Vascular Disease (Exam III) Flashcards
What are some coexisting diseases that are commonly seen in vascular surgery patients? Which 3 are the MOST common?
- CAD - 40-80% of vasc patient have this
- HTN- (most common)
- Diabetes- (most common)
- Smokers- (most common)
- CNS atherosclerosis
- Renal
Good to know - From Brooke
What are the 3 main arterial Pathologies?
aneurysms, dissections, occlusions
- Aorta and its branches are more likely to be affected by aneurysms and dissections
- Peripheral arteries are more likely to be affected by occlusions
slide 3
2 types of aortic aneurysms
- fusiform: uniform dialation along the entire corcumference of the arterial wall
- saccular: berry-shaped bulge to one side
slide 4
Signs and symptomes of aortic aneurysms, and diagnostic tools
- s/s: can be asymptomatic or can have pain due to surrounding compression
- diagnostic tools: CT, MRI, CXR, angiogram, echo (in a suspected dissection, a doppler echocardiogram is the fastest and safest measure to diagnose)
slide 4
Treatment of aortic aneurysms
- Medical management to ↓expansion rate
- Manage BP, Cholesterol, stop smoking
- Avoid strenuous exercise, stimulants, stress
- Regular monitoring for progression
- Surgery indicated if >5.5 cm, growth >10mm/yr, or a family history of dissection
- Endovascular stent repair has become a mainstay over open surgery w/graft
slide 5
What are the risk factors for vascular disease?
- Diabetes mellitus
- Dyslipidemia
- Family history
- Hypertension
- Obesity
- Older age: 75 y/o and up
- Smoking (2x)
In a patient with vascular disease what other issues should we be sure to evaluate in preop? Why does it matter?
- CAD
- pulm dysfunction
- renal dysfunction
- neuro dysfunction
- endocrine dysfunction
- Matters d/t disease process not being limited to arterial beds in periphery → its everywhere
from Brooke, good to know
What is the primary goal for invasive monitoring of a vascular surg patient?
To detect cardiac problems; a-line might be necessary
from Brooke
Peripheral Venous Disease (common processes that occur during surgery)
- Superficial thrombophlebitis
- Chronic venous insufficiency
- DVT- major concern bc it can lead to PE, a leading cause of perioperative M & M
- Virchows Triad: 3 major factors that predispose to venous thrombosis
Venous stasis
Hypercoagulability
Disrupted vascular endothelium
Sldie 30
Superficial Thrombophlebitis and DVT are common in surgery.
Occur in approximately _ total hip replacements
Normally _ and usually _
* Risk factors for DVT:
- 50%
- subclinical and usually completely resolve
- Risk factors: >age 40, surgery >1h, cancer, ortho surgeries on pelvis & LEs, abdominal surgery
slide 31
Diagnostics and Prophylactic measures for SVT and DVT
- Diagnostics: Doppler U/S sensitive for detecting proximal thrombosis > distal thrombosis, Venography and impedance plethysmography are also useful diagnostic tools
-
Prophylactic measures: SCD’s, SQ heparin 2-3x/day
Regional anesthesia can greatly ↓risk d/t earlier postop ambulation
slide 31
DVT treatment
- Anticoagulation: Warfarin + Heparin or LMWH
- Warfarin (vit K antagonist) is initiated during heparin treatment and adjusted to achieve INR btw 2-3
- Heparin discontinued when Warfarin achieves therapeutic effect
- PO anticoagulants continued 6 months or longer
An IVC filter may be placed in pts w/ recurrent PE, or have contraindication to anticoagulants
slide 34
LMWH advantages and disadvantages
-
Advantages: longer HL & more predictable dose response,
doesn’t require serial assessment of activated partial thromboplastin time, Less risk of bleeding - Disadvantages: Higher cost, Lack of reversal agent
slide 34
What causes intermittent claudication?
- When O₂ demand exceeds supply
from Brooke
When might revascularization for PVD be considered?
- Disabling claudication
- Ischemic rest pain
- Impending limb loss
from Brooke
What are risk factors for stroke?
- Age;
- Atrial fibrillation;
- Black race;
- History/family history;
- HTN/smoking/diabetes;
- Hypercholesterolemia;
- Male;
- Obesity;
- Sickle cell disease
from brooke
What are some ways we might diagnose a stroke?
- Angiography;
- Carotid bruit with auscultation
- Carotid stenosis;
- Sudden neurological deficits
slide 18 and 19
Where does carotid stenosis most often occur? and what should our workup include?
