as acemannan.Together, these cytokines stimulate and enhance fibro-blast proliferation, neovascularization, collagen deposi-tion, and epidermal motility and growth.3,4 Once thewound is sufficiently covered in healthy granulation tis-sue, definitive surgical therapy can be initiated.

The location and size of the wound should be consid-ered when selecting an appropriate method of surgical

closure. The location of the wound can determinewhether healing by second intention will be deleteriousto adjacent joints or body orifices, whether neighboringor distant donor tissue for a skin flap is available, orwhether recipient vessels are available for a microvascu-lar free-transfer flap. The size of the wound will deter-mine whether secondary closure or full-thickness graft-ing is feasible. The donor sites for full-thickness graftsmust be surgically closed, limiting the size of the recipi-ent site that can be covered. The donor sites for thin andmedium partial-thickness grafts are partial-thicknesswounds and need not be closed. The partial-thicknessdefect created can reepithelialize within 3 weeks.1

Therefore, the amount of donor skin available for par-tial-thickness grafting greatly exceeds that for full-thickness grafting. Both full- and partial-thicknessgrafts can be meshed to allow expansion for coveringlarge areas.

The cost of medical and surgical care associated withmanagement of large thermal skin wounds is very high,even without complications. Veterinary clinicians musteducate clients thoroughly regarding staged medical andsurgical management.

INDICATIONS, ADVANTAGES,AND DISADVANTAGES

Partial-thickness skin grafts have a variety of advan-tages and disadvantages compared with other forms ofwound closure. Careful consideration of each is impor-tant before managing every case. The primary indicationand advantage of partial-thickness skin grafts in dogs isin the reconstruction of large full-thickness woundswithout sacrificing full-thickness skin from donor sites.Donor sites heal as partial-thickness wounds and havethe advantage of minimal tissue injury because thewound is made under aseptic conditions with minimaltrauma.1 Partial-thickness skin grafts have also beenshown to survive more readily than full-thickness skingrafts because of the denser capillary network in themore superficial dermal layers, which more readilyallows capillary linkup.5,6 This may explain the higherpercentage of viability of partial-thickness skin graftsthan full-thickness skin grafts in early studies.5,7 Al-though subsequent studies showed that full-thicknessgrafts had a higher percentage of viability than previ-ously reported, the difference in viability between par-tial- and full-thickness grafts was not statistically signif-icant.7,8 A previous comparison study by McKeever andBraden9 of meshed, thin partial-thickness grafts (0.063

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Partial-Thickness Skin Grafting for Large Thermal Skin Wounds in Dogs202 CE

Figure 1. Caudal to cranial view of a function-limitingwound contracture along the dorsum of a dog presented6 months after the initial injury.

cm); meshed, medium partial-thickness grafts (0.127cm); and meshed, full-thickness grafts in dogs suggestedthat thin partial-thickness grafts had the highest sur-vival rate (89%), with full-thickness grafts (58%) andmedium-thickness grafts (47%) having lower successrates.9 Meshing both a partial- and full-thickness skingraft decreases graft contracture by increasing the num-ber of edges from which epithelialization can occur.Additional advantages of meshed skin grafts include thereconstruction of irregular surfaces (concave and convex)and application in a graft bed with exudate (blood orserum). Furthermore, meshed partial-thickness skingrafts possess the characteristics of rapid donor sitereepithelialization and multiple harvests of partial-thickness skin from areas of thick skin.10

Disadvantages of partial-thickness skin grafts includetechnical difficulty while harvesting, initial low durabilityof partial-thickness skin that is susceptible to trauma,sparse or absent hair growth on both the grafted anddonor sites, and a scaly appearance resulting from thelack of sebaceous glands.6,9,10 Partial-thickness skin grafts

also require the use of specialized and expensive equip-ment and additional training.10 Furthermore, the expenseand time associated with intense postoperative care canbe expensive and time-consuming. Despite the difficultyof harvesting, it has been reported to become easier withpractice.11 Our experience supports the use of partial-thickness skin grafting in dogs with large thermal skinwounds that are irreparable by traditional methods.

