Factors such as moisture and compression are necessary for wounds to heal and obstacles such as pressure and friction need to be removed.
Above: Left image shows a venous ulcer before compression is applied. Right image demonstrates efficacy of compression therapy. Source: O. Fred Miller, III, M.D.
Basic principles of wound care will help heal most wounds, according to O. Fred Miller, III, M.D., emeritus director of dermatology at Geisinger Health System in Danville, Penn.
It is a myth that exposing wounds to the air will accelerate healing, Dr. Miller says. In an update on wound healing at the annual meeting of the American Academy of Dermatology, he explained that wounds require moisture for re-epithelialization.
Knowing the etiology of a wound, particularly knowing if it is venous or arterial, is key to effective management, Dr. Miller says, adding that most ulcers that present on the lower limbs are venous ulcers. Venous ulcers are more common in women, and their incidence increases with age.
Arterial ulcers need to "invariably" be referred to vascular surgeons, Dr. Miller says, explaining in this way adequate blood perfusion might be achieved with surgical intervention.
"Once limbs are re-vascularized, the ulcers can be healed with basic wound care," he says.
Ischemia is an essential characteristic to identify, for management of an ischemic ulcer will differ from an ulcer without ischemia. Never debride an ischemic/arterial ulcer prior to successful revascularization, he stresses.
"Ischemic ulcer pain is often relieved by standing or gravity," Dr. Miller says. "Patients may have pain while they are lying in bed. The pain from inadequate vascular perfusion can often be relieved by dangling the legs over the bedbed or walking around the room."
The ankle brachial index (ABI) measures blood pressure and checks for blood flow. Patients can be sent to the vascular laboratory to obtain an ABI. The venous duplex ultrasound is the gold standard to check for circulation in the veins of the legs. It is of value to also look at wave forms if patients have been sent to the vascular laboratory to have ABI measured. Monophasic wave forms, for example, are suggestive of ischemia, said Dr. Miller.
A large, circumferential venous ulcer before compression is applied (above). Venous ulcer treated with compression therapy without interruption until healed (below). Source: O. Fred Miller, III, M.D.
If thrombosis is present, a non-invasive procedure with use of radiofrequency or cauterizing laser can be performed to help destroy the perforator vein, so that there is no longer perforator vein reflux, Dr. Miller says.
If the ABI value is below 0.6, clinicians generally avoid the use of compression, but Dr. Miller notes that recent literature points to the benefit of compression even in the face of a reduced ABI measure.
"I think people get more harm from edema and are improved with gentle compression," Dr. Miller says. "It is better to reduce the edema."
Venous ulcers can present in uncommon locations, Dr. Miller notes. "We can see very atypical manifestations," he says. "Not all (venous ulcers) present in the classical distribution of the saphenous veins. Not all fit the text book picture. The venous system is complicated and there are many branches of the saphenous veins. A venous ulcer, for example, may present between the toes. To avoid misdiagnosis, we must be aware of atypical venous ulcer locations."
Some of the signs of venous ulcers include ankle/leg swelling, non-pitting edema, discoloration, venous eczema, and lymphedema.
Unfortunately, not much progress has been made in improving the healing rates and re-ulceration rates of ulcers even with advances in the management of ulcers, Dr. Miller says.
"Greater than 40 per cent of ulcers persist 12 months or longer and re-ulceration occurs in about 25 per cent of patients at one year," he says.
It is widely recognized that compression is an integral part of the management of venous ulcers.
"The bottom line is that every venous ulcer should be treated with uninterrupted compression until it is healed, so the ulcer is never out of compression until healed," Dr. Miller says. "Even large, circumferential ulcers will heal with consistent, repetitive compression therapy."
The "workhorse" of compression therapy is the Unna boot, named after dermatologist Paul Gerson Unna, which is made up of a low compression gauze bandage with 10% zinc oxide paste, gelatin, glycerin and water.
"At rest, this boot puts little pressure on the ulcer, but with movement, compression is achieved," Dr. Miller says. "We have many options among compression devices. A multi-layer compression bandage system, for example, Profore™, provides an option for continual compression during both rest and motion."
Frequency of dressing changes will be determined by the amount of drainage. As the drainage diminishes, the "boots" will be changed less frequently and usually stay in place for weekly intervals. Too frequent changing of dressings can traumatize wounds and impair the re-epithelialization which is necessary for proper healing, Dr. Miller says.
There is no optimal dressing for all stages of healing, and the selection of dressings is sometimes driven by what is currently in vogue. Remember that the underlying principle for healing is moist wound care, Dr. Miller says.
Since the healing process is fragile, clinicians need to eliminate impediments to healing such as trauma, pressure, friction, edema and necrotic or infected tissue.
"If you constantly change dressings or traumatize the wounds, you will interrupt and destroy the re-epithelialization," Dr. Miller cautions.
Debridement of a venous ulcer does not need to be complicated, Dr. Miller says. Tools of choice include sharp scissors and a curette.
"You have to get rid of biofilm, and the best way to get rid of it is with a curette and/or scissors," he says. "You can also achieve autolysis with Duoderm™, a hydrocolloid dressing."
When patients have diabetes and are neuropathic, local anesthetic is not necessary to debride an ulcer. If patients have sensation, a topical or intralesional anesthetic will likely be needed to reduce pain, Dr. Miller says.
"Debride, off load, and keep the wound moist," Dr. Miller says, suggesting petrolatum jelly can be applied to retain moisture. "You can heal every one of the neuropathic ulcers. The most difficult to heal are those on the plantar surface where offloading can be best achieved with a total contact cast."
The application of antibiotic cream or ointment to maintain moisture is no longer indicated because of reported allergic and even anaphylactic reactions, he notes.
As a rule, compression stockings should continue to be worn after an ulcer has healed, and it is vital that stockings be worn throughout the day, Dr. Miller advises. Such a measure will help to avoid re-ulceration.
"Stockings should be removed at bedtime and re-applied immediately upon awakening," he adds. "Don't get up and move around and eat breakfast. At that point, you can already have swelling. It may be difficult to get the stockings on, and it will be more difficult to eliminate the edema."
Application of compression stockings can be a challenge for a segment of patients, such as those who are elderly, arthritic or obese. An alternative for compression might be a multi-purpose bandage, for example Tubigrip™, which can be easily donned and removed, Dr. Miller says.
Why don't wounds heal? Look for other diagnoses, for example, skin cancer, unusual infections or pyoderma gangrenosum. "The list is long," he says.
In Dr. Miller's experience, peristomal ulcerations often represent erosive pustular dermatosis which responds to debridement and topical steroids. In
Another clinical pearl that Dr. Miller offers is that intralesional triamcinolone can effectively manage lipodermatosclerosis.1J Am Acad Dermatol. 2006 Jul;55(1):166-8.
Campbell LB, Miller OF 3rd. Intralesional triamcinolone in the management of lipodermatosclerosis. J Am Acad Dermatology. 2006;55(1):166-68.