Endovascular Repair Flashcards
5 types of stenting procedures.
- aortic
- renal
- distal vessels
- carotids
- cerebral
What is EVAR, TEVAR, EVAAR?
- endovascular aortic repair
- Thoracic endovascular repair
- Endovascualr abdominal aortic repair
Prior to stent deployment, what is needed in the aorta?
-Landing zone of at least 1cm on both sides of graft.
What 2 things can happen with aortic branches?
- Excluded by graft
- Aortic debranching (anatomic bypass)
Why did tube grafts have a high failure rate?
-Underestimation of atheromatous disease in the illiac or distal aorta
what problem arose with Aorto-uni-iliac stent grafts, and what did it necessitate?
- Occlusion of the contralateral iliac
- fem-fem bypass
What does a modular bifurcated stent graft allow you to preserve?
Normal aorta-iliac anatomy
What is the benefit of a fenestrated stent?
-Accommodates visceral arteries
What does a branched stent graft allow for?
-Preservation vital arteries
When would a retroperitoneal approach be used?
-femoral vessels are small or heavily calcified
During a Retroperitoneal approach a conduit is sewn into what to introduce the graft?
- Distal aorta
- Proximal iliac
What two things does a hybrid procedure combine? and when is it used?
- Open surgical and endovascular stenting
- when major vessels would be occluded
Up 40% of TEVARS have lesions covering what? What does this require?
- Ostium of the left subclavian
- Pre-TEVAR carotid-subclavian bypass
Describe stage 1 of a elephant trunk repair.
- Open ascending aortc arch repair
- Leaving descending aneurysm alone
What is deep hypothermic circulatory arrest?
Find in reading
Describe stage 2 of an elephant repair.
- Endovascular repair of the descending aorta
- Connecting to previously done open ascending repair
what is Aortic Visceral Debranching ?
Clarify
When is elective repair appropriate for AAA?
-AAA > 5.0 cm or growing more the 1 cm per year
When is elective repair appropriate for TAA?
-TAA > 5.5 cm or growing more than 3 mm per year
Repair is indicated for any ________ aneurysm.
Symptomatic
Indications for EVAR over open?
- Significant co-morbidities
- Type B dissection
Name the 2 types of aortic dissection classifications?
- Debakey
- Standford
Name the 2 types of stanford dissections?
- A = Ascending or Ascending and descending
- B = Descending only
Name the 3 Debakey types?
- I = Ascending and Descending
- II = Ascending
- III = Descending
EVAR MAC considerations?
- Supine for 1-2 hours
- Deep sedation not possible for need to hold breath
- Favorable anatomy
- Favorable aneurysm (no fenestrations or branch grafts)
Central neuraxial blockade for EVAR?
- No TEE, MEP or SSEP needed
- Be careful of heparin causing hematomas
General anesthesia EVAR considerations.
-Used for: Illiac access, TEE, hemodynamic manipulations, SSEP/MEP, Difficult airway history
What are the goals for anesthesia in EVAR?
- Hemodynamic stability
- Avoid HTN and tachycardia
- Volume
- Bleeding management
Why avoid HTN and Tachycardia in EVAR?
- Decrease coronary ischemia
- Reduce wall pressure in aorta
EVAR renal considerations?
- Hypoperfusion
- graft occludes renal arteries
- Emboli of renal arteries
- Contrast induced neuropathy
How to prevent renal injuries.
- Adequate volume
- Maintain BP and CO
- Limit dye
Pharmacologic strategies for baseline kidney disease.
- Use Iso-osmolar or Non-ionic dyes
- N-Acetylcysteine
- Sodium Bicarb
- Statins
Causes of hypotension in EVAR
- Iliac artery rupture
- Accidental withdrawl leads to femoral bleed
- Rupture of aortic aneurysm
- Retroperitioneal bleed
What can build up in lower extremities? And what can it lead to?
- Lactic acid
- Lactic acidosis
________ ________ can follow EVAR of acute aortic type _____ dissection.
- Reperfusion syndrome
- B
Guide wire manipulation can what? by stimulating what?
- Arrhythmias
- Aortic baroreceptors
Over advancement of guidewire can result in what?
- Hemopericardium
- Cardiac tamponade
What 3 maneuvers are used to create a motionless field?
- Adenosine
- Rapid ventricular pacing
- Right atrial inflow occlusion
How would you treat vasospasms
Nitroglycerin into major aortic branches
Neurogenic hypotension can cause what? Leading to What?
- Acute spinal artery syndrome
- Paraplegia and neurogenic shock
Abdominal compartment syndrome may follow TEVAR for what?
-type B dissection
Why would a CSF drain be used?
-To increase spinal cord perfusion pressure and prevent spinal cord ischemia
what 2 ways can be used to increase spinal cord perfusion pressure?
- Increase MAP
- Decrease CSF pressure
What is the largest artery supplying the spine, and where does it originate?
- Artery of adamkiewicz
- from aorta @ T9-T12
Why would SSEP and MEP be utilized in EVAR?
- Ensure spinal cord perfusion
- Identify ischemic changes
When would TEE be used?
- Elephant repair
- Avoid contrast dye
- Detect endo leaks
- Aortic pathology
- ID guidewire, sheath, endograft
Occlusion of what 2 arteries can cause spinal cord ischemia?
- Artery of adamkiewicz
- Critical intercostal
What 4 things place one at a greater risk of spinal chord ischemia?
- Previous AAA repair
- External iliac injury
- Hypotension r/t retroperitional bleed
- Athersclerosis of thoracic aorta
How do you treat parapelgia?
- Increase MAP
- CSF drainage
- Repeated neuro exams
- Avoid abrupt cessation of CSF drain
What is the goal during graft deployment? What should be used?
- Reduce blood flow through aorta.
- Esmolol, nipride, clevidpine
Why is a motionless field so important after graft deployment?
- Landing zones close to vessels
- Windsock effect
