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How do we assess for arterial disease in the lower limb?

  1. Is the leg white and hairless?
  2. Is the limb and foot cold
  3. Are the toes blue or dark red?
  4. Are there any black spots over the toes (or foot)
  5. Use an oximeter (Fig 1) to test the oxygen levels in the micro circulation. You can expect the levels to be between 94% and 98%. Less than 90% means the microcirculation is not functioning well (report to the GP). The oximeter can only be used if the toes are small enough and nails not too thick (can be purchased online for £29)
Figure 1. Oximeter

6. Pinch the great toe nail (Fig 2). It should be white when you release the pressure and flush pink fairly quickly. This is known as the capillary nail refill test. The speed of that reflush will tell if the microcirculation is not good. It should take 3 seconds to reflush to normal. Longer demonstrates poor delivery of blood to the tissues. Longer than 7 seconds should be reported to the GP for vascular consideration.

Figure 2. Pinch the toe nail

7. Does the client walk? If yes, do they develop pain when walking that eases at rest? This is an indication of intermittent claudication. Report to the GP.

8. Use a Hand Held Doppler (Figs 3 and 4) to listen to the sounds in the foot. These sounds should be 3 beats for a healthy artery. This demonstrates good arterial sounds. 2 beats are reasonably normal. One beat that sounds like a dog barking with a long drawn out WOOF, WOOF! This demonstrates that the macro circulation (large vessels inside the calf) is diseased with atherosclerosis. The GP must be informed and a request for an Ankle Brachial Pressure Index to be carried out by a Tissue Viability Nurse if at all possible. This could be an emergency. Act quickly. Heel ulcers are a huge threat in this case.

The Doppler required for this test is a simple one as it is not a full Ankle Brachial Pressure Index that is required. A simple Vascular Doppler can be obtained from sites, such as Ebay, for £32. This should be a small, pointed probe – not a flat foetal probe although the Doppler will have ‘Pocket Fetal Doppler’ on the front – this can be ignored. It is the probe that is important. All nursing homes should own one and everyone taught how to listen for the sounds. It does not inform of the level of arterial disease but allows the nurse to understand the need for vascular referral and for protection of the heels and toes.

The positions for the Doppler to pick up the sounds are shown in Figure 3 and 4. The Doppler is placed at a 90 degree angle until the sound is picked up and then is placed at 45 degree angle facing the heart so that the blood advances toward the probe.

The above tests are simple and will not give a diagnosis but it will provide enough evidence for an alert to be sent to the GP. The GP may consider referring the client to a Vascular Consultant for further investigations. Any reversal of this problem will greatly reduce the risk of pressure ulcers on the heel and reduce the risk of peripheral arterial disease problems at a later date.

Figure 3. The Doppler Probe requires gel in order to make contact. There are 3 places to pick up the sounds. Most commonly used is the dorsalis pedis – demonstrated in the picture.
Figure 4. One of the easiest places to pick up the sound is at 3 O’clock on the inner aspect of the ankle. However, everyone is different.

For more help or information on the prevention and treatment of pressure ulcers ask OSKA. To view the range of OSKA pressure relieving equipment click here.