Vascular Disease (4) Flashcards
What are the 3 main arterial pathologies?
- aneurysm
- dissections
- occlusions
______ is more likely to be affected by aneurysm and dissections
Aorta and its branches
What is the definition of aortic aneurysm?
Dilation of all 3 layers of artery, leading to >50% increase in diameter
What are S/S of aortic aneurysm?
D/t compression of surrounding structures
- Asymptomatic or pain
When is surgery indicated for an aortic aneurysm?
> 5.5 cm diameter
growth >10mm/yr, family h/o dissection
Aortic aneurysm rupture is associated with ____% mortality rate
75
What are the 2 types of aortic aneurysms?
- Saccular: outpouching bulge to one side
- Fusiform: Uniform circumferential dilation
What are diagnostic tools for aortic aneurysms?
CT, MRI, CXR, Angiogram, echocardiogram
In suspected dissection what is the fastest and safest measure of obtaining a diagnosis of aortic aneurysm?
Doppler echocardiogram
What are treatment options for aortic aneurysms?
- Medical management to ↓expansion rate
- Manage BP, Cholesterol, stop smoking
- Avoid strenuous exercise, stimulants, stress
- Regular monitoring for progression
_________ _________ ________ has become a mainstay over open surgery w/graft
Endovascular stent repair
CV surgeon on standby incase of rupture
What is an aortic dissection?
Tear in intimal layer of the vessel, causingblood to enter the medial layer
What type of dissection requires emergent surgical intervention?
Ascending dissection
What is the overall mortality of ascending aortic dissection? How is mortality affected with each hr that passes?
Overall mortality: 27-58%
Mortality increases by 1-2%/hr
What are S/S of aortic dissection?
Severe sharp pain in posterior chest or back
How is aortic dissection diagnosed (Stable vs unstable)?
Stable: CXR, CT, MRI, Angio
Unstable: Echo
What are the DeBakey classifications for aortic aneurysms/dissection?
DeBakey I: Tear in ascending aorta that propagates to the arch
DeBakey II: Tear confined to the ascending aorta
DeBakey III: Tear in descending aorta
What are the Stanford classifications for aortic aneurysms/dissection?
Stanford A: Tear in ascending aorta
Stanford B: Tear in descending aorta
What are the most commonly performed procedures for Stanford A dissections?
- Ascending aorta & aortic valve replacement w/a composite graft
- Ascending aorta replacement with resuspension of the aortic valve
If pt has Stanford A dissection with aortic arch involvement, what is the treatment plan? What does the treatment involve?
Surgical resection
- requires cardiopulm bypass, profound hypothermia and a period of circulatory arrest
Circulatory arrest at a body temp of _____ to ______C for 30-40 minutes can be tolerated by most pts that have surgical resection of aortic arch
15-18
_______________ deficit is a major complications associated with aortic arch replacement
Neurologic (seen in 3-18% of pts)
How is an uncomplicated Stanford B dissection treated?
Medical treatment if
- normal hemodynamics
- no hematoma
- no branch vessel involvement
What does medical therapy consist of for Stanford B dissections?
- Intraarterial monitoring of SBP and UOP
- Drugs to control BP and the force of LV contraction (BBs, Cardene, nipride)
What is the in hospital mortality rate of Stanford B dissections? What is the long term survival rate with medical Tx?
Mortality: 10%
Long term survival rate: 60-80% @ 5yrs, 40-50% @ 10yrs
When is surgery indicated for Stanford B dissections?
Signs of impending rupture
- persistant pain
- hypotension
- left hemothorax
OR
compromised perfusion to lower body
Which aortic dissections need emergent surgery?
Ascending arch dissections
What are risk factors for aortic dissections?
- HTN
- Atherosclerosis
- Aneurysms
- Fam Hx
- Cocaine
- Inflammatory diseases
What inherited disorders increase risk for aortic dissections?
- Marfans
- Ehler Danlos
- Bicuspid aortic valve
What are common causes for aortic dissection?
- Blunk trauma
- Cocaine
- Iatrogenic (medical treatment: cardiac catheterization, aortic manipulation, cross-clamping, arterial incision)
Which group of people is aortic dissection more common in?
- Men
- Pregnancy women in 3rd tri
What is the definition of aortic dissection?
Blood entry into the media
What is the definition of aortic aneurysm?
Dilation of all 3 aortic layers
Fun little chart
What triad of symptoms are seen with aortic aneurysm rupture in 1/2 of the cases?
