Atlas of Vascular & Endovascular Surgical Techniques M Ashraf Mansour, Erica Mitchell, Murray Shames
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1Cerebrovascular
Chapter Outline
  • • Carotid Endarterectomy
  • • Aortic Arch and Four-Vessel Cerebral Angiography
  • • Carotid Angioplasty and Stent
  • • Vertebral Artery Transposition
  • • Carotid—Carotid Bypass
  • • Endovascular Therapy for Subclavian and Innominate Artery Stenosis
  • • Endovascular Treatment of Iatrogenic and Penetrating Subclavian Artery Injury
  • • Carotid Body Tumor Excision2

Carotid EndarterectomyCHAPTER 1

M AshrafMansour
 
1 PREOPERATIVE
 
1.1 Indications
  • Symptomatic carotid stenosis including amaurosis fugax, transient ischemic attack, or mild stroke.
  • Asymptomatic severe carotid stenosis. A risk—benefit analysis should be individualized for each patient, taking into account factors such as age, functional capacity, life expectancy, comorbidities, proven outcomes in the hospital, and operating surgeon.
 
1.2 Evidence
  • For symptomatic carotid stenosis ECST, NASCET, and VA trial
  • For asymptomatic carotid stenosis ACAS
  • Comparison with carotid stenting option: CREST trial
 
1.3 Instruments Needed
  • Picture of back table (Fig. 1.1)
  • Vascular instruments and clamps
  • Suture material 6.0 or 7.0 monofilament
  • Back pressure line, shunt (these include: Pruitt-Inahara, Javid, and Sundt shunts)
  • Patch (PTFE, Dacron, bovine pericardium)
  • Cw-Doppler unit or portable duplex machine for completion study (Fig. 1.2)
 
1.4 Preoperative Planning and Risk Assessment
Planning:
  • Diagnostic studies: Carotid duplex from an accredited vascular laboratory, CT angiogram, magenetic resonance angiography (MRA) or digital subtraction angiogram showing the carotid bifurcation and must include the common and internal carotid, proximal and distal to the lesion, respectively.
    zoom view
    Fig. 1.1: Picture of back table.
  • Is the patient for general or regional anesthesia?
  • Is the patient fit for surgery: Good cardiopulmonary reserve?
  • Previous operations or radiation to the neck make dissection more difficult.
  • Osteoarthritis of the cervical spine and morbid obesity make positioning the neck in surgery difficult.
  • High carotid bifurcation and high lesion (at C2 or higher) are best approached with nasotracheal intubation and temporary subluxation of the mandible.
Risk assessment:
  • Low risk: No cardiopulmonary disease, no anatomical risks, e.g. previous radiation or neck surgery, degenerative disease of the spine precluding rotation, and extension (Flowchart 1.1).
  • Intermediate risk: Low cardiac or pulmonary risk, comorbid disease such as obesity, poorly controlled hypertension and hyperlipidemia, tobacco use, and mild chronic obstructive pulmonary disease (COPD).
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    zoom view
    Fig. 1.2: CW-Doppler unit or portable duplex machine for completion study.
  • High risk: Poor ejection fraction (< 20%), angina or recent myocardial infarction (MI), oxygen-dependent COPD, previous radical neck dissection or neck radiation, tracheostomy, frozen neck (consider carotid stenting).
 
1.5 Preoperative Checklist
  • Preoperative β-blockers, statins, and aspirin should be started preoperatively.
  • There is no contraindication for maintaining Plavix preoperatively; however, there is an increased risk of bleeding.
Special considerations for diabetic patients:
Sign in
Time out
Sign out
Patient confirms:
Identity
Site
Procedure
Appropriate consent form
Team members introduction
Procedure performed
Instrument and needle final count
Labeling specimen
Equipment problems to address
Site marked
Verbal confirmation from surgeon, anesthesiologist and nurse
Anesthesia and surgeon report key concerns to PACU
Anesthesia safety checklist
Anticipated critical events
Allergy, special considerations
Antibiotic prophylaxis
Preoperative imaging
zoom view
Flowchart 1.1: Decision-making algorithm.
 
