An evaluation of shunt flow by 133Xe clearance method and admittance plethysmography

The Xe-133-clearance method and the admittance plethysmography were simultaneously performed to measure the limb circulation in the normal subjects and in the diabetic patients. From the Xe-133-clearance curve, blood flow rates in the muscle (Fm) and in the skin (Fs) were separately measured. When the volume percent of the calf tissues was expressed as 70 % for the muscle and 10 % for the skin, the relationship between the total blood flow (Fy) measured by the admittance plethysmography and the nutrient flow (Fn) in the muscle and skin (Fn = 0.70 Fm + 0.1 Fs) was Fy = 1.22 Fn - 0.15 (ml/min/100 g tissue). The sum of the blood flow in the bone and the non-nutrient shunt flow was about 11 % of total blood flow in the calf. In the diabetic patients, the non-nutrient shunt flow increased associated with a reduction of the total flow in the calf. A combined study of the admittance plethysmography and the Xe-133-clearance method is useful to estimate the non-nutrient flow in the pathologic condition of lower extremities. (author)