We know there are some limitations with non invasive arterial testing. The big issue is its reliability with the diabetic population in terms of calcification of blood vessels. Oftentimes, we are told this is why one must perform toe indices as digital blood vessels are too small to get calcified.
I have documented in prior blogs that this is not always true and indeed one can have calcified digital vessels particularly in the diabetic patient.
another problem I seem to encounter with regularity is the patient with the so called "thunder thighs". This is the term of endearment for those thick thighs that could open a walnut if squeezed together.
I have found that these thighs often will produce a false negative waveform. Meaning the blood flow is usally better than what the actual test is showing. Why? improper fit of the cuff. The thunder thigh is shaped similiar to the inverted champagne bottle with the thicker proximal girth and a narrower distal girth. A blood pressure cuff is straight but circular when pplaced around a leg. Due to the uneven girth - the fit is not proper. The shape of the cuff needs to be different for these leg types. [Leg typing...lol]
Picture one all the way to the left shows a typical thunder thigh or inverted champagne shape. The first PVR waveform is from above the knee, the second waveform is below the knee or calf. The waveforms in a normal leg would show a decrease in amplitude from the above knee to the below knee not a reverse in amplitude.
One might say - maybe there is some form of blockage. Possibly, this is correct. Having seen a number of these patients who I in my earlier years sent off for a vascular consultation have a better understanding this is more likely an improper cuff fit. One can notice in the two pics on the end how the cuff on the distal portion of the above knee is looser fitting. Does anyone have any pearls to get a better reading on this leg type specific problem?
- Comments (0)