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
leading cause of disability in the US
CVA
3rd leading cause of death in US
what is a TIA
subset of self-limited ischemic stroke
symptoms resolve in 24hr
TIA’s have 10x greater risk of subsequent stroke
risk for cerebral vascular accidents
inherited - age, Hx of stroke, family Hx, male, black race, sickle cell
modifiable- smoking, HTN, DM, CAD, Afib, HF, HLD,obesity
carotid disease diagnositic testing
angiography - dx vascular obstruction
CT/MRI - ID aneurysms and AVM
Transcranial doppler US - indirect evidence of vacular occlusions
Carotid Auscultation - ID bruits
Carotid US - quantify degree of stenosis
ID - identify
where does carotid stenosis commonly occur
at internal/external carotid bifurcation due to turbulent blood flow at the branch point
workup includes eval for sources of emboli (Afib, HF, valvular vegetation, or paradoxical emboli in the setting of PFO)
when is TPA recommended for CVA
within 4.5 hour if they meet criteria
interventional radiology treatment for CVA
intra-arterial thrombolysis
intravascular thrombectomy *benefits seen up to 8hr after onset of CVA
remvoes clots under fluroscopy
When is a CEA indicated for patients
surgical treatment for severe carotid stenosis (lumen diameter 1.5 mm or >70% blockage
key point slide
what is carotid stenting and risks asscociated with it
alternetive to CEA
major risk of microembolization -> CVA
embolic protection devices to mitigate risks
medical treatment for CVA
antiplatelet therapy
smoking cessation
BP control
cholesterol control
Diet and exercise
minimize risks!
CEA preop eval
neuro eval - establish preop deficts
CV disease - CAD is prevalent in carotid disease (MI major perioperative M&M)
HTN - optimize & look at trend
CPP= MAP - ICP
maintain collateral flow through stenotic vessels especially with cross-clamping
extreme head rotation/ flexion/extension may compres contralateral artery flow :(
cerebral oximetry devices to determine cerebral perfusion
your patient has severe carotid disease and severe CAD… how can you optimize this patietnt for a CEA
stage cardiac revascularization and CEA
most compromised area takes priority
StO2 is effected by
- cerebral oxygenation whcih is effected by
- and cerebral O2 consumption (CRMO2) which is effected by
- MAP, Cardiac Output, SaO2/SpO2, Hgb, PaCO2
- temperature and depth of anesthesia
what is the definition of peripheral artery disease
ankle-branchial index (ABI) < 0.9
ABI = Ratio of SBP @ ankle : SBP @ brachial artery
chronic hypo-perfusion is typically due to
athersosclerosis
may be also due to vasculitis
acute occlusions to are typically due to
embolism
incidence of PVD increases with age
exceeding 70% by age 75
atherosclerosis is systemic and patients with PAD have
3-5x increased risk of MI and CVA
risk factors for PAD
advanced age
family history
smoking
DM
HTN
obesity
increased cholesterol
signs and symptoms of PAD
intermittent claudication
resting extremity pain
decreased pulses
SQ atrophy
hair loss
coolness
cyanosis
*relief with hanging LE overside of bed bc it increases hydrostatic pressures
PAD diagnosis (4)
doppler US: provides a pulse volume waveform identifies arterial stenosis
duplex US: can identify areas of plaque formation & claudification
transcutaneuos oximetry: can assess the severity of tissue ischemia
MRI with contrast angiography:used to guide endovascular intervention or surgical bypass
PAD medical treatmentt
exercise
BP control
cholesterol control
glucose control
medical/surgical intervention for PAD
revascularization indicated with disabling claduication or ischemia
surgical reconstruction - arterial bypass procedure
endovascular repair - transluminal angioplasty or stent placement
acute artery occlusion frequently due to _____ _______
frequently due to cardiogenic embolism
common causes of acute artery occlusion (2)
left atrial thrombus arising from Afib
Left ventricular thrombus arising from dilated cardiomyopathy after MI
Less common - valvular heart disease, endocarditis, PFO, atheroemboli, plaque rupture, hypercoagulability, trauma
s/s of acute artery occlusion
limb ischemia, pain/parasthesia, weakness, decreased peripheral pulses, cool skin, color changes distal to occlusion
Diagnosis and treatment of acute artery occlusion
diagnosis: arteriography
treatment: surgiacl embolectomy, anticoagulation, amputation (last resort)
what is subclavian steal syndrome?
what is the treatment?
