Giovanni Mosti1 and Attilio Cavezzi2. Phebology 2019

Main findings

• Few papers specifically dedicated to compression therapy in lymphedema. Moreover, many studies on compression therapy are burdened with several methodological flaws and confounding factors making hard to accept even the little data we have.
• The lack of consistent data is the main reason why we do not have solid recommendations in compression therapy of lymphedema, especially regarding the compression pressure to apply and stiffness of materials.
• Up to a decade ago, best practice was still based on a compression where “the optimal sub-bandage pressures for the multi-layered lymphatic bandage systems (MLLB) used in lymphedema have yet to be determined”.
• The static stiffness index (SSI) is calculated by subtracting the supine interface pressure from the standing pressure in the medial gaiter area where the tendinous part of the gastrocnemius muscle turns into its muscular part (named point B1). It was proven that the SSI is able to discriminate between the elastic (SSI<10) and inelastic (SS>10) compression devices.
• Low pressure is more effective and better tolerated than a strong pressure to treat arm lymphedema and this is true both after 2 and after 24h. This is likely due to the different filtration pressure that is much higher in the leg than in the arm in the standing and sitting position. The possible impaired lymph drainage caused by higher pressures is another proposed explanation.
• Similar outcomes concerning the efficacy/ compliance issue of compression in breast-cancer-related lymphedema were highlighted in a recent study, where elastic garments with presumably lower pressure compared to bandages achieved about the same outcomes, but elastic garments were much better tolerated both at 10 days and 3 months (p=0.065 at three months).
• When treating venous oedema and dependency syndrome (soft, pitting oedema that disappears or reduces in supine position), we were able to show that a stocking exerting around 20mm Hg pressure at the ankle is almost as effective as an inelastic bandage exerting a pressure higher than 60 mmHg. In the author’s experience, an optimal compression pressure in leg venous oedema was around 40mmHg at the ankle, especially when maintained overtime by means of an adjustable compression device.
• It was demonstrated that adjustable compression wraps, even when applied with the same pressure of about 50 mm Hg as inelastic bandages, are more effective in leg volume reduction due to the device self-readjustment by patients leading to a better pressure maintenance overtime.
• In leg lymphedema, experimental studies (performed through intra-lymphatic pressure and flow measurement), the gradual increase of foot-applied compression up to 40 mmHg, showed an increasing intra-lymphatic pressure while evoking spontaneous lymph vessel contractions. Higher pressures did not result in any additional beneficial effect.40 In agreement with literature data, a pressure of about 40–50 mm Hg has been established as a standard value in increasing the lymph drainage in the lower limb: higher pressure is not necessary and potentially counterproductive.
• Despite suggestions regarding compression with high stiffness to treat lymphedema, our group showed that elastic stockings exerting 23–32 mm Hg, as well as elastic kits exerting about 40 mm Hg, were almost as effective as inelastic bandages in reducing the lower limb oedema.
• The average SSI value of these compression devices was 3 both for elastic stockings and elastic kits. Similarly, ACW static stiffness index value was 7 in our study38 on venous oedema and 2 in the lower limb lymphedema study, both indicating a low stiffness of the material. In contrast, inelastic material had always an SSI value higher than 10 and also above 20, but this high stiffness did not result in a more effective oedema treatment.
• It is necessary to underline that both elastic stockings and ACW maintained their pressure range overtime very effectively in all these studies, whereas inelastic bandages showed a significant pressure loss already after 24 h.
• Regarding the comfort of compression devices, inelastic bandages are always reported as comfortable in the examined studies. Both elastic stockings and elastic kits were well tolerated during the day and not well tolerated only overnight. ACWs applied in lymphedema treatment were reported to have a good comfort without any complaint from the patients and without significant differences compared to inelastic bandages.
• It is important to note that elastic garments were compared to bandages it would have been also useful to compare a variety of compression garments with different levels of stiffness such as flat knit garments.