Conquering Plastic Surgery Complications In Wound Care

   The use of plastic surgery techniques has increased dramatically among podiatric surgeons over the past few years. The most useful techniques involve the use of skin grafts and local flaps, which can help solve some difficult wound closure problems. The increased usage of these techniques is partially due to the fact that some are relatively easy to learn and one can learn the basics at weekend workshops. However, as one might expect with any surgical procedure, complications can arise.    Fortunately, severe complications are infrequent but one must handle them properly when they do occur.    Surgeons have employed skin grafting in the lower extremity for many years but one may encounter complications. Hematoma or seroma accumulation under the graft can disrupt the contact with the underlying bed, causing the graft to lose its source of nutrients and prevent neovascularization. This complication occurs more commonly with full thickness grafts than split thickness grafts, which are often meshed.    Meshing of the graft not only increases the surface area the graft can cover, it also allows fluids to drain, preventing possible accumulation. Full thickness skin grafts are not usually meshed but adequately “pie crusting” or making small slits in these grafts will also prevent the accumulation of fluids. Adjunctively employing a secured compressive dressing, such as a “tie over” or “stent” dressing, can prevent fluid accumulation and will also keep the graft in place during patient movement.    Keep in mind that dressing changes during the initial few days after surgery can disrupt the tenuous bond between the graft and the bed. Be aware that the graft may appear white or dusky initially but one should not confuse this with a non-viable graft. Using a finely meshed, non-adherent barrier as the first layer of the dressing can prevent the graft from sticking and being pulled off with the dressing. Adding a saline- or glycerin-soaked gauze as the next layer will also aid in preventing the dressing from sticking and also help prevent the graft from drying out.    If one inadvertently removes the graft with the first dressing change, one may reapply it under sterile conditions and the graft may still take. I have found it useful to do all my own dressing changes in patients with skin grafts in order to prevent this complication.

Pertinent Insights On Preventing Skin Graft Failure

   In my experience, one can often trace graft failure to inadequate preparation of the wound bed. Skin grafts tend to take very rapidly to clean, well-vascularized tissue. During the first dressing change, I would expect to see the graft already adhered to the bed. Applying the graft directly over exposed bone, tendon or fascia will often fail. The graft may initially take if adequate periosteum or tendon sheath is present but may fail later due to shear forces. In these situations, surgeons may use a skin graft as a temporary fix until they are able to perform a more definitive procedure.    Also be aware that applying a graft over an infected wound is doomed to failure. If one attempts to place a graft on an infected wound, it will not adhere to the wound bed and will not help reestablish blood flow. One must achieve appropriate wound sterility prior to graft application.1    Long-term success of skin grafts in the foot depends on protecting the grafted area from weightbearing and shearing forces. Grafted tissue will not withstand these forces in the long run. Ensuring the presence of adequate soft tissue under the graft will help protect it.    Skin grafts also tend to contract significantly over time. The thinner the graft, the more contracture one can expect to see. These contractures can be problematic, especially when they cross over joints.

Ensuring The Success Of Local Flaps

   Local flaps are very useful in the foot for covering defects on weightbearing surfaces where a skin graft would most likely fail. Researchers have described many different flaps, all of which have various pros and cons.2 There are many factors surgeons must consider in order to choose an appropriate local flap. These factors include the location, size, shape and depth of the defect as well as the amount, type and mobility of the surrounding skin.    For example, the skin on the plantar surface of the foot adheres tightly to the underlying fascia, making rotation of the flap more difficult if the flap is poorly designed. Preoperative planning is essential to preventing excessive tension across the flap. Excessive tension can compromise the vascularity of the flap or lead to wound dehiscence. Trying to determine how much tension is excessive can be difficult since the amount of tension a flap may tolerate varies from patient to patient and depends upon multiple factors. As a general rule of thumb, if a flap can hold its new position without breaking a 4-0 monofilament nylon suture, the tension is probably not excessive.    When one rotates a flap, blanching of the flap may occur. The first step I take intraoperatively in this situation is to raise the head of the table and apply a warm saline compress. The blanching may be due to vasospasm and may subside after several minutes. If the flap fails to “pink up,” there may indeed be too much tension across the flap and several techniques can relieve this tension.    Removing a few of the sutures may be enough to allow the flap to perfuse. If this fails, one should remove all the sutures and allow the flap to return to its original position. If the flap fails to perfuse when it is back in its original position, the vascularity to the flap may have been compromised and this is a concern.    In this situation, I would leave the flap in its original position and secure it in place. The vascularity of the flap may increase over the next few days by a process referred to as a delay phenomenon. This process begins when the surgeon raises the flap and cuts vessels on three sides of the flap. The blood flow through the remaining side will increase its capacity over the next few days. This may allow the patient to return to the operating room and one can make another attempt to rotate the flap.    If one places the flap in its original position and it does perfuse, then excessive tension is the problem. The surgeon can then perform undermining of the tissue around the defect, taking care to avoid undermining the flap base. Undermining the surrounding tissue instead of the flap base will cause the least amount of disruption of the blood supply to the flap.    One should proceed to rotate the flap once again. If it blanches again, there is still too much tension. Surgeons may attempt to undermine the base of the flap but keep in mind that doing so can compromise the vascularity to the flap.    Accordingly, one should do this with great caution and with the least amount of undermining necessary to decrease the tension.    Finally, make a back cut at the base of the flap where one will find most of the tension. Use this technique with caution since it will narrow the base of the flap and reduce the inflow of blood. If blood flow into the flap continues to be restricted, place the flap back in its original position and bring the patient back to the operating room after the flap has had a chance to increase its vascularity.

