Does the measurement of digital arterial pressure using the Doppler ultrasonic technique without testing for vasospasm to detect digital arterial occlusions make good sense?

Abstract

Background: An attempt was made to determine whether measurement of the systolic pressure with the Doppler ultrasonic technique can be used to detect occlusions of the digital arteries.

Patients and methods: A total of 92 patients (44 women, 48 men) with an average age of 47.5 years (range: 19-82 years) were investigated. Of these, 17 were diagnosed with a primary Raynaud's syndrome, 45 with a secondary, and 5 patients with a suspected secondary Raynaud's syndrome; 25 patients had digital occlusions of varying genesis. In all patients, the Doppler ultrasonic technique was applied to measure the systolic pressure of the digital arteries of both hands at a room temperature of 21-24 degrees Celsius without any additional thermal (warm or cold) provocation or use of vasodilatory agents; the results obtained were compared with arteriographs of the hands.

Results: While the sensitivity of the Doppler ultrasonic technique was a very low 55%, the specificity was a very high 95%. With a prevalence of 68%, the positive predictive value was 96%, the negative predictive value 50%. In the case of angiographically patent digital arteries with no spastic narrowing, the Doppler ultrasonic-measured systolic pressure was up to 30 mmHg above, and up to 25 mmHg below, the systolic pressure measured in the ipsilateral brachial artery. A pressure gradient between upper arm and digital arteries of this order of magnitude therefore does not exclude pathological changes. Only angiography was able reliably to detect vascular stenoses and occlusions.

Conclusion: Reliable exclusion of digital arterial occlusions using the Doppler ultrasonic technique without testing for vasospasm is not possible. Only occlusions of digital arteries together with simultaneous occlusions of hand arteries can be reliably detected. Owing to the considerable scatter of the systolic blood pressure gradient between brachial and digital arteries, the Doppler ultrasonic technique cannot be used to distinguish between patent and occluded digital arteries without the use of additional vasodilation.