Term
At which vertebra does the abdominal aorta bifurcate? what is an anterior landmark that assists the examiner in estimating where the bifurcation occurs? |
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Definition
adominal aorta bifurcates at the L4,
two cm below umbilicus |
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Term
Know the normal width of the abdominal aorta. Beyond what width is the aorta considered to be aneurysmal? At what rate do aneurysms enlarge? |
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Definition
abdominal aorta is 2cm wide
beyond 3cm wide is considered pathologic
aneurysms enlarge at .5 cm/year
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Term
Differentiate between aneurysms and dissecting aneurysms in terms of frequency in the general population, mechanism and symptoms. |
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Definition
aneurysm - dilation of vessel due to weakness of connective tissue within the media of the vessel wall
Tension = pressure x radius, as tension increases, radius increases
Prevalence - more common than dissecting aneurysm
symptoms: asymptomatic (AAA), lung findings (TAA), chest pain (descending TAA), aortic regurgitation (aneurysms of ascending aorta)
dissectin aneurysms - 2000/year, less than aneurysms
mechanism: tear in the arterial intima allows blood under arterial pressure to enter the arterial wall and dissect along the connective tissue of the media
factors: systemic HTN and medial degeneration are necessary prerequisites
symptoms: excruciating, tearing, anterior chest pain, that may refer to the back; intensification of pain with each heart beat;
loss of pulses, CNS ischemia symptoms; hoarseness, horner's, acute aortic regurgitation
if ascending aortic dissection - > surgury
if descending thoracic -> medically
dissecting aneurysm
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Term
Know where aneurysms are most commonly located. Know which signs and symptoms accompany each of the following aneurysms and why: abdominal aneurysm, ascending thoracic aortic aneurysm, aneurysm of the aortic arch, descending thoracic aortic aneurysm. |
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Definition
From most common to least common:
Abdominal, descending thoracic, ascending aorta, and aneurysm of the aortic arch
abdominal aneurysm - asymptomatic, maybe low back pain, abdominal pain, or signs of embolization to the lower extremities; on exam, expansible (left of midline) and pulsatile mass (below umbilicus)
descending thoracic aortic aneurysm - chest pain and hemoptysis
ascending thoracic aortic aneurysm - aortic regurgitation due to distortion of the aortic annulus and the separation fo the aortic valve cusps
aneurysm of the aortic arch - dyspnea, hoareseness, cough, hempotysis, and anterior or posterior chest pain; palpable up and down movement of trachea with each heart beat (tracheal tug) - depression of the left mainstem bronchus by the aneurysm |
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Term
Describe the mechanism of sudden arterial occlusion. Name two common vascular lesions that give rise to this condition and know the commonly associated symptoms and signs. |
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Definition
sudden arterial occlusion - atherosclerotic plaque dislodging from vascular system and migrating downstream as an embolus to occlude a sdistal vessel within one of the lower extermities
emboli can come from...
1. mural thrombi in the heart (most)
2. atherosclerotic plaque lining the wall of a large artery (aorta)
symptoms and signs (5 P's)
1. Pain
2. Pallor of involved limb
3. Pulses diminished
4. Paresthesias (tingling)
5. Paralysis
6. Gangrene or infarction (necrosis) |
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Term
Describe the physical findings in a patient with chronic arterial occlusion. |
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Definition
physical findings assoc. with chronic arterial occlusion
intermittent claudication - crampy muscle pain that develops in a limb during exercise (walking) as a result of ischemia. Can also be fatigue in lower limb, instead of pain with walking
pain worsens with exercise, gets better upon discontinuation of exercise. However if rest pain occurs, then it's almost entirely occluded
Most often the calf muscle claudication occurs, since the superficial femoral artery is most affected.
If buttocks claudication occurs, then obstruction in aorta
if thigh claudication occurs, then obstruction in iliac arteries
Erectile disfunction (vasculogenic impotence) can occur with claudication - Leriche's syndrome - bilateral aort-iliac occlusive disease -> paralysis of L1; expect claudication in buttocks/thighs
physical findings:
absense of bilateral pedal pulses
trophic changes - thickened toe nails, loss of hair on dorsal surface of feet, thinning and increased shininess of skin over the involved distal limb
cutaneous ulcerations at/below the level of malleoli - highly specific (since above is venous)
limb bruits (highly specific) -
pallor or cyanosis - pallor occurs when limb is above heart level;
delayed capillary filling > 5 secdonds
atrophy of calf muscles
systolic bruits - involved arteries
ankle/branchial index BP < .97 (.5-.8)
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Term
Explain the mechanism responsible for the color changes of Raynaud's phenomenon. |
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Definition
White -> Blue -> Red
(minutes to hours)
pallor - vasospasm - cold or emotional distress
cyanotic - oxygen desaturation from sluggish blood flow within the constricted arterioles
red - vasodilation - pain in digits |
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Term
What is the common final pathway of the thoracic outlet syndromes? What are some typical symptoms of these syndromes? |
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Definition
compression of the subclavian artery and brachial plexus due to
1. Anterior scalene muscle - can compress subclavian artery and brachial plexus bet. the anterio and middle scalene; (+) for adson's maneuver (hold deep breath, turn head toward affected side, lose radial pulse)
2. coracoid process - raise patient's arm, lose radial pulse
3. first rib and clavical - hands in back pockets - lose radial pulse
4. cervical rib - adson's maneuver + xray
symptoms include: pain in the shoulder and arm, numbness and tingling in the arm after elevation of arm above the head), muscle atrophy
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Term
Understand the mechanism responsible for a subclavian steal syndrome. |
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Definition
subclavian steal - narrowing of the subclavian artery proximal t othe origin of the vertebral artery may result in the uncommon situation where exercise of the upper limb steals blood via retrograde flow of the vertebral artery from the unaffected subclavian artery => CNS ischemic symptoms |
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Term
Understand the role of the Allen test in clinical medicine. |
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Definition
Allen test is used to access the patency of the radial artery. |
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Term
Know the three common risk factors for the development of deep vein thrombosis. Explain the mechanism by which each of these factors increases the risk of DVT. |
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Definition
Three common risk factors for development of deep vein thrombosis are...
(1) Venous stasis
(2) Endothial damage (secondary to trauma - e.g. hip fracture, surgery)
(3) hypercoagulability (malignancy, surgery, pregnancy) |
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Term
Describe the common signs and symptoms of DVT. With what degree of specificity can the diagnosis of DVT be made based solely on physical exam? |
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Definition
signs/symptoms of DVT
pain/swelling of lower extremety
localized tenderness along course of deep venous system
pitting edema
superficial venous distention
indivudal physical findings cannot be relied upon solely, must be combined with ultrasound to confirm |
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Term
Understand the mechanism of chronic venous insufficiency. |
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Definition
chronic venous insufficiency - reverse flow due to incomponent valves, as a result of involvement with venous thrombosis;
assoc. with varicose veins, leg pain and swelling, statis dermatitis = brawny induration, venous ulcers, edema |
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