Computational investigation of intermittent pneumatic compression operating parameters and tissue mechanics in lower-limb venous hemodynamics.

Intermittent pneumatic compression (IPC) is widely used for the prevention and management of chronic venous insufficiency (CVI); however, the relationships among IPC operating conditions, tissue mechanics, and venous hemodynamics remain incompletely understood. This study develops a multi-fidelity fluid-structure interaction (FSI) framework to investigate the effects of IPC parameters and lower-limb tissue properties on venous flow, pressure, and wall shear stress (WSS). The framework couples one-dimensional deformable blood flow with three-dimensional tissue mechanics and a lumped-parameter upstream venous network, enabling computationally efficient, mechanistically grounded simulations. Parametric analyses were performed using both an idealized cylindrical geometry and a subject-specific model reconstructed from medical imaging. Chamber number, compression hold time, peak compression pressure, and tissue properties derived from body fat statistics were systematically varied. Results show that peak compression pressure and hold duration are the primary determinants of venous hemodynamic modulation. Higher pressure increased lumen narrowing and flow pulsatility, while longer hold times promoted distal blood accumulation and elevated peak flow and pressure. In contrast, chamber number had a minor effect under uniform actuation. More compliant tissues exhibited stronger deformation and hemodynamic responses. IPC also consistently increased WSS due to combined flow augmentation and lumen reduction. Ultrasound measurements further demonstrated IPC-induced increases in femoral venous velocity and cross-sectional area, supporting the model predictions. Overall, this study provides quantitative, mechanics-based insight into IPC-induced venous transport and supports the optimization of patient-specific compression strategies.