Guidance
Rationale and impact
Diagnosis
Recommendations 1.3.4 and 1.3.5
Why the committee made the recommendations
Evidence showed that doppler ankle brachial pressure index below an agreed cut-off increased the probability of diagnosing peripheral arterial disease. However, people with diabetes and peripheral arterial disease may have a normal or raised index because of hardening of the arteries. The committee agreed that it was important to highlight this so that healthcare professionals do not exclude peripheral arterial disease in people with diabetes based on a normal or raised ankle brachial pressure index alone.
There was a lack of evidence on the use of pulse oximetry for diagnosing peripheral arterial disease in people with diabetes. The committee noted that a universal cut‑off point had not been established. This could lead to variation in the interpretation of results. It was also noted that pulse oximetry is rarely used in clinical practice for assessing peripheral arterial disease and there was general clinical agreement that it is not a useful test in this context. Therefore, the committee recommended against the use of pulse oximetry for this purpose.
There was not enough evidence on the use of other tests (doppler waveform analysis and toe brachial index) for diagnosing peripheral arterial disease in people with diabetes. However, the committee agreed it was not appropriate to make recommendations against the use of these tests, as there were good theoretical arguments as to why these tests might provide useful diagnostic value. The committee therefore agreed to make recommendations for research to inform future practice and any further update of this guidance.
Full details of the evidence and the committee's discussion are in evidence review A: determining the diagnosis and severity of peripheral arterial disease in people with diabetes.
Full details of the evidence and committee discussion for the original (2012) guideline are in the full guideline.
How the recommendations might affect practice
The new recommendations should improve the holistic assessment of peripheral arterial disease in people with diabetes. This is important because this group has a higher risk of cardiovascular events and foot problems such as diabetic neuropathy, foot ulcer and limb loss. The recommendation clarifies the use of ankle brachial pressure index and highlights the importance of interpreting pulse measurements in relation to clinical context, including symptoms.