Evaluation of an automated ankle- brachial pressure index calculator in a nurse-led leg ulcer clinic

Holistic assessment of leg ulceration is vital prior to the implementation of effective, person-centred treatment pathways and should include the following: past medical and social history, physical examination, structured wound assessment, pain assessment, mobility assessment, clinical investigations and assessment of arterial blood flow (Moffatt, 2008). The Management of Chronic Venous Leg Ulcers guideline (Scottish Intercollegiate Guidelines Network [SIGN], 2010) recommends carrying out an ankle-brachial pressure index (ABPI) using a Doppler ultrasound and blood pressure (BP) sphygmomanometer to determine the presence of arterial disease prior to implementing compression therapy; however, as with any diagnostic procedure, results should be interpreted within the context of additional holistic factors and should not be viewed in isolation. Additionally, clinicians should be aware that there is currently no diagnostic test for venous disease available in the community setting and that ABPI only confirms the presence or absence of peripheral arterial disease (PAD), therefore, assessing patients’ suitability for compression therapy (Vowden and Vowden, 2001). Doppler assessment comprises two important diagnostic components: determination of ABPI and interpretation of audible waveforms (Ruff, 2003). ABPI provides a ratio of arterial blood flow in the brachial arteries compared to those in the foot, and is therefore a useful diagnostic indicator in determining how perfused a limb is. The type of the waveform can also provide important information about the quality of arterial circulation. For example, a person may have a normal ABPI (which ranges from 0.8 to 1.3 in some areas of the The Dopplex Ability® is a new automated ankle-brachial pressure index (ABPI) calculator, the increased use of which the authors are witnessing in clinical practice. Proposed benefits over the traditional hand-held Doppler machine and manual blood pressure (BP) sphygmomanometer include: ease of use, reduced procedure time and reduced time lying flat for patient, which may lead to more cost-effective treatment outcomes. Since it is routine practice in a number of clinical areas for two members of staff to carry out the holistic leg ulcer assessment process, an additional benefit may be the ability of a single member of staff with minimum training to use the Dopplex Ability. An evaluation of the Dopplex Ability was carried out at a busy nurse-led community leg ulcer clinic over a period of 3 months. A total of 22 patients who attended the clinic for Doppler assessment consented to participate. Participants underwent ABPI calculation using both the Dopplex Ability and the hand-held Doppler. Overall 56% of readings were marginally higher with the Dopplex Ability than with the hand-held Doppler; 9% of readings were lower and 34% were equal. ABPI readings from the Dopplex Ability equipment were on average 0.067 higher than corresponding readings taken from hand-held equipment; this difference was statistically significant (p=0.014). Differences between methods were greater in patients who had readings taken by the Dopplex Ability first than in patients who had hand-held readings taken first. The majority of patients found the Dopplex Ability to be tolerable and staff found it easy to use. The Dopplex Ability was found to be a useful adjuvant to the hand-held Doppler.