Compression therapy for venous leg ulcers

INTRODUCTION

Compression therapy is the mainstay of treatment of venous leg ulcers (VLU). Good wound care and compression therapy will heal majority of small venous ulcers of short duration.[1] Goals of compression therapy are ulcer healing, reduction of pain and edema, and prevention of recurrence.[2] Compression is used for VLU and narrows veins and restores valve competence and reduces ambulatory venous pressure, thus reducing venous reflux (VR). It also helps decrease inflammatory cytokines, accelerates capillary flow, and lowers capillary fluid leakage thereby alleviating limb edema. It also softens lipodermatosclerosis, improves lymphatic flow and function, and enhances fibrinolysis.[3]

Indications

The aim of compression therapy is to improve the venous function without compromising arterial function.

Contraindications

The contraindications of compression therapy are the following[4,5]

• Advanced peripheral obstructive arterial disease (ankle brachial pressure index [ABPI] <0.8) (Evidence level A)

• Systemic arterial pressure <80 mm Hg at ankle

• Phlegmasia cerulea dolens

• Uncontrolled congestive heart failure

• Abscesses

• Septic phlebitis

• Advanced peripheral neuropathy.

CLASSIFICATION

Compression can be broadly divided into bandages and compression stockings. The details are mentioned in Table 1.[6,7] The compression bandages can be classified as inelastic (short stretch bandages [SSB]) and elastic (long stretch bandages [LSB]). The differences between the two groups of bandages are elucidated in Table 2.

Table 1.

Types of compression therapy

Table 2.

Comparison between elastic (LSB) and inelastic compression bandages (SSB)

COMPRESSION BANDAGES

All bandages used in compression must be applied on top of padding (subcompression wadding bandage) to prevent friction and pressure damage over bony prominences by spreading pressure across a greater area. Bandages should generally be applied toe to knee at 50% stretch and with 50% overlap but specific manufacturer's instructions should be followed for each bandage. Interface pressure peaks on the leg during walking exceeding 50-60 mm Hg reduce VR and increase venous pumping function. This may be achieved by stiff compression textiles like multicomponent bandages, especially when containing cohesive material or by zinc paste bandages. These compression types exert high stiffness which is characterized by a tolerable resting pressure and high pressure peaks during walking (“working pressure”), but need to be applied by well trained and experienced staff. Short stretch adjustable Velcro-wraps and (double) compression stockings may be promising alternatives allowing self-management.

INTERMITTENT PNEUMATIC COMPRESSION

Intermittent pneumatic compression constitutes inflating and deflating an airtight bag worn around leg. IPC controls edema in case compression bandage and stocking has failed. IPC upon compression therapy may accelerate ulcer healing.[8] It is particularly useful in patients with restricted mobility and when concomitant arterial disease is detected, where it helps reduce edema and enhance arterial blood flow.[9,10] IPC may improvement in hematologic, hemodynamic and endothelial effects which explains its role in healing of VLU.[11]

HEAD TO HEAD COMPARISON BETWEEN VARIOUS MODALITIES OF COMPRESSION

Compression versus no compression/usual care/simple dressings

Various guidelines have recommended that some compression is better than no compression[12,13] (evidence level A). A Cochrane review in 2009[4] (evidence level A) compared compression with either primary dressing, noncompressive bandages and usual care that always did not include compression and concluded that venous ulcers healed faster with compression and some form of compression is better than no compression in healing VLU.

High compression versus low compression

High compression bandages provide and maintain high levels of compression pressures in the range 25-35 mm Hg at the ankle. High compression is useful for bigger legs or more active patients. They can be used over padding on their own or as part of a layered system, and should be applied in a spiral according to manufacturer's instructions. Evidence exists that high compression is better than low compression in managing VLU[4,12,13,14,15] (evidence level A).

Single component versus multicomponent bandage systems and single layer versus multilayer

Studies have emphasized the fact that multi-layering increases stiffness of bandages and increases sub bandage pressure (SBP), thereby being inelastic practically. It ensures even distribution of SBP[4,12,16] (evidence level A). SBP of 30-40 mm Hg is recommended for healing of VLU (level of evidence A). Multicomponent multilayered compression is superior to a single component, single layer compression bandage systems.

Inelastic versus elastic bandages (long stretch bandages vs. short stretch bandages)

Two studies[17,18] demonstrated superiority of inelastic bandages in healing venous ulcers and reducing VR over elastic bandages. Short stretch compression (inelastic) and Unna's boot was found to support the pump function better than a long stretch compression (elastic)[19,20] (evidence level A).

Compression stockings

Use of a Class I or II stocking in patients with chronic venous insufficiency (CVI) led to reduction in the lower leg volume of 55-70 ml[14] (evidence level C).

Stockings (single layer/two-layer) versus bandages

A Cochrane review[4] identified two trials of compression bandages versus single layer compression stocking. No difference was detected among single layer stocking when compared to paste based bandages (Evidence level A). However healing outcome was better when a two layered stocking was compared to SSB (evidence level A). A meta-analysis of eight heterogenous randomized-controlled clinical trials (RCTs) concluded that stockings are better than compression bandages. There was better impact on pain, quicker healing by 3 weeks and increased ease of use with stockings[21] (level of evidence B). Pain scores were better for compression stockings than compression bandages[4,22] (level of evidence A). A well-chosen and correctly calibrated compression stocking exerting a pressure of 35 mm Hg or more is a good alternative to bandages in healing VLU[23,24] (level of evidence B).

Compression and surgery

Multiple sources and studies have shown that selective compression enhances sclerotherapy results[25,26] (level of evidence B). A RCT compared subfascial endoscopic perforator surgery with ambulatory compression and concluded that healing rates and recurrence rates in both modalities of treatment were same. However, the study recommended a combination of both for optimal results[27] (level of evidence B).

Intermittent pneumatic compression with or without compression versus compression alone

Berliner et al.[28] (evidence level A) reviewed eight studies, three of which showed that compression pumps could alleviate symptoms of CVI and assist with the healing of longstanding chronic ulcerations. A systematic Cochrane review identified four trials of IPC + Compression versus compression alone (Unnas boot/four layer dressing/stockings)[29] (evidence level A). Only one trial showed lesser time to heal and increased rate of reduction in ulcer area, although it could not identify any difference in ulcer healing between the two groups. Further studies are required to assess the status of IPC as alternative/adjuvant to compression and to optimize cycle times and IPC duration per day to effectively heal VLU.

Compression therapy modification in peripheral arterial disease

In patients with arterial occlusive disease (ABPI 0.6-0.8) modified compression using stiff material applied with reduced pressure (<40 mm Hg) under careful control may increase both arterial flow and venous pumping function. Compression decreases the elevated pressure within the venous system and may also increase arterial blood flow according to recent data in patients with mixed ulcers[30,31,32,33,34,35], (evidence level B).

Drawbacks of compression therapy

• Correct application of compression bandages need expertise

• Older debilitated patients with comorbidities find it difficult to use compression stockings

• Peripheral vascular compromise in patients with mixed-arterial venous ulcers with low ABPI

• Reduced compliance due to wearer discomfort.

CONCLUSION

Compression therapy is a highly effective treatment for VLU. Care should be taken while administering this therapeutic modality in case of mixed-arteriovenous ulcers. The minimum tolerable compression pressure tailored to the patient's requirement should be ensured so as to maximize compliance.