In summary, partial-thickness skin grafting can beuseful when applied in managing large thermal skinwounds in dogs. Partial-thickness skin grafting wouldmost likely be performed at a veterinary medical schoolor a highly equipped surgical specialty practice becauseof associated intense postoperative care as well as therequired expensive equipment and training for its use.This surgical option is chosen based on the size andlocation of the wound(s), availability of the necessaryequipment, experience of the surgeon, and availability ofpersonnel to provide postoperative care. Furthermore,the primary advantage of partial-thickness skin grafting

is that the donor sites do not have to be surgicallyapposed and are allowed to heal by reepithelialization.This advantage enables more versatility in selectingdonor site locations when limited donor sites are pres-ent, an obvious advantage over full-thickness skin graft-ing. Partial-thickness skin grafting should be consideredwhen other forms of wound closure are not practical orachievable as a sole means of therapy.

SURGICAL TECHNIQUE FOR MESHED,PARTIAL-THICKNESS SKIN GRAFTS

Allowing a bed of granulation tissue to form over thewound before the surgical application of a partial-thicknessskin graft is critical for graft survival.1,5–7,10,12 Granulationtissue fills in wound space, functions as a protective barrier,and provides nourishment to applied skin grafts.12 Healthygranulation tissue does not bleed excessively and is flat, red,and free of a surface film of sloughing collagen.10

There are multiple methods for harvesting partial-thickness skin grafts.1,5,6,10,13 One method uses varioustypes of freehand skin graft knives and blades. Depth

control can be a concern, although several types ofknives have depth-control mechanisms.5 Examples offreehand devices include safety razors (although hard tofind), scalpel blades, and skin graft knives.5,14 Alterna-tively, several dermatomes have been used to obtainsplit-thickness skin grafts in dogs, thereby producing amore consistent result.1,6,14 Examples include the Zim-mer Dermatome (Zimmer Manufacturing, Warsaw,IN), the Brown Electric Dermatome (Zimmer Manu-facturing), and the disposable Davol/Simon CordlessDermatome (Davol, Cranston, RI).1,15 Dermatome usehas also been described in humans and horses.16–18

Booth reported an 88% graft acceptance rate of split-thickness autogenous skin transplantation in horses.16

Graft donor sites are relatively flat surfaces such as thelateral thoracic wall.6,10,13 However, the ventral thorax,lateral thigh, back, and neck have been described assplit-thickness graft donor sites in dogs.6,9,15 Followingaseptic preparation of the donor site, sterile saline maybe injected subcutaneously to assist in elevating the skin

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Partial-Thickness Skin Grafting for Large Thermal Skin Wounds in Dogs 203CE

Medical complications associated with large thermal skin wounds must be treated aggressively

before, during, and after surgery.

from the underlying bony structures in very thindogs.6,10,13 Next, the skin should be lubricated with ster-ile water-soluble lubricant or sterile mineral oil. Theblade of the dermatome should also be lubricated. Alever and an exchangeable base plate on the dermatomedetermine the thickness and width of the graft, respec-tively. Thickness of the graft can be selected from 0 to0.76 mm. A graft 0.38-mm thick is usually selected foruse on dogs.6 Graft harvesting requires a team of sur-geons. A minimum of three surgeons is needed, with theprimary surgeon operating the dermatome and assistingwith holding the skin taut. One assistant surgeon holdsthe skin taut in the opposite direction as does the pri-mary surgeon. The second assistant surgeon elevates thegraft as it is being harvested (Figure 2), meshes thegraft, and then places it on the recipient site.

Meshing the graft can expand it by three to nine timesits original area.1 Templates for graft meshing areselected based on the amount of expansion necessary.Meshing a graft can be performed either by hand, usinga No. 11 or 15 scalpel blade, or using a mesh graftexpansion unit1,5,6 (Figure 3). The use of a scalpel blade isgenerally reserved for full-thickness grafts.1 When usinga mesh graft expansion unit, a dermatome-harvestedpartial-thickness graft is placed dermal side down on thealuminum block with staggered, notched, parallel rows ofcutting blades (Padgett Instruments, Kansas City, MO).A Teflon roller is then passed over the graft in the direc-tion of the blades to cut slits in the graft. Repeated appli-cation and roller compression may be needed for com-plete cutting of the graft.1,5,6 Meshing the graft alsoallows fluid drainage from beneath the graft.6,19

The grafts should be placed on the wound immedi-ately. If this step must be delayed, the skin graftsshould be placed in gauze sponges moistened withsterile saline. Grafts should be placed on the wound sothat they overlap the wound edges by 1 to 4 mm.6,10