Carotid bifurcation
due to turbulent blood flow at the branch point
* Workup includes: evaluation for sources of emboli (AFib), heart failure, valvular vegitation, or paradoxical emboli
slide 19
Treatment of CVA
- AHA recommends TPA withing 4-5Hours
- IR
- Carotid Endarterectomy (CEA) - lumen diameter 1.5mm or >70% blockage
- Carotid stenting (alternative to CEA) major risk for microembolization
- Ongoing medical treatment: antiplatelet agents, smoking cessation, BP control, cholesterol control, diet and physical activity
slide 20
CEA preop evaluation
- Neuro eval
- CV disease (CAD is prevalent, MI is a major cause of complications in the OR_)
- HTN is common - establish an acceptable BP range
- CPP=MAP-ICP
- Maintain collateral flow through stenotic vessels
- extreme head rotation may compress blood flow
- cerebral oximetry divices to determine perfusion
slide 21
Cerebral oximetry - real time data
Effected by: MAP, CO,SaO2, HGB, PaCO2
cerebral O2 consumption effected by: temp and anesthesia
slide 22
Peripheral artery disease
Compromised blood flow to the extremities
* defined by ankle-brachial index (ABI) <0.9
* ratio = SBP at ankle: SBP at brachilal artery
* chronic hypoperfusion due to atherosclerosis or vasculitis
slide 23
PAD acute occlusions are typically due to _
Incidence of PAD increases with _, exceeding 70% by _
Atherosclerosis is _, a pt with PAD has _ increased risk of _ and _
- embolism
- age 70
- systemic, 3-5x, MI and CVA
slide 23
Peripheral Artery disease Risk factors
- advanced age
- family history
- smoking
- DM
- HTN
- obersity
- increased cholesterol
slide 24
Peripheral artery disease signs and symptoms
- intermittent claudication
- resting extremity pain
- decreased pulses
- subcutaneius atrophy
- hair loss
- coolness
- cyanosis
- relief with hanging lower extremity over the side of the bed to increase hydrostatic pressure
slide 24
Diagnosis and treatment of PAD
Diagnosis: Doppler US, Duplex US (can ID areas of plaque formation), transcutansius oximetry, MRI with contrast to guide intervention or sugical bypass
Treatement: exercise, BP cholesterol and glucose control, revascularization is indicated with disabling claudication
* surgical reconstruction - bypass
* endovascular repair - transluminal angioplasty or stent placement
slide 25
Acute artery occlusion (due to what? and causes)
frequently d/t cardiogenic embolism
* common causes: Left atrial thrombus arising from Afib, Left ventricular thrombus arising from dilated cardiomyopathy after MI
* Less common causes: valvular heart dz, endocarditis, PFO, atheroemboli, plaque rupture, hypercoagulability, trauma
slide 26
Acute artery occlusion (s/s, diagnosis and treatment)
- s/s: limb ischemia, pain/paresthesia, weakness, ↓peripheral pulses, cool skin, color changes distal to occlusion
- Diagnosis: Arteriography
- Treatment: Surgical embolectomy, anticoagulation, amputation (last resort)
slide 26
Subclavian Steal Syndrome (definition, s/s)
- occluded SCA, proximal to vertebral artery causing vertebral artery blood flow to be diverted away from brainstem
- s/s: Syncope, vertigo, ataxia, hemiplegia, ipsilateral arm ischemia
Effected arm SBP may be ̴20mmhg lower
Bruit over subclavian artery
slide 27
Subclavian steal syndrome (risk factors and treatment)
Risk factors: Atherosclerosis, Takayasu Arteritis, aortic surgery
Treatment: stents or sx (its curative)
slide 27
Raynaud’s Phenomenon (definition, s/s)
Episodic vasospastic ischemia of the digits
Effects women > men
May appear with CREST syndrome (scleroderma subtype)
* S/S: digital blanching or cyanosis w/cold exposure or SNS activation
slide 29
Raynaud’s Phenomenon (diagnosis and treamtent)
- Diagnosis: based on history and physical
- Treamtent: protection from cold, CCB’s, alpha blockers, Surgical sympathectomy for severe ischemia
slide 29
Carotid disease diagnostic testing
- angiography
- CT/MRI
- Transcranial doppler US: may give indirect evidence of vascular occlusions
- carotid auscultation
- carotid US
slide 19
Systemic Vasculitis (definition)
- 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
slide 35
Systemic Vasculitis (size of artery inclusions)
- Large artery vasculitis: Takayasu arteritis, Temporal (or giant cell) arteritis
- Medium Artery: Kawasaki disease (most often in the coronary arteries)
