Can BlueDop be used as an alternative for diagnosing peripheral arterial disease? A prospective comparison of traditional ABPI and TBPI with BlueDop

Abstract

Objectives

Ankle and toe brachial pressure index are recommended globally as first line non-invasive screening tests for peripheral arterial disease. However, they can be inaccurate and have limited utility in patients with incompressible arteries, lower limb wounds and/or lack of digits. This study aims to evaluate BlueDop, a novel device that purports to assess peripheral perfusion without the need for a lower limb tourniquet or patients lying flat.

Methods

Patients attending vascular and podiatry clinic at Aneurin Bevan University Health Board were recruited between May 2022 and May 2023. A BlueDop reading was recorded in addition to ankle and/or toe brachial pressure index. Satisfaction and preference of each method was recorded using an electronic proforma.

Results

176 patients were included. BlueDop ABPI was shown to be moderately correlated with cuff-ABPI (r_s = 0.42, p = .001) and weakly correlated with TBPI (r_s = 0.22, p = .04). BlueDop had moderate accuracy in diagnosing PAD (C statistic = 0.653) and was more accurate in diagnosing severe PAD (C statistic = 0.706). Diagnostic accuracy appeared to be improved when PAD was defined according to cuff-ABPI only. Patients were more satisfied with BlueDop (mean satisfaction score (MSS) = 4.33) compared to cuff-ABPI (MSS = 2.89, mean difference = 0.544, p < .001) and TBPI (MSS = 3.82, mean difference = 0.579, p < .001) while operator satisfaction was equal.

Conclusions

There is moderate correlation between BlueDop and cuff-ABPI. Patients prefer BlueDop to cuff-ABPI or TBPI. BlueDop appears to be an acceptable method of non-invasive assessment of PAD, although users must appreciate there is a discrepancy between it and cuff-ABPI/TBPI.