[Exam 1] Chapter 30: Assessment and Management of Patients with Vascular Disorders & Problems of Peripheral Circulation (Page 841-861, 868-880) Flashcards
Conditions of vascular system include
arterial disorders, venous disorders, lymphatic disroders, and cellulitisi.
The vascular system consists of two interdependent systems.. what do these do?
Right side of heart pumps blood through the lungs to the pulmonary circulation
Left side of heart pumps blood to all other body tissues through the systemic circulation
What do arteries and veins do?
Arteries carry blood from left side of heart to tissues. Veins carry deoxygenated blood from the tissues to the right side of the heart
Capillary vessels connect the
arterial and venous sytems
Lymphatic vessels transport what and to where?
TRansport lymph and tissue fluids from the interstitial space to systemic veins
Layers of artereis?
Intima (inner endothelial cell layer
Media (middle layer of smooth muscle and eleastic tissue
Adventitia (outer layer of CT)
The intima provides a smooth surface for contact with
the flowing blood
Media composed chiefly of
elastic and connective tissue fibers that give the vessels considerable strength , allowing constriction and dilation
What are arterioles known as?
REsistance vessels, because they offer resistance to blood flow by altering their diameter
Capillaries composed of
a single layer of endothelial cells because they lack msooth muscle
Capillaries thin walled structure permits
rapid and efficient transport of nutrients to the cells and removal of metabolic wastes
Capillary beds in fingertips contain arteriovenous anastomoses through which blood passes directly from teh arterial to teh venous systems . What are these believed to do?
Regulate heat exchange between the body and the external environment
Veins are referred to as what type of vessel?
Capacitance because of the abaility for large volume of blood to remain in the veins under low pressure
How much of total blood volume contained in veins?
75%
What does the sympathetic nervous system do to the veins?
Causes the veins to constrict, thereby reducing venous volume and increasing the volume of blood in general circulation
Veins: Contraction of skeletal muscles in the extremities creates
the primary pumping action to facilitate venous blood flow back to the heart
Some veins have one-way bicuspid valves in the lower extremities which prevents
blood from seeping backward as it is propelled toward the heart
What are Lymphatic Vessels?
Complex neetwork of thin-walled vessels similar to the blood capillaries. Collects lym fluid from tissues and organs and transports fluid to venous circulation
Lymphatic vessels converge into
two main structures, thoracic duct and right lymphatic duct
Lymphatic Vessels: Thoracic and Right Lymphatic Duct empty into
subclavian and the internal jugular veins .
Right conveys for head, neck, and upper arms. Thoracic does rest of body
If the blood vessels fail to dilate in response to the need for increased blood flow, what happens?
Tissue ischemia (deficient blood supply to a body part) results.
What side of the heart does blood exit from
Left side
What causes the unidirectional flow of blood that occurs?
Pressure difference that exists between the arterial and venous systems.
Because artial pressure is greater than venous, fluid flows from higher to lower pressure (arterial to venous)
Turbulent blood flow creates an abnormal sound called
a bruit, which can be heard with a stethoscope
Capillary Filtration and Reabsorption: Fluid exchangeacross the capillary wall is
continuous
Capillary Filtration and Reabsorption: Hydrostatic force is a driving pressure that is generated by
the lood pressure
Capillary Filtration and Reabsorption: What is osmotic pressure?
Pulling force created by plasma proteins.
Capillary Filtration and Reabsorption: High pressure at the arterial end of the capillaries tends to
drive fluid out of the capillary and into the tissue space
Capillary Filtration and Reabsorption: Osmotic pressure tends to pull fluid
back into the cappillary from the tissue space, but this osmotic force cannot overcome high hydrostatic pressure at the arterial end
Capillary Filtration and Reabsorption: However at the venous end of the capillary, osmotic force predominates over the low hydrostic pressure, and there is a net
reabsorption of fluid from teh tissue space back into the capillary
Capillary Filtration and Reabsorption: Under certain abnormal conditions, fluid filtered out of capillaries may greatly exceed the amounts
reabsorbed and carreid away by the lymphatic vessels. Results in damage to capillary walls and subsequent increased permeability, obstruction of lymphatic drainage.
Capillary Filtration and Reabsorption: Accumulation of excess intersitial fluid results from these proccesses called
edema
Hemodynamic Resistance: Most important factor that determiens resistance in vascular system is
the vessel radius
Hemodynamic Resistance: Peripheral vascular resistance is the opposition to
blood flow provided by the blood vessels
Hemodynamic Resistance: A large increase in hematocrit may increase
blood viscosity and reduce capillary blood flow
Peripheral Vascular Regulating Mechanisms: What is the most important factor in reguating the caliber and therefore the blood flow of peripheral blood vessels?
Sympathetic nervous system
Peripheral Vascular Regulating Mechanisms: All blood vessesls are innervated by the
sympathetic nervous system except the capillary and precapillary sphincters
Peripheral Vascular Regulating Mechanisms: Stimulation of the sympathetic nervous syste causes
vasoconstriction
Peripheral Vascular Regulating Mechanisms: What is responsible for sympathetic vasoconstriction?
