Symptomatic Patients

The differential diagnosis and detailed work-up of every patient with possible symptoms of cerebral ischemia are beyond the scope of this chapter. Flemming and colleagues provided a detailed review of the evaluation and management of TIA and minor cerebral infarction.³⁰ A patient with a history and findings on physical examination consistent with TIA or minor stroke of the anterior circulation should undergo routine laboratory evaluation (complete blood count, prothrombin time, activated partial thromboplastin time, electrolytes, fasting glucose, creatinine, erythrocyte sedimentation rate), electrocardiography, chest radiography, and computed tomography (CT) of the head without contrast enhancement. If carotid artery disease is still in the differential diagnosis, screening ultrasonography of the carotid arteries should be undertaken. If ultrasound demonstrates high-grade stenosis, a confirmatory examination is performed, typically gadolinium-enhanced magnetic resonance angiography (MRA).³¹ If there appears to be a discrepancy between the ultrasound and MRA findings, formal cerebral angiography may be performed.³² There continues to be much controversy regarding what imaging is necessary to establish the diagnosis of carotid stenosis. Ultrasound, MRA, and CT angiography have all been extensively compared with conventional digital subtraction angiography. All modalities have high specificity and sensitivity for detecting carotid stenosis, and MRA in particular may have some added value in detecting other characteristics of atherosclerotic plaque, such as lipid content and intraplaque hemorrhage, among other findings.^33–40

Asymptomatic Patients

Although stroke is the leading cause of death and hospitalization in nearly all European countries and consistently the third major cause of death in the United States, widespread mass screening for carotid occlusive disease is not recommended.^41,42 Whitty and associates argued that screening strategies for asymptomatic carotid stenosis are unlikely to be effective and might even be harmful in populations in which the prevalence is between 1% and 25%.⁴³ The prevalence of moderate asymptomatic carotid stenosis (>50%) in a recent meta-regression analysis published in 2009 was 4.2%, and the prevalence of severe stenosis (>70%) was 1.7%.⁴⁴ Age older than 70 years and male sex increased the chance of finding significant stenosis.⁴⁴ The best screening strategy would involve evaluating patients at high risk for carotid stenosis (based on age, male sex, hypertension, tobacco abuse, peripheral vascular disease) who are surgical candidates and who would undergo surgery if recommended. Identifying this population and the true benefit to them and society as a whole remains highly controversial.^45–51

Symptomatic Patients

As noted earlier, two major trials, NASCET and ECST, have clearly demonstrated the efficacy of CEA in selected patients with amaurosis fugax, hemispheric TIA, or nondisabling stroke within the previous 4 to 6 months.^1,2 Several caveats of the trials are worth noting to guide patient selection.

Asymptomatic Patients

The indications for CEA in asymptomatic patients are much more controversial than those for symptomatic patients despite two very thorough randomized controlled trials.^3,4 ACAS and ACST evaluated the efficacy of CEA in asymptomatic patients, and the results were published in 1995 and 2004, respectively.

