Vascular Flashcards
(123 cards)
What are the segments of the vertebral artery?
V1: origin off subclavian to foramina of C6
V2: from the foramen of C6-C2
V3: C2 foramen to dura
V4: intracranial
What structure commonly overlies the carotid bifurcation?
the facial vein
What is the first branch off the external carotid artery?
the superior thyroid artery
True or false, the external carotid can be ligated?
true
What is the first branch of the internal carotid?
the ophthalmic artery
Is the internal carotid artery flow high or low resistance?
low resistance, biphasic, no flow reversal
Are the external and internal carotid arteries triphasic or biphasic?
- external: high resistance so triphasic
- internal: low resistance so biphasic
If a patient has hoarseness after carotid endarterectomy, what structure was likely injured? How?
the vagus was likely caught in the clamp applied to the carotid
If a patient has ipsilateral tongue deviation after carotid endarterectomy, what structure was likely injured?
the hypoglossal nerve (XII), which lies just cephalic to the carotid bifurcation
If a patient has ipsilateral mouth droop after a carotid endarterectomy, what structure was likely injured? How?
the marginal mandibular branch of the facial nerve due to traction on the mandible when exposing high lesions
Which nerve lies deep to the posterior belly of the digastric? What defect is associated with injury?
- the glossopharyngeal nerve (IX)
- dysphagia
Which layers are removed during a carotid endarterectomy?
the intima and part of the media
What is the typical location of carotid atherosclerosis?
the bifurcation
What are the indications for carotid endarterectomy?
- over 50% with symptoms
- over 70% or with EDV over 100cm/s
How should a patient with symptoms of carotid stenosis < 50% be managed?
medically with DAPT, smoking cessation, and a statin
How should a patient with a stroke and 100% occlusion of the carotid be managed?
- medically with DAPT or anti-coagulation
- there is no role for recanalization and this would increase the risk of hemorrhagic conversion
In what situation would an emergent carotid endarterectomy be indicated?
crescendo TIAs
Why is cardiac clearance so important before carotid endarterectomy?
MI is the most common non-stroke cause of morbidity and mortality after CEA
When should you operate on a patient who recently had a stroke from carotid stenosis?
- within 2 weeks of symptom resolution for a TIA or small stroke
- 6-8 after a hemorrhagic stroke
What is the downside of carotid shunt during endarterectomy?
it limits visibility of the distal end point
What are four ways to monitor neurologic status and to decide whether to shunt during carotid endarterectomy?
- awake CEA
- EEG
- ICA stump pressures (>40, no shunt)
- cerebral oximetry
How does cerebral hyper perfusion syndrome present?
as headaches and hypertension but normal neurological exam following carotid endarterectomy
What is cerebral hyper-perfusion syndrome?
- a rare, potentially deadly complication of carotid endarterectomy
- usually seen in those with severe, bilateral carotid stenosis
- caused by dysfunction in cerebral vascular autoregulation
- presents as hypertension and headache post-op
- CT is used to rule out acute infarct and is likely to show cerebral edema
- treat medically with BP control, ICU monitoring, and seizure ppx
What is the best next step in a patient who appears to have stroke symptoms in PACU following carotid endarterectomy?
- duplex US
- patent ICA: to CT for distal emboli/watershed infarct
- thromboses ICA: to OR for thromboectomy