Evaluation in 15 Participants of Blood Flow, Comfort and Efficiency, Using 1 vs 36 Hz Stimulation Via Textile Electrodes

Study Overview
=================
Brief Summary
-----------------
Muscle contractions induced by calf low-intensity neuromuscular electrical stimulation (C-LI-NMES) can increase venous return and may reduce venous thromboembolism. This study aimed to compare the effect of different C-LI-NMES frequencies and plateau times on hemodynamics, discomfort and energy efficiency, when applied via sock-integrated transverse textile electrodes.

Detailed Description
-----------------
Fifteen healthy participants were stimulated via two 3x3cm transverse textile electrodes integrated in a sock, with ten different combinations of frequency (1Hz or 36Hz) and plateau times (0.5/1.5/3/5/7s), with gradually increasing NMES-intensity until plantar flexion-induction. At this point, popliteal peak venous velocity (PVV), time-averaged mean velocity (TAMV) and ejection volume (EV) were assessed by Doppler-ultrasound, discomfort by a numerical rating scale (NRS, 0-10) and values for current amplitude and energy were calculated based on the NMES-device´s intensity level. Values expressed with median (interquartile range), significance set to p<0.05.

Official Title
-----------------
Can Blood Flow Enhancing Plantar Flexion Electrically Induced Via Textile Electrodes in a Sock Using 1 Hz Frequency Give Better Comfort and Energy Efficiency as Compared to 36 Hz ?

Conditions
-----------------
Hemodynamic Instability, Pain

Intervention / Treatment
-----------------
* Device: Chattanooga Physio, DJO, neuromuscular electrical stimulation


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Age 18-99 years of age Voluntary participation Exclusion Criteria: Pregnancy Pacemaker Ongoing thromboprophylaxis Skin wounds Vascular abnormalities Previous vascular system surgery in the lower limbs

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 99 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Intervention Model: Sequential Assignment
Interventional Model Description: Repeated measures tests on on each of the 15 participants, comparing outcomes for no intervention and 10 different interventions in the form of variations in parameter-settings of neuromuscular electrical stimulation, with gradually increasing current amplitude until induction of ankle plantar flexion.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Single arm where repeated measures where performed in 15 participants.<br>Each of the 15 participants in the arm was, in addition to the resting state (no intervention), exposed to 10 different interventions repeated after each other to enable repeated measures of the outcomes. | Device: Chattanooga Physio, DJO, neuromuscular electrical stimulation<br>* Neuromuscular electrical stimulation (NMES) was applied with a device called Chattanooga Physio (DJO), testing 10 different combinations of parameter-settings. The parameter-settings that were varied and combined were frequency (1Hz and 36Hz) and plateau times (0.5s, 1.5s, 3s, 5s, 7s). The NMES was applied to the calf of the participants via transversally placed textile electrodes (3x3 cm) integrated in a sock starting with very low current amplitude followed by gradual small increases in current amplitude until induction of ankle plantar flexion, at which time-point the outcomes where measured.<br>* Other names: Device name and manufacturer:;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Peak venous velocity (PVV) | Peak venous velocity (centimeters per second) will be assesed by Doppler ultrasound of in the popliteal vein | Day 1 at rest (baseline, no intervention) and when ankle plantar flexion was induced by the intervention | 
| Time averaged mean velocity (TAMV) | Time averaged mean velocity will be assesed by Doppler ultrasound in the popliteal vein (centimeters per second) | Day 1 at rest (baseline, no intervention) and when ankle plantar flexion was induced by the intervention | 
| Average duration of blood pulse (ADBP) | Average duration of blood pulse will be assesed by Doppler ultrasound in the popliteal vein (seconds) | Day 1 at rest (baseline, no intervention) and when ankle plantar flexion was induced by the intervention | 
| Ejection volume (EV) | Ejection volume of blood will be assesed by Doppler ultrasound in the popliteal vein (milliliters) | Day 1 at rest (baseline, no intervention) and when ankle plantar flexion was induced by the intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Numerical rating scale (NRS) | Discomfort estimated using a numerical rating scale from 0 (no pain) to 10 (worst pain) | Day 1 during ankle plantar flexion was induced by the intervention | 
| Current amplitude | Current amplitude in milliampere (mA) will be assessed by using stepwise increases (typically 1mA) on the NMES device until a plantar flexion is induced | Day 1 during ankle plantar flexion was induced by the intervention | 
| Energy | Energy per stimulation cycle in millijoule (mJ) will be assessed by using stepwise increases (typically 1mA) on the NMES device until a plantar flexion is induced, at which point the energy consumption (mJ) is calculated. | Day 1 during ankle plantar flexion was induced by the intervention | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Neuromuscular electrical stimulation, Hemodynamics, Physical inactivity