Vascular Flashcards
What is the triad of aortic aneurysm rupture?
Hypotension
Back pack
Pulsatile Abdominal Mass
Where do most aortic abdominal aneurysms rupture?
Left retroperitoneum
Though hypovolemic shock can be present, how can exsanguination in aortic aneurysm rupture?
clotting and the tamponade effect in the retroperitoneum
Why would you defer euvolemic resuscitation until the rupture is controlled?
because it can result in an increase in BP without control of bleeding which may lead to loss of retroperitoneal tamponade leading to further HYPOTENSION, bleeding, and death
Unstable Aortic Aneursym require immediate..
operation without preop testing or volume resuscitation
What are the 4 primary causes of mortality related to surgeries of thoracic aorta
MI
Resp failure
Renal Failure
Stroke
Aortic Aneurysm Resection Preop
_____ may require intervention prior to surgery
Ischemic heart disease
Cardiac eval test: stress test, echo, radionuclide imaging
What may preclude (prevent) a patient from having AAA resection?
SEVERE reduction in FEV1 or renal failure
What are predictors of post aortic surgery respiratory failure ?
Smoking
COPD
Use PFT and ABG to define risk
**consider brochodilators, ABX, or chest physiotherapy
AAA rupture
Preop renal dysfunction is the most important indicator of post-aortic surgery renal failure
Make sure to
PreOp hydration
Avoid hypovolemia, Hypotension, low cardiac output
No nephrotoxic drugs
Preop Eval for AAA
what if they had a history of stroke or TIA
Obtain a-___
carotid ultrasound
Angiogram of brachiocephalic and intracranial arteries
Preop Eval AAA
What if they have severe cartodi stenosis?
recommend work up for CEA
Carotid endarterectomy
Anterior Spinal Artery Syndrome Patho
lack of blood flow to the anterior spinal artery
anterior spinal artery responsible perfusing 2/3 of spinal cord
What does ischemia to the anterior spinal artery lead to
loss of motor function below the infarct
diminished pain and temp sensation below the infarct
autonomic dysfunction
leading to hypotension and loss of bowel and bladder
why is anterior spinal artery syndrome the most common form of spinal ischemia?
because the anterior spinal artery has minimal collateral perfusion thus its very vulnerable
- The posterior spinal cord has 2 spinal arteries
Common causes for ASA syndrome
Aortic aneurysm, aortic dissection, atherosclerosis, trauma
CVA percentage
87 ischemic
13 hemorrhagic
**sudden osent of neuro defecits
What is the prominent predictor of CVA
Carotid disease
CVA is the 1st leading ___
cause of disability in US
3rd leading cause of death
What is a TIA?
subset of self limited ischemic strokes
How long do TIAs take to resolve
24 hours
Carotid Diagnostic Test
Angiography to diagnose vascular occlusion
TIAS have a ____greater rx of subsequent strokes
10
What can identify both carotid disease and aneurysms, and AMV
CT and MRI
Cartoid Dx
What diagnostic may give you indirect evidence of vascular occulusions with rela time bedside monitoring?
transcranial doppler US
Carotid DZ
Diagnostic to identify bruits?
Carotid Auscultation
Cartoid DZ
Carotid Ultrasound can idenitfy___
degree of carotid stenosis
Where does cartoid stenosis usually occur?
