Quizzes Before Midterm Flashcards
T or F
Poiseuille’s Law describes the relationship of blood flow to pressure changes, radius of a vessel & the thickness of blood?
true
T or F
Flow always moves from an area of higher pressure to an area of lower pressure
true
T or F:
the hydrostatic pressure in the venous sms is higher than the hydrostatic pressure in the arterial sms while a patient is standing?
false
what happens to blood flow in a vessel that has a stenosis?
Increased pressure gradient across the segment
increased velocity at area of stenosis
the type of flow pattern where the velocities increase toward the center of the vessel is known as?
laminar
The common femoral artery & brachial artery have what type of waveform
High resistance
The common carotid & renal artery always have what type of waveform?
low resistance
these are true about the venous waveforms
Venous waveforms change with respiration
Venous waveforms closest to the heart will have a pulsatile component to them
All lower extremity waveforms are phasic in a normal patient.
In relationship to arteries & veins these statements are true (4)
- arteries have thicker wall then veins
- veins have internal valves
- arteries have a much higher internal pressure
- arteries & veins both have a tunica intima, media & adventitia.
T or F
Venous blood return in the lower extremities is greatest during inhalation?
False.
The upper extremity is greater during inhalation.
T or F
The most common cause in the US of chronic obstructive arterial disease in the upper extremities is artherosclerosis obliterans ?
false
the lower extremitites
T or F Thromboangiitis obliterans (Buerger's) always starts in the distal arteries & progresses centrally?
true
claudication
exercised induced pain caused by lack of adequate blood flow to the legs.
always induced by muscular exertion
always relieved by rest
reproducible & can occur in the calf, thigh or buttock.
rest pain can be relieved by:
standing & hanging legs in a dependent position
All of the following are physical findings that can be associated with obstructive arterial disease of the lower extremities:
skin has a shiny tight appearance
hair loss to the foot
ulcer on the heel
Medial Cald ulcer –> Venous disease
The following are findings associated with subclavian steal syndrome on the left side:
Reversal of flow in the ipsilateral vertebral artery
>20 mmHg pressure drop in the ipsilateral arm
Stenosis of proximal left subclavian artery
The most common site of arterial occlusive disease in the lower extremities is?
distal superficial femoral artery
a 24 male patient who smokes is sent to your lab & presents with symptoms of leg cramps at night. you perform your noninvasive arterial pressure & waveforms & they are normal at rest. What is your conclusion?
the symptoms are most likely not related to a vascular problem.
what is the most vital artery in the lower extremity that serves as one of the main sources of collateralized flow when significant atherosclerotic disease is present?
Profunda femoral artery
List the classic signs of acute arterial obstruction known as the 6 P’s:
- pain
- paralysis
- parathesis
- pallor
- pulselessness
- pokilothermia
the peak systolic blood pressure in an area of a limb distal to a significant obstruction or stenosis will :
will decrease
T or F
A pressure gradient of less than 20 mmHg indicated significant disease at or above the level of the cuff with the lowest pressure?
false
a normal ankle brachial index in a non-diabetic patient is
1.0
An obese diabetic patient is sent to your lab to be evaluated for arterial disease of the lower extremities. when performing their PVR & segmental pressure study you notice that their thigh PVR waveform is in the category 3 (moderate) range but the pressure index at this level is 1.10. how do you explain this?
It could be the result of cuff artifact
the patient could have medial calcinosis.
while reviewing the segmental pressures on a patient you notice that the patient has a right high thigh pressure of 150 and a right low thigh pressure of 90. the patient’s brachial pressure is 140. based on just these finding what level of disease does this patient have?
femoral
T or F
the shape of a PVR waveform holds more value then the amplitude of the waveform?
true
the first component of a PVR waveform that is lost when the presence of arterial disease exists is the :
Dicrotic limb
The analog Doppler signal distal to an area of severe stenosis n the lower extremities should:
be monophasic
have a low pulsatility index
The waveform taken with pulse wave Doppler at an area of an 80% stenosis should have
a focal increase in peak systolic velocity
extensive spectral broadening
A patient is ent to your lab to have his LEA evaluated with depulex. while performing the exam you notice that the velocity at the prox SFM is 80 cm/s. you continues the exam & obtain a pulse wave doppler signal about 1 cm distal to the prox SFA & you get a velocity of 190 cm/s. based just on these findings you can conclude that there is :
a 50-99% narrowing of this bypass.
all of the following are typically abnormal flow patterns in the LE (4)
- monophasic waveform
- waveform with spectral broadening
- turbulent waveform
- tardus parvus waveform
A “Peaked Pulse” waveform is a characteristic waveform for which condition?
Raynaud’s syndrome
Buerger’s Disease
A patient is sent your lab with vague symptoms in the right arm while performing certain excursus. you ask the patient to demonstrate the excersis that cause the symptoms while monitoring her blood flow. you notice theat when she performs the act the PVR waveform of the brachial area goes from category 1 to a 4 & the pressure drops from 120 to 50 mmHg. what is your diagnosis.
Thoracic Outlet Syndrom
T or F
You should get a more than 20% drop is systolic pressure of the digits after cold immersion for a positive Raynaud’s diagnosis?
true.