- Hypotension
- Back pain
- A pulsatile abdominal mass
Most abdominal aortic aneurysms rupture into the ______ _______________
Left retroperitoneum
What would prevent hypovolemic shock with a ruptures aortic aneurysm?
Clotting and tamponade in retroperitoneum preventing exsanguination
If retroperitoneal tamponade occurs, volume resuscitation may be delayed until the rupture is surgically controlled. Why?
To maintain a lower BP and reduce risk of further bleeding, hypotension, and death
What are 4 primary causes of mortality r/t surgeries of thoracic aorta?
- MI
- Respiratory failure
- Renal failure
- Stroke
What is important in preop assessment before thoracic aorta surgery?
Assess for presence of:
- CAD
- Valve dysfunction
- Heart failure
What may preclude a pt from aortic resection?
- Low FEV1
- Renal failure
What are predictors of post aortic surgery respiratory failure?
- Smoking
- COPD
Consider bronchodilators, ABX, CPT
What is the most significant indicator of post-aortic surgery renal failure?
Preop renal dysfunction
What are steps to prevent post-op aortic surgery renal failure?
Preop hydration
Avoid:
- hypovolemia
- hypotension
- low CO
- nephrotoxic drugs
If a patient has a history of stroke, what should be evaluated in preop before aortic surgery?
- Carotid ultrasound
- Angio of brachiocephalic and intracranial arteries
- Severe aortic stenosis→ work up for CEA before elective surgery
What causes anterior spinal artery syndrome?
Lack of blood flow to the anterior spinal artery
The anterior spinal artery perfuses the anterior _____ of the SC
2/3
What happens as a result of ischemia to the anterior spinal artery?
- Loss motor function below the infarct
- Diminished pain and temperature sensation below the infarct
- Autonomic dysfunction, leading to hypotension and bowel & bladder dysfunction
Why is Anterior spinal artery syndrome the most common form of spinal cord ischemia?
ASA has minimal collateral perfusion
Posterior spinal cord is perfused by 2 spinal arteries= better collateral circulation
What are common causes of ASA syndrome?
- Aortic aneurysms
- Aortic dissection
- Atherosclerosis
- Trauma
What is the prominent predictor of CVA?
Carotid disease
What percent of CVAs are ischemic vs hemorrhagic?
Ischemic: 87%
Hemorrhagic: 13%
What is the 1st leading cause of disability in the US and 3rd leading cause of death in US?
CVA
Risk factors of CVAs:
Sudden onset neurological deficits:
What is a TIA?
Temporary self limiting ischemia
- S/S resolve w/in 24hrs
- 10x greater risk of subsequent stroke
What diagnostics can be useful to detect carotid disease?
- Angio (diagnose occlusion)
- CT/MRI (less invasive, ID aneurysms/AVMs)
- Transcranial doppler U/S (vascular occlusion)
- Carotid auscultation (ID bruits)
- Carotid U/S (quantify degree of stenosis)
Where is a common site for carotid stenosis?
Carotid bifurcation→ d/t turbulent blood flow at the branch-point
What does workup for carotid disease include?
Evaluation for sources of emboli:
- Afib
- Heart failure
- Valvular vegetation
American heart association recommends TPA within _____hours of onset
4.5
When is IR indicated for treatment of CVA?
- Intra-arterial thrombolysis
- Intravascular thrombectomy
*benefits seen up to 8h after onset of CVA
When is carotid endarterectomy indicated?
Surgical treatment for severe carotid stenosis (lumen diameter 1.5mm or >70% blockage)
When is carotid stenting an option for CVA?
- Alternative to CEA
- Major risk of microembolization→CVA
- Embolic protection devices developed to reduce risk; so far CVA risk still unchanged
What is ongoing medical/ lifestyle treatment for CVA?
- Antiplatelet tx
- Smoking cessation
- BP control
- Cholesterol control
- Diet & Physical activity
What is involved in CEA preop evaluation?
- Neuro eval (know preop deficits)
- CV disease (MI major cause of periop mortality)
- HTN common (establish acceptable BP to optimize CPP)
- Cerebral oximetry devices (foresight/INVOS)
What is indicated if a pt has severe carotid disease and severe coronary artery disease undergoing CEA procedure?
- Must stage cardiac revascularization and CEA
- Most compromised area should take priority
What is cerebral oxygenation affected by?
- MAP
- CO
- SaO2
- Hgb
- PaCO2
What affects cerebral O2 consumption?
- Temperature
- Depth of anesthesia
What is Peripheral artery disease and what is the criteria for it?