1.6 Decision-Making Algorithm
 
1.7 Pearls and Pitfalls
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zoom view
Figs. 1.3A and B: The precise location of the incision can be determined by a quick carotid duplex to show the bifurcation and mark it before prepping.
 
1.8 Surgical Anatomy
  • The best exposure to the carotid bifurcation is from the anterior approach.
  • Beware of nerves, vagus, hypoglossal, descendens hypoglossi.
  • Ligation of common facial vein to provide exposure.
  • Occasionally, ligation of a tethering vessel posterior to the hypoglossal is required for high exposure.
  • Injection of lidocaine in the bifurcation is necessary to treat bradycardia that occurs with carotid manipulation.
 
1.9 Positioning
  • I prefer a modified Fowler position, which is semisitting, with knees resting on a pillow and a small shoulder role behind the shoulders and have the neck turned to the opposite side.
zoom view
Fig. 1.4: Note hypoglossal nerve crossing the external carotid.
 
1.10 Anesthesia
  • Most surgeons and anesthesiologists prefer general endotracheal anesthesia. There are many benefits to regional cervical block, providing the patient is able to be still, the anesthesiologist able to use minimal sedation, and the surgeon confident and relaxed.
  • Supplemental local anesthesia is sometimes required after a regional cervical block, some patients experience pain with arterial manipulation.
  • If bradycardia occurs during manipulation of the carotid bifurcation during dissection, Lidocaine 1% may be injected in the bifurcation with a 25G or 27G needle, or placed topically.
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    zoom view
    Figs. 1.5A and B: Positioning.
  • A radial arterial line helps with close hemodynamic monitoring and guiding the use of pressors or antihypertensives as needed.
  • Avoiding wild fluctuation in the blood pressure is important throughout the case, but especially with induction and emergence from anesthesia.
 
2 PERIOPERATIVE
 
2.1 Incision
  • The most common type of incision is a longitudinal one, along the anterior border of the sternocleidomastoid.
  • Some surgeons prefer an oblique incision or an incision placed in a skin crease, it has a better patient acceptance. The precise location of the incision can be determined by a quick carotid duplex to show the bifurcation and mark it before prepping (See Figs. 1.3A and B).
  • The disadvantage of oblique or transverse incisions is the inability to extend caudad for common carotid exposure or cephalad for a high lesion in the internal carotid artery.
 
2.2 Steps
  • Exposure of the carotid bifurcation.
  • Avoid manipulation of the vessels because a plaque may be dislodged causing a neurological complications.
  • Clamp the distal internal carotid artery first.
  • Decision to shunt or not, based on back pressure, or if the patient is awake and can tolerate the clamp.
  • Arteriotomy on the common carotid opposite the take-off of the external carotid to allow endarterectomy and placement of a patch.
  • For eversion, I prefer an oblique incision on the common carotid artery extending to the bifurcation and complete detachment of the internal carotid artery.
  • The most important step of the procedure is to ensure an adequate removal of the distal plaque, and proper visualization of the end point. In rare cases, tacking sutures are necessary to avoid “lifting” of the distal shelf.
  • Removal of the plaque from the common and external carotid also has to be very meticulous and avoid leaving any residual loose atheroma (Fig. 1.6).
  • Copious flushing of the endarterectomy site with heparinized saline is very helpful.
 
2.3 Closure
  • The endarterectomy site is closed primarily with 6.0 or 7.0 Prolene in eversion endarterectomy.
  • A patch with Dacron, ePTFE, bovine pericardium, or vein is recommended in all other cases. Vein is preferred if infection is suspected.
  • A subcuticular closure is preferred. Most patients can be discharged on postoperative day 1 and do not need to be seen for 1–2 weeks.
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    zoom view
    Fig. 1.6: Eversion endarterectomy.
  • Some surgeons use closed suction drains, either routinely or selectively; however, there is no evidence this decreases the incidence of wound hematoma.
 