Positioning and Exposure

Patients undergo CEA under general anesthesia at our institution. Typically, this is done with a combination of an intravenous muscle relaxant and opioids and inhaled nitrous oxide and isoflurane. All patients are monitored with 16-channel EEG, and the inhaled anesthetic is titrated (usually slightly less than 1 minimum alveolar concentration) so that it does not interfere with the recorded EEG. Patients are positioned supine with their arms tucked at their sides and the head turned to the opposite side and resting on a soft headrest. For obese patients or large barrel-chested men, a rolled blanket placed under the shoulders can assist in the exposure. Some neck extension is very helpful, but in elderly patients, caution must be exercised to avoid overextension in those with possible underlying cervical spondylosis. A curvilinear incision is made parallel to and just posterior to the anterior border of the sternocleidomastoid (SCM) muscle. We have found that placing the incision directly on the anterior border results in a more conspicuous scar, particularly in thin patients. The incision begins about 1 cm below the tip of the mastoid, curves 1 cm below the angle of the mandible, and ends 1 cm above the sternoclavicular joint. A scalpel is used to incise the skin and platysma to expose the cervical fascia (Fig. 350-1). A large transverse cervical sensory nerve might be encountered in the superior portion of the wound and can be sacrificed if necessary. Care should be taken to not violate the parotid fascia, which can be adherent to the upper SCM. Dissection is performed with scissors in a spreading fashion deep to the anterior border of the SCM muscle to free it up from the underlying fascia (Fig. 350-2). The carotid system can then be easily and gently palpated. The cervical fascia is next opened sharply to first expose the common carotid artery. Careful spreading dissection is then continued in a caudal to cephalad direction to expose the carotid bifurcation, external carotid artery (ECA), and ICA. During this dissection, the common facial vein will usually be seen running transversely across the region of the carotid bifurcation (Fig. 350-3). This vein is doubly ligated and divided. The internal jugular vein (IJV) itself rarely needs to be exposed. The omohyoid muscle usually marks the inferior extent of the exposure, and the posterior belly of the digastric muscle marks the superior extent. The hypoglossal nerve (XII) is at risk during the dissection and should be identified and carefully protected. It almost always lies superficial to the ECA and ICA, just below the digastric muscle. The descendens hypoglossi can be seen arising from cranial nerve XII and can be sacrificed; however, we have found this rarely to be necessary. It can almost always be mobilized anterior or posterior to the arteries to provide the needed exposure. Although cutting it seldom has any clinical consequences, if it is going to be sacrificed, it is vital to make sure that it is indeed the descendens hypoglossi and not the vagus nerve. The vagus is almost always deep to the carotid system between the carotid and the IJV (Fig. 350-4). Any dissection deep to the carotid bifurcation should be done very gingerly to avoid injury to the superior laryngeal branch of the vagus nerve, which will result in significant dysphagia postoperatively. We typically use standard fish hooks (Deroyal, Powell, TN) to hold the wound open because they are less obtrusive than self-retaining retractors. Soft vessel loops (Cardinal Health, Chicago) are placed on the common carotid artery and ECA and usually the superior thyroid artery as well. The tape on the ECA should be placed more than a centimeter and preferably 2 cm from its origin from the common carotid artery to facilitate removal of plaque from the orifice of the ECA when the time comes. Great care should be taken when exposing the bifurcation and the proximal ICA, especially in a symptomatic patient, to not dislodge any emboli from the artery.

FIGURE 350-1 The initial skin incision includes the dermis and platysma muscle but should spare the parotid fascia. The deep cervical fascia is easily identified below the platysma.

FIGURE 350-2 Once the anterior border of the sternocleidomastoid muscle is dissected free from the cervical fascia, the carotid system can be gently palpated through the fascia. The wound is held open with fish hooks rather than conventional self-retaining retractors.

FIGURE 350-3 The common, internal, and external carotid vessels are dissected free. The facial vein can be seen crossing the carotid bifurcation and should be doubly ligated and divided. The hypoglossal nerve and descendens hypoglossi are easily visible and carefully protected during the operation. The superior thyroid artery is also identified and controlled. The internal jugular vein is well exposed in this dissection but does not need to be seen extensively.

FIGURE 350-4 Retracting the internal jugular vein laterally exposes the vagus nerve in the deep carotid sheath. This step is necessary only if the descendens hypoglossi is going to be sacrificed to make sure that it is not a wandering vagus nerve before dividing it. The common and external carotid arteries are controlled with vascular tape.