- medium/small artery: thromboangiitis obliterans, Wegener granulomatosis, polyarteritis nodosa
Additionally, vasculitis can be a feature of connective tissue diseases such as systemic lupus erythematosus and rheumatoid arthritis
slide 35
Temporal (Giant Cell) Arteritis (Definition, s/s)
Inflammation of arteries of the head and neck
* S/S: unilateral; headache, scalp tenderness, jaw claudication
Opthalmic Arterial branches may lead to ischemic optic neuritis and unilateral blindness
slide 36
Temporal (Giant Cell) Arteritis (Treatment and Diagnostics)
- Treatment: Prompt initiation of corticosteroids indicated for visual symptoms, to prevent blindness
- Diagnosis: Biopsy of temporal artery shows arteritis in 90% of pts
Slide 36
Thromboangiitis Obliterans “Buerger Disease” (Definition and predisposing factors)
- Inflammatory vasculitis leading to small & medium vessel occlusions in the extremities (Autoimmune response triggered by nicotine)
- Tobacco use is most predisposing factor, Most prevalent in men <45
Slide 37
Thromboangiitis Obliterans “Buerger Disease” (5 diagnostic criteria)
5 diagnostic criteria:
* h/o smoking
* onset before 50
* infrapopliteal arterial occlusive dz
* upper limb involvement
* Absence of risks factors for atherosclerosis (outside of tobacco)
Diagnosis confirmed w/biopsy of vascular lesions
Slide 37
Thromboangiitis Obliterans “Buerger Disease” S/S
- forearm, calf, foot claudication
- Ischemia of hands & feet
- Ulceration and skin necrosis
- Raynaud’s is commonly seen
Slide 38
Thromboangiitis Obliterans “Buerger Disease” Treatment and Anesthesia implications
- Treatment: Smoking cessation-most effective tx, Surgical revascularization
No effective pharmacological tx - Anesthesia Implications: Meticulous positioning/padding, Avoid cold; Warm the room and use warming devices, Prefer non-invasive BP and conservative line placement
Slide 38
Poluarteritis Nodosa (Definitiaon, associations, and cause of death)
- Small & medium arteries involved, Inflammation results in glomerulonephritis, myocardial ischemia, peripheral neuropathy and seizures
- May be assoc w/ Hep B, Hep C, or Hairy Cell Leukemia
- Renal failure is the primary cause of death
- HTN geerally caused by renal disease
Slide 39
_ is negative result in Polyarteritis Nodosa
Antineutrophyl cytoplasmic antibody (ANCA) negative vasculitis
slide 39
Polyarteritis Nodosa Treatments and anesthesia considerations
- Treatment: steroids, cyclophosphamide, treating underlying cause (cancer)
- Anesthesia Implications: consider coexisting renal dz, cardiac dz, and HTN, Steroids likely beneficial
slide 39
Lower Extremity Chronic Venous Disease (Definition and s/s with ranges)
- Long standing venous reflux & dilation
- Effects 50% of the population
Ranges mild-severe - Mild sx: telangiectasias, varicose veins
- Severe sx: edema, skin changes, ulceration
Slide 40
Risk factors for Chronic Venous Disease (11)
advanced age
family hx
pregnancy
ligamentous laicity
previous venous thrombosis
LE injuries
prolonged standing
obesity
smoking
sedentary lifestyle
high estrogen levels
Slide 40
Lower extremity chronic venous insufficiency (diagnosis and treatment)
- Diagnosis: Sx of leg pain, heaviness, fatigue, Confirmed by ultrasound showing venous reflux, Retrograde blood flow > 0.5 seconds
- Treatment: initially conservative
Leg elevation
Exercise
Weight loss
Compression therapy
Skin barriers/emollients
Steroids
Wound management
Slide 41
Lower Extremity Chronic Venous Disease Medical management
Diuretics
Aspirin
Antibiotics
Prostacyclin analogues
Zinc sulphate
*If management fails, ablation may be performed
slide 42
Ablation for chronic venous disease (methods, indication, contraindications)
- Methods: Thermal ablation w/laser, Radiofrequency, ablation, Endovenous laser ablation, Sclerotherapy
- Indications: Venous hemorrhage, Thrombophlebitis, Symptomatic venous reflux
- Contraindications: Pregnancy, Thrombosis, PAD, Limited mobility, Congenital venous abnormalities
slide 43
Surgical Intervention for Lower Extremity Chronic Venous disease
Surgical intervention-usually last resort
Procedures:
Saphenous vein inversion
High saphenous ligation
Ambulatory Phlebectomy
Transilluminated-powered phlebectomy
Venous ligation
Perforator ligation
slide 44
What are two sources of possible major complications for anesthesia during aorta repair surgery?
