Article

Effect of leg elevation on healing, venous velocity and ambulatory venous pressure in venous ulceration

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Abstract

Objective: Current treatment of venous leg ulcers (VLU) includes four-layer bandaging, appropriate superficial venous surgery and leg elevation. The aims of this study were to: investigate a device designed to measure leg elevation; assess how long patients elevate; and to assess the effect of elevation on ulcer healing, femoral vein velocity (FVV) and popliteal vein cross-sectional area (PVCSA), and venous pressure. Patients and methods: A datalogger and accelerometer were manufactured to measure leg elevation. The device was validated in eight control subjects; elevation was measured in 24 patients with VLU. Ulcers were traced over six weeks in 29 patients and elevation measured to correlate healing with elevation. Ten patients and 10 controls underwent duplex measurement of FVV and PVCSA to measure flow in relation to posture; nine patients underwent measurement of venous pressure with postural changes. Non-parametric statistical analysis was used. Results: The datalogger accurately recorded all episodes of elevation. Median (range) elevation time was 53 (0–350) mins/24 h; correlation between ulcer healing and elevation was poor at 0.103 ( P=0.616, Spearman); change in posture from sitting to supine produced a significant increase in median (range) FVV from 11 (7–24) to 34 (22–66) in VLU ( P=0.005) and 15 (12–34) to 38 (16–69) in controls ( P=0.005, Wilcoxon). Change in posture from supine to 25 degrees elevation produced no change in FVV in either group ( P=0.173 in VLU, P=0.327 in controls, Wilcoxon). In VLU, sitting PVCSA was 1.07 (0.51–1.45) cm ² . Supine position significantly reduced the area to 0.46 (0.27–1.01) cm ² ( P=0.005, Wilcoxon). On elevation to 25°, PVCSA was further reduced to 0.28 (0.07–0.63) cm ² ( P=0.058, Wilcoxon). In controls, sitting PVCSA was 0.79 (0.31–1.56) cm ² , supine was reduced to 0.46 (0.27–1.09) cm ² ( P=0.047, Wilcoxon) and on elevation was reduced to 0.23 (0.10–0.44) cm ² ( P=0.005, Wilcoxon). Venous pressure standing was 99 (73–116) mmHg, reduced to 76 (53–113) mmHg on sitting ( P=0.084), and further reduced to 23 (7–36) mmHg supine ( P=0.008, Wilcoxon). Conclusions: Leg elevation in patients with VLU is poor but can be accurately measured. Elevation in the presence of compression may not improve ulcer healing. Postural changes of the leg can produce an increase in deep venous flow and a reduction in venous pressure.

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... Elevating the legs above heart level will reduce leg oedema as the blood flows back to the heart under gravity, resulting in improved venous return (Dix et al, 2005). As a result, patients should be encouraged to rest with their limb elevated for either 30 minutes daily or for 3-4 shorter periods during the day (Abade et al, 2007). ...
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... 7,21,22 CEAP C2 venous disease may be treated using various ablative and surgical procedures. However, CEAP C3 disease employs conservative methods of treatment such as compression stockings, 23 limb elevation, 24,25 and intermittent pneumatic compression. 26,27 NMES may be useful in Table 2. Limb volume in sham and test group pre-and post-stimulation at week 0 and week 6. ...
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... The keywords 'leg ulcer*' or 'venous ulcer*' or 'varicose ulcer*' or 'ulcus cruris' were combined with 'elevation' or 'leg elevation' or 'physical activity' or 'exercise*'. Based on title, abstract and relevance 12 articles were included (Abu-Own et al. 1994, Yang et al. 1999, Kan & Delis 2001, Wipke-Tevis et al. 2001, Ibegbuna et al. 2003, Dix et al. 2004, Padberg et al. 2004, Xia et al. 2004, Abadi et al. 2007, Davies et al. 2007. ...
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... n a sitting position legs are placed above hip-level and in a prone position above heart level. Heinen et al. (2004) conclude that elevating the leg above the heart for 10-30 degrees was beneficial for skin oxygenation without compression, but that high compression with leg elevation can have a negative effect on skin oxygenation and wound healing. Dix et al. (2005) used an accelerometer to measure how often patients elevated their legs and found poor correlation between ulcer healing and minutes of elevation. Heinen et al. (2004) suggest that the combination of high compression and leg elevation may not improve ulcer healing. Patients should receive instructions on leg elevation in accordance with ...
... 269,270 Others reported that in the presence of compression, there was no correlation between median leg elevation per 24 hours and percentage decrease in ulcer size. 265 Although still recommended, treatment cannot rely on this otherwise simple advice, because patient compliance is poor and ulcer recurrence is extremely common even after a period of prolonged hospitalization. 271,272 Finally, leg elevation has been used before bandages are applied and could also be used to reduce leg swelling before elastic stockings are fitted. ...
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