Exposure for a High Bifurcation or Plaque

Occasionally, the surgeon will encounter a patient who has a high carotid bifurcation (above the C3 level) or a plaque that extends high up the ICA. This may require further cephalad exposure of the carotid system. Additional steps in the dissection can easily allow safe exposure of the very distal cervical ICA.⁸¹ The incision can be extended cephalad to the mastoid tip, curved forward and inferior in the postauricular sulcus while skirting the earlobe, and then ascend in the pretragal skin crease. Care needs to be taken again to not incise the fascia over the parotid gland with the skin incision. The posterior border of the parotid gland can then be grasped with forceps and elevated off the upper SCM. If this is continued, the facial nerve can be located just deep to the temporoparotid fascia. With the surgeon’s finger on the mastoid tip and directed anteriorly, its tip overlies the main trunk of the nerve. We fortunately rarely find it necessary to actually expose the facial nerve, even with very high bifurcations. Elevating the parotid further exposes the posterior belly of the digastric muscle and the hypoglossal nerve just deep and inferior to it. The occipital artery often needs to be ligated and divided. The posterior belly of the digastric muscle is then divided between two 2-0 silk sutures and retracted out of the way. These sutures can be tied back together to reapproximate the muscle at the end of the operation, but this is not really necessary. The stylohyoid muscle, which lies parallel and just superior to the digastric muscle, can then be identified and also divided. The deeper stylomandibular ligament then needs to be resected, and the distal ICA lies just below this ligament.⁸¹ Some authors advocate mobilization or resection of a portion of the mandible to aid in the exposure, but we have not found this to be especially helpful or necessary.^82,83

Endarterectomy

Adequate distal exposure of the cervical ICA is crucial for successful completion of the procedure in our opinion, and this cannot be stressed enough. Once the exposure is deemed adequate, the patient is given 5000 IU of intravenous heparin. This will usually result in a doubling of the activated clotting time in most patients. The vascular tapes on the superior thyroid artery and ECA are placed under tension to occlude flow through these vessels and also to elevate the carotid system somewhat out of the neck. Surprisingly little tension is necessary to accomplish this. The patient’s systolic blood pressure is then elevated to 160 to 180 mm Hg, and a soft-shoed Fogarty clamp (Baxter Edwards, Santa Ana, CA) is placed on the proximal common carotid artery. It is important to gently palpate this vessel before placing the clamp to ensure that the clamp is being applied to a soft portion of the artery. It is not necessary to close the Fogarty clamp more than one or two clicks at most. More aggressive use of the clamp could damage the vessel. A curved 12-mm temporary Sugita aneurysm clip (Mizuho, Beverly, MA) is then placed on the distal ICA. We have found this superior to DeBakey clamps or vascular tape. It is less conspicuous in the wound and thus less likely to interfere with the distal endarterectomy and closure of the arteriotomy. It can also easily be removed or opened to test backflow.

An arteriotomy is made in the mid common carotid artery with a No. 11 knife blade and extended up the ICA with Pott’s scissors (Fig. 350-5). The tips of Pott’s scissors will guide the surgeon through the lumen of even the most tightly stenosed artery. The arteriotomy should be extended distally in the ICA until normal intima is obvious (Fig. 350-6). A common initial mistake is to attempt to make a smaller arteriotomy than necessary. The temporary aneurysm clip on the distal ICA is momentarily opened to ensure that backflow is present. The endarterectomy is then begun at the carotid bifurcation, where the plaque is almost always the thickest. The plaque separates from the media of the native artery fairly readily with mild dissection with a small spatula (Fig. 350-7). Dissection is initially carried distally up the ICA. Almost always, the plaque breaks distally from the normal intima with just gentle dissection. Occasionally, if the intima is very thick, a distal intimal break point becomes obvious at the spot where the intima becomes very adherent, and the plaque no longer wants to dissect off the artery. In this case, curved microscissors can be used to trim the plaque distally and create the distal break point. The dissection is then carried proximal into the common carotid artery (Fig. 350-8). The proximal intimal break point is always made with Pott’s scissors once a relatively uniform section of intima is reached (Fig. 350-9). This will create a small “ledge” where the remaining proximal intima meets the endarterectomy site, but this is rarely a concern because it is in the direction of flow. The plaque is then followed up the ECA by circumferentially dissecting it free from the lumen of this vessel (Fig. 350-10). The vascular tape on the ECA can be loosened and the ECA somewhat everted to allow more distal dissection. Once the plaque starts to thin out, it is grasped and removed (Fig. 350-11), thus removing the entire plaque as one specimen (Fig. 350-12).