- Aortic cross-clamping
- Intraoperative blood loss
from Brooke
Ascending Aortic Dissection
Catastrophic - requires emergent surgical intervention
* Stanford A, or Debakey 1&2, mortality increases 1-2% per hour
* overall mortality: 27-58%
slide 6
How are aortic dissections classified?
- DeBakey I II III;
- –OR–;
- Stanford A (proximal) or B (Distal)
Describe each of the DeBakey classifications?
- DeBakey I → Dissection in the ascending aorta that extends into the descending aorta;
- DeBakey II → Dissection in the ascending aorta that does notextend into the descending aorta;
- Debakey III → Dissection in the descending aorta distal to left subclavian;
- Debakey IIIA → extension to abdominal aorta;
- Debakey IIIB → doesn’t extend to abdominal aorta
What is an aortic dissection?
- Characterized by a spontaneous tear of the vessel wall intima permitting the passage of blood along false lumen - this causes blood to enter the medial layer
slide 6
What is the most common factor contributing to the progression of an aortic dissection? Most serious complication is?
- Common factor = HTN;
- Complication = aneurysm rupture
from Brooke
Stanford classification Type A Dissection in ascending aortia
- 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
slide 8
Stanford A Dissection of Aortic Arch
- In patients with acute aortic arch dissection, resection of the aortic arch is indicated. Surgery requires cardiopulmonary bypass, profound hypothermia, and a period of circulatory arrest
- current surgical techniques: period of circulatory arrest (30-40 min)
- body temp: 15-18 degrees C
- Neurologic defects are the major complications associated with aortic arch replacement (occur in 3-18% of pts)
slide 9
Stanford B dissection of descending thoracic aorta medical therapy
- 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
- in hospital mortaility rate of 10%
- The long-term survival rate with medical therapy only is 60-80% at 5 years and 40-50% at 10 years
- Medical therapy: intraarterial monitoring of SBP and UOP, drugs to contol BP, control contractility (beta blockers, cardene)
slide 10
Stanford B dissection surgical indications
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
slide 10
What are the 3 layers of a vessel wall?
- Tunica externa (outer);
- Tunica Media (middle);
- Tunica interna (inner)
good for us to know from Brooke
What is the normal size of the aorta in adults? When would an aortic resection be performed?
- normal = 2-3 cm in width;
- Electrive resection typ done when aneurysm is > 4 cm
from brooke
When does a pseudoaneurysm form?
- when the intima and media are ruptured andonly the adventitia or blood clotform the outer layer of the vessel
from brooke
Comparison of Aortic Aneurysm and Aortic Dissection
What are risk factors for aortic dissections? (inherited and lifestyle)
Inherited disorders:
* marfans, Ehlers Danlos, Biscuspid aortic valve
Lifestyle:
* HTN
* atherosclerosis
* aneurysms
* family history
* cocaine use
* inflammaory disorders
slide 12
What are some S/Sx of a thoracic aneurysm?
- Often asymptomatic and but exam can find:;
- Hoarseness;
- Stridor;
- Dyspnea;
- Dysphagia;
- Dilation of aortic valve annulus
from brooke
What are some S/Sx of acute aortic dissection?
- Severe sharp tearing pain;
- Hypotension/hypertension;
- Absence of peripheral pulses;
- Paraplegia/paraparesis
slide 6
How do we diagnose aneurysms/aortic dissections?
Stable: CXR, CT, MRI, Angiogram
Unstable: Echo/TEE
slide 6
What is “anterior spinal artery syndrome”? What are some adverse S/E?
- caused by lack of blood flow to the anterior spinal artery
- The anterior spinal artery is responsible to perfusing the anterior 2/3 of the spinal cord
- Ischemia leads to: loss of motor function below the infarct, diminished pain/temp/sensation below infarct, autonomic dysfuntion (HoTN and loss of bowel/bladder function)
slide 17
Anterior spinal artery syndrome is _ because the anterior spinal artery has _which makes it vunerable. What perfuses it? commmon causes?
- the most common form of spincal cord ischemia
- minimal collateral perfusion
- Perfused by: two posterior spinal arteries
- Common causes: aortic aneurysms, aortic dissection, atherosclerosis, trauma
slide 17
What famous artery perfuses the anterior spinal artery?