at the internal and external carotid birufication due to turbulent blood flow at the branch point
Carotid DZ
Work Up Includes
evaluation for sources of emboli s/a Afib, heart failure, valvular vegetation, or paradoxical emboli in the setting of PFO (patent foramen ovale)
Treatment for CVA
TPA within 4.5 hours
Interventional radiology
-Intraarterial thrombolysis
-Intravascular thrombectomy
Carotid Endartectomy ( CEA)
Carotid Stenting
alternative to CEA
when can you see the benefits of a CVA after an intravascular thrombectomy
8 hours
(measurements)When is CEA indicated
LUMEN diameter 1.5 mm or greater than 70 percent blockage
Whats the major risk to carotid stenting
MICROEMBOLI - CVA
Ongoing Medical Treatment of CVA
Antiplatelet
Smoking cessation
BP control
cholesterol
Diet and physical activity
CEA Preop
Neuro eval - for defecits
htn COMMON * estabilish acceptable BP to optimize CPP ( MAP - ICP_
What is CV dz prevelant with carotid stenosis
CAD
What is a major cause of perioperative mortality and mobidity in CEA
MI
CEA during surgery
Maintain collateral blood flow through stenotic vessel
**Extreme head rotation/flexion/extension may compress contralateral artery flow
***Cerebral Oximetry Devices
Clinical Dilemma: Severe Carotid Disease + Severe CAD
Must stage cardiac revascularization and CEA
**most compirsed area should take priority
Cerebral 02 consumption effected by:
Temperature
Anesthesia
Cerebral Oxygenation effected by:
MAP
COP
Sa02
HGB
PaC02
Peripheral Artery Disease
Results in compromised blood flow to the extremities
Peripheral Artery Disease is defined by an ankle- brachial index of
ABI less than 0.9
ABI is a ratio of SBP at tthe
ankle to the brachial artery
PAD
Chronic hypo-perfusion is typically due
atherosclerosis
may be due to vasculities
WHILE ACUTE occlusions are due to emboli
Incidence of PAD increase with
age exceeding by 70 percent by age 75
Patients with PAD have 3-5 increased risk of
MI and CVA
S/S PAD
intermittent claudication
Resting extremity pain
Decreased pulses
Subcutaneous atrophy
Hair loss
Coolness
Cyanosis
- Relief with hanging LE extremity over bed
PAD risk factors
Advanced Age
Family hx
Smoking
DM
HTN
Obesity
Cholesterol increase
What do people with PAD have relief with hanging their lower extremities over the side of their bed
due to increased hydrostatic pressure
PAD Diagnosis
Doppler US - provide pulse waveform to identify arterial stenosis
Duplex US–> plaque formation and calcification
Trancutaneus Oximetry - assess ischemia
MRI with contrast angiography - to guide endovascular intervention or surgical bypass
PAD medical treatment
Exercise
Bp control
Cholesterol control
Glucose control
PAD medical intervention
Revascularization indicated w/ disabiling claudication or ischemia
Surgical reconstruction - arterial bypass procedure
Endovascular repair - transluminal angioplasty or stent placement
Acute Artery Occulsion is frequently due to
cardiogenic emboli
Common causes of Acute Artery Occlusion
Left artial thrombus arising from Afib
Left ventricular thrombus from dilated cardiomyopathy after MI
Acute Artery Occlusion Less common causes
valvular heart dz, endocardidits , PFO
Noncardiac: atheroemboli, plaque rupture, hypercoagulability, trauma
S.S of acute artery occlusion/acute limb ischemia
Limb ischemia, pain/parethesia, weakness, decrease peripheral pulses, cool skin, color changes distal to occulusion
Acute Artery Oclussion Diagnosis
Arteriography
Treatment for Acute Artery Occlusion
surgical embolectomy, anticoagulation, amputation ( last resort)
Subclavian Steal Syndrome
SCA ( superior cerebellar artery) proximal to vertebral artery
– causing vertebral artery blood flow to be diverted away from brainstem
Subclavian Steal Syndrome ss
Syncope
Vertigo
Ataxia
Hemiplegia
**ipsilateral arm ischemia
**effected arm SBP may be 20 mmhg lower
Bruit over SCA *superior cerebellary artery
Risk Factors for Subclavian Steal Syndrome
Atheroscelorisis
Takayasu Arteritis
aortic surgery
Subclavian Steal Syndrome Rx
SC endarterectomy is curative
Raynaud’s Phenomenom
Episodic vasospastic ischemia of the digits
effects more woman
Raynauds S/S
CREST syndrome
digital blanching or cyanosis with cold exposure or SNS activation
Raynauds Phenomenom treatment
protection from cold
CBB
Alpha channel bloclers
**surgical sympathectomy for severe ischemia
Peripheral Venous Disease
What are the most common PVD process that occur during surgery?
