Leg Ulcer Evaluation and Treatment Principles
- Patient and wound assessment
- Pathophysiology of chronic venous insufficiency
- Noninvasive vascular assessment
- Segmental pressure recordings
- Duplex ultrasonography
- Recommendations for treatment (compression)
- Dressing selection and education
- Treatment of mobile and immobile patients
- Outcome analysis
Accurate assessment is the key to effective leg ulcer management. Venous stasis ulcers, ischemia diabetic complications are responsible for over 90% of leg ulcers.
Venous stasis ulcers affect 1 to 2% of the population. The cost of management of leg ulcers has been estimated to be:
- Scandinavia – $25 million (1985 U.S. dollars)
- United Kingdom – $200 Million (1989 U.S. dollars)
- United States – Projected $1 Billion
The impact on quality of life is immeasurable but includes pain, decreased mobility, negative self-image, and feelings of anger, fear, isolation and depression.1,2
An initial assessment of the patient with an ulcer of the lower extremity must include a detailed patient history, which will provide clues as to the differential diagnosis. Careful physical examination is necessary to evaluate the size and characteristics of the wound and should highlight any associated medical conditions. This should also include evaluation of the patient’s social circumstances as these may impact on both care and healing.3
A Recommended Management Pathway for Leg Ulcers
The International Leg Ulcer Advisory Board comprises some of the most eminent clinicians and researchers in the field from Europe, North America and Australia. The panel designed a recommended management algorithm based on a review of the available literature and expert consensus and also looked at relevant conferences and existing guidelines when making their decision about the algorithm. The International Leg Ulcer Advisory Board Published their review in the Journal of the European Wound Management Association, May 2002.4
In order to ensure ease of use and effectiveness, the algorithm has been kept as simple and straightforward as possible. The algorithm can be broken down into four stages: Assessment, Diagnosis, Recommendations for Treatment and Outcomes:[swf src=”https://www.cardiachealth.org/wp-content/uploads/2015/12/module5_figure_1.swf” width=700 height=500]
Review a patient’s history:
- Previous history of deep vein thrombosis or venous ulcer
- History of leg edema
- Cause of the wound such as trauma or pressure
- Treatment history of the wound to date
- Wound duration: acute ( 6 weeks)
- Identification of systemic factors that affect wound healing (medications, acute and chronic illnesses, age etc)
- Nutritional status
- History of travel or known exposure to fungal or parasitic causes
Investigating and obtaining a thorough patient history will help in identifying the correct cause and facilitate management.
A complete wound assessment consists of a careful evaluation of the wound and surrounding tissue. Components of the wound assessment include:
- Location of the wound
- Physical characteristics of the wound including size and depth of injury
- Presence of undermining, tunneling, sinus tracts, foreign bodies and exposed bone
- Appearance of the wound bed
- Skin color and condition
- Skin temperature
- Amount and characteristics of exudate
- Presence of local or general edema
- Presence and nature of pain
Pathophysiology of Chronic Venous Insufficiency
Normal Venous Return
Normal venous return is the result of two mechanisms. First the calf pump during ambulation: the calf muscle contracts and compresses the venous compartment, which propels blood in the veins up towards the heart.
The one way valves open when the calf muscle contracts and close when the calf muscle relaxes and this prevents the reflux of blood and distention of the veins.
Pathogenesis of Venous Ulcers
Definition: The basic physiologic abnormality underlying the manifestations of “Chronic Venous Insufficiency” is an elevation of ambulatory venous pressure.
|Valvular incompetence within the perforating veins
connecting superficial and deep veins
Ambulatory Venous Hypertension
Failure of the venous pressure to decrease during ambulation
Capillary distention and increased permeability of large molecules into the skin
Venous Ulceration Assessment
The pathogenesis of venous ulcers is the focus of much research. It is generally agreed that venous hypertension is the fundamental problem. There are several hypotheses that have emerged to explain the formation of venous ulcers. Venous hypertension is often the result of valvular incompetence secondary to Deep Vein Thrombosis. As a DVT forms, the thrombus adheres to the endothelium, contracts and scarring destroys the valves. Recanalization of the vessel leaves high resistance incompetent channels.
It has been suggested that venous hypertension leads to the distention of vessels causing an increased permeability of the vessel wall resulting in the leakage of large molecules or blood components into the skin. It is the presence of these components that interferes with the diffusion of oxygen and the delivery of nutrients to the skin. One hypothesis suggests that it is the presence of fibrin, which forms pericapillary fibrin cuffs, which impedes the diffusion of oxygen and nutrients between the blood vessel and the dermis. This results in anoxia leading to ulceration. While this hypothesis has some merit, a number of flaws have been identified.