The graft can then be carefully attached by simpleinterrupted sutures or staples to the surrounding skin,and tacking sutures can be used to hold meshed graftsto the central regions of the wound and to assist inpulling the graft into concavities.1,5,6,10,14,15,20 Carefulattention is required while placing these tackingsutures to address and limit bleeding.1 Affixing thegraft to the surrounding skin with tissue adhesives hasalso been documented in several species.21–23 Fibringlues are preferred by many human surgeons for theirhemostatic and adhesive effects and convenience ofapplication.21 In humans, fibrin glues remain the mostversatile and have proven clinical efficacy in improvingskin graft survival and in decreasing blood loss whengrafting large burn sites.23 In dogs, a recent study eval-uated the tensile strength of sutured skin incisionswith and without the application of fibrin glue. Resultssuggested a significant increase in tensile strength inthe fibrin glue group.21

Partial-thickness donor sites do not require primaryclosure, which is one of the major advantages of thistechnique. A disadvantage of partial-thickness skingrafting is that donor sites managed as open woundstend to be more painful than if they were excised andprimarily closed.6 After placement of the graft, thewound should be gently irrigated with saline solution or



Figure 2. Intraoperative view of a Zimmer Dermatome(Zimmer Manufacturing) in use by a team of surgeonsharvesting a partial-thickness skin graft.

Figure 3. A mesh graft expansion unit. Templates forgraft meshing are selected based on the amount of expansionnecessary. Meshing a skin graft expands the total surface area bythree to nine times.

thrombin before applying the dressing.1,6,20 Antibioticointment on a finely woven, nonadherent dressing orpetrolatum-impregnated gauze commercially purchased orprepared by the surgeon can be applied to the wound fol-lowed by absorbent bandage layers. The bandage shouldbe secured with circumferential elastic tape on the limbs orumbilical tape tied through suture loops anchored in theskin for trunk, abdominal, and perineal areas.1,6

POSTOPERATIVE MANAGEMENTFailure of partial-thickness skin graft survival can be

caused by motion of the graft over the wound bed, infec-tion, or hematoma and seroma formation beneath thegraft, which prevent adhesion and capillary linkup.1,10,24

The adherence and revascularization process occurs overthe first 48 to 72 hours.1,5,6,15,24 This is a staged processthat functions as a continuum involving graft adherence,plasmatic imbibition, inosculation, and the penetrationand ingrowth of new vessels.1,5,6 Initially, a fibrin networkadheres the graft to its bed. Once the cut vessels dilate,the fibrinogen-free, serum-like fluid and cells areabsorbed into the graft.1,5,6,14,15,25 This process in whichcapillary action pulls cells and serum into dilated graftvessels is called plasmatic imbibition. Inosculation is theanastomosis of graft vessels with recipient bed vessels ofapproximately the same diameter and takes place as earlyas 22 hours after graft placement.5,6,14,24

Postoperative immobilization and preventing the dogfrom molesting the graft are critical components of theinitial graft adherence process. Immobilization can beachieved by casts/splints, sedation, or general anesthesia.Immobilization choices should be made through a com-bined assessment of patient status, size and location ofthe skin grafted sites, and financial concerns of the own-ers. If general anesthesia is deemed most appropriate forinitial postoperative immobilization, controlling compli-cations associated with long-term anesthesia (e.g.,hypotension, hypothermia, aspiration pneumonia, renalcompromise) is of utmost concern.

The first bandage is usually changed 48 hours aftersurgery.6,10 Because of the risk of contamination or graftmovement, the longer the intervals between bandagechanges, the better.2,5,6,9 Skin grafts near joints and high-movement areas can pose a significant challenge withimmobilization, and grafts over pressure points requirepressure relief. Casts and splints may be used in con-junction with wound dressings to aid in graft immobi-lization,5,20 but improper placement or slippage may putdamaging bandage compression on the grafts as well.

