Blood Flow Stimulation in the Lower Limbs by Application of Different External Devices

Karolinska University Hospital

Status: Completed

Conditions: Deep Vein Thrombosis; Venous Stasis

Treatments: Device: Slow calf IPC; Device: Rapid calf IPC; Device: Foot IPC; Device: Calf NMES

Study type: Interventional

Funder types: Other

Identifiers

NCT03420625

SW2016-17-HEMOD

Details and patient eligibility

About

In this study, four different devices which stimulate the blood in the lower extremities are used in ten healthy persons while measuring the blood flow with ultrasound. The aim is to study the haemodynamic effects in the lower extremities of each modality and also to compare those effects between the four modalities in order to identify those which most effective than the others.

Full description

Three Intermittent Pneumatic Compression (IPC) devices were selected: Foot-IPC, rapid Calf-IPC and a slow, sequential Calf-IPC. A Neuromuscular Electrical Stimulation (NMES) device was also used in the calf. Blood flow measurements in the right popliteal vein of ten healthy individuals were performed using Doppler ultrasound before (control) and while using IPC or NMES. The blood flow parameters measured where: peak systolic velocity (cm/s), time-averaged mean velocity (cm/sec), volume flow (ml/min) and ejected volume per individual stimulus (ml). The tolerability of each device was also assessed using an analogue scale from zero to ten. Differences between modalities regarding the pattern as well as the absolute values of velocity and volume are being assessed. Power calculation: Recent studies showed that the peak venous velocity (PV) at baseline is around 11 cm/s and after applying foot-IPC the PV rises to 50 cm/s with a maximum standard deviation of 15 (Broderick et all, 2014). Thus, three patients per group would be required to detect a difference of 39 cm/s in PV (two-sided type-I error rate = 5%; power = 80%). To reach an even higher power we choose to include 10 patients in study, which resulted in a power of 99.7% for the above calculation.

Enrollment: 10 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Healthy volunteers

Exclusion criteria

• pregnancy
• previous lower limb operation involving the vascular system
• current thromboprophylactic or thrombolytic therapy
• vascular abnormalities in the lower limbs
• cardiorespiratory or renal failure causing pitting oedema

Trial design

Primary purpose: Supportive Care

Allocation: Non-Randomized

Interventional model: Crossover Assignment

Masking: None (Open label)

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10 participants in 4 patient groups

Foot IPC

Active Comparator group

Description:

Intermittent pneumatic compression in the foot using the A-V Impulse™, Covidien®, New Haven, CT, USA

Treatment:

Device: Foot IPC

Rapid calf IPC

Active Comparator group

Description:

Intermittent pneumatic compression in the calf using the VenaFlow® Elite, DJO Global, USA

Treatment:

Device: Rapid calf IPC

Slow calf IPC

Active Comparator group

Description:

Intermittent pneumatic compression in the calf using the Kendall SCD™ 700, Covidien, Medtronic, USA

Treatment:

Device: Slow calf IPC

Calf NMES

Active Comparator group

Description:

Neuromuscular electrical stimulation in the calf using the DJO,TM, CefarCompex Mi-Theta 500 stimulator

Treatment:

Device: Calf NMES