
8
DIRECTIONS FOR USE
IndirectArterialBloodPressureMonitoringwiththeDopplerUnit
uClip the palmer aspect of the foot just proximal to the metacarpal pad. It is important to clip
the fur as short as possible. Rub a small amount of ultrasound gel on the skin in the midline
area where the palmer arterial arch is located. It can be palpated on large dogs and is actually
just slightly medial to the midline.
uPlace a large “dollop” of ultrasound gel on the non-numbered side of the Doppler ow probe.
Place the probe in the location of the artery described in above and tap it in place tightly.
(Turn on the Doppler unit with the ow probe plugged into the unit. The ow probe should not
be frequently disconnected from the unit as this loosens the connectors and wires in the unit).
uEnsure that the unit is charged. A swishing sound should be heard each time blood ows
through the artery. If blood ow is not heard, use the probe as a locator and move it slightly
until the swishing sound is heard and then re-tape in place.
uMake a loop in the cord of the ow probe. Tape the cord to the foot/metacarpal loop right
over the tape used to xate the ow probe to the skin initially.
uThe blood pressure cu is now in place. The cu’s width should approximate the width and
be up to two times that of the forearm (mid-radial region). It is applied so that the mid-section
on the rubber blade inside the cu is directly over the posterior medial aspect (where the
radial artery is located). This can be located by digitally occluding the area and hearing the
swishing sounds of the Doppler stop indicating the artery is at that location because its ow
is now temporarily blocked.
uWhen the cu is applied the INDEX line on the end of the cu should fall within the RANGE
on the cu, which is diagrammed on the inside. If outside this range, the reading will be either
falsely low (with cus too big for the size of the limb it is surrounding) or falsely high (with the
cu too small). An estimate can be arrived and that will indicate how far o, in percentage,
the cu reading will be, taken by observing the amount of length of the indexed area.
uA small amount of adhesive tape is added around the cu to prevent it from popping the
Velcro and showing a falsely high reading.
uThe cu is inated by squeezing the rubber bulb with the air outlet nozzle closed until the
manometer reading is 20-30mm Hg above when the swishing sound stopped. The air-outlet
nozzle is slowly opened and the cu is allowed to slowly deate. When the swishing sound is
rst heard again, this marks the ow of blood through the artery corresponding to SYSTOLIC
PRESSURE on the sphygmomanometer. The sound should be a shorter choppier sound than
was heard when the cu was not inated.
uThe cu deation is continued slowly as the characteristics of the swishing sound are
carefully monitored. A light “backward” sound or diastolic “swish” sound is again heard (or
as it is again sounded prior to any cu ination) corresponding to DIASTOLIC PRESSURE
when a very mild amount of “backow” in the artery occurs. The diastolic pressure is not
always evident.