Another hypothesis suggests that white blood cells can become entrapped in areas of reduced venous flow adhering to endothelium, causing occlusion of the capillaries and damage to dermal vasculature releasing fluid and inflammatory mediators into the tissue leading to chronic inflammation.
The following animation will assist the learner in understanding venous blood flow and the pathogenesis of ulceration.
|Non-Invasive Vascular Assessment
An accurate vascular assessment of the extremity is necessary to ensure that the correct etiology of the ulceration has been identified and to exclude those patients with arterial disease for whom compression is dangerous. There are a number of non-invasive methods used to confirm venous disease when a patient presents with suspected venous ulceration. Methods of assessment include:Examination of:
Doppler Assessment and Ankle Brachial Index
The Doppler is a vital tool of assessment when trying to determine the underlying etiology of leg ulcers and determine a course of treatment that will maximize wound healing potential. Predominantly leg ulceration is of venous origin and requires sustained compression to facilitate venous return from the lower extremities. However, before any type of compression management can be considered, a Doppler test should be performed to determine whether there is arterial involvement or whether the ulcer is the direct cause of arterial compromise. The significance of assessing for adequate arterial flow in the affected extremity is of utmost importance as the application of compression to an ulcer of arterial or mixed etiology could further compromise blood flow and result in ischemia.
The following exercise will assist the learner in developing the skills necessary to locate pulses and differentiate arterial and venous sounds of the arms and lower extremities. Followed by an explanation of the procedure.
Ankle Brachial Index Procedure
Recording Ankle Brachial Index (ABI) also known as Ankle Brachial Pressure Index (ABPI) or Resting Pressure Index (RPI)
ABI Clinical Significance
1.2 may represent a falsely elevated ABI, which can result in patients with sclerotic vessels for example patients with Diabetes or Renal Failure. The blood vessels become stiff and ridged and are not readily compressible leading to falsely elevated reading. These patients may require further vascular testing to determine adequacy of perfusion.
It is important to periodically repeat the ABI to monitor progression of disease. A decrease of more than 0.2 is consistent with a decrease in perfusion and progression of disease.
|Segmental Pressure RecordingsIn this examination, systolic pressures are measured sequentially up the leg from ankle to thigh. A pressure difference of greater than 25 mmHg between levels indicates occlusive disease.
Duplex Ultrasonography measures blood flow velocity through a vessel and is the primary method of identifying venous obstruction or abnormal venous reflux
A number of plethysmographic methods, including air and photo plethysmography, may be used to assess venous function. Other investigations may also take place to exclude disorders such as rheumatoid arthritis, diabetes, renal failure, anemia, tumors and auto-immune disorders.
A comprehensive physical exam can provide important information for the differential diagnosis of venous disease. It is essential to determine the adequacy of arterial perfusion because compression therapy is the gold standard of treatment for venous ulcers and high level compression is contraindicated in the presence of arterial disease with an ABI of less than 0.8. Reduced levels of compression are recommended in the case of mixed etiology ulceration with an ABI 0.6 – 0.8 mm Hg.
Hyperpigmentation CVI leads to distension of the blood capillaries and damage to the endothelium, leading to leakage of red blood cells. The breakdown products of hemoglobin cause dark staining of the skin or hemosiderosis.
Lipodermatosclerosis may be described as “woody” induration of the tissues with fat replaced by fibrosis. The leg often assumes an inverted champagne bottle shape.
Edema Venous pressures and increased capillary permeability can lead to increased interstitial fluid. Venous disease can also be complicated by poor lymphatic drainage. Characteristically edema associated with CVI may involve the lower leg and foot, is considered pitting edema and will occur in one or both legs depending on the extent of the venous disease.
Venous dermatitis and eczematous changes These are often associated with CVI and can be aggravated by wound care products through irritation and allergy. Persistent scratching may cause secondary infections.
Ankle flare refers to the collection of small venular channels inferior to the medial malleolous and extending onto the medial surface of the foot. This sign is indicative of CVI.
Venous Ulcer Characteristics
Recommendations for Treatment
There are fundamental principles for developing a comprehensive management plan for the patient with CVI and /or venous ulcers.
