Jelnes R
Department of Thoracic and Vascular Surgery T, Aalborg, Denmark.
Scand J Clin Lab Invest. 1990 Jun;50(4):351-61. doi: 10.3109/00365519009091591.
A method for continuous measurement of subcutaneous adipose tissue blood flow in the forefoot over 24 h (SBF) is described. The method is based on the radioisotope wash-out principle using 133-Xenon (133Xe). A portable semiconductor detector is placed just above a local depot of 37-74 kBq 133Xe in 0.1 ml isotonic saline, injected into the subcutaneous adipose tissue in the forefoot. The detector is connected to a memory unit allowing for storage of data. Because of the short distance, the recorded elimination rate constant must be corrected for combined convection and diffusion of the radioactive indicator. Characteristic 24-h blood flow patterns were unveiled in patients with normal peripheral circulation and in patients having ischaemic nocturnal rest pain. In normal subjects, SBF doubled from day to night. This is ascribed to the local veno-arteriolar sympathetic axon reflex, which induces vasoconstriction when the transmural pressure of the veins exceeds approximately 25 mmHg. In patients having ischaemic rest pains SBF was reduced by 37% on the average from day to night. This was caused by nocturnal hypotension, which is reflected proportionally in the foot. As the resistance vessels most probably are fully dilatated in feet with rest pain, the blood pressure drop during sleep causes the perfusion pressure and, therefore, blood flow to drop below a certain critical limit. There was a pronounced correlation between the reduction systemic mean arterial blood pressure and SBF. The patients complaining of intermittent claudication, but no rest pains, demonstrated a variety of changes in SBF compatible with the continuous spectrum of peripheral arteriosclerotic disease. The reduced blood flow during sleep in patients having ischaemic rest pains give rise to the concept of the development of gangrene during sleep.
本文描述了一种连续24小时测量前足皮下脂肪组织血流量（SBF）的方法。该方法基于使用133-氙（133Xe）的放射性同位素洗脱原理。将一个便携式半导体探测器放置在前足皮下脂肪组织中注入的0.1 ml等渗盐水中37-74 kBq 133Xe的局部储存库上方。探测器连接到一个允许存储数据的存储单元。由于距离较短，记录的消除速率常数必须针对放射性指示剂的对流和扩散进行校正。在正常外周循环患者和患有缺血性夜间静息痛的患者中揭示了特征性的24小时血流模式。在正常受试者中，SBF从白天到晚上增加了一倍。这归因于局部静脉-小动脉交感神经轴突反射，当静脉的跨壁压力超过约25 mmHg时，该反射会引起血管收缩。在患有缺血性静息痛的患者中，SBF从白天到晚上平均降低了37%。这是由夜间低血压引起的，足部会成比例地反映出来。由于患有静息痛的足部阻力血管很可能已完全扩张，睡眠期间的血压下降导致灌注压力下降，从而使血流量降至某个临界极限以下。全身平均动脉血压降低与SBF之间存在显著相关性。抱怨间歇性跛行但无静息痛的患者表现出与外周动脉硬化疾病连续谱相符的SBF多种变化。患有缺血性静息痛的患者睡眠期间血流量减少引发了睡眠期间坏疽发展的概念。