At every bandage change, skin graft viability should beassessed based on color, swelling, and adherence to thewound bed. Colors to note are pink, blue (cyanotic),black, and white. Pink indicates that the graft is under-going revascularization. Blue suggests that cyanosis isoccurring, which indicates congestion of the graft withresultant fluid and erythrocyte embedment. The eryth-rocytes within the graft temporarily lose oxygen and pro-duce a blue color. As the graft revascularizes, the cyanosissubsides as the oxygen content increases. Areas of thegraft that appear white immediately after graft place-ment on the recipient site are due to vasospasm of intra-dermal vessels. As plasmatic imbibition and revascular-ization occur, the vasospasm subsides and the graftbecomes pink. A graft or part of a graft that remainswhite indicates that revascularization has not occurred.The wound bed should be checked for discharge and afoul smell. Culture and sensitivity samples should be col-



The donor sites of partial-thickness skin grafts arepainful. The pain management protocol varies amongpatients and is determined by patient assessment andstatus, preexisting thermal injuries, the extensivenessof the skin graft harvests, and concomitant medicalproblems. Analgesics can be given transdermally,intravenously (intermittent or constant-rate infusion[CRI]), intramuscularly, or subcutaneously atrecommended intervals. The following drugs are notthe sole or combined means of therapy but areoptions that can be introduced into a painmanagement protocol, which is ultimately theresponsibility of the attending clinician.Fentanyl transdermal patch25 µg/hr (<10 kg)50 µg/hr (10–25 kg) 75 µg/hr (>25 kg)Place 12–24 hr before surgery Fentanyl0.01–0.05 mg/kg IV (loading dose) 0.001–0.004 mg/kg/hr CRI (maintenance dose)Hydromorphone HCl0.05–0.1 mg/kg SC or IM q4hOxymorphone HCl0.05–0.1 mg/kg SC, IM, or IV q4–6h (maximumdose: 4.5 mg/dog)Ketamine HCl 0.5–1 mg/kg IV (loading dose)0.5–1 mg/kg/hr CRI (maintenance dose)

Pain Management for Partial-Thickness Skin Grafts

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Burn victims often present myriad clinical problemsrelated to both the initial injury and the medical andsurgical management of it. Examples of problemsincurred as a direct result of severe burns include pain,shock, smoke inhalation, and hemorrhage. Theseproblems must be addressed before the burns themselvescan be treated. Blood and protein loss, wound infectionand sepsis, and inadequate nutritional support are allpossible sequelae of severe burns and must be addressedas well. The following cases describe the medical andsurgical management of severely burned dogs usingpartial-thickness skin grafting.

Case 1A 2-year-old intact female mixed-breed dog was

presented after sustaining malicious thermal burnsinvolving a chemical accelerant 5 days previously. Shehad been treated initially with cool water baths, IV fluids,analgesics, and antibiotics. The burn wounds involved theentire caudal abdomen and inguinal areas, bilateralmedial thighs, medial crus on the left pelvic limb, leftflank, and left axillary region. Initial surgical wounddebridement was performed and a percutaneousendoscopic gastrostomy tube placed. Over the next 10days, the dog was anesthetized daily, the wound wasdebrided, and the bandages were changed (A). Duringthis period, the patient also received whole-blood andplasma transfusions and gastrostomy tube feedings if oralintake did not meet daily requirements.

A partial-thickness skin grafting procedure wasperformed 15 days after presentation. A ZimmerDermatome (Zimmer Manufacturing) was used to

collect partial-thickness skin grafts from the right lateralthoracic region. The grafts were meshed to cover an areathree times the original size of the graft. The grafts wereapplied and secured with simple interrupted 4-0 nylonsutures. All of the wounds were covered with tripleantibiotic ointment, and a nonadherent dressing wasapplied over the graft and donor sites.

The patient was maintained under general anesthesiawith mechanical ventilation for the first 24 hours. Thedog was premedicated with oxymorphone hydrochloride(0.1 mg/kg IM) and glycopyrrolate (0.01 mg/kg IM),induced with ketamine hydrochloride (6 mg/kg IV) anddiazepam (0.3 mg/kg IV), and maintained on inhalantisoflurane in 100% oxygen and a continuous-rateinfusion of ketamine hydrochloride (1 mg/kg/hr IV).Hydromorphone (0.05 mg/kg IV q6h) was given asneeded to address pain and lower the amount of inhalantanesthesia required for a continuously smooth plane ofanesthesia. Injectable analgesics and sedatives, includingmorphine sulfate (0.5 mg/kg SC as needed), ketaminehydrochloride (5 mg/kg IV as needed), and diazepam(0.25 mg/kg IV as needed) were used for the following4 days. A urinary catheter was used for 5 dayspostoperatively to evaluate ins and outs.

