Carotid endarterectomy and local anaesthesia: reducing the disasters

PURPOSE: The study was designed to assess one surgeon's operative mortality and morbidity for carotid endarterectomy using local anaesthetic (LA) compared to general anaesthetic (GA) techniques. METHOD: Data were collected prospectively from 200 patients undergoing LA carotid surgery compared with 243 patients undergoing carotid surgery using GA technique. Indication for surgical, pathology, postoperative morbidity and mortality was assessed. RESULTS: No major strokes or deaths occurred in the LA group (0/200). Significantly more major strokes and/or deaths occurred in the GA group (11/243, 4.5%; P=0.016). Significant less shunt usage was associated with LA (LA 18/200, 9% versus 94/243, 39%; P=0.001). The absence of a shunt was associated with more major events in the GA group (5/143, P=0.001. Age greater than 74 yr was associated with greater major events (4/31, P=0.002). No significant difference in the frequency of cardiovascular complications was observed (LA, 15/200 (7.5%) vs GA, 19/243(7.8%); P=0.924). CONCLUSION: Local anaesthesia enables the surgeon to assess the level of cerebral perfusion with an awake patient, gives greater assurances of cerebral protection during arterial clamping and a provides for a more relaxed and cautious endarterectomy and repair. This study demonstrates reduction in mortality and major stroke events in patients operated on with these conditions.     

Carotid endarterectomy improves cognitive function in patients with exhausted cerebrovascular reserve.

OBJECTIVE: To investigate changes in cognitive function following carotid endarterectomy (CEA). DESIGN: Prospective study with controls. METHODS: CEA patients (n=159) were compared to a urology surgery control group (n=20). In CEA patients cerebrovascular reserve (CVR) was measured preoperatively. During surgery emboli and blood flow velocity in the middle cerebral artery were measured by transcranial Doppler (TCD) and cerebral oxygen saturation (CsO2) by near infrared spectroscopy. Cognitive function was measured preoperatively and at 5 days and 8 weeks postoperatively using a standardised computer battery of tests. RESULTS: Only 8% of patients had normal CVR bilaterally. The median number of emboli during CEA was 12 (range 0-181). On carotid clamping, TCD velocity fell a median of 41% and cerebral oxygen saturation by 5%. Attention deteriorated compared to controls 5 days following CEA (p=0.003) and this deterioration was related to the rise in TCD velocity on declamping (r=-0.3, p=0.002). Median attention reaction times improved significantly by 8 weeks (p=0.001) especially in patients' with severely impaired CVR before surgery (p=0.02). CONCLUSIONS: Attention improved at 2 months following CEA in patients with impaired CVR. CEA may offer more than reduced stroke risk to patients with impaired CVR.     

Carotid endarterectomy in the elderly

The records of 146 patients 80 years of age or older who underwent 183 carotid endarterectomy operations from 1964 through 1990 were reviewed to determine surgical risk. The indications for operation were asymptomatic patients with carotid stenosis (n=36); ipsilateral transient ischemic attacks (n=46); ipsilateral stroke (n=28); ipsilateral retinal embolus (n=15); nonlateralizing symptoms (n=40); and asymptomatic side in patients with contralateral symptoms (n=18). Postoperatively, three patients (1.6% of operations) had a stroke with a residual deficit and three (1.6%) died. All deaths were from myocardial infarction. For comparison, during the same time period, the combined stroke with residual deficit and death rate for patients less than 80 operated upon for similar indications was 3.5%. Since 80-year-old patients have a life expectancy of at least five years, the authors conclude that elderly patients should be evaluated for carotid endarterectomy using criteria similar to that used for younger patients.Presented at the Tenth Annual Meeting of the Southern California Vascular Surgical Society, September 27–29, 1991, Marina Del Rey, California.     

Carotid endarterectomy in the octogenarian

During a 10-year period from January 1983 to December 1992, 79 carotid endarterectomies were performed in patients aged 80 years or older. This represented 7.4% of the total patient population undergoing carotid endarterectomy at Emory University Hospital. The indications for surgery in this elderly population were transient ischemic attacks in 24 (30.3%), cerebrovascular accident in 12 (15.2%), amaurosis fugax in seven (8.9%), vascular tinnitus in one (1.3%), and asymptomatic stenosis in 35 (44.3%). The average degree of ipsilateral stenosis was 76.8%. Concomitant risk factors included coronary artery disease in 43%, systemic arterial hypertension in 51.9%, diabetes mellitus in 10.1%, and significant smoking history in 53.2%. Seventy-six percent of the procedures were performed under local anesthesia, and in all but two intraluminal shunts were used. Combined 30-day mortality and postoperative stroke morbidity in this population was 1.3% (one patient). Long-term follow-up ranging from 1 to 10 years (average 35 months) revealed no ipsilateral strokes. This experience suggests that carotid endarterectomy can be performed in an elderly population with morbidity and mortality rates similar to those in a younger cohort.Presented at the Fourth Annual Winter Meeting of the Peripheral Vascular Surgical Society, Breckenridge, Colo., January 21– 24, 1994.     

Carotid endarterectomy in the elderly

The elderly population has the highest risk for developing stroke and the annual death rate is some 394/100,000 population. Moreover, the elderly are the fastest growing segment in our society. In carefully selected patients carotid endarterectomy may provide to prophylaxis against stroke. With a careful selection, acceptable low operative motality and morbidity rates may be achieved, comparable to the 4.3% and the 2.3% of the Veterans Affair and ACAS studies, in which the patients' mean ages were 64.1 and 67 years respectively.     

Carotid endarterectomy using the eversion technique

Carotid endarterectomy by the eversion technique allows for all of the benefits of conventional endarterectomy but obviates the need for a distal suture line on the smaller internal carotid artery, and thus batching. Carotid artery reanastomosis onto the bifurcation can be quickly and simply performed with almost no risk of closure-related restenosis, given the anastomosis is on the larger of 2 arteries. In our experience of over 3,000 eversion carotid artery endarterectomies, the restenosis rate has been less than 1% judged by rigorous duplex follow-up. In this article, the technique and utility of eversion carotid endarterectomy is discussed.     

Carotid endarterectomy remains the gold standard

BACKGROUND: To compare the safety and efficacy of carotid endarterectomy (CEA) as performed in a community medical center with the Asymptomatic Carotid Atherosclerosis Study (ACAