Radial Brachial Index is probably the right one (though not what's used, to my knowledge), or Arterial Pressure Index when using the Doppler. But I don't take responsibility for the
naming convention.
Taken from a 2017 BMJ article by Feliciano:
“Patients presenting with ‘soft’ signs of an arterial injury—history of bleeding at the scene or during transport, proximity of a penetrating wound or contusion/hematoma/fracture, a non-pulsatile hematoma or a neurologic deficit—underwent diagnostic imaging in the past. The historic yield on either emergency center arteriography performed by surgeons or formal arteriography performed in an interventional radiology suite for a ‘soft’ sign was under 4% to 5%.
11 Various combinations of soft signs occasionally led to positive arteriograms in up to 13% to25% of patients, but the lesions diagnosed were non-occlusive, as expected, and were managed non-operatively over time as previously noted.
2–4 12 13
The pitfall of overusing traditional imaging to rule out non-operative arterial injuries has been minimized in the past 25 years. This has been accomplished by the measurement of the ABI or BBI or arterial pressure index (API) in injured extremities for the past 25 years.
14–16 Using the original cut-off of ≥0.9 as described by Johansen and Lynch, a patient with an ABI or API at this level is presumed to have a normal artery or one with a small non-occlusive lesion (intimal injury/intramural hematoma/small traumatic false aneurysm).
14 Any lesion such as this is managed with observation and/or repeat imaging but not an operation.”
So, in essence, with brachial brachial index we rule out immediately operable lesions, but not intimal injury.
I would obs someone with intimal injury vs send someone without it home. So doing the extra imaging does have value to me.
I would rather completely see what is going on than have a patient go home with an intimal injury and later thrombose the artery and lose a limb, especially in the case of a young healthy person.
As a trauma surgeon who is a taking care of a multi system trauma patient who is likely going to be in house anyways, I think a non invasive index is a great way to triage your care.
As a vascular surgeon, I want to know about the intimal injury and ensure obs and close follow up if the mechanism is worrisome.