Norepinephrine. Occurs in response to physiolgoic and psychological stressors
Peripheral Vascular Regulating Mechanisms: What does Epinephrine do?
Acts like norepinephrine in constricting peripheral blood vessels in most tissue beds. In low concentrations however, causes vasodilation in skeletal muscles of heart.
Inadequate peripheral blood flow occurs when
the heart’s pumping action becomes inefficient. Left-sided heart failure causes an accumulation of blood in the lungs and reduction in forward flow or cardiac output.
Peripheral Vascular Regulating Mechanisms: Right sided heart fialure causes
systemci venous congestion and a reduction in forward flow
Alterations in Blood and Lymphatic Vessels: Decreased venous blood flow results in
increased venous pressure, a subsequent increase in capillary hydrostatic pressure, net filtration out of a capilary into interstitial space
Circulatory Insufficiency of the Extremities: Although many types of peripheral vascular diseaes exist, most result in and produce these symptoms
Ischemia , and produce symptoms like pain, skin changes, diminished pulse, possible edema
Circulatory Insufficiency of the Extremities: Peripheral vascular disease is categorized as
arterial, venous, or lymphatic
Assessmenet of the Vascular System - Health History: a muscular , cramp-type pain , discomfort, or fatigue in teh extremities consistently reproduced with the same degree of exercise or activity and relieved with rest is experienced in patients with
peripheral arterial insufficiency. This pain is known as Intermittent Claudication
Assessmenet of the Vascular System - Health History: Intermittent Claudication is caused by
inability of the arterial system to provide adequate blood flow to the tissues in the face of increased demands for nutrients
50% of arterial lumen or 75% of cross-secctional area must be obstructed before this happens
Assessmenet of the Vascular System - Health History: Persistent pain in the forefoot when the patient is resting indicates
a severe degree of arterial insufficiency and a critical state of ischemia. This is known as rest pain
Assessmenet of the Vascular System - Health History: Rest pain is often worse at
night and may interefere with sleep .
Extremity must be lowered to a dependent position to improve perfusion
Assessmenet of the Vascular System - Health History: The site of arterial disease can be deduced form the location of claudication because pain occurs in muscle groups…
distal to the diseased vessel
Assessmenet of the Vascular System - Health History: Calf pain may accompany reduced blood flow through the
superficial femoral or popliteal artery
Assessmenet of the Vascular System - Health History: Pain in the hip or buttock may result from reduced blood flow in the
abdominal aorta or comon iliac
Assessmenet of the Vascular System - Physical Assessment: What is important in the diagnosis of arterial disorders?
Through assesment of patients skin color and temperature and character of peripheral pulses
Assessmenet of the Vascular System - Physical Assessment: Inadqueate blood flow results in
cool and pale extremities. Further reduction occurs when extremity elevated
Assessmenet of the Vascular System - Physical Assessment: What is Rubor?
A reddish-blue discoloration of the extremities that may be observed 20 seconds to 2 minutes after the extremity is placed in the dependent positon
Assessmenet of the Vascular System - Physical Assessment: Rubor suggests
severe peripheral arterial damage in which vessels that can not constrict remain dilate
Assessmenet of the Vascular System - Physical Assessment: To prevent palpating your own pulse, examiner should use
light touch and avoid using only the index finger for palpitation because this finger has the strongest arterial pulsation of all the fingers. Thumb for the same reason
Assessmenet of the Vascular System - Physical Assessment: Absence of pulse may indicate
that the site of stenosis (narrowing or constriction) is proximal to that location
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: This can be used when
pulses cannot be reliable palpated. Used to detect blood flow in vessels
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Signals are reflected by
the moving blood cells and are received by the device . Then transmitted to loudspeaker where it can be heard
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: The lower the frequency, the
deeper the tissue penetration
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: To evaluate the lower extremities, the patient is placed in the
supine postion with HOB elevated 20-30 degrees. Legs externally rotated to access medial mallelous. Gel applied.
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Tip of Doppler transducer positioned at what degree
45-60 degrees
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Continuous Wave Doppler is more useful as a
clinical tool when combined with ankle blood pressures
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: What is ABI?
Ratio of the systolic blood pressure in the ankle to the systolic blodo pressure in the arm.
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: In ABI, increasing degrees of arterial narrowing, there is a progressive decrease in
systolic pressure distal to the involved sites
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: First step to determine the aBI is to have the patient
rest in supine position for 5 minutes as cuff aplied to ankle. Systolic pressures obtained while listening to doppler.
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Doppler Ultrasonography is used to measure
brachial pressures in both arms. Arms elevated because patient may have asymptomatic stenosis in the subclavian artery
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: To calculate ABI, highest ankle systolic pressure is divided by
the higher of the two brachial systolic pressures
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: In general, systolic pressure in the ankle of a healthy person is the same or slightly higher than the
brachial systolic pressure resulting in ABI of about 1.0
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Nurse should perform baseline ABI on any patient with
decreased pulses or any patient 70 years or older
Assessmenet of the Vascular System - Diagnostic Evaluation, Doppler Ultrasound Flow Studies: Prior to ABI, patients should be instructed to
avoid use of tobacco or caffeinated beverages for at least 2 hours before testing
Assessmenet of the Vascular System - Diagnostic Evaluation, Exercise Testing: Used to determine
how long a patient can walk and to measure the ankle systolic blood pressure in response to walking
Assessmenet of the Vascular System - Diagnostic Evaluation, Exercise Testing: Most patients can complete the test unless they have
severe cardiac, pulmonary, or orthopedic problems or a physical disability
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: What does this involve??