Compression therapy is the gold standard for treatment of venous ulcers. It is extremely difficult for venous ulcers to heal in absence of compression. There are a variety of interventions for providing compression, however not all have the same level of effectiveness.
Sustained compression provides the mainstay of treatment in venous leg ulcers. This should be supported with adjunctive medical and surgical therapy, appropriate dressings and patient education. Sustained compression is provided by multi-layer elastic or inelastic bandage systems. There is now considerable evidence to show that this form of sustained high compression improves ulcer healing and provides quality of life and cost benefits. Multi-layer high compression bandaging improves healing of venous leg ulcers when compared with single layer, low compression bandaging although there is little reliable evidence to date of large randomised controlled trials which directly compare 4-layer compression to 3-layer or 2-layer bandaging.
Multi-layer bandage systems are complemented by reduced compression systems (15-25 mmHg) for those patients who cannot tolerate high compression systems, and compression stockings. Intermittent pneumatic compression (IPC) is a useful adjunct to multi-layer compression and has been shown to improve ulcer-healing rates when used with multi-layer compression.
The degree of compression produced by any bandage system over time is determined by complex interactions between four principle factors – the physical structure of the elastomeric properties of the bandage, the size and shape of the limb to which it is applied, the skill and technique of the bandager and the nature of any physical activity undertaken by the patient.
Laplace’s Law (Determining Sub-Bandage Pressure) – The pressure generated by a bandage immediately following application is determined principally by the tension of the fabric, the number of layers applied, and the degree of curvature of the limb. P=T/R
Applied pressure is directly proportional to the tension in a bandage (P increases with T) but inversely proportional (P decreases as R increases) to the radius of the curvature of the limb to which it is applied.
Methods of Compression
- Elastic compression (long-stretch) bandages exert high compression during rest and exercise whereas
- Inelastic (short-stretch) bandages produce passive compression mainly when the calf muscle contracts, increases in volume and creates pressure against the bandage. At rest, inelastic compression bandages exert pressure dependent on the tension used during application.
- Sustained compression – Any bandaging system providing sustained compression for at least one week (More frequent dressing changes may be needed if the wound is large and/or heavily exuding)
- Multi-layered (elastic) compression – Currently presented as 4-layer high compression bandaging providing sustained, graduated compression (including bandages >50% extension and exerting pressure at rest). (N.B. There are substantial differences in systems depending on bandage characteristics).
- Multi-layered (inelastic) compression – Multi-layer inelastic bandaging (<50% extension and exerting pressure at rest dependent on the tension used during application)
- Reduced compression – Compression of 15-25 mm Hg using a 1- or 2-bandage layer system. Reduced compression stockings are a valuable alternative.
- Compression stockings – Ideally, compression hosiery that provides compression of 35-45 mm Hg, but if not tolerated 25-35 mm Hg. There remains no international consensus on definition of the different classes of compression hosiery.
- Intermittent pneumatic compression – one of a number of devices which surround the leg and can be inflated to provide short-term pressures up to a maximum of 100 mm Hg.
The following exercise is designed to help the learner understand the effect of bandaging on venous insufficiency in the lower extremity.
Recommendations for treatment
A number of adjunctive medical therapies, including pentoxifylline, are currently in use without unequivocal support in the literature. There is also increasing realization that chronic wounds, such as venous ulcers, benefit from an overall approach aimed at optimising the wound bed. This approach, termed wound bed preparation, includes a number of aspects critical to wound care, such as elimination of excessive exudate and bacterial burden, debridement [debridement includes elimination of necrotic tissue], angiogenesis and the formation of a wound matrix that promotes re-epithelialization.
There is emerging evidence that skin substitutes may be beneficial in the treatment of hard to heal venous leg ulcers (especially in those with duration >1 year) when used in conjunction with multi-layer compression bandaging.11,12 Other biological agents, such as growth factors and protease inhibitors are currently being evaluated for their efficacy in the management of venous leg ulcers. Many patients with leg ulcers suffer pain that can adversely affect quality of life and may influence speed of healing. Reduced compression should be used until pain and edema resolves and then high compression bandaging can be introduced. In most cases, appropriate dressings or oral analgesics can effectively manage pain although skin grafting may be required in cases of intractable pain.
Dressing Selection and Education
Appropriate dressing selection
Patients with leg ulcers are prone to contact sensitivity particularly from wool alcohols, topical neomycin, framycetin, cetylstearyl alcohols and rubber mixes which are present in many dressings, ointments and creams. Emphasis should be placed on allergen avoidance to allow optimal wound healing. However this remains a difficult management issue in individual patients.
