Smart Bioimpedance Device for the Assessment of Peripheral Muscles in Patients with COPD

Area of Science:

• Biomedical Engineering
• Pulmonology
• Medical Imaging

Background:

• Muscle dysfunction and atrophy are significant complications in Chronic Obstructive Pulmonary Disease (COPD).
• Current evaluation methods for peripheral muscles (e.g., quadriceps) include ultrasound imaging and strength testing.
• These methods are crucial for COPD diagnosis, prognosis, monitoring, and assessing therapeutic interventions.

Purpose of the Study:

• To introduce bioimpedance spectroscopy (BIS) as a cost-effective and user-friendly alternative for peripheral muscle evaluation in COPD.
• To validate BIS technology against established methods like ultrasound and strength tests for assessing the quadriceps muscle.
• To develop prediction equations for muscle properties using BIS parameters.

Main Methods:

• Adaptation of a laboratory bioimpedance spectroscopy prototype for segmental measurements of the quadriceps.
• Conducting a pseudo-randomized study with 33 COPD volunteers in a clinical setting.
• Correlating bioimpedance parameters with structural (ultrasound thickness) and functional (isometric strength) quadriceps muscle assessments.

Main Results:

• Demonstrated a significant correlation between bioimpedance Cole model parameters and quadriceps muscle properties.
• Achieved a correlation of 0.69 for muscle thickness estimation with an average error < 0.2 cm compared to ultrasound.
• Obtained a correlation of 0.77 for isometric strength estimation with an average error of 3.9 kg.

Conclusions:

• Bioimpedance spectroscopy is a viable, low-cost tool for routine clinical assessment of peripheral muscle status in COPD patients.
• BIS measurements provide reliable estimations of quadriceps muscle thickness and isometric strength.
• This technology facilitates objective monitoring and evaluation of therapeutic strategies in COPD management.