Over the next week, the patient was kept sedated asneeded and the wounds were inspected and cleaned asnecessary. IV fluids and antibiotic therapy with lactatedRinger’s solution (50 ml/hr) and cefazolin sodium (22 mg/kg IV q8h), respectively, were also continued atthis time.

All of the grafted skin healed on the wound. Ondischarge of the patient 3 weeks after surgery, only a fewsmall epithelial defects were evident on the caudal

Case Reports

A. Ventrodorsal view of the abdomen 15 days afteraggressive wound management. Healthy granulation tissueis seen throughout the full-thickness skin defects.Tacking loopsutures at the periphery of the wounds were used to assist inanchoring tie-over bandages.

B. Ventrodorsal view of the abdomen 21 days afterpartial-thickness skin graft application. Only a few smallepithelial defects are evident on the caudal abdomen, whichhealed by reepithelialization over the next 3 days.



Case Reports (continued)

abdomen, which healed by epithelialization (B). Whenthe dog was examined 9 months after surgery, all graftedareas were covered with smooth, hairless, pigmentedskin (C).

Case 2A 3-year-old intact female boxer was admitted for

treatment of severe burns incurred in an accidentalhouse fire 1 month previously. The dog was treated bythe referring veterinarian with antibiotics, plasmatransfusions, and pain medication. The burns weremanaged using surgical debridement followed by dailywhirlpool baths and regular bandage changes. Oncehealthy beds of granulation tissue formed, the dog wasreferred for skin grafting.

On physical examination, the patient was brightand alert but thin, with a body condition score of 2/5.The owners reported that the dog had originally lostapproximately 25 lb (11.4 kg) since the fire but hadrecently started to gain weight. An initial serum chemistryand complete blood cell count revealed hypoalbuminemia(albumin level: 2.1 g/dl; reference range: 2.5 to 4.2 g/dl),regenerative anemia (hematocrit level: 27.2%; referencerange: 35% to 57%), and neutropenia (polymorphonuclearcells: 2,726/µl; reference range: 2,900 to 12,000 cells/µl).Full-thickness burns covered most of the dog’s right side,including the lateral thorax and abdomen, lateral aspect ofthe axilla and brachium, and caudal aspect of theantebrachium. In addition, the caudal aspects of bothstifles and the perineum suffered full-thickness burns. Thedog’s left side was not as severely affected, with burnscovering the lateral side of the thigh and the digital padsof that foot. Partial-thickness burns on the top of thedog’s head were healing.

On initial evaluation of the dog, it was determinedthat the extent and location of the burns and the

degree of wound contracture already present warrantedtreatment with partial-thickness skin grafting.Contracture of the full-thickness burns in the perineumhad deviated the vulva and anus slightly to the right.Prevention of further wound contracture was necessary toavoid impairment of urination or defecation and toprevent dystocia in case of future pregnancy. Contractureof the burns on the patient’s right brachium and axillawere interfering with normal extension of the shoulderand restricting the forward stride. If left unabated,further contracture of the caudal stifle wounds was likelyto prevent normal stifle extension. Partial-thicknessskin grafting was determined to be the treatment ofchoice because it would allow coverage of all theburn, but the donor sites could be allowed to heal byreepithelialization.

The dog was anesthetized daily with propofol (6mg/kg IV) and isoflurane in 100% oxygen for surgicaldebridement and wound assessment. The burns weretreated with silver sulfadiazine cream and rebandaged.Pain was controlled with a transdermal fentanyl patch(50 µg/kg/hr) and hydromorphone (0.05 mg/kg IV q6h)as needed. Hypoalbuminemia, likely a result of proteinloss directly through the wound, was treated with plasmatransfusions as needed.

Before surgery, a plan for postoperativeimmobilization and nutritional supplementation wasmade. Dorsal recumbency was necessary in this dogbecause lateral or sternal recumbency would put pressureand shear forces on graft sites. General anesthesia withpositive-pressure ventilation for 48 hours postoperativelywas deemed the most effective and practical method ofkeeping the patient immobilized. Nutritionalsupplementation with a parenteral amino acid solution inthe postoperative period was chosen. Although the dogate well before surgery, we were concerned that theprolonged anesthesia necessary during and after surgerywould prevent us from providing nutrition orally andprove detrimental to an already thin animal. Feedingtubes were not good options in this dog becausegastrostomy or enterostomy tubes would interfere withthe skin graft donor site and nasoesophageal andesophagostomy feedings might have predisposed thepatient to aspiration while anesthetized and dorsallyrecumbent. The risks of metabolic disorders or sepsisassociated with total parenteral nutrition outweighed thebenefits that would have been gained during the shortperiod in which nutritional support was necessary.

