Cryotherapy-Induced Persistent Vasoconstriction After Cutaneous Cooling: Hysteresis Between Skin Temperature and Blood Perfusion

Abstract

The goal of this study was to investigate the persistence of cold-induced vasoconstriction following cessation of active skin-surface cooling. This study demonstrates a hysteresis effect that develops between skin temperature and blood perfusion during the cooling and subsequent rewarming period. An Arctic Ice cryotherapy unit (CTU) was applied to the knee region of six healthy subjects for 60 min of active cooling followed by 120 min of passive rewarming. Multiple laser Doppler flowmetry perfusion probes were used to measure skin blood flow (expressed as cutaneous vascular conductance (CVC)). Skin surface cooling produced a significant reduction in CVC (P < 0.001) that persisted throughout the duration of the rewarming period. In addition, there was a hysteresis effect between CVC and skin temperature during the cooling and subsequent rewarming cycle (P < 0.01). Mixed model regression (MMR) showed a significant difference in the slopes of the CVC-skin temperature curves during cooling and rewarming (P < 0.001). Piecewise regression was used to investigate the temperature thresholds for acceleration of CVC during the cooling and rewarming periods. The two thresholds were shown to be significantly different (P = 0.003). The results show that localized cooling causes significant vasoconstriction that continues beyond the active cooling period despite skin temperatures returning toward baseline values. The significant and persistent reduction in skin perfusion may contribute to nonfreezing cold injury (NFCI) associated with cryotherapy.

Heat Transfer in Health and Healing1

“…It occurs for both slow and rapid cooling and warming, i.e., across many time scales [77]. The growing body of scientific and clinical data indicate that the relationship between temperature and local blood perfusion plays an important role in determining the outcome of cryotherapy procedures.…”

“…Given the direct dependence of the efficacy of thermal therapy on the modulation of local blood flow, we have conducted extensive human trials to quantify the domains of coupling and uncoupling of perfusion to temperature [75][76][77]. A wide range of CTUs have been tested with thermocouples and laser Doppler blood flow probes placed on the skin surface under the ice water perfusion bladder and at other control locations.…”

Quantitative Evaluation of the Thermal Heterogeneity on the Surface of Cryotherapy Cooling Pads

“…It is recognized that a key action of cryotherapy is to reduce the rate of blood flow to the target tissue as the temperature is lowered. The sensitivity of the physiological response to an applied cooling temperature as portrayed in terms of modulation in skin blood perfusion has been measured in experiments parallel to those described in this paper and is reported in other publications [25][26][27]. The coupling between an applied therapeutic temperature and the changes produced in skin blood flow is a key component dictating the efficacy of cryotherapy regimens.…”

An On-Site Thermoelectric Cooling Device for Cryotherapy and Control of Skin Blood Flow

“…Thus, the occurrence here is anticipated. The interdependence of temperature and perfusion during a cooling and heating cycle will result in a hysteresis effect when these properties are plotted together [28].…”