FIGURE 350-5 An arteriotomy is made in the common carotid artery with a No. 11 knife blade.

FIGURE 350-6 The arteriotomy is extended up the internal carotid artery with Pott’s scissors.

FIGURE 350-7 The atheromatous plaque is dissected free from the media of the artery with a small spatula. The initial cleavage point is best identified at the point where the plaque is the thickest, and it is usually fairly obvious.

FIGURE 350-8 After an appropriate break point is established in the distal internal carotid artery, the plaque is dissected proximally into the common carotid artery.

FIGURE 350-9 There is no natural break point proximally, and the plaque has to be cut sharply from the artery with Pott’s scissors.

FIGURE 350-10 The plaque is circumferentially dissected from the origin of the external carotid artery. Loosening the vascular tape on this vessel will facilitate the dissection and rarely results in a significant amount of bothersome backbleeding.

FIGURE 350-11 Everting the external carotid artery can help dissect the plaque. Once it starts to thin out, it can be grasped with mosquito clamp forceps and removed.

FIGURE 350-12 A standard carotid endarterectomy plaque removed as one specimen.

The endarterectomy bed is then carefully inspected and any remaining filamentous plaque is removed with a small spatula and fine forceps. The distal intimal break point is carefully inspected and copiously irrigated with heparinized saline to ensure that there is no intimal shelf that might serve as a site of dissection or emboli. If there is concern about the distal break point, the arteriotomy can be extended and further dissection carried out to remove additional intima, or the distal intima can be tacked with two or three carefully placed double-armed 7-0 Prolene sutures. The needle is always passed from the inside to the outside of the vessel with both limbs of the suture. Of all the steps in the operation, an adequate distal transition from the endarterectomized vessel to the native intima is the most crucial in obtaining good results. The distal intimal break point has to be smooth and secure or thromboembolic complications can occur and subsequent restenosis is more likely.

Shunt Placement

We place a shunt only if there is a change in the monitored 16-channel EEG ipsilateral to the occluded ICA. This is a very reliable indicator of ischemia (attenuation of faster frequencies of >4 Hz by >50% along with an increase in the amplitude of delta activity by 50%), and when it does occur, we do not hesitate to place a shunt.⁸⁴ Almost always there is time from occlusion to the point when the first change in the EEG occurs to allow proceeding with the arteriotomy and initial dissection of the plaque from the ICA before the shunt has to be inserted. The exception to this strategy is a patient in whom immediate and profound change in the EEG is seen on occluding flow through the ICA. In this case, we perform the arteriotomy and place the shunt right away even before any dissection of the plaque is performed. Placement of a shunt can be somewhat daunting (and bloody) to an inexperienced surgeon and requires good teamwork between the surgeon and assistant. We prefer to use the internal Sundt shunt (Integra, Cincinnati, OH) (Fig. 350-13). A medium-sized shunt (proximal diameter of 3 × 5 mm) works well for most arteries. The proximal end of the shunt is placed first in the common carotid artery. This may require moving the Fogarty clamp more proximal on the artery, which is easily accomplished by holding the artery closed with the thumb and forefinger and simply removing the clamp, sliding it more proximally, and reapplying it to the vessel. The shunt should be flushed with heparinized saline before insertion. After the proximal, larger end is placed in the common carotid artery, the vascular tape around the common carotid is secured around the shunt to hold it in place. A second vascular tape may also be used to ensure that it stays in place. The Fogarty catheter is temporarily opened to flush the shunt with blood and remove any air bubbles. The distal end of the shunt is held with forceps in the surgeon’s dominant hand and the artery is steadied with forceps held in the nondominant hand. The assistant removes the aneurysm clip on the ICA as the surgeon slides the shunt into the distal ICA. The Fogarty clamp is then removed to restore flow up the ICA. Rarely, there may be backbleeding around the shunt from the ICA. Vascular tape placed around the ICA and held secure with a small vascular clip usually controls the backbleeding nicely. If there is a large amount of bleeding from the ICA around the shunt or the EEG does not improve after flow is restored, one should be concerned about the possibility of a distal embolus or occlusion. The arteries need to be reoccluded as the shunt is removed, and backflow from the ICA needs to be checked. If there is no backflow, a Fogarty balloon catheter may need to be passed distally to see whether a clot is occluding the distal cervical ICA.