superficial thrombophelibitis
deep vein thrombosis
chronic venous insufficiency
Why is DVT a major concern
can lead to PE leading to increase MM
What is Virshows Triad as it relates to Peripheral Venous Disease
hypercoagulability
venous stasis
*disrupted vascular endothelium
Risk factors for thromboembolism
pregnancy
low cardiac output - chf
varicose veins
estrogen - oral contraceptives
Obesity
Inflammatory disease
Superficial Thrombophlebitis & DVT is highest in what type of surgeries?
appox 50% total hip replacements
DVT diagnostics
doppler U/S more sensitive for detecting PROXIMAL thrombosis over distal thrombosis
Venography and impedance plethysmography also useful
DVT associated with these risk factors
↑risk factors: >age 40, surgery >1h, cancer, ortho surgeries on pelvis & LEs, abdominal surgery
Prophylaxis for –> Superficial Thrombophlebitis & DVT
SCDs
SBQ heparin 2-3 days
What type of anesthesia can decrease risk of superficial thrombophlebitits and DVT
Regional anesthesia can greatly ↓risk d/t earlier postop ambulation
Risk and Predisposing Factors For Development of DVT
age greater than 40
knee or hip replacement ( high risk)
stroke
pregnancy ( low and med risk)
Mod Risk Steps to Prevent DVT
subq heparin
iv dextran
compression
High Risk DVT ways to prevent
compression
subq heparin
**warfarin
iv dextran or VENA CAVA FILTER
Repeat on day _ and _
compression ultrasound of proximal veins or impedence plethysmography
2 and 7
DVT treatments Anticoags
Warfarin + Heparin
or
LMWH
DVT treatmemnt
LMWH advantages over unfractionated heparin
longer half life(?) and more predicatable dose response
Doesnt require serial assessment of APPT
Less bleeding
DVT treatment
LMWH disadvantages
higher cost
lack of reversal agent
DVT Treatment
Warfarin (vit K antagonist) is initiated during heparin treatment and adjusted to achieve INR btw ____
2-3
DVT treatment
When is heparin discontinued
in terms with warfarin
heparin discontined when warfarin achieves therapeutic effect
DVT treatment
PO anticoagulants continued _____
6 months or longer
_____ may be placed in pts w/ recurrent PE, or have contraindication to anticoagulants
IVC Filter
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
Large-artery vasculitis
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
Systemic Vasculities
Additionally,vasculitis can be a feature of connective tissue diseases such as
systemic lupus erythematosus and rheumatoid arthritis
Temporal (Giant Cell) Arteritis
Is what?
Inflammation of arteries of the head and neck
Temporal (Giant Cell) Arteritis
S/S
unilateral, headache, scalp tenderness, jaw claudication
Temporal (Giant Cell) Arteritis
Opthalmic Arterial branches may lead to ___________
ischemic optic neuritis and unilateral blindness
Temporal (Giant Cell) Arteritis Treatment
Prompt initiation of corticosteroids indicated for visual symptoms, to prevent blindness
Temporal Giant Cell Arterities
Diagnostics
Biopsy of temporal artery shows arteritis in 90% of pts
Aortic aneurysm: Dilation of all ___ layers of artery, leading to a >___increase in diameter
3
50 percent
When is surgery indicated for aortic aneursym
Surgery indicated @ >5.5 cm diameter
Aortic aneurysmrupture is associated with a 75% mortality rate
2 Types -Aortic Aneurysm
2 types:
Fusiform: Uniform dilation along entire circumference of arterial wall
Saccular: berry-shaped bulge to one side
Whats the fastest way to diagnose a suspected dissection
*In suspected dissection, doppler echocardiogram is fastest/safest measure of obtaining adiagnosis ofaneurysm
Thromboangiitis Obliterans “Buerger Disease”
Patho
Inflammatory vasculitis leading to small & medium vessel occlusions in the extremities
What triggers Thromboangiitis Obliterans “ Buerger Disease”
autoimmune response trigged by nicotine
TOBACCO USE is the most predisposing factor
Buerguer Disease more often in what gender
males less than 45
5 diagnostic criteria for Thromboangiitis Obliterans
- history of smoking
2.onset before 50
3.infrapopliteal arterial occlusive
4.upper lumb involvement
5.absense of risk factors for atherosclerosis *outside of tobacco
Buerger Disease Diagnosis is confirmed with
Biopsy of vascular lesions
Thromboangiitis Obliterans “Buerger Disease” SS
forearm, calf, foot claudication
Ischemia of hands and feet
ulceration and skin necrosis
Raynaud’s is commonly seen
Thromboangiitis Obliterans “Buerger Disease” Treatment
Smoking Cessation ** is most effective
Surgical revascularization
No effective pharmacologic tx
Anesthesia implications for Thromboangiitis “Beurger Disease”
Meticulous Positioning/Padding
Avoid cold; warm the room and use warming devices
**PREFER NON invasive BP versus conservative line placement
Polyarteritis Nodosa patho
Antineutrophyl cytoplasmic antibody (ANCA) negative vasculitis
Small & medium arteries involved
Polyarteritis Nodosa is associated with
Hep B, Hep C, or hairy cell leukemia
Polyarteritis Nodosa
Inflammation results in
glomerulonephritis, myocardial ischemia, peripheral neuropathy and seizures
What is the primary cause of death for polyarteritis nodosa?
