Parks 915-BL, Operating & Service Manual

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13
915-BL Dual Frequency Doppler
Diagnostic Procedures
Preoperative and Postoperative Blood Pressure (BP) Measurements
The Doppler is used to monitor blood pressures before and after lower extremity vascular surgery.
Measure and record 1. systolic pressure at both ankles immediately prior to surgery.
When the 2. blood fl ow is restored in the treated leg, measure both blood pressures again.
The pressure of the treated ▪ leg should be higher than that of the non-treated leg.
Reactive hyperemia following surgery may result in equal or lower pressure of the affected leg on ▪
rare occasions, but the leg will be warm to the touch.
Blood pressure measurements provide an objective evaluation of the surgery. Some surgeons ▪
use the pencil probe (or optional microtip probe) directly on the artery (with sterile jelly for
coupling) just distal to the repair. Critical evaluation of the
fl ow sound detects problems which can
be corrected during surgery.
Follow up after surgery by measuring pressures and obtaining 3. ankle/brachial indices.
Upper Extremity Arterial Evaluation
The optional fl at probe can be used to make repeated systolic pressure measurements in the radial artery.
Positioning the Flat Probe
1. Position the fl at probe over the radial artery with the cord lying across the hand; this will orient the
crystals to point cephalad (antegrade).
Use a Velcro strap or tape to hold the probe in place, and anchor the cord at least one place distal
2.
to the probe.
Upper Extremity Segmental Systolic Pressures
Doppler segmental pressures are taken with an appropriately-sized cuff aligned so the bladder is directly
over the artery being measured. Bilateral systolic pressures are obtained at these sites:
Upper arm, using the 1. brachial artery.
Forearm, using the radial or 2. ulnar arteries.
The differences in pressure readings between extremities and between the sites on each arm can be
diagnostic for a stenosis or an occlusion.
Venous Evaluation
Venous Doppler testing is the most subjective test done in the vascular laboratory. To provide consistent,
reproducible results, the technologist must be thoroughly familiar with venous anatomy (including
deviations from normal) and the subtleties of venous Doppler signals.
Veins are located by fi rst fi nding the artery, and then moving the probe slightly to either side of the arterial
signal until the characteristic windstorm-like sound of venous fl ow is heard.
Doppler studies can be used to assess patients for the presence of occlusions, deep vein thrombosis
(DVT), and valvular incompetence associated with varicose veins. Doppler studies can detect
spontaneous venous
fl ow, which is phasic with respiration, and augmentation with distal compression.
See standard textbooks for more information.