How To Address Dog Ears

   Dog ears are an inevitable consequence when tissue rotates around an axis. Excessive dog ears occur when a flap rotates around a large angle or as a result of a poorly designed flap. The surgeon does not need to address most dog ears since they will often flatten in time. Addressing a dog ear at the time of the original surgery can further compromise the flap so one should exercise great caution. If necessary, surgeons can deal with dog ears in the future once the flap is fully revascularized.3    In a similar fashion, involutions of tissue can occur when tissue rotates. Involutions can occasionally be problematic and lead to callus formation and ulceration. In these cases, one can address the excess tissue in a manner similar to dog ears. Avoid removing excessive tissue from the plantar surface of the foot since this is very unique tissue and it is paramount to preserve as much of it as possible. One can accomplish this by choosing the correct flap for the particular defect.    Surgeons should keep in mind that recurrent ulcers are common in the neuropathic foot and any excess tissue may be useful in future procedures. When choosing a flap, one should also consider the possibility of needing to elevate and rotate a flap a second time for a recurrent ulceration. Some flaps are more amenable to this than others.

Key Insights On Preventing Post-Op Flap Failure

   Postoperative flap failure is a devastating complication that surgeons occasionally encounter when using plastic surgery techniques. During dressing changes, one should carefully inspect the flap for infection and viability. The flap’s capillaries’ refill and color should be consistent with the surrounding tissue. If a flap appears dusky or cyanotic, venous congestion may be occurring as blood finds it easier to enter the flap than to exit the flap. This congestion will usually resolve but can cause the flap to swell and may ultimately compromise its viability.    Podiatrists should emphasize to patients the importance of strict elevation of the foot during the initial postoperative period in order to prevent swelling and flap failure. If a flap appears white and lacks a capillary refill, have the patient place his or her foot in a dependent position and once again observe its color. If there is reestablished blood flow in this position, have the patient alternate between elevation and dependency. I will also have the patient discontinue the use of ice and may consider warm compresses.    If the flap still fails to perfuse in a dependent position, removing a few sutures and securing the flap with a dressing is the next step in an attempt to salvage it. Carefully monitor flaps in this situation since they may go on to necrose. A flap that turns black is an ominous sign. I have found that flaps on the back of the heel are the most prone to necrose. This portion of the foot is notorious for wound complications. My personal experience with random blood flow flaps in this area has shown only marginal success. In patients with less than ideal circulation, I now lean towards an axial-based flap if possible. A lateral calcaneal artery flap has proven useful in this area.    Recently, Jolly, et. al., renewed interest in using a reverse flow sural artery neurofasciocutaneous flap for defects in the heel and ankle.4 Initially when encountering a necrotic appearing flap, I may simply monitor it as long as it remains free of infection. Due to decreased blood flow, the epithelium may slough. This may cause the flap to appear necrotic but there may still be viable tissue under the flap. If I am not sure if a flap is necrotic, I may do some light superficial debridement. If this produces bleeding, I will stop and monitor the flap carefully over the next week. If debridement does not produce bleeding or if infection occurs, one should proceed with more aggressive debridement as well as the appropriate antibiotics.

Emphasizing The Importance Of Patient Compliance

   Patient compliance is critical after plastic surgery procedures and can cause the surgeon a great deal of anxiety and concern. The most common compliance issue I see is when patients ambulate too early postoperatively. Since many of these procedures are performed on neuropathic feet, the patient may not have any pain and therefore may be tempted to try early weightbearing. I emphasize to the patient that even a few steps may compromise the flap and the patient may end up with a wound larger than the original wound. Modifying a surgical boot to offload a flap in a patient who is unable to be non-weightbearing may be effective in certain situations but I prefer to put the patient in a wheelchair. Admitting a patient to a nursing facility for a few weeks is another alternative.    Patients with diabetes must strictly control their glucose levels postoperatively. Increased glucose levels inhibit healing and increase the risk of infection. Controlling glucose levels can be difficult due to the required inactivity.    Smokers must refrain from any tobacco products during the healing process. Often patients fail to understand the detrimental effects that nicotine has on the healing process. I have found it useful to explain the immediate vasoconstrictive properties nicotine has on the already reduced blood flow to the flap. If a patient smokes a pack a day, his or her healing may be significantly reduced for much of the day.    Compliance in this regard can be very challenging since the patient is spending a great deal of time immobile. It is important to discuss these issues preoperatively with patients, especially those who smoke, so hopefully they will be better prepared to occupy their time with other activities.

In Summary

   Plastic surgery techniques are an extremely valuable tool for handling difficult wound problems in the foot. However, they also provide some unique challenges when complications occur. As more and more surgeons add these procedures to their armamentariums, our profession is likely to see an increase in complications. In order to ensure reliable positive outcomes, one must emphasize proper preoperative planning, flap or graft choice, postoperative management, patient education and properly handling complications when they do occur. Dr. Storm is a Fellow of the American College of Foot and Ankle Surgeons and is board-certified by the American Board of Podiatric Surgery. He has a private practice in Bozeman, Mt.
 

References:

1. Krizek JJ, Robson MC. Biology of surgical infection. Surg Clin North Am 1975: 55: 1261-1267.
2. Storm TR, Lee MS. Plastic and reconstructive surgery. In: Banks A, Downey M, Martin D, Miller S, eds. McGlamrys Comprehensive Textbook of Foot and Ankle Surgery, 3rd ed. Philadelphia: Lippincott Williams & Wilkins, 2001: 1487-1521
3. Gusman D. Wound closure and special suture techniques. J Am Podiatr Med Assoc 1995;85:1-10
4. Jolly GP, Zgonis T. Soft tissue reconstruction of the foot with a reverse flow sural artery neurofasciocutaneous flap. Ostomy Wound Manage Jun 2004, 50(6) p44-9.