Moisture-Responsive Thermal Conductivity Properties of Hydrofiber Versus Polyurethane Foam: Implications for Pressure Injury Prevention

Abstract

Effective thermal management at the skin-dressing interface is essential in pressure injury prevention by means of prophylactic dressings. This study quantified the thermal conductivity of AQUACEL Hydrofiber Technology (AHT, hydrofiber) and polyurethane foam dressing materials under normothermic (32 degrees C) and febrile (40 degrees C) conditions across increasing moisture levels. Using a validated custom heat-flow meter system, dry hydrofiber exhibited significantly greater thermal conductivity than the polyurethane foam (0.43 +/- 0.01 vs. 0.20 +/- 0.01 W/m K at 32 degrees C; p < 0.001). Upon hydration at 32 degrees C, thermal conductivity values increased nonlinearly for both materials but to a much greater extent for the hydrofiber. At 15% moisture, the hydrofiber reached 4.73 +/- 0.12 W/m K compared to the polyurethane foam at 1.03 +/- 0.02 W/m K. At 40 degrees C, hydrofiber achieved 3.39 +/- 0.19 W/m K with only 10% moisture, indicating a temperature-responsive biphasic transformation. Overall, hydrofiber demonstrated a fivefold greater thermal conductivity response to moisture than the polyurethane foam. These findings highlight critical, material-dependent differences in heat dissipation under clinically relevant conditions. The superior moisture-responsive thermal conductivity of hydrofiber highlights its potential to improve heat dissipation at the skin-dressing interface under clinically relevant conditions and thereby mitigate local heat accumulation, contributing to skin protection. Thermal conductivity and thermal adaptability studies should be integrated into dressing efficacy research and be used for selection criteria for pressure injury prevention programs alongside mechanical and absorptive performance.