FIGURE 350-13 The external or loop (longest) and internal (shorter) Sundt shunts.

Once flow is restored through the shunt, the EEG usually improves in minutes. The endarterectomy and closure then proceed as usual. There is no question, in our experience, that the endarterectomy and closure of the arteriotomy are more difficult with the shunt in place, but there is enough gentle movement possible in the shunt to visualize the endarterectomy bed quite well, and it should not compromise the end result.

Removal of the shunt proceeds in the opposite fashion as its insertion. When approximately a centimeter of arteriotomy closure is left, the shunt is grasped with mosquito clamp forceps, occluded, and gently slid out of the distal ICA, and a temporary Sugita clip is applied to the distal ICA, again to stop the backbleeding. The vascular tape on the common carotid artery is loosened and the shunt is carefully slid out of the wound as the Fogarty clamp is reapplied. Undoubtedly, this will again result in significant EEG changes, as it did to signal the need for a shunt in the first place. The arteriotomy should be closed efficiently, but not in a hurried fashion to make sure that a good closure is the final result. Flow is then restored as detailed later.

An external or loop shunt can also be used. This type of shunt has the advantage that it is considerably longer, so it can more easily be mobilized out of the endarterectomy bed to potentially be less obtrusive during the critical portion of the operation. The longer length, however, theoretically increases the risk for thromboembolic complications from the shunt itself. We also find that the loop hangs somewhat out of the field of view of standard 2.5× magnifying loupe glasses and there is a small risk of inadvertently pulling it out of the artery when passing instruments back and forth.

Patch Closure of the Arteriotomy

When a shunt is not required, backflow from the ICA is checked once again, the entire endarterectomy bed is irrigated copiously with heparinized saline, and the endarterectomy bed is inspected once more. We prefer to close the arteriotomy with a knitted Dacron patch (Hemashield Patch Co., Boston Scientific, Wayne, NJ). The distal end of the patch is trimmed to a “V” to match the arteriotomy (Fig. 350-14). It is sewn in with double-armed 5-0 Prolene suture (Ethicon–Johnson & Johnson, Somerville, NJ). The stitch is placed through the apex of the patch and then through the apex of the arteriotomy and tied. A running stitch is then used to close whatever wall of the arteriotomy is most easily done with a forehand stitch first. The initial six or seven stitches have to be placed very precisely to assist in tacking the patch to the native intima. The needle is passed first through the patch and then through the artery in two steps to ensure that placement is precisely where the surgeon wants it. Each suture should be 1 mm deep and 1 mm distal to the previous stitch. Once the endarterectomy site is reached, the patch can be sutured to the artery wall in one throw while taking care to keep the depth and distance between stitches uniform (Fig. 350-15). Closure of the arteriotomy continues until the proximal intima of the common carotid artery is encountered. The proximal end of the patch is then trimmed, and once again it is best to resume placing the sutures in two steps to ensure that the full thickness of the common carotid is engaged with the stitch. Closure continues around the proximal apex of the arteriotomy onto the opposite side. The suture line can then be inspected from inside the artery to make sure that it is uniform (Fig. 350-16). The second arm of the suture is next begun from the apex down the opposite side of the arteriotomy in similar fashion to the first. This can be moderately challenging because it needs to be done in a backhanded fashion to continue to sew from the patch to the artery, and the stiffness of the patch can sometimes make adequate visualization difficult. Patience and a steady hand, however, will guarantee a good, durable closure.

