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extremity.

Auscultation

Systemic blood pressure and the presence of bruits (whooshing sound

indicative of turbulent blood flow from obstructions) are assessed

through auscultation.' Bruits are typically assessed by physicians and

nurses (see Chapter 1 for further details on blood pressure measurement).

Vascular Tests

Various tests that can be performed clinically to evaluate vascular flow

and integrity are described in Table 6-4. These tests can be performed

easily at the patient's bedside without the use of diagnostic equipment.

Diagnostic Studies

Noninvasive Laboratory SlIIdies

Various noninvasive procedures can examine vascular now. The

phrases lower-extremity noninvasive studies and carotid noninvasive

studies are general descriptions that are inclusive of the noninvasive

tests described in Table 6-5.

Invasive Vascular Studies

The most common invasive vascular study is arteriography, typically

referred to as contrasr angiography. This study provides anatOmic and

diagnostic information about the arterial system by injecting radiopaque dye into the femoral, lumbar, brachial, or axillary arteries, followed by radiographic viewing. An angiogram is a picture produced by angiography. Angiography is generally performed before or during

therapeutic interventions, such as percutaneous angioplasry, thrombolytic therapy, or surgical bypass grafting.

Postangiogram care includes the followingS:

•

Bed rest for 4-8 hours.

•

Pressure dressings to the injection site with assessment for

hematoma formation.

•

Intravenous nuid administration to help with dye excretion.

Blood urea nitrogen (BUN) and creatinine are monitored to ensure

proper renal function (refer to Chapter 9 for more information on

BUN and creatinine).

Table 6-4. Vascular Tests

Test

Indication

Description

Normal Results and Values

Capillary refill

To assess vacular

Nail beds of fingers or toes are

Blanching should resolve (capillary refill)

time

perfusion and

squeezed until blanching (whitenin less than 3 sees.

indirectly assess

ing) occurs, and then they are

cardiac ourpO[

released.

Elevation pallor

To assess anerial

A limb is elevated 30-40 degrees, and

Grading of palloro

perfusion

color changes are observed over 60

o = no pallor in 60 sees

sees.

1 = pallor in 60 sees

A gray or pale (pallor) discoloration

2 = pallor in 30-60 sees

will result from arterial insuffi3 = pallor in less than 30 sees

ciency or occlusion.

4 = pallor with limb flat (not elevated or

dependent)

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Trendelenburg's

To determine if

A tourniquet is applied

<;:

ro the

Greater saphenous veins are involved if

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test

superficial or deep

involved lower extremity, which is

the varicosities fill slowly with the

�

""

veins are involved

elevated while the patient is supine.

tourniquet on and then suddenly dilate

in causing varicos

The patient then stands, and the fillwhen the tourniquet is removed.

�

ities

ing of the varicosities is observed.

Deep and communicating veins are

>

�

involved if the varicosities fill immediately with the tourniquet still on.

�

@

g

""

w

"

�

Table 6-4. Continued

'"

"

N

Test

Indication

Description

Normal Results and Values

Allen's test

To assess the patency

The radial and ulnar arteries are com

The pale and mottled hand that

�

of the radial and

pressed at the level of the wrist

results from arterial compression

ulnar arteries

while the patient clenches his or her

and clenching should resolve in the

§

fist. The patient then opens his or

arterial distribution of either the

�

her hand and either the radial or

radial or ulnar artery, depending on

"

the ulnar artery is released. The

which was released.

�

g

process is repeated for the other

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artery.

o

'"

Homans' sign II-

To detect the pres

The calf muscle is gently squeezed, or

Pain that is elicited with either squeezing

�

ence of deep vein

the foot is quickly dorsiflexed.

or dorsiflexing may indicate a deep

:t

-<

�

thrombosis

vein thrombosis.

�

,...

• A 50% false·posirive rare occurs with this test. Vascular laboratOry studies are more sensitive.

J!

Sources: Data from JM Black, E Matassarin-Jacobs (eds). Luckmann and Sorensen's Medical-Surgical Nursing: A Psycnophysiologic Approach

�

(4th ed). Philadelphia: Saunders, 1993; P Lanzer, J Rosch (eds). Vascular Diagnostics: Noninvasive and Invasive Techniques, Peri·lnterven

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tional Evaluations. Berlin: Springer-Verlag, 1994; and JW Hallet, DC Brewster, RC Darling (cds). Handbook of Patient Care in Vascular Sur

�

gery (3rd ed). Boston: Little, Brown, 1995.

Table 6-5. Noninvasive Vascular Srudies

Tesr

Description

Doppler ultrasound

High-frequency and low-intensiry (1-] 0 MHz) sound waves are applied to the

skin with a Doppler probe (and acoustic gel) CO detect the presence or

absence of blood flow, direction of flow, and flow character over 3neries and

veins with an audible signal. Low-frequency waves generally indicate lowvelocity blood flow,

Color duplex

Velociry patterns of blood flow along witb visual images of vessel and plaque anatscanning or imaging

omy can be obtained by combing ultrasound with a pulsed Doppler derector. Distinctive color changes indicate blood flow through a stenotic area.

Plethysmography

Plethysmography is the measurement of volume change in an organ or body region

'"

(5 types)

(volume change in this context refers CO blood volume changes that represent

Pulse volume recorder (PVR)

blood flow),

Ocular pneumoplerhysmography

PVR and OPG are used

�

CO evaluate arterial flow, whereas WG, PRG, and PPG are used

(OPG)

to evaluate venous flow.

�

-<

Impedance plethysmography (IPG)

Phlebotheography (PRG)

�

Phoroplerhysmography (PPG)

:>

6

; g -<

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"

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