- Artery of Adamkiewicz or the greater radiculmedullary artery
from brooke
If you notice a patient has a pulsatile abdominal mass on exam what would you suspect?
- Abdominal aneurysm → common in people > 60 y/o
What are the classic S/Sx of an abdominal aneurysm rupture (triad)?
Hypotension, Back pain, Pulsatile mass
* most rupture to the left retroperitonrum
slide 14
Are aortic Aneurysm Ruptures always emergent surgeries?
Not always!
* Clotting or tamponade effect can prevent exanguination
* euvolemic resuscitation may be deferred until rupture is surgically controlled: without bleeding control, loss of tamponade can happen with increase of BP
* if unstable with suspected ruptured AAA - those require emergent surgery without preop testing
slide 14
Preopertive Evaluation of suspected Aortic dissestion or aneurysm (4 primary causes of mortaility)
4 primary causes: MI,
respiratory failure,
renal failure,
stoke
* Assess for CAD, valve dysfunction, heart failure
* IHD may require intervention prior to surgery
* are you able to do cardiac tests first? stress, echo etc
* severe reduction in FEV1 or renal failure may preclude a pt from AAA resection
* smoking and COPD = high predictor of respiratory failure
slide 15
What is the most important factor of post-aortic surgery renal failure? and how do we decrease it?
- preop renal dysfunction
- we try to hydrate, avoid hypovolemia, hypotension and low CO and avoid nephrotoxic drugs
slide 16
What should we do if the pt has a history of a stroke but has a AAA?
- Carotid ultrasound
- angiogram of brachiocephalic and intracranial arteries
-with severe carotid stenosis: workup for CEA (carotid endarterectomy) before elective surgery
slide 16
Surgery on the aortic arch and ascending aorta use what approach?
- Aortic arch → median sternotomy with deep hypothermic circulatory arrest;
- Ascending aortia → cardiopulm bypass
added from brooke
Cerebral Vascular Accidents (percentages,
s/s and predictor)
- 87% Ischemic and 13% hemorrhagic
- we see sudden onset neuro deficits
- Prominent predictor: carotid disease
side 18
CVA is the _ leading cause of disability in the US and the _ leading cause of death in the US.
TIA are _ ischemic strokes and resolve in _ hours
TIAs have _ greater risk of subsequent stroke
- 1st cause of disability, 3rd cause of death
- self-limiting, 24 hours
- 10x greater
slide 18
How do we calculate spinal cord perfusion pressure?
- Spinal Perf Pressure = MAP - SCP
CPP was in our lecture
What are some protective therapeutic measures we can take before the surgeon cross clamps the aorta?
- Methylprednisolone;
- Mild hypothermia;
- Mannitol (0.5g/kg);
- Renal dose dopamine (1-3 mcg/kg/min);
- Fenoldopam (0.05-0.1 mcg/kg/min);
- Maintain BP;
- Drainage of CSF
Not in our lecture, but good to know
Key points for lecture (read through)
- Cardiac complications are the leading cause of perioperative morbidity and mortality in patients undergoing noncardiac surgery
- The incidence of these complications is higher in patients undergoing vascular surgery
- Atherosclerosis is a systemic disease. Pts with peripheral arterial dz have a 3-5 times greater risk of cardiovascular ischemic events
- Data from transcranial doppler and carotid duplex ultrasound studies suggest that carotid artery stenosis with a residual luminal diameter of 1.5 mm (70–75% stenosis) represents significant stenosis. If collateral cerebral blood flow is not adequate, TIAs and ischemic infarction can occur
slide 45
Key points (read over)
- Both hypertension and hypotension may be observed frequently during and after carotid endarterectomy
- Acute arterial occlusion is typically caused by cardiogenic embolism. Emboli may arise from a thrombus in the left ventricle that develops because of MI or dilated cardiomyopathy
- Other cardiac causes of systemic emboli are valvular heart disease, prosthetic heart valves, infective endocarditis, left atrial myxoma, Afib, and atheroemboli
- Thromboangiitis obliterans is an inflammatory vasculitis leading to occlusion of small and medium-sized arteries and veins in the extremities
slide 46
Key points (read over)
- 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 higher 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
- Endovascular repair of aortic lesions is a relatively new technique with significant improvements in perioperative mortality
- Endovascular arterial procedures have emerged as alternative, less invasive methods of arterial repair
slide 47
