The use of a novel in-bed active Leg Exercise Apparatus (LEX) for increasing venous blood flow

Abstract

Objective: The incidence of pulmonary embolism (PE) and leg deep vein thrombosis (DVT) has increased in recent years in association with aging and an increase in the number of bedridden individuals. We developed an active in-bed leg exercise apparatus labeled the Leg Exercise Apparatus (LEX) for DVT prevention. We compared the effect of leg exercises performed using the LEX to conventional active ankle exercises on increased blood flow.Materials & Methods: The subjects were eight healthy adult volunteers [five men and three women, aged 20–34 (mean 27.0) years]. Subjects performed two types of exercise; exercise 1 consisted of leg exercises using the LEX, while exercise 2 consisted of in-bed active plantar flexion/dorsiflexion exercises without the device. Measurements were taken 1, 5, 10, 20, and 30 minutes after exercise including common femoral vein blood flow, mean blood flow velocity, maximum blood flow velocity, and vessel diameter using Doppler ultrasound. Statistical procedures included timed measurement data analysis using a linear mixed model. A Bonferroni correction was used for multiple comparisons.Results: Compared to resting levels, blood flow reached a maximum value 1 minute after exercise for both exercise types, with a significantly greater increase after exercise 1 (1.76-fold increase) compared to exercise 2 (1.44-fold increase) (p = 0.005). There was a significant difference (p = 0.03) between the two exercises for all values from 1 minute to 30 minutes following exercise. There was no significant difference between exercises for peak or mean blood flow velocity. Compared to resting levels, blood vessel diameter reached a maximum value of 1.47-fold greater at 5 minutes post-exercise for exercise 1 and a maximum value of 1.21-fold greater at 1 minute post-exercise for exercise 2.Conclusions: Exercise using the LEX increased lower leg venous blood flow and vessel diameter. We propose that the LEX may serve as a new DVT prevention tool.

A novel exercise device for venous thromboembolism prophylaxis improves venous flow in bed versus ankle movement exercises in healthy volunteers

“…Another study compared femoral venous flow in healthy participants for a period of 30 min after 1 min of exercise, at a rate of 30 cycles/min, with and without LEX. 20 After 1 min of exercise with LEX, the venous flow volume and vessel diameter at 30 min was higher than that observed at 30 min, after 1 min of exercise without LEX, in the same leg.…”

“…24 All ultrasound examinations were performed by an experienced cardiologist using the EUB 7500 (Hitachi, Tokyo, Japan) and a 5-13-MHz linear array ultrasound transducer. Environmental conditions were maintained at a temperature of approximately 20 C and a relative humidity of 50-60%.…”

“…The LEX is designed to be used in the supine position, specifically for postoperative and bedridden patients. [18][19][20][21] We previously reported that a short period of active ankle exercise with the LEX improved femoral venous flow volume compared to continuous intermittent pneumatic compression. 18 The LEX makes combined leg motion possible, which involves ankle dorsiflexion/plantar flexion, ankle inversion/eversion, and knee and hip flexion/ extension.…”

Analysis of risk factors for deep venous thrombosis in patients with gynecological malignant tumor: A clinical study

“…In a retrospective study of consecutive patients undergoing total hip arthroplasty, 126 patients underwent manual calf massage and passive ankle motion, and 138 patients underwent total hip arthroplasty using the same surgical approach without this mechanical prophylaxis, Imai and colleagues found the incidence of deep vein thrombosis was 6.52% and 0.79% in the control and rehabilitation groups, respectively, indicating performing this mechanical prophylaxis reduced the incidence of venous thromboembolism after total hip arthroplasty 20. Many reports showed an increase in femoral vein blood flow during active ankle exercises21, which lead to a reduced rate of DVT in the rehabilitation group. In the current study, although the included patients were different, but the mechanism of rehabilitation exercises for prevention of DVT are identical.…”

Regular Physical Activity and Risk of Venous Thromboembolism

“…However, increased venous flow has been recorded up to 30 minutes after exercise cessation. 58 Moreover, in subjects with venous insufficiency, a 6-month exercise program with focus on calf muscle strength improved the calf muscle pump function. 59 In addition, higher resting blood flow in femoral arteries has been reported in trained compared with untrained individuals.…”