Here is the procedure exactly as it appears on page 307 of
Portable RN: The All-in-One Nursing Reference, third edition, published by Lippincott Williams & Wilkins:
"More sensitive than palpation for determining pulse rate, the Doppler ultrasound blood flow detector is especially useful when a pulse is faint or weak. Unlike palpation, which detects expansion and retraction of the arterial walls, this instrument detects the motion of the red blood cells (RBCs).
- Apply a small amount of coupling or transmission gel (not water-soluble lubricant) to the ultrasound probe.
- Position the probe on the skin directly over the selected artery.
- When using a Doppler ultrasound blood flow detector model with a speaker, turn the instrument on. Moving counterclockwise, set the volume control to the lowest setting. If your model doesn't have a speaker, plug in the earphones and slowly raise the volume. The Doppler ultrasound stethoscope is basically a stethoscope fitted with an audio unit, a volume control, and a transducer, which amplifies the movement of RBCs.
- To obtain the best signals with either device, tilt the probe 45 degrees from the artery and apply gel between the skin and the probe. Slowly move the probe in a circular motion to locate the center of the artery and the Doppler signal--a hissing noise at the heartbeat [this is called the bruit].
- Avoid moving the probe rapidly because it distorts the signal.
- Count the signals for 60 seconds to determine the pulse rate.
- After you've measured the pulse rate, clean the probe with a soft cloth soaked in antiseptic solution or soapy water. Don't immerse the probe or bump it against a hard surface.
Documentation: Record the location and quality of the pulse, the pulse rate, and the time of the measurement."
FYI: We often marked patient's skin at the pulse point where you could hear the bruit with a clear "X" that could be seen by all.
Hope this is what you were looking for.