Vascular Flashcards
what the 3 main arterial pathologies
aneurysms, dissections, occlusions
what vessel is most affected by aneurysms and dissections
aorta and its branches
which vessel is more likely to be affected by occlusions
peripheral arteries
aortic aneurysm is the dilation of _____ layers of artery causing a _____% increase in diameter
aortic aneurysm is the dilation of 3 layers of artery causing a >50% increase in diameter
what are symptoms of aortic anuerysm
asymptomatic or pain due to compression of surrounding structures
treatment of aortic aneursyms
initially treated medically to decrease expansion rate
- manage BP, cholesterol, stop smoking
- avoid strenuous exercsie, stimulants, stress
- regular monitoring for progression
- surgical when >5.5 cm diameter, growth >10 mm/year, and family Hx of dissection
aortic aneursyms rupture is associated with 75% mortality rate
2 types of aneurysms
fusiform - uniform dilation along entire circumference of arterial wall
saccular - berry shapped, bulge to one side
diagnostics for aortic aneurysm
CT, MRI, CXR, angiogram, echocardiogram
what is the fastest/safest way to obtain a diagnosis of aneursym in suspected dissection
doppler echocardiogram
what is an aortic disection
tear in the intimal layer causing blood to enter medial layer
symptoms of aortic dissection
severe sharp pain in posterior chest or back
diagnosis of aortic dissection
stable: CT, CXR, MRI, angio
unstable: ECHO
Standford A DIssection
ascending aorta: all patietns with acute dissection involving the ascending aorta should be considered candidates for _____
ascending aorta: all patietns with acute dissection involving the ascending aorta should be considered candidates for surgery
Standford A Dissection
the most commonly performed procedures:
ascending aorta & aortic valve replacement with a composite graft
replacement of the ascending aorta and resuspension of the aortic valve
Standford A Dissection
in the resection of the aortic arch with a standford A aortic dissection what surgical intervention is required
surgery requires cardiopulmonary bypass, profound hypothermia, and a period of circulatory arrest
Standford A Dissection
with current techniques for aortic arch resection, a period of circulatory arrest of _ - __ minutes at a body temp of ___- ____ C can be tolerated
with current techniques for aortic arch resection, a period of circulatory arrest of 30-40 minutes at a body temp of 15-18C can be tolerated
Standford A
what is the major complication of aortic arch replacement
neuro deficits
occurs in 3-18% of patients,
appears that selective antegrade cerebal perfusion decreases but does not completely eliminate the mobidity and mortality associated with the procedure
Standford B/Debakey 3
patietns with an acute, but uncomplicated type B aortic dissection with normal hemodynamics, no periaortic hematoma, or branch vessel involvement can be treated with
medical therapy
Standford B DIssection/DeBakey 3
medical therapy consists of
intraarterial monitoring of SBP and UOP
drugs to control BP and the force of LV contraction
BB, Cardene, Sodium NItroprusside
surgery is indicated for patients with type B aortic dissection who have signs of
impending rupture (persistent pain, hyoptension, L-sided hemotrhorax); ischemia of legs, abdominal viscera, spinal cord and/or renal failure
risk factors for aortic dissection
HTN, atherosclerosis, aneurysm, family hx, cocaine use, and inflammatory disease
inherited diseases at risk for aortic dissection
marfans, ehlers Danlos, bicuspid aortic valve, non-syndrome family hx
cause of aortic dissection
blunt trauma, cocaine, iatrogenic (medical treatment)
* cardiac catherization, aortic manipulation, cross clamping, arterial incision
when is dissection most common
men and pregnant women in 3rd trimester
aortic aneursym rupture triad of symptoms
hypotension
back pain
pulsatile abdominal mass
where do most abdominal aortic aneursysms rupture
left retroperitoneum
how can exsanguination be prevented in aortic aneursym rupture
clotting and the tamponade effect in the retroperitoneum accumulation of blood
why might euvolemic resusictiation be deferred until the rupture is surgically controlled
resulting increase in BP without control of bleeding may lead to loss of retroperitoneal tamponade and further bleeding -> hypotension -> death
suspected Standford A- abdominal aortic aneursysm POC
immediate operation without preoperative testing or volume resuscitation
4 causes of mortality realted to surgeries of thoracic aorta
MI
repsiratory failure
renal failure
stroke
assess ECHO, presence of CAD, valve dysfunction
what preoperative evaluation findings might preclude a pt from an elective AAA resection
severe reduction in FV1 or renal failure
smoking/COPD are predictors of post-aortic surgery…
respiratory failure
PFTs and ABGs help define risk
consider preop bronchodilators, ABX, chest physiotherapy
preop renal dysfuncftion is the most important indicator of post aortic surgery renal failure what are some considerations to prevent worsening renal function
preop hydration
avoid hypovolemia, hypotension, low cardiac output
avoid nephrotoxic drugs
avoid intraop AKI
h/o of stroke or TIA preop considerations
carotid ultrasound
angiogram of brachiocephalic and intracranial arteries
severe carotid stenosis shold have what before elective surgery of an aneurysm
recommended CEA
Anterior spinal artery syndrome
caused by lack of blood flow to the anterior spinal artery
anterior spinal artery responsible for perfusing anterior 2/3 of cord
ischemia from anterior spinal artery syndrome can lead to
loss of motor function below infarct
diminished pain and temperature sensation below the infarct
autonomic dysfuncion leading to hypotension and loss of bowel and bladder
why is the anterior spinal artery the most common spinal cord ischemia problem
minimal collateral perfusion
posterior spinal cord has 2 posterior arteries allowing for collateral
common causes of anterior spinal artery syndrome
aortic aneursyms, aortic dissection, atherosclerosis, trauma
CVA division between ischemic and hemorrhagic percentages
ischemic - 87%
hemorrhagic - 13%
sudden onset of neuro deficit
what is a big predictor of CVA
carotid disease