Assessment of arterial disease using digital systolic pressure measurement.

Digital systolic pressure measurements were made on 140 big toes using a photoplethysmographic technique before and after extrinsic heating of the foot. Most patients with apparent, critically ischemic feet demonstrated vasomotor activity, suggesting that much of the microcirculation of the foot was in fact intact. Significantly, nine of 21 feet which would have fallen into a critically ischemic category were recategorized after heating into a less severe group. These data confirm the value of toe pressure measurements in the assessment of severe ischemia but show that adequate foot vasodilation is essential to allow accurate conclusions to be drawn and to allow meaningful interpretation of results.