Factors that encourage ulcer healing, such as improved nutritional status, diabetic control, appropriate bandage use and mobility, are dependent on patient involvement. Education to improve patient understanding of the condition will aid compliance to therapy.4
Treatment of mobile and immobile patients
Reduced mobility and reduced ankle function, as well as other factors such as ulcer size and duration, have been shown to independently affect healing rates. As inelastic bandages lose pressure when leg edema is reduced, multi-layer elastic compression is recommended as first-line therapy for immobile patients with venous leg ulcers. The incidence of venous leg ulcers increases with age, rising to 6% among the population aged over 80 years old: a high proportion of this age group suffer from some degree of immobility.
Addition of intermittent pneumatic compression is recommended as second-line therapy in these patients. Multi-layer compression (elastic or inelastic) is recommended as first-line therapy in mobile patients. Elastic stockings can be used as second-line therapy in mobile patients, particularly those that are young and working or who are unable or unwilling to tolerate multi-layered compression.4
The International Leg Ulcer Advisory Board recommend a definition of failure to heal as no reduction in ulcer size in 1 month. Patients with ulcers <10 cm2 who have failed to achieve complete healing in 3 months should be referred to a specialist for re-evaluation including diagnosis and re-assessment and evaluation for surgical correction of any venous abnormality. Patients with ulcers >10 cm2 are likely to take a long time to heal and skin grafting may be required. Following healing of the ulcer, steps must be taken to minimise the risk of recurrence by using compression hosiery and maintaining education and support to the patient. Control of oedema by elevation and use of compression hosiery for life may be required. Compression hosiery should be applied at the highest level of pressure subject to patient compliance and dexterity.4
The International Leg Ulcer Advisory Board’s recommended guidelines based on a comprehensive review of the literature and expert consensus, confirm the role of sustained compression (elastic and inelastic) as first-line therapy for venous leg ulcers. Reduced compression and compression hosiery are useful alternatives in those patients with additional arterial disease or who cannot tolerate multi-layer bandaging. Intermittent pneumatic compression is a valuable adjunctive therapy in the treatment of venous leg ulcers although there is a need for further evidence-based findings on these techniques. In addition there is a need for further randomised, controlled trials on the other medical and surgical therapies to be used in conjunction with compression therapy. It is hoped that the algorithm provides a useful working tool for primary care physicians and nurse practitioners to provide appropriate care based on the latest findings in the literature.
- Sustained multi-layer compression is confirmed as first-line therapy for venous leg ulcers
- Reduced compression and compression hosiery are useful alternatives
- IPC is a valuable adjunctive therapy
- A need for further RCTs on the other adjunctive therapies.4
Stacey M et al. The use of compression therapy in the treatment of venous leg ulcers: a recommended management pathway. EWMA Journal 2002.
- Phillips T, Stanton B, Provan A & Lew R. (1994). A study of the impact of leg ulcers on quality of life: Financial, social and psychologic implications. J Am Acad Dermatol;31:49-53
- Sibbald RG, Williamson D, Filanga V & Cherry G. (2001). Venous Leg Ulcers. In Krasner & Sibbald (Eds) Chronic Wound Care: A clinical source book for healthcare professionals (3rd Ed), (pp. 483-494). Wayne PA: HMP Communications.
- Franks,P.J., Winterberg, H. Moffatt, C.J. (2002) Health-related quality of life and pressure ulceration assessment in patients treated in the community. Wound Repair and Regeneration, 10(3), 133-40.
- Stacey M et al. The use of compression therapy in the treatment of venous leg ulcers: a recommended management pathway. EWMA Journal 2002.
- Fletcher A, Cullum N, Sheldon T. A systematic review of compression treatment for venous leg ulcers. BMJ 1997; 315: 576-80.
- Margolis DJ, Berlin JA, Strom BL. Risk factors associated with the failure of a venous leg ulcer to heal. Arch Dermatol 1999; 135: 920-926.
- Moffat CJ, O’Hare L. Ankle pulses are not sufficient to detect impaired arterial circulation in patients with leg ulcers. Journal of Wound Care 1995; 4 (3): 134-138.
- Nicolaides AN. Investigation of chronic venous insufficiency: a consensus statement. Circulation 2000;102:126-163.
- Palfreyman SJ, Lochiel R, Michaels JA. A systematic review of compression therapy for venous leg ulcers. Vascular Medicine 1998; 3: 301-313.