Bergersen Tone Kristin, Walløe Lars
Department of Dermatology, Oslo University Hospital and Institute of Clinical Medicine, University of Oslo, Oslo, Norway.
Department of Physiology, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
Handb Clin Neurol. 2018;157:677-685. doi: 10.1016/B978-0-444-64074-1.00040-9.
The term acral coldness is used to describe physiologic or pathologic situations in humans where the fingers and toes are exceptionally cold in spite of normal central body temperature. In the thermoneutral zone, the blood flow to acral skin normally shows large fluctuations between high and low values, with a frequency of about 3 cycles per minute. At an acral skin temperature of about 21°C, finger blood flow is constantly low. At lower temperatures the fingers and toes become painful. This is a normal physiologic reaction, probably because of ischemia. The characteristics of the most frequent acral vascular syndromes, Raynaud phenomenon, acrocyanosis, and chilblains, are discussed. Common to all three is pathologically low blood flow and disappearance of physiologic fluctuations even in the thermoneutral zone. Ischemic vascular diseases in acral skin are usually diagnosed from clinical observations. Measurements of fluctuating blood flow by laser or ultrasound Doppler could be useful, but should be carried out at a room temperature of 24-25°C.
“肢端寒冷”一词用于描述人类的生理或病理状况，即尽管身体核心温度正常，但手指和脚趾却异常寒冷。在热中性区，流向肢端皮肤的血流量通常在高值和低值之间有较大波动，频率约为每分钟3个周期。在肢端皮肤温度约为21°C时，手指血流量持续较低。在更低温度下，手指和脚趾会疼痛。这是一种正常的生理反应，可能是由于缺血所致。文中讨论了最常见的肢端血管综合征——雷诺现象、手足发绀症和冻疮的特征。这三种病症的共同之处在于病理性的低血流量以及即使在热中性区生理波动也消失。肢端皮肤的缺血性血管疾病通常通过临床观察来诊断。用激光或超声多普勒测量波动血流量可能会有帮助，但应在室温24 - 25°C下进行。