After 4 days of hospitalization and daily surgicaldebridement of the wounds, the granulation tissue wasadequately prepared for skin grafts. Before surgery, awhole-blood transfusion was administered and anindwelling urinary catheter placed. After premedicatingthe patient with hydromorphone (0.1 mg/kg IM) andglycopyrrolate (0.01 mg/kg IM), anesthesia was induced

C. Ventrodorsal view of the abdomen 9 months afterpartial-thickness skin graft application. All grafted areaswere covered with smooth, hairless, pigmented skin.


with propofol (10 mg/kg IV) and maintained withisoflurane in 100% oxygen. During surgery, lactatedRinger’s solution was administered (10 ml/kg/hr IV)and dobutamine (5 to 10 µg/kg/hr IV) was added asneeded to treat hypotension. Anesthetic complicationsincluded hypothermia (<88.4°F) and transienthypotension (systolic blood pressure: 60 mm Hg).Partial-thickness skin grafts were harvested from the leftlateral thoracic wall and the ventral sternum with aZimmer Dermatome (Zimmer Manufacturing) andmeshed to cover an area three times the original size ofthe grafts. Because of the extent of the grafting andexcessive time necessary to suture all the grafts to thewound beds, we applied the partial-thickness skin graftsto the wound beds without sutures. We suspected thegrafts would adhere to the wound beds within 24 hoursif the wounds were treated gently. Donor and recipientsites were bandaged with antibiotic ointment,nonadherent pads, and moistened laparotomy pads usingtie-over bandages.

After surgery, the dog was immobilized with generalanesthesia for 2 days to allow the partial-thickness skingrafts to adhere properly to the underlying wound beds.Such immobilization prevents fragile grafts from being

dislodged by the shear forces caused by excessivemovement. In addition to a low dose of isofluraneanesthesia for immobilization, the dog received aconstant-rate infusion of ketamine hydrochloride (1mg/kg/hr IV) and hydromorphone (0.05 mg/kg IVq4–6h) for pain management. Total solid, hematocrit,blood glucose, and blood-gas levels; urine output; bloodpressure; central venous pressure; complete blood cellcount; and blood chemistries were monitored daily. Ourmain concerns during the immediate postoperativeperiod were inadequate hydration with resultanthypotension and renal hypoperfusion, hypothermia,inadequate nutrition, urinary tract infection, woundinfection, aspiration pneumonia, and graft failure.

Bandages were changed every 1 to 2 days aftersurgery, and the grafts healed well. The patient’s rightand left sides are shown 5 days after surgery (D and E).Graft healing and epithelialization was apparent, and thedonor sites healed rapidly after treatment withantibacterial ointment and routine bandage changes. Thedog’s right and left sides are shown 18 days after surgery(F and G). Epithelialization occurred rapidly, although afew small areas of grafted skin died. Long-term follow-up with the owner (22 months after surgery) revealed

Case Reports (Continued)

Case Reports (continued)



D. Right lateral view 5 days after surgery of a 3-year-old female boxer that had partial-thickness skingrafting for severe thermal skin wounds sustained in ahouse fire. Extensive wounds can be seen along the lateralabdomen, trunk, and forelimb and along the caudolateralhindlimb.Wound contraction, epithelialization, and skin graftsurvival are apparent.

F. Right lateral view 18 days after surgery. Dramatichealing can be visualized with almost complete skin coverage.Only a few small areas of grafted skin died and healed bysecond intention.

G. Left lateral view 18 days after surgery. Completeepithelialization is noted throughout the donor sites on thethorax and along the graft recipient sites on the thigh.

E. Left lateral view 5 days after surgery. Donor sitereepithelialization is evident on the thorax and abdomen, andhealing of a partial-thickness skin graft recipient site can beseen on the thigh.

that the dog was active, with normal function of alllimbs. Complete coverage of the previous wounds withskin was evident, and a small amount of hair regrowth

had occurred, although a small 4 × 4–cm region of skinjust dorsal to the right elbow has been persistentlypruritic.

lected if infection is suspected. After the first bandagechange, subsequent bandage changes can be repeated ina similar fashion every 2 to 3 days, depending on graftappearance.1,6 Donor sites can be covered with a light

bandage containing a single layer of petrolatum-impreg-nated gauze or antibiotic-coated nonadherent pads.Donor site bandage changes can coincide with recipientsite bandage changes. Special attention should also be

(continued from p. 206)



directed toward pain control, systemic monitoring forsepsis, and testing for hypoalbuminemia and anemia.