occluded SCA proximal to vetebral artery causing veterbral artery blood flow to be diverted away from brainstem
treatment: SC endarterectomy is curative
risk factors for subclavian steal syndomre
atherosclerosis, Takayasu Arteritis, aortic surgery
raynaud’s phenomenon
episodic vasospastic ischemia of the digits
effects women> men
Primary and secondary causes of raynauds
rheumatic disease
drugs/toxins - BB, cocaine, tobacco
endocrine disease
trauma
arterial disease
hemothologic disorders
neoplasma - ovarian cancer
May also appreat with CREST syndrome (scleroderma subtype)
symptoms
diagnosis
treatment
of raynauds
digital blanching or cyanosis with cold exposure or SNS activation
dx: based on H&P
treatment:
protection from cold, CCB, alpha- blockers, surgical sympathectomy for severe ischemia
common peripheral venous diseases processes that occur during surgery (3)
superficial thombophelbitis
deep vein thrombosis
chronic venous insuffiency
DVT may lead to PE and leading cause of periop M&M
virchows triad that predispose to venous thrombosis
- venous stasis
- hypercoagulability
- disrupted vascualr endothelium
risk factors for thromboembolism
what surgery results in a superficial thrombophelbitis and DVT in surgey
50% total hip replacements
*normally subclinical and completely resolve
DVT is associated with extremity pain and swelling
what are the risk factors
age > 40
surgery > 1hr in duration
cancer
ortho surgery on pelvis and low extremities
abdomnial surgery
doppler US is senstive in detecting proximal or distal thrombosis
proximal
venography and impedance plethysmograpgy are also useful
prophylatic measures for DVT
SCDs, SQ heparin 2-3x/day, regional anesthesia to promote early ambulation
DVT treatment
anticoagulation: warfarin + Heparin or LMWH
PO anticoags for 6 moinths or longer
IVC filter for recurrent PE or CI to anticoags
Heparin is DC’d when Warfarin achieves therapeutic effect (INR 2-3)
systemic vasculitis
Diverse group of vascular inflammatory diseases with characteristics that are often grouped by the size of the vessels at the primary site of the abnormality
Additionally,vasculitis can be a feature of connective tissue diseases such as systemic lupus erythematosus and rheumatoid arthritis
Large-artery vasculitis includes:
Takayasu arteritis
Temporal (or giant cell) arteritis
Medium-artery vasculitis includes:
Kawasaki disease, which is most prominently the coronary arteries
Medium tosmall-artery vasculitis includes:
thromboangiitis obliterans
Wegener granulomatosis
polyarteritis nodosa
temporal (giant cell) arteritis
inflammation of the arteries of the head and neck
symptoms: unilateral headache, scalp tenderness, jaw claudication
Opthalmic Arterial branches may lead to ischemic optic neuritis and unilateral blindness
treatment and diagnosis of temporal (giant cell) arteritis
Tx: Prompt initiation of corticosteroids indicated for visual symptoms, to prevent blindness
Dx: Biopsy of temporal artery shows arteritis in 90% of pts
Thromboangiitis Obliterans “Buerger Disease”
Inflammatory vasculitis leading to small & medium vessel occlusions in the extremities
Autoimmune response triggered by nicotine
Tobacco use is most predisposing factor
5 diagnostic criteria for Thromboangiitis Obliterans “Buerger Disease”
h/o smoking
onset before age 50
infrapopliteal arterial occlusive dz
upper limb involvement
Absence of risks factors for atherosclerosis (outside of tobacco)
Diagnosis confirmed w/biopsy of vascular lesions
Symptoms of Thromboangiitis Obliterans “Buerger Disease” (4)
- forearm, calf, foot claudication
- Ischemia of hands & feet
- Ulceration and skin necrosis
- Raynaud’s is commonly seen
Thromboangiitis Obliterans “Buerger Disease” treatment (3)
Smoking cessation-most effective tx
Surgical revascularization
No effective pharmacological tx
Anesthesia implications
for Thromboangiitis Obliterans “Buerger Disease”
Meticulous positioning/padding due to poor perfusion
Avoid cold; Warm the room and use warming devices
Prefer non-invasive BP and conservative line placement
Polyarteritis Nodosa is an antineutrophyl cytoplasmic antibody (ANCA) negative vasculitis associated with _____ and involves what type of arteries
what does the inflammation lead too
w/ Hep B, Hep C, or Hairy Cell Leukemia
Small & medium arteries involved
Inflammation results in glomerulonephritis, myocardial ischemia, peripheral neuropathy and seizures
HTN generally caused by renal dz
Renal failure is primary cause of death
treatment for Polyarteritis Nodosa and anesthesia implications
Tx: steroids, cyclophosphamide, treating underlying cause (s/a cancer)
Anesthesia Implications: consider coexisting renal and cardiac disease, HTN
Steroids likely beneficial
what causes Lower Extremity Chronic Venous
Long standing venous reflux & dilation
Effects 50% of the population
Ranges mild-severe
Mild sx: telangiectasias, varicose veins
Severe sx: edema, skin changes, ulceration
Risk factors for Lower Extremity Chronic Venous Disease
advanced age
family hx
pregnancy
ligamentous laicity
previous venous thrombosis
LE injuries
prolonged standing
obesity
smoking
sedentary lifestyle
high estrogen levels
diagnositc criteria Lower Extremity Chronic Venous Disease
Sx of leg pain, heaviness, fatigue
Confirmed by ultrasound showing venous reflux
Retrograde blood flow > 0.5 seconds
the initial conservative
treatment for lower extremity chronic venous insufficiency
Leg elevation
Exercise
Weight loss
Compression therapy
Skin barriers/emollients
Steroids
Wound management
conservative medical management for lower extremity chronic venous disease
Diuretics
Aspirin
Antibiotics
Prostacyclin analogues
Zinc sulphate
*If management fails, ablation may be performed
ablation for chronic venous disease methods, indications, contraindications
ascending dissection
catastrophic, requires emergent surgical intervention
Standfor A, Debakey 1/2
mortality increases 1-2% per hour
overall mortality 27-58%
overview of treatment for aortic dissection
Standford A - emergent surgery
Standford B - rarely treated with urgent surgert
*uncomplicated type B = BP control BB, Aline
impending rupture = surgical treatment
subclavian steal syndrome symptoms
syncope, vertigo, ataxia, hemiplegia, ipsilateral arm ischemia
*effected arm SBP may be ~20 mmHg lower
*Bruit over SCA
surgical intervention for low extremity chronic venous disease
usually last resort
