Abstract
The intra-arterial blood pressure was measured in the brachial and posterior tibial arteries in 13 normal subjects and compared with the blood pressure measured indirectly using the strain-gauge technique and 12 × 26 cm occluding cuffs on the arm and ankle. On the arm, the average intra-arterial blood pressure was 128/71 mm Hg, the auscultatory blood pressure 123/77 mm Hg, while the average systolic blood pressure measured by strain-gauge technique was 118 mm Hg. At the ankle, the intra-arterial blood pressure was 154/72 mm Hg, and the average strain-gauge blood pressure 142 mm Hg, thus demonstrating that systolic blood pressure is about 25 mm Hg higher in the posterior tibial arteries than in the brachial artery. Indirect measurements of the systolic blood pressure was about 10 mm Hg lower than the corresponding intra-arterial values for both the arm and the ankle.