CONCLUSIONThermal wounds in dogs can range from minor epi-

dermal irritations to extensive full-thickness skindefects. We have had successful surgical reconstructiveresults with partial-thickness skin grafting of large ther-mal skin wounds when other forms of full-thicknessrepair are not usable as a sole or combined means of sur-gical therapy. This technically challenging surgical treat-ment modality is not intended to replace full-thicknessskin grafting but instead is intended to add to thereconstructive options useful in managing large thermalskin wounds in dogs. Patient individualization andassessment determine adjunctive surgical needs, andconsideration of referral to a highly equipped surgicalcenter for partial-thickness skin grafting is an option.

ACKNOWLEDGMENTThe authors thank Drs. Christine Egger (cases 1 and 2), Karen Cornell(case 1), Clarence Rawlings (case 2), and the students and staff of TheUniversity of Georgia Small Animal Teaching Hospital for their contribu-tions to intensive patient management.

REFERENCES1. Pavletic MM: Atlas of Small Animal Reconstructive Surgery, ed 2. Philadelphia,

WB Saunders, 1999, pp 11–32, 107–119, 131–296.

2. Ramsey DT, Pope ER, Wagner-Mann C, et al: Effects of three occlusivedressing materials on healing of full-thickness skin wounds in dogs. Am J VetRes 56(7):941–949, 1995.

3. Swaim SF: Advances in wound healing in small animal practice: Current sta-tus and lines of development. Vet Derm 8(4):249–257, 1997.

4. Swaim SF, Gillette RL: An update on wound medications and dressings.Compend Contin Educ Pract Vet 20(10):1133–1144, 1998.

5. Swaim SF: Surgery of Traumatized Skin: Management and Reconstruction in theDog and Cat. Philadelphia, WB Saunders, 1980, pp 423–476.

6. Swaim SF: Skin grafts, in Slatter DH (ed): Textbook of Small Animal Surgery,ed 3. Philadelphia, WB Saunders, 2003, pp 321–338.

7. Bauer MS, Pope ER: The effects of skin graft thickness on graft viability andchange in original graft area in dogs. Vet Surg 15(4):321–324, 1986.

8. Pope ER: Effect of skin graft preparation and graft viability on the secondarycontraction of full-thickness skin grafts in dogs. Am J Vet Res 46(12):2530–2535, 1985.

9. McKeever PJ, Braden TD: Comparison of full- and partial-thickness autoge-nous skin transplantation in dogs: A pilot study. Am J Vet Res 39(10):1706–1709, 1978.

10. Probst CW, Peyton LC, Bingham HG, et al: Split-thickness skin grafting inthe dog. JAAHA 19:555–568, 1983.

11. Spreull JSA: The principles of transplanting skin in the dog. JAAHA 4:71–84,1968.

12. Lee AH, Swaim SF: Granulation tissue: How to take advantage of it in man-agement of open wounds. Compend Contin Educ Pract Vet 10(2):163–168,170, 172–173, 1988.

13. Fox SM, Probst CW: Split-thickness autogenous skin transplantation in adog. Vet Med Small Anim Clin 77:782–787, 1982.

14. Hedlund CS: Skin grafts, in Fossum TW (ed): Small Animal Surgery. St.Louis, Mosby, 1997, pp 128–134.

15. Swaim SF: Skin grafts. Vet Clin of North Am Small Anim Pract 20(1):147–175,1990.

16. Booth LC: Split-thickness autogenous skin transplantation in the horse.JAVMA 180(7):754–757, 1982.

17. Frankland AL: Autologous, split skin transplantation on the lower limbs ofhorses. Vet Rec 104(26):590–595, 1979.

18. Sidebottom AJ, Stevens L, Moore M, et al: Repair of the radial free flapdonor site with full or partial thickness skin grafts. Int J Oral Maxillofac Surg29(3):194–197, 2000.

19. Pope ER: Skin grafting in small animal surgery. Part II: Full-thickness skingrafting techniques. Compend Contin Educ Pract Vet 10(9):1068–1077, 1988.