- Compromised blood flow to extremities
- Defined by ankle brachial index (ABI) <0.9
What does the ankle brachial index measure?
Ratio of SBP at ankle compared to SBP at brachial artery
Chronic hypoperfusion from PAD is typically d/t _________.
Atherosclerosis (may also include vasculitis)
What causes acute occlusions with PAD?
Embolism
Atherosclerosis is systemic, meaning that pt with PAD have _______x increased risk of MI/CVA.
3-5x
What are risk factors of PAD?
- Advanced age
- Family Hx
- Smoking
- DM
- HTN
- Obesity
- Increased cholesterol
What are signs and symptoms of PAD?
- Intermittent claudication
- Resting extremity pain
- Weak pulses
- Subcutaneous atrophy
- Hair loss
- Coolness
- Cyanosis
*Relief with hanging lower extremity over side of bed (increases hydrostatic pressure)
How is peripheral artery disease diagnosed?
- Doppler u/s (pulse volume waveform ID stenosis)
- Duplex u/s (ID areas of plaque formation and calcification)
- Transcutaneous oximetry (severity of tissue ischemia)
- MRI w/contrast angio (guide endovascular intervention)
What are medical treatment options for PAD?
- Exercise
- Control BP
- Control cholesterol
- Control glucose
When is revascularization indicated for PAD? What procedures does this involve?
Disabling claudication or ischemia
- Surgical reconstruction- arterial bypass procedure
- Endovascular repair- angioplasty or stent placement
What is a common cause of acute peripheral artery occulsion?
Cardiogenic embolism
common causes→ Left atrial thrombus from afib, left ventricle thrombus from cardiomyopathy after MI
What are S/S of acute peripheral artery occlusion?
- Limb ischemia
- Pain/parasthesia
- Weakness
- ↓ peripheral pulses
- Cool skin
- Color changes distal to occlusion
How is an acute peripheral artery occlusion diagnosed? What is the treatment?
Arteriogram
Tx: : anticoagulation, surgical embolectomy, amputation (last resort)
What is subclavian steal syndrome?
Occluded SCA, proximal to vertebral artery
Vertebral artery flow diverts away from brainstem
What are S/S of Subclavian Steal Syndrome?
- Syncope
- Vertigo
- Ataxia
- Hemiplegia
- Ipsilateral arm ischemia
- Effected arm BP may be 20mmHg lower
- Bruit over SCAW
What are risk factors for subclavian steal syndrome?
- Atherosclerosis
- Hx aortic surgery
- Takayasu arteritis
Treatment for Subclavian steal syndrome:
SC endarterectomy
What is Raynauds phenomenon? Which gender is predominately effected?
Episodic vasospastic ischemia of the digits
- More common in women
What are primary and secondary causes of raynauds phenomenon? (I dont think she really cares about these but just incase)
What are S/S of raynauds phenomenon?
Digital blanching/cyanosis with cold exposure or SNS activation
How is raynauds diagnosed? What is the treatment?
Based on history and physical
Tx: protection from cold, CCBs, Alpha blockers, surgical sympathectomy for severe ischemia
What are common peripheral venous disease processes that occur during surgery?
- Superficial thrombophlebitis
- Deep vein thrombosis
- Chronic venous insufficiency
What is a major concern associated with PVD and why?
DVT→ can lead to PE→ leading cause of perioperative mortality
What is virchows triad and what disease process is associated with it?
3 factors that predispose to VENOUS thrombosis
- venous stasis
- disrupted vascular endothelium
- hypercoagulability
Risk factors for thromboembolism:
Superficial thrombophlebitis and DVT are common in which surgeries?
Occur in 50% of total hip replacements
(normally subclincal and completely resolves)
What are S/S associated with DVTs? What are risk factors and how is it diagnosed?
S/S: Extremity pain/swelling
Risk factors:
- >40y/o
- surgery >1hr
- cancer
- ortho surgery on pelvis/lower ex
- abd surgery
Dx: doppler u/s, venography, impedance plethysmography
What are prophylatic measures to prevent DVTs?
- SCDs
- SQ heparin 2-3 days
- regional anesthesia can greatly decrease risk (earlier postop ambulation)
What is the treatment for DVT?
Anticoagulation
- Warfarin + Heparin/LMWH
What are advantaged to LMWH over heparin in treatment of DVTs?
- Longer E1/2L
- More predictable dose response
- Doesnt require serial labs
- Less risk of bleeding
What are disadvantages of LMWH?
- higher cost
- lack of reversal
What is the goal INR when on warfarin and heparin tx for DVT? When is heparin d/c?
INR: 2-3
D/C heparin when warfarin gets to therapeutic INR
How long are PO anticoagulants continued for DVT treatment?
6 months or greater
IVC filter may be indicated for recurrent PE or if anticoagulants are contraindicated
What is systemic vasculitis?
Group of vascular inflammatory diseases categorized by the size of the vessels at the primary site of the abnormality
What does large artery vasculitis include?
- Takayasu arteritis
- Temporal (or giant cell) arteritis
What does medium artery vasculitis include?
Kawasaki disease, which usually affects the coronary arteries
What does small artery vasculitis include?
- Thromboangiitis obliterans
- Wegener granulomatosis
- Polyarteritis nodosa
What is temporal (giant cell) arteritis?
Inflammation of arteries of the head and neck
What are S/S of temporal arteritis?
- unilateral headache
- scalp tenderness
- jaw claudication
- opthalmic arterial branches may lead to ischemic optic neuritis and unilateral blindness
How is temporal arteritis diagnosed and treated?
Dx: Biopsy of temporal artery shows arteritis in 90% of pts
Tx: Corticosteroids for visual symptoms (help prevent blindness)
What is Thromboangitis Obliterans?
“Buerger disease”
- Inflammatory vasculitis leading to small & medium vessel occlusions in the extremities
- Autoimmune response triggered by nicotine
What is the most predisposing factor for Buerger disease?
Tobacco
- Most prevalent in men <45
What are the 5 diagnostic criteria for thromboangitis obliterans?
- Smoking hx
- Onset before 50
- Infrapopliteal arterial occlusive disease
- Upper limb involvement
- Absence of risk factors for atherosclerosis
How is thromboangiitis obliterans diagnosis confirmed?
Biopsy of vascular lesions
What are symptoms of thromboangiitis obliterans?
- Forearm, calf, foot claudication
- Ischemia of hands & feet
- Ulceration and skin necrosis
- Raynaud’s is commonly seen
What are treatment options for thromboangiitis obliterans?
- Smoking cessation-most effective tx
- Surgical revascularization
- No effective pharmacological tx
What are anesthesia implications for theomboangiitis obliterans?
- Meticulous positioning/padding
- Avoid cold; Warm the room and use warming devices
- Prefer non-invasive BP and conservative line placement
What is polyarteritis nodosa? What issues can it lead to?
- Vasculitis of the small and medium vessels
- Leads to glomerulonephritis, myocardial ischemia, peripheral neuropathy and seizures
-May be assoc w/ Hep B, Hep C, or Hairy Cell Leukemia
What is the primary cause of death in patient with polyarthritis nodosa?
Renal failure (HTN from renal disease)
What is the treatment for Polyarteritis Nodosa?
- Steroids
- Cyclophosphamide
- Treat underlying cause (Ex: Cancer)
What are anesthesia considerations for pts with polyarteritis nodosa?
Consider coexisiting diseases:
- renal
- cardiac
- HTN
Steroids are beneficial
What is lower extremity chronic venous disease and what percent of the population is effected?
- Long standing venous reflex and dilation
- 50% of population effected
What are the risk factors for Lower Ex Chronic venous disease?
- advanced age
- family hx
- pregnancy
- ligamentous laicity
- previous venous thrombosis
- LE injuries
- prolonged standing
- obesity
- smoking
- sedentary lifestyle
- high estrogen levels
What are the ranges of lower extremity chronic venous disease?
Mild→ Severe
- mild sx: varicose veins, telangiectasias
- severe sx: edema, skin changes, ulceration
What is the diagnostic criteria for lower extremity chronic venous insufficiency?
- Leg pain/heaviness
- Fatigue
- Confirmed by ultrasound showing venous reflux
- Retrograde blood flow > 0.5 seconds
What are the treatment options for lower extremity chronic venous insufficiency?
Start conservative
- Leg elevation
- Exercise
- Weight loss
- Compression therapy
- Skin barriers/emollients
- Steroids
- Wound management
- Diuretics
- Aspirin
- Antibiotics
- Prostacyclin analogues
- Zinc sulphate
What is the next step if conservative medical management fails for lower extremity chronic venous disease?
Surgical intervention is last resort
Procedures: ablation
- Saphenous vein inversion
- High saphenous ligation
- Ambulatory Phlebectomy
- Transilluminated-powered phlebectomy
- Venous ligation
- Perforator ligation