T or F
When obtaining a pulse wave Doppler signla you should always use a Doppler angle of 60 degrees or less?
true
These are possible pathology of the UEA
Thoracic outlet syndrome
Takayasu’s arteritis
Embolus
Subclavian steal syndrome
a normal spectral waveform of the brachial artery is?
Triphasic & Biphasic
T or F
Spectral broadening is the filling ofthe spectral window caused by turbulent flow & is present in a spectral waveform at an area of stenosis?
true
what type of spectral waveform would you expect to see about one centimeter distal to an area of 90% narrowing within a vessel?
Post-stenotic turbulent
T or F
An artery is considered aneurismal when it increases focally at least one and a half times its normal size?
true
T or F
Arterial venous fistulas have an arterial & nevous anastomosis?
false
An arterial venous fistula is considered mature when: (3)
- the diameter of the draining vein is greater then 4mm.
- The PSV ratio is less than 2
- the flow volume is at least 500 ml/min.
A patient is sent to your lab to have there arterial venous graft evaluated. while scanning you identify it to be a brachial artery to axillary vein graft. you obtain a pulse wave Doppler signla at the venous anastomosis & get a velocity of 460 cm/s, you then proceed to obtain a signal of the outflow vein just 2 cm cephalad from the anastomosis & get a velocity of 120cm/s. this gives you a PSV ratio of 3.8. what is your diagnosis based just on these findings?
there is a 75% narrowing at the venous anastomosis.
T or F
Arterial venous grafts have a higher rate of stenosis, infection & pseudoaneursyms then arterial venous fistulas?
true.
T or F:
Normal perforator veins allow blood to flow from the deep system to the superficial system
false
The distention of the distal veins that occurs when a pateint has venous insufficiency is a result of:
increased hydrostatic pressure
pooling & stasis of blood.
The symptoms that are most commonly associated with venous insufficiency involving the deep system are:
edema
The symptoms that are most commonly associated with venous insufficiency involving the superficial system and perforator veins are:
Edema
Varicosities
Gaitor zone skin changes
ulceration
The symptoms that are most commonly assocaited with venous insufficiency involving the superficial system are:
Varicosities
T or F:
Primary varicosities are a result on insufficiency that started in the deep system & extended into the superficial system by way of the perforator veins.
false
causes of venous insufficiency are:
weak or inactive calf muscle pump
previous DVT
previous SVT
congenital valve defects
a patient that is positive for reflux will have a flow reversal time of:
> .5 seconds
T or F:
In a PPG venous exam of the lower extremities a refull time of less then 20 secs indicates that there is no significant reflux present within the limb.
false
While performing a PPG venous exam on a pt without a tourniquet you obtain an abnormal refill time. in order to determine where the insufficiency is occuring you proceed to apply a tourniquet at the ankle & you get a normal refill time. you proceed & more the tourniquet to jsut below the knee and you a normal refill time again. you proceed once more & move the tourniquet to just above the knee and get a normal refill time. wehre is the patients insufficiency occurring?
Great Saphenous vein.
most deep venous thrombi become established in:
calf
the condition involving an outflow obstruction of the venous system that presents with extreme swelling, cyanosis & reduced arterial inflow is known as:
phlegmasia cerulea dolens
what percent of pulmonary emboli is estimated to have originated in the lower extremities & pelvis?
90%
which location of DVT is more likely to travel to the lung as a pulmonary embolus?
external iliac vein DVT
Common femoral vein DVT
what are the 3 predisposing condition for DVT known as “Virchow’s Triad”
Stasis
Trauma
Hypercoagulation
The 4 major symptoms for DVT are:
Pain
Swelling
Redness
Varicose veins
When the calf muscle pump & venous valves become inadequate at returning blood back to the heart it leads to the pooling of blood in the lower extremities. A condition known as:
Venous Insufficiency
T or F
You can’t determine that a patient has DVT based on clinical symptoms & physical findings alone?
true
T or F
An ascending venogram is used to evaluate for venous insufficiency
false
T or F
After initial treatment of DVT patients are treated with oral anticoagulation to avoid damage to venous valves
false. to prevent reoccurrence.
what are the characteristics of an acute deep vein thrombosis?
dilated
non-compressable
anechoic
what are the characteristics of chronic post-thrombotic scaring:
- wall thickening, partially compressible, bright internal echo’s with shadowing.
- small vein, no flow, large dilated collateral veins.
- normal size, recanalized lumen, collateral veins.
T or F
tail thrombus with motion seen on duplex is the most distal portion of a clot and is always considered acute
true
When determining if a clot is acute or subacute these statements are true: (4)
- as a clot progresses to the subacute stage the vein decreases in size.
- as a clot progresses to the subacute stage the clot increases in echogenisity.
- clot that is anechoic is always acute.
- collateral vein are usually more pronounced in the subacute phase.
difficult to determine stage based on just ultrasound findings alone.
While scanning a patients upper extremity veins you obtain a phasic spectral Doppler waveform within the right subclavian vein & a pulsatile spectral Doppler waveform within the left subclavian vein. what does this suggest?
an obstruction proximal to the right subclavian vein.
Which veins of the upper extremity should have cardiac pulsations coupled with respiratory patterns normally:
- Internal jugular
- Brachiocephalic vein
- subclavian vein
