Patient Assessment

A patient with an arterial leg ulcer should be investigated following a full patient history. This will establish if the wound is an arterial ulcer caused by arterial insufficiency.

Some questions to ask:

• Has the patient experienced any pain?
• If the patient describes intermittent claudication, how far can they walk?
• If the patient says they have pain while resting, when did they first notice it and what measure do they take to relieve it?
• If the pain is in the foot, does getting up or hanging the foot over the edge of the bed help relieve pain?
• What position is most comfortable for the patient?

(Vuolo, 2009)

DIAGNOSIS

Specialist diagnostic tests are commonly used in the vascular laboratory to assess arterial flow to the extremities. Such examples include Duplex scanning and arteriography. The ABPI is usually used in the primary care setting to obtain an initial idea of arterial blood supply to the lower leg.

DUPLEX SCANNING

A duplex ultrasound scan will give further information – on arterial occlusion, stenosis, and areas of diffuse and continuous atheromatous disease (Grey et al., 2006). It is used to measure the blood flow in the arteries and veins of the legs and arms. A transducer probe with conducive gel is placed along different points of the vessel, and the data is viewed and recorded on an ultrasound monitor. Duplex scanning can accurately identify areas of thrombosis in blood vessels (Vuolo, 2009; British Heart Foundation, 2015).

ARTERIOGRAPHY

Is an invasive procedure and is performed by inserting a catheter into the arterial system. A contrast medium is injected, and an X-ray is taken as the medium is injected. The resulting image shows the lumen of the artery and any defect present. The defect can also be corrected during this procedure (Vuolo, 2009; British Heart Foundation, 2015).

ABPI

The ankle brachial pressure index is helpful in identifying peripheral arterial disease in the absence of non-compressible vessels resulting from vessel calcification (for example, diabetes) or tissue oedema (Grey et al., 2006).

As discussed earlier, ABPI can be used in the community setting to provide an initial diagnosis of arterial insufficiency. The technique is the same as that described for venous ulceration.

When interpreting ABPI in a person with arterial/PAD/IC disease, a ratio of:

• Less than <0.5 arterial rest pain and/or ulceration could suggest severe peripheral arterial disease or critical limb ischaemia (CLI). If CLI is present, an urgent referral to vascular services is required – patient should be seen within 2-14 days. If there is concern regarding acute limb ischaemia, an urgent (within 4 hours) consultation with GP (or other qualified specialist), to ascertain a hospital admission. If there is a sudden deterioration of patient or limb, arrange urgent discussion with GP (or other qualified specialist), for pain relief and optimisation of perfusion. Consider referral to vascular services.
• Between 0.5 and 0.8 suggests the presence of arterial disease or mixed arterial/venous disease. Compression should generally be avoided. However, reduced compression can be used under specialist advice and with strict supervision. Refer the person for specialist vascular assessment.

(Wounds UK, 2019)

Care must be taken in interpreting ABPI results in people with these conditions, as they may be misleadingly high.

For ABPI interpretations 0.8 and above, please refer to the following sections: Patient Assessment - Interpretation of ABPI and Relationship Between Venous Ulceration and Compression.

Compression therapy should be used with caution in people with diabetes, who may have unreliable ABPIs due to arterial calcification as well as an underlying sensory neuropathy. Refer to a specialist vascular service as further assessments may be required. (NICE, 2015, 2019; Wounds UK, 2019)