Wearable Neuromuscular Electrical Stimulation on Quadriceps Muscle Can Increase Venous Flow

• Published in: Annals of biomedical engineering Vol. 51; no. 12; pp. 2873 - 2882
• Main Authors: Flodin, Johanna, Wallenius, Philip, Guo, Li, Persson, Nils-Krister, Ackermann, Paul
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01.12.2023; Springer Nature B.V
• Subjects: Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biomedical Engineering and Bioengineering; Biomedicine; Biophysics; Blood flow; Classical Mechanics; Deep vein thrombosis; Discomfort; Doppler effect; Electrical stimulation therapy; Electrical stimuli; Muscle contraction; Muscle stimulation; Muscular function; Neuromuscular electrical stimulation; Original Article; Parameters; Peak venous velocity; Quadriceps muscle; Risk reduction; Skeletal muscles; Smart textiles; Stimulation; Textile electrodes; Thromboembolism; Thromboprophylaxis; Venous thromboembolism; Smart textiles; Peak venous velocity; Skeletal muscles; Muscle stimulation; Deep vein thrombosis; Thromboprophylaxis; Electrical stimulation therapy; Venous thromboembolism; Textile electrodes
• ISSN: 0090-6964; 1573-9686; 1573-9686
• DOI: 10.1007/s10439-023-03349-0

Neuromuscular electrical stimulation (NMES) of the quadriceps (Q) may increase venous blood flow to reduce the risk of venous thromboembolism. This study assessed whether Q-NMES pants could increase peak venous velocity (PVV) in the femoral vein using Doppler ultrasound and minimize discomfort. On 15 healthy subjects, Q-NMES using textile electrodes integrated in pants was applied with increasing intensity (mA) until the first visible muscle contraction [measurement level (ML)-I] and with an additional increase of six NMES levels (ML II). Discomfort using a numeric rating scale (NRS, 0–10) and PVV were used to assess different NMES parameters: frequency (1, 36, 66 Hz), ramp-up/-down time (RUD) (0, 1 s), plateau time (1.5, 4, and 6 s), and on:off duty cycle (1:1, 1:2, 1:3, 1:4). Q-NMES pants significantly increased PVV from baseline with 93% at ML I and 173% at ML II. Frequencies 36 Hz and 66 Hz and no RUD resulted in significantly higher PVV at both MLs compared to 1 Hz and 1 s RUD, respectively. Plateau time, and duty cycle did not significantly change PVV. Discomfort was only significantly higher with increasing intensity and frequency. Q-NMES pants produces intensity-dependent 2−3-fold increases of venous blood flow with minimal discomfort. The superior NMES parameters were a frequency of 36 Hz, 0 s RUD, and intensity at ML II. Textile-based NMES wearables are promising for non-episodic venous thromboembolism prevention.