20. McGregor AD, McGregor IA: Fundamental Techniques of Plastic Surgery andTheir Surgical Applications, ed 10. London, Churchill Livingstone, 2000, pp1–99.

21. Park W, Kim WH, Lee CH, et al: Comparison of two fibrin glues in anasto-moses and skin closure. J Vet Med 49(7):385–389, 2002.

22. Schumacher J, Ford TS, Brumbaugh GW, et al: Viability of split-thicknessskin grafts attached with fibrin glue. Can J Vet Res 60(2):158–160, 1996.

23. Gosain AK, Lyon VB: The current status of tissue glues. Part II: For the adhe-sion of soft tissues. Plastic and Reconstructive Surgery 110(6):1581–1584, 2002.

24. Pope ER: Skin grafting in small animal surgery. Part I: The normal healingprocess. Compend Contin Educ Pract Vet 10(8):915–923, 1988.

25. Converse JM: Plastic surgery and transplantation of skin, in Skin Surgery.Springfield, IL, Charles C. Thomas, 1970, pp 161–182.

ARTICLE #3 CE TESTThis article qualifies for 1.5 contact hours of continuing education credit from the Auburn University College of Veterinary Medicine. Subscribers who wish to apply this credit to fulfill state relicensure requirements should consult their respective stateauthorities regarding the applicability of this program.To participate, fill out the test form inserted at the end of this issue.

CE

1. Which of the following statements regarding largethermal skin wound management (involving morethan 15% to 20% of total body surface area) is false?a. Large wounds should initially be managed appropri-

ately to promote granulation tissue before definitivesurgical management.

b. Possible detrimental complications that can be associ-

ated with large skin wounds include sepsis, hypoprotein-emia,electrolyte imbalances,dehydration, and anemia.

c. The size and location of the wound play a vital role inthe decision-making process of surgical management.

d. Primary closure is the definitive treatment of choiceand should be performed regardless of the size andlocation of a large thermal skin wound.


2. Partial-thickness skin grafting a. requires surgical closure of the donor site.b. can be performed using multiple methods of graft-

harvesting techniques.c. is the best choice for all surgical wound management.d. is easiest when the distal limbs are used for donor

site harvesting.

3. In terms of the selection and consistency of graftthickness, the ________________ is(are) best for partial-thickness skin graft harvesting.a. scalpel blade c. safety razorb. dermatome d. elevator and curette

4. __________ is the process in which capillary actionpulls cells and serum into dilated graft vessels.a. Inosculation c. Imbibitionb. Vasospasm d. Innidiation

5. Regarding partial-thickness skin grafting, theinitial postoperative bandage change should beperformeda. within approximately the first 6 hours after surgery.

b. at discharge of the patient.c. on approximately day 10 after surgery.d. approximately 2 days after surgery.

6. Little or no hair growth is most commonly asso-ciated with a. full-thickness skin grafting.b. partial-thickness skin grafting.c. skin flap techniques.d. primary or delayed primary closure.

7. Which of the following statements regarding themanagement of large skin wounds using partial-thickness skin grafts is true? a. Postoperative bandaging of the recipient sites can be

advantageous but poses a risk to skin graft viability.b. Hematoma formation beneath the skin graft is advan-

tageous to skin graft adherence.c. Partial-thickness grafts require primary closure and

hence are less painful than full-thickness grafts.d. Meshing the graft delays reepithelialization and can

prevent graft expansion.



8. Which of the following is not a benefit of granu-lation tissue?a. aids in filling in the wound spaceb. supplies vascular linkup for skin graft nourishmentc. functions as a protective barrierd. negates the need for postoperative bandaging

9. Postoperative immobilization of a patient to pro-mote graft adherence cannot be performed byusinga. casts/splints.b. compression bandages.

c. sedation.d. general anesthesia.

10. When harvesting a partial-thickness skin graftwith a dermatome, which of the following doesnot aid in ease and consistency?a. applying thrombin to the epithelial surface b. lubricating the skin with sterile mineral oilc. pulling the skin tautd. subcutaneously injecting sterile saline beneath the

donor site

Documents

Article #3 CE Partial-Thickness Skin Grafting for …...defect created can reepithelialize within 3 weeks.1 Therefore, the amount of donor skin available for par-tial-thickness grafting