Extreme Environments Laboratory, Department of Sport and Exercise Science, University of Portsmouth, Portsmouth PO1 2ER, UK.
Eur J Appl Physiol. 2013 Sep;113(9):2411-7. doi: 10.1007/s00421-013-2678-8. Epub 2013 Jun 13.
The presumption in a cold sensitivity test (CST) used for cold injuries is that the skin temperature (T sk) observed reflects the return of blood flow to the extremity following a local cold challenge. We questioned this assumption.
Six non-cold injured participants undertook two CSTs in 30 °C air. The control (CON) CST involved 12 min gentle exercise prior to immersing the foot into 15 °C water for 2 min followed by 15 min of spontaneous rewarming. The occlusion (OCC) CST was the same except that blood flow to the foot was occluded during the rewarming period. These results were compared to CSTs from six individuals with non-freezing cold injury and moderate-severe cold sensitivity (CS) and a non-perfused human digit model (NPDM).
Before immersion, great toe skin blood flow (SkBF) was similar in CON and OCC conditions [255 (107) laser Doppler units (LDU)] and was higher than CS [59 (52) LDU]. During rewarming, SkBF in CON returned to 104 % of the pre-immersion value and was higher than both OCC and CS. Great toe T sk before immersion was lower in CS [28.5 (2.1) °C] compared to CON [34.7 (0.4) °C], OCC [34.6 (0.9) °C] and NPDM [35.0 (0.4) °C]. During rewarming skin/surface temperature in OCC, CS and NPDM were similar and all lower than CON.
SkBF does contribute to the skin rewarming profile during a CST as a faster rate of rewarming was observed in CON compared to either OCC or NPDM. The lower T sk in CS may be due to a reduced basal SkBF.
用于冷伤的冷敏测试（CST）中的一个假定是，观察到的皮肤温度（T sk）反映了局部冷刺激后血流返回肢体。我们对这一假设提出质疑。
6 名非冷伤参与者在 30°C 的空气中进行了 2 次 CST。对照（CON）CST 包括在将脚浸入 15°C 的水中 2 分钟之前进行 12 分钟温和运动，然后进行 15 分钟自发复温。闭塞（OCC）CST 相同，只是在复温期间阻断脚部血流。将这些结果与 6 名非冻结性冷伤和中度至重度冷敏（CS）个体以及非灌注人数字模型（NPDM）的 CST 进行比较。
在浸入之前，CON 和 OCC 条件下的大脚趾皮肤血流（SkBF）相似[255（107）激光多普勒单位（LDU）]，高于 CS [59（52）LDU]。在复温过程中，CON 中的 SkBF 恢复到浸入前值的 104%，高于 OCC 和 CS。在浸入之前，CS [28.5（2.1）°C] 的大脚趾 T sk 低于 CON [34.7（0.4）°C]、OCC [34.6（0.9）°C] 和 NPDM [35.0（0.4）°C]。在复温过程中，OCC、CS 和 NPDM 的皮肤/表面温度相似，均低于 CON。
SkBF 在 CST 期间确实有助于皮肤复温，因为与 OCC 或 NPDM 相比，CON 观察到更快的复温速率。CS 中较低的 T sk 可能是由于基础 SkBF 降低所致。
