Current Concepts In Treating Ischemic Foot Ulcers
After this treatment, Dr. Allie says the revascularized, sterilized wound is ready for coverage, which could be with split thickness skin grafts (STSG), bioengineered skin or a wound vacuum assisted therapy with a Dermacyn-soaked sponge in the deeper wounds. He cites his recent “excellent” results with the early application of Apligraf (Organogenesis) in CLI patients after laser revascularization. He says he has also had success with Apligraf application in wound complications after coronary arterial bypass graft (CABG) and tibial bypass surgery.4,5
Dr. Karlock tries to keep the wounds clean, dry and uninfected. He also says clinicians should avoid debriding an ischemic wound to prevent adding “insult to injury.” He believes Betadine still plays a role until vascular bypass, etc. is undertaken. Dr. Karlock notes he also uses Iodosorb (Smith and Nephew) for these wounds. He avoids any aggressive wound enzymatic debridement.
Q: What new interventional procedures do you utilize?
A: For CLI revascularization, Dr. Allie uses several new products. He cites Excimer laser therapy for photoablation of atherosclerotic plaque and thrombus (clot), and the benefits of SilverHawk (FoxHollow) plaque excision. He also uses metal stents of sizes ranging from 2 to 22 mm and cryoplasty or cryotherapy, which delivers -10°C controlled balloon dilation to vessels to minimize injury and restenosis. Dr. Allie says mechanical thrombectomy removes recently formed clots and specialty balloons (cutting balloons) with small blades facilitating the treatment of calcified vessels.
In addition, he says one can facilitate interventional revascularization by using a host of new adjuvant technologies, including reentry catheters that permit wire crossing of long, totally blocked vessels, as well as distal protection devices or filters that facilitate the capture of macro- and microembolic debris that may result from the revascularization procedure.
Like Dr. Allie, Dr. Zarrinmakan cites the use of FoxHollow atherectomy and stents. He uses a vast variety of interventional modalities such as percutaneous balloon angioplasty and laser atherectomy. When such modalities fail or are not possible, he opts for bypass grafting or other surgical procedures.
Dr. Brenner says podiatrists should be aware of new alternatives to bypass and newer tools for revascularization so they can make appropriate referrals for patients who may benefit from these procedures. He cites Remote Endartectomy (Vascular Architects), a minimally invasive technique for treating femoral popliteal occlusive disease that a vascular surgeon would usually perform at the superficial femoral artery. With this procedure, the vascular surgeon can successfully excise large calcified plaques and strong results are not uncommon, according to Dr. Brenner.
Dr. Brenner suggests DPMs should also be aware of cryoplasty therapy (Boston Scientific), which he says offers promising results for treating popliteal and tibioperoneal disease.
Q: Do you have any insight on the timing of foot amputation and the bypass procedure?
A: “Amazingly, and this must be rectified, the facts are that 49 percent of the BK amputations presently done in the U.S. are being performed without even doing ABI studies,” asserts Dr. Brenner. “It is imperative that all diagnostic tests be performed by competent vascular specialists and/or radiological interventionists, who then should probably do endovascular procedures and/or bypasses to revascularize feet before any amputations are performed.”
Dr. Allie strongly suggests a bypass or percutaneous interventional procedure prior to considering amputation unless an obvious abscess or necrotizing fasciitis is present. He also recommends conservative, limited amputations when indicated as these procedures give the patient maximum opportunity to preserve tissue and function. Although he has advocated systemic hyperbaric oxygen (HBO) therapy, Dr. Allie has found 70 to 80 percent of the elderly CLI patients will have a contraindication or will not tolerate systemic HBO (due to CHF, pulmonary issues, etc.). He relates positive experiences with local extremity or topical oxygen therapy, noting he is encouraged with recent work at Ohio State where researchers are trying to provide the “science” of why this therapy works.