B-Mode grayscale imaging of the tissue, organs and blood vessels and permits estimation of velocity changes by use of a pulsed DOppler.
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: Color flow techniques may be used to
shorten the examination time
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: May be used to determrine
the level and extend of venous disease as well as chronicity of the disease
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: Using B mode and doppler, it is possible to image and assess
blood flow, evaluate flow of the distal vessels, locate the disease and determine anatomic morphology and hemodynamic significant of plaque causing stenosis
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: Prep for test?
It is non invasive and requires no patient prep.
Assessmenet of the Vascular System - Diagnostic Evaluation, Duplex Ultrasonography: Patients who undergo abdominal vascular duplex ultrasound prep
NPO for at least 6 hours prior to the examination to decrease production of bowel gas that cna interfere with the examination
Assessmenet of the Vascular System - Diagnostic Evaluation, Computed Tomography SCanning (CT): This provides
cross-sectional images of soft tissue and visualizes the area of volume changes to an extremity and the compartment where changes take place
Assessmenet of the Vascular System - Diagnostic Evaluation, Computed Tomography SCanning (CT): What happens in Multidetector-computed tomography (MDCT),
a spircal CT scanner and rapid intravenous infusion of contrast agent are used to image very thin sections of the target area and results are configured in three dimensions so that the image can be rotated and viewed from multiple angles
Assessmenet of the Vascular System - Diagnostic Evaluation, Computed Tomography SCanning (CT): In MDCT< patient is exposed to
xrays and a contrast agent to visualize the blood vessels
Assessmenet of the Vascular System - Diagnostic Evaluation, Computed Tomography SCanning (CT): Patients with impaired renal function scheduled fo rMDCT may require
preprocedural treatment to prevent contrast induced nephropathy. This may include oral or IV hydration 6-12 hours before preprocedure
Assessmenet of the Vascular System - Diagnostic Evaluation, Computed Tomography SCanning (CT): In MDCT, nurse should montior
the patients urinary output post procedurally.
Assessmenet of the Vascular System - Diagnostic Evaluation, Angiography: Arteriogram produced by this may be used to confirm diagnosis of occlusive arterial disease… this involves what?
Injecting a radiopaque contrast agent directly into the arterial system to visualize the vessels
Assessmenet of the Vascular System - Diagnostic Evaluation, Angiography: What does the patient experience when contrast agent injected
Temporary sensation of warmth and local irritation may occur at the injection site
Assessmenet of the Vascular System - Diagnostic Evaluation, Angiography: Manifestations include
dyspnea, nausea , and vomiting, sweating, tachycardia, and numbness.
May require antihistamines or corticosteroids
Assessmenet of the Vascular System - Diagnostic Evaluation, Magnetic Resonance Angiography: MRA performed with MRI scanner to isolate
blood vessels. Resulting images can be rotated and viewed from multiplea angles
Assessmenet of the Vascular System - Diagnostic Evaluation, Magnetic Resonance Angiography: MRA contraindicated in patients with any
metal implants or devices like pacemakers.
Assessmenet of the Vascular System - Diagnostic Evaluation, Magnetic Resonance Angiography: Patient should beinstructed that they may hear
noises including banging and popping sounds.
Assessmenet of the Vascular System - Diagnostic Evaluation, Magnetic Resonance Angiography: MRA procedure require the use of
IV dyes. Therefore nursing implications following MRA same as MDCT
Assessmenet of the Vascular System - Diagnostic Evaluation, Contrast Phlebography (Venography): What does this involve?
Injecting a radiopaque contrast agent into the venous system.
Assessmenet of the Vascular System - Diagnostic Evaluation, Contrast Phlebography (Venography): If thrombus exists, X-Ray reveals
unfilled segment of vein in an otherwise completely filled vein
Assessmenet of the Vascular System - Diagnostic Evaluation, Contrast Phlebography (Venography): Injection of contrast may cause beief but painful
inflammation of the vein
Assessmenet of the Vascular System - Diagnostic Evaluation, Contrast Phlebography (Venography): What is the standard for diagnosing lower extremity venous thrombosis?
Duplex Ultrasonography
Assessmenet of the Vascular System - Diagnostic Evaluation, Contrast Phlebography (Venography): What should patient know before receiving contrast?
He or she will receieve dye through a vein and will be monitored for 2 hours post venogram
Assessmenet of the Vascular System - Diagnostic Evaluation, Lymphoscintigraphy: What does this involve?/
Injection of a radioactively labaled colloid subcutaneously in the second interdigital space. Extremity rthen exercised to facilitate the uptake of the coloid by lymphatic system