Cold-Induced Skin Perfusion Adaptive Responses: Comparing ICE and PORH Mechanisms In Vivo

Ice cooling exposure (ICE) is an interesting, but little explored, technique used to examine human peripheral microcirculatory adaptive mechanisms. In this study, we compare in vivo perfusion changes assessed by laser Doppler flowmetry (LDF) during post-occlusive reactive hyperemia (POHR) and ICE procedures. Eleven healthy women, 29.3±7.3 years old, were selected and sequentially submitted to PORH and ICE procedures in one randomly selected upper limb. Blood perfusion and skin temperature were continuously measured in both hands during baseline (phase I) challenge (phase II) and recovery (phase III). Procedures respected all clinical research principles and were previously submitted to the institutional ethics committee. PORH and ICE evoked significant decreases in skin perfusion in phase II followed by reperfusion in the intervention limb, although with different velocities. Similar significant responses were obtained in the contralateral limbs. Correlation among variables could not be found, except between LDF and temperature signals across phases. Results suggest that ICE is better tolerated than POHR when used with the same objective. More studies are needed to confirm if reflexes elicited by these approaches are equivalent and equally suitable for application in vascular medicine.