FIGURE 350-14 The knitted Dacron patch trimmed for placement with the apical 5-0 Prolene suture in place.

FIGURE 350-15 The forehand side of the graft is sewn in place first with a running Prolene suture. It is very important to keep the sutures uniform in their depth and distance between sutures.

FIGURE 350-16 The suture line can likewise be inspected from the inside to make sure that it is uniform and there are no clots forming along the suture line.

Primary Closure of the Arteriotomy

Occasionally (<1%), we encounter a patient with a very large ICA and believe that a patch angioplasty is not necessary. In such situations, primary closure is performed. We prefer 6-0 Prolene for this closure. Closure starts at the distal ICA again and proceeds proximally. Once approximately three fourths of the closure is complete, another 6-0 suture is started at the proximal arteriotomy at the common carotid artery and run distally. Restoration of flow proceeds as detailed in the next section and is no different from restoration when a patch is used.

Restoration of Flow

Once the closure has proceeded to within one or two stitches of being complete, systolic blood pressure is lowered to 130 to 150 mm Hg. The ICA is once again backbled to purge the artery of any air (Fig. 350-17). This continues for 8 to 10 seconds and the ICA is reoccluded. The Fogarty clamp on the common carotid artery is then temporarily opened in an attempt to flush any remaining debris and air from the artery (Fig. 350-18). The Fogarty clamp is closed once again and the final stitches are placed. As the two ends of the Prolene suture are tied, flow is restored up the common carotid artery, the tape on the ECA and superior thyroid artery is relaxed to allow flow to first go up the ECA and its branches, and then the aneurysm clip is removed from the ICA to restore flow to the cerebral circulation (Fig. 350-19). Our typical occlusion times range from 30 to 60 minutes. In our experience the EEG is an extremely reliable indicator of ischemia, and if the patient can tolerate 15 minutes of occlusion, hours of occlusion can probably be tolerated and the operation should not be rushed.

FIGURE 350-17 Before tying the last suture, the internal carotid artery is backbled to purge any air or debris from the artery.

FIGURE 350-18 A similar trial for bleeding is performed through the common carotid artery to make sure that all air and debris are out of the artery before the last stitch is tied. A finger over the opening in the artery will prevent anyone in the operating room from getting an unwanted surprise.

FIGURE 350-19 Flow is restored first up the common carotid artery and then the external carotid artery, and finally the clip is removed from the internal carotid artery to restore the cerebral circulation.

It is very common for significant bleeding to arise from several places along the suture line. Almost always, with just gentle pressure from the surgeon’s fingertip and irrigation with warm saline, these areas will spontaneously stop bleeding (Fig. 350-20). Occasionally, a small piece of Gelfoam may help in hemostasis. In rare cases there will be a large enough gap between the stitches that an additional single 6-0 Prolene suture will be required to obtain hemostasis. We seldom reocclude the common carotid artery when we place this stitch. We try to avoid having to place any additional sutures where there is native intima for fear of causing a dissection, but on occasion this may be necessary.

FIGURE 350-20 Final result after endarterectomy, patch closure angioplasty, and restoration of flow.

If there is any question regarding flow through the vessels, a nondisposable, sterile Doppler probe can be brought into the field and the arteries evaluated. The ICA should have a characteristic low-resistance sound, whereas the ECA will have a more brisk, high-resistance signal. If there is still uncertainty, intraoperative ultrasound can be used, but we have not really found this to be necessary. If good flow is not observed through the ECA, as sometimes occurs because of the rather blind, eversion technique used to remove this portion of the plaque, we do not hesitate to further dissect this vessel and its branches, occlude it proximally and distally, and perform a separate arteriotomy in the ECA to make sure that it is free of plaque and patent. This arteriotomy is almost always then closed primarily with 6-0 Prolene. A patent ECA can also be verified by a strong, palpable, ipsilateral superficial temporal artery pulse.

