The toe pole test for evaluation of arterial insufficiency in diabetic patients

Abstract

Objectives: to evaluate if the pole test at the toe level can be used for assessment of arterial insufficiency in diabetic patients.

Methods: twenty-five legs in 23 diabetic patients suffering from leg ischaemia were examined prospectively. A laser Doppler probe was attached to the pulp of the first toe to monitor perfusion continuously before and after occluding the arterial inflow with a cuff and during elevation of the leg until perfusion disappeared (the pole test). At ankle level the examinations were made similarly but with an ankle cuff and a hand-held Doppler.

Results: in the 44% (11/25) of the legs where it was possible to compare cuff blood pressure at ankle level with the pole test, the cuff measurements were significantly higher (p <0.01). In 13 of the remaining 14, maximal elevation did not result in disappearance of the Doppler signal. At toe level where 76% (19/25) of the legs could be compared, there was no significant difference between the two methods.

Conclusion: the pole test can be used at the toe level to evaluate arterial insufficiency in diabetes. When used in the toe, the pole test can assess pressures below 55-70 mmHg, while only pressures below 45 mmHg can be determined at the ankle level. Falsely elevated blood pressure in diabetics is probably of less importance in digital arteries than in ankle arteries, which makes cuff pressure at toe level a more acceptable approximation.