Segmental blood pressure of the leg and its clinical use

Systolic blood pressure at various levels of the leg was measured in 80 normal subjects by photoelectric plethysmography with a blood pressure cuff. Due to the higher pressure value at the thigh, calf, ankle, and foot and lower pressure value at the toe, the pressure gradient between each proximal site and the toe was significantly higher in the older (50-82) than in the younger age group (17-49). Therefore, normal values were determined separately in these two groups. In 64 limbs of 42 patients with arterial occlusive disease, a comparison between segmental blood pressure and arteriographic findings was made. Segmental blood pressure may be a rough indicator of the severity of arterial occlusion present and may refrect the status of the major conduits of the leg. An abnormal ankle-toe pressure gradient was found in only 52 per cent of limbs, although all 64 limbs had undergone an occlusive process distal to the ankle. In limbs with significantly low ankle blood pressure due to proximal lesions, less frequency and severity of an abnormal ankle-toe pressure gradient were seen than in limbs with normal ankle blood pressure. When pressure gradients between two different levels are used in clinical work, the blood pressure at the more proximal level should be always considered.