Closure

Once hemostasis of the suture line looks satisfactory, the entire wound is irrigated with saline and meticulous hemostasis is obtained. Hematomas are poorly tolerated in the neck and can result in sudden and severe airway compromise. We usually place a 10 French Jackson-Pratt drain in the neck and close the platysma with interrupted 2-0 Vicryl sutures, approximate the dermis with interrupted 3-0 Vicryl, and close the skin with running 4-0 Vicryl. Some surgeons worry about placing a drain on closed suction next to the arteriotomy site, but we have never found this to cause a problem. Occasionally, the deep cervical fascia can be well identified and closed with running 5-0 Prolene suture, and the drain can be placed superficial to this fascia. Usually, the drain can be removed the morning after surgery.

Postoperative Care

All patients go to the recovery room immediately after surgery and are then transferred to the neuroscience intensive care unit (ICU). Patients who were asymptomatic preoperatively and without complicating comorbid conditions are observed in the intermediate care unit instead. Here, they undergo cardiac rhythm and blood pressure monitoring overnight but otherwise require nursing care only every 4 hours, as opposed to every 1 to 2 hours in the traditional ICU. All patients receive 325 mg of aspirin the night of surgery and daily, indefinitely thereafter. We strongly prefer to not operate on patients taking clopidogrel (Plavix). We have noted increased postoperative bleeding complications that we have not otherwise experienced in patients taking aspirin alone. A soft diet is begun the night of surgery and advanced as tolerated. Patients are encouraged to be up out of bed the evening of surgery. The majority of patients can be discharged from the hospital the day after the operation.

Management of Complications

Management of a few important potential complications after CEA is worth discussing. Strict blood pressure management is imperative to avoid hyperperfusion injury to the brain. This is the primary reason why patients are observed in a hemodynamic monitoring setting postoperatively. We prefer to leave an arterial line in place for the first 24 hours postoperatively. Sustained elevations of mean arterial blood pressure above 15 mm Hg should be aggressively treated with beta blockers or vasodilators as necessary.

Any new postoperative neurological deficit should first be evaluated with non–contrast-enhanced head CT, provided the patient is hemodynamically stable. If no hemorrhage is seen on CT and the patient has a new fixed neurological deficit, we believe that formal cerebral angiography should be performed to look at the endarterectomy site, evaluate the collateral circulation, and inspect for any intracranial emboli. If the endarterectomy is patent and there is evidence of distal emboli, we use heparin anticoagulation to try to reduce the risk for additional thromboembolic complications.

If acute occlusion of the ICA is discovered on the angiogram, we return to the operating room directly to try to restore flow through the artery. Fortunately, this has been extremely rare but may require complete removal of the Dacron patch and substitution of an autologous saphenous vein patch.

Finally, it should be emphasized that a postoperative neck hematoma in a CEA patient is a neurosurgical and anesthesia emergency. Although it is tempting to open the neck immediately in the ICU when a postoperative patient is discovered with an expanding hematoma and pending airway comprise, we discourage this practice. It is unlikely that enough clot can be evacuated with the rudimentary instruments available in the ICU, and significant bleeding can be encountered. Additionally, the anesthesia team will have a much better chance of securing the airway in the operating room. Simultaneously, the otolaryngology team should be alerted to come to the operating room in the event that a difficult tracheostomy needs to be performed on an emergency basis if the airway cannot be secured expeditiously. Once the patient is reintubated, the surgical incision can be reopened under sterile and controlled conditions and any bleeding arrested. In our limited experience it is rare to actually find the bleeding source that caused even a large life-threatening hematoma.