renal failure
**htn in this disease is generally caused by this disease
Polyarteritis Nodosa RX
Tx: steroids, cyclophosphamide, treating underlying cause (s/a cancer)
Polyarteritis Nodosa Anesthesia Complications
Consider coexisting renal dz,cardiac dz and htn
**STEROIDS BENEFICIAL
Lower Extremity Chronic Venous Disease is due to
Long standing venous reflux & dilation
Effects 50% of the population
Lower Extremity Chronic Venous Diseasess
Ranges mild-severe
Mild sx: telangiectasias, varicose veins
Severe sx: edema, skin changes, ulceration
Lower Extremity Chronic Venous Disease Risk Factors
advanced age
family hx
pregnancy
ligamentous laicity
previous venous thrombosis
LE injuries
prolonged standing
obesity
smoking
sedentary lifestyle
high estrogen levels
Lower Extremity Chronic Venous Insufficiency Diagnosis
Diagnostic criteria: Sx of leg pain, heaviness, fatigue
Confirmed by ultrasound showing venous reflux
Retrograde blood flow > 0.5 seconds
Lower Extremity Chronic Venous Insufficiency treatment
Treatment: initially conservative
Leg elevation
Exercise
Weight loss
Compression therapy
Skin barriers/emollients
Steroids
Wound management
Lower Extremity Chronic Venous DiseaseConservative medical management:
Conservative medical management:
Diuretics
Aspirin
Antibiotics
Prostacyclin analogues
Zinc sulphate
*If management fails, ablation may be performed
Ablation for Chronic Venous Dz
Indications
Venous hemorrhage
Thrombophlebitis
Symptomatic venous reflux
methods chronic venous insufficiency
Thermal ablation w/laser
Radiofrequency ablation
Endovenous laser ablation
Sclerotherapy
Contraindications for Ablation for Chronic Venous
Pregnancy
Thrombosis
PAD
Limited mobility
Congenital venous abnormalities
Lower Extremity Chronic Venous
Surgical Intervention
Procedures
Saphenous vein inversion
High saphenous ligation
Ambulatory Phlebectomy
Transilluminated-powered phlebectomy
Venous ligation
Perforator ligation
___________are the leading cause of perioperative morbidity and mortality in patients undergoing noncardiac surgery
Cardiac complications
The incidence of these complications is higher in patients undergoing vascular surgery
_______ is a systemic disease. Pts with peripheral arterial dz have a 3-5 times greater risk of cardiovascular ischemic events
Atherosclerosis
Data from ______________ and _________ studies suggest thatcarotid artery stenosis with a residual luminal diameter of 1.5 mm (70–75% stenosis)represents significant stenosis. If collateral cerebral blood flow is notadequate, TIAs and ischemic infarction can occur
transcranial doppler and carotid duplex ultrasound
_____________ may be observed frequently during and after carotid endarterectomy
- Both hypertension and hypotension
__________ is typically caused by cardiogenic embolism. Emboli may arise from a thrombus in the left ventricle that develops because of MI or dilated cardiomyopathy
Acute arterial occlusion
Other cardiac causes of systemic emboli are _________
valvular heart disease, prosthetic heart valves, infective endocarditis, left atrial myxoma, Afib, and atheroemboli
- __________is an inflammatory vasculitis leading to occlusion of small and medium-sized arteries and veins in the extremities
Thromboangiitis obliterans
Pts at low risk for DVT require minimal prophylactic measures such as
early postop ambulation and compression stockings
The risk of DVT may be much ______ in patients >40 y/o who are undergoing surgery >1 hour, especially LE orthopedic, pelvic or abdominal surgery, and surgeries that require a prolonged bed rest or limited mobility
higher
Endovascular repair of aortic lesions is a relatively new technique with significant improvements in perioperative mortality
t/f
Aortic Dissection patho
Dissection: Tear in intimal layer of the vessel, causingblood to enter the medial layer
__________procedures have emerged as alternative, less invasive methods of arterial repair
Endovascular arterial
Ascending dissection: Catastrophic, requiresemergent surgical intervention
Stanford A, Debakey 1 & 2
Mortality increases by 1-2% per hr
Overall mortality 27-58%
Aortic Dissection S/S
Sx: Severe sharp pain in posterior chest or back
Aortic Dissection
Stable Versus Unstable Diagnosis
Diagnosis:
Stable= CT, CXR, MRI, Angiogram
Unstable=Echocardiogram
Stanford A Dissection
Ascending aorta: All patients with acute dissection involving the ascending aorta should be considered candidates for surgery
The most commonly performed procedures:
ascending aorta & aortic valve replacement w/a composite graft
replacement of the ascending aorta and resuspension of the aortic valve
Stanford A Dissection
Aortic Arch: in patients with acute aortic arch dissection, resection of the aortic arch isindicated. Surgery requires cardiopulmonary bypass, profound hypothermia, and aperiod of circulatoryarrest
With current techniques, a period of circulatory arrest of 30-40 minutes at a bodytemperature of 15-18°C can be tolerated by mostpatients
Neurologic deficits are the major complications associated with replacement of theaorticarch
These occur in 3-18% of pts, and it appears that selective antegrade cerebral perfusiondecreases but does notcompletely eliminatethe morbidity and mortality associated with thisprocedure.
Stanford B Dissection
Descending thoracic Aorta: Pts with an acute, but uncomplicated type B aortic dissection who have normal hemodynamics, no periaortic hematoma, and no branch vessel involvement can be treated with medical therapy
Medical therapy consists of:
1) intraarterial monitoring of SBP and UOP
2) drugs to control BP and the force of LV contraction (BBs, Cardene, SNP)
This patient population has an in-hospital mortality rate of 10%
The long-term survival rate with medical therapy only is 60-80% at 5 years and 40-50% at 10 years
Surgery is indicated for patients with type B aortic dissection who have signs of impending rupture (persistent pain, hypotension, left-sided hemothorax); ischemia of the legs, abdominal viscera, spinal cord, and/or renal failure
Surgical treatment of distal aortic dissection is associated with a 29% in-hospital mortality rate
_____ arch dissections- emergent surgery
Ascending
Descending arch dissections- rarely treated with urgent surgery
Uncomplicated type B → often admitted for BP control (SA BBs preferred, Aline)
Impending rupture of type b dissection
Sx of impending rupture (posterior pain, HoTN, hemothorax)→surgical tx
Aortic Dissection Risk Factore
Risk Factors: HTN, atherosclerosis, aneurysms, fam hx, cocaine use, & inflammatory diseases
Aortic Dissection Inherited Disorders
Marfans, Ehlers Danlos, Bicuspid Aortic Valve, non-syndrome familial hx
Causes of Dissection
Causes of dissection: blunt trauma, cocaine, iatrogenic (c/b medical treatment)
Dissection - Iatrogenic causes
Iatrogenic causes related to: cardiac catheterization, aortic manipulation, cross-clamping & arterial incision
Dissection is more common in
in men and pregnant women in 3rd trimester