3 POSTOPERATIVE
 
3.1 Complications
  • The most serious and feared complication is stroke.
  • Stroke rate is higher for symptomatic lesions and redo operations.
  • Cranial nerve injury: Vagus, hypoglossal, marginal mandibular, rarely glossopharyngeal.
  • Wound hematoma requiring re-exploration.
  • Patch blowout: More common with vein patches.
  • Wound infection or synthetic patch infection: Quite rare in carotids.
 
3.2 Outcomes
  • The ideal stroke rate is 1–2% in centers of excellence.
  • Perioperative stroke rate is higher for symptomatic patients, and redo endarterectomy.
  • The incidence of myocardial infarction should be < 5%.
  • Patients with cardiac risk factors had a higher MI rate in the Sapphire trial.
 
3.3 Postoperative Hospitalization
  • After a period of 2–4 hours of close monitoring in a postanesthesia care unit, most patients may go to a vascular ward for neurological checks and vital signs every 4 hours.
  • Patients with blood pressure lability require monitoring in an ICU with vasopressors if hypotensive and antihypertensive drips if hypertensive.
 
3.4 Discharge Instruction
  • Patients should monitor their blood pressure postoperatively, and continue to take their medications (especially statins, antihypertensives, and antiplatelet agents).
  • We counsel patients not to drive for a week, avoid strenuous activity, and heavy lifting.
  • Wound infection is rare, but routine wound care, keeping the wound clean, and avoiding contamination is good advice.
 
3.5 Follow-Up
  • A follow-up visit in the office 2–4 weeks postoperative is recommended for wound and neuro check.
 
3.6 E-mail an Expert
 
SUGGESTED READING
  1. Hobson RW, Weiss DG, Fields WS, et al. Efficacy of carotid endarterectomy for asymptomatic carotid stenosis. N Engl J Med. 1993;328:221–7.
  1. Moore WS, Barnett HJM, Beebe HG, et al. Guidelines for carotid endarterectomy: a multi-disciplinary consensus statement form the Ad Hoc Committee, American Heart Association. Stroke. 1995;26:188–201.
  1. North American Symptomatic Carotid Endarterectomy Trial Collaborators. Beneficial effect of carotid endarterectomy in symptomatic patients with high-grade carotid stenosis. N Engl J Med. 1991;325:445–53.
  1. Walker MD, Marler JR, Goldstein M, et al. Executive Committee for the Asymptomatic Carotid Atherosclerosis Study. Endarterectomy for asymptomatic carotid artery stenosis. JAMA. 1995;273:1421–8.
  1. Warlow, C. European Carotid Surgery Trial: Interim results for symptomatic patients with severe (70–99%) or with mild (0–29%) carotid stenosis. Lancet. 1991;337:1235–43.
 
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QUIZ
Question 1: Carotid endarterectomy has been proven to be superior to best medical therapy:
  1. In the European Carotid Trial only (ECST)
  2. In the North American Trial only (NASCET)
  3. In the VA asymptomatic carotid trial only
  4. In the Asymptomatic Carotid Atherosclerosis Study only (ACAS)
  5. All the above.
Question 2: The benefit of carotid endarterectomy hinges on the track record of the surgeon performing the operation and keeping stroke rates at a minimum. The guidelines suggest that stroke rates after carotid endarterectomy should be:
  1. Less than 3% for asymptomatic patients
  2. Less than 5% for symptomatic patients
  3. Less than 10% for redo surgery
  4. A and B are correct
  5. A, B and C are correct.
Question 3: Carotid eversion endarterectomy:
  1. Cannot be performed if the patient needs an indwelling shunt
  2. Has a higher rate of restenosis compared to endarterectomy with patch closure
  3. Cannot be performed in awake patients
  4. Its main advantage is that it is faster and does not require a patch
  5. Cannot be performed if the internal carotid is redundant.
ANSWERS:
1. e
2. d
3. d