Chapter 27 - Vascular I Flashcards
What is the most common congenital hypercoagulable disorder?
Resistance activated protein C Leiden factor
What is most common acquired hypercoagulability disorder?
Smoking
What are the three stages of atherosclerosis?
1) Foam cells - macrophages that have absorbed fat and lipids in the vessel wall
2) Smooth muscle cell proliferation - caused by growth factors released from macrophages; results in wall injury
3) Intimal disruption from smooth muscle cell proliferation - leads to exposure of collagen in the vessel wall and eventual thrombus formation - fibrous plaques then form in these areas with underlying atheromas
What are the risk factors for atherosclerosis?
Smoking
hypertension
cholesterolemia
Atherosclerosis is a disease of what part of the blood vessel?
Disease of intima
Hypertension is a disease of what part of the blood Vessel?
Disease of the media
Stroke is the _____ cause of death in United States
Third
What is the most important risk factor for stroke in asymptomatic patients?
Hypertension
Where is the most common site for stenosis in the carotid arteries?
Bifurcation
The normal internal carotid artery has what type of flow?
Continuous forward flow
The normal external carotid artery has what type of flow?
Triphasic flow
Where is the communication between the internal carotid artery and the external carotid artery?
Ophthalmic artery (first branch of ICA) and internal maxillary artery off ECA
What is the most commonly diseased Intracranial artery?
Middle cerebral artery
What is the most common etiology of cerebral ischemic events?
Arterial embolization from the ICA
-Heart is the second most common source of emboli
Anterior cerebral artery events cause what?
Mental status changes, release, slowing
Middle cerebral artery events cause what?
Contralateral motor and speech loss; contralateral facial droop
What is amaurosis fugax?
Occlusion of the atomic branch of the ICA visual changes, shade coming down over eyes; visual changes are transient
-Can see Hollenhorst plaques on ophthalmologic exam
What do you do with carotid traumatic injury with major fixed deficit?
If occluded do not repair-can exacerbate injury with bleeding
If not occluded-repair
When do you consider a carotid endarterectomy?
Any pt with symptoms + >70% stenosis.
Asymptomatic pts w/ 70 to 80% stenosis controversial.
Any pt w/ >80 to 90% stenosis should have CEA if technically possible.
The patient has a recent completed stroke, when do you perform CEA?
4 to 6 weeks
When can an emergent CEA be of benefit?
When there are fluctuating neurologic symptoms or crescendo/evolving TIAs
When do you shunt during a CEA?
When the stump pressure is less than 50
What is the most common cranial nerve injury with a carotid endarterectomy?
Vagus nerve secondary to vascular clamping during endarterectomy. Patients get hoarseness
What happens with a hypoglossal nerve injury during CEA?
Tongue deviation to the side of the injury – speech and mastication difficulty
What happens with a glossopharyngeal nerve injury during a CEA?
Unlikely. Could occur with a really high carotid lesion. Causes difficulty swallowing.
What happens if you damage the Ansa cervicalis during a CEA?
Innervates strap muscles; no serious deficits
What happens if you damage the mandibular branch of the facial nerve during a CEA?
Affects corner of mouth (smile)
What do you do if there’s an acute event immediately after a CEA?
Go back to the OR to check for flap or thrombosis
How do you detect a pseudoaneurysm after a CEA and what do you do about it?
Pulsatile, bleeding mass after CEA. Draped and prepped before intubation, intubate, then repair
What percentage of patients have hypertension following a CEA and why?
20%. Caused by injury to carotid body. Treat with nipride to avoid bleeding.
What is the restenosis rate after a CEA?
15%
What are the symptoms of Vertebral artery disease and what is the treatment?
Diplopia, dysarthria, vertigo, tinnitus, drop attacks, incoordination, binocular vision loss.
-PTA, vertebral artery transposition to subclavian, transsubclavian endarterectomy, osteophyte resection, unroofing of transverse process foramina, resection of musculotendinous bands
How do carotid body tumors present?
Painless neck mass, usually at the bifurcation, made up of neural crest cells
-treat with resection
How do you get a thoracic aortic transection and what you do about it?
Deceleration injury
Address other life threatening injuries first
What are ascending aortic aneurysms usually caused by?
Usually caused by connective tissue disorder; cystic medial necrosis most common abnormality-Marfan syndrome
- Often asymptomatic and picked up on routine CXR
- Can get compression of vertebral, whore’s whisper, dyspnea, trouble swallowing
Transverse aortic arch aneurysms
From atherosclerosis. Repair symptomatic, greater than 5.5 cm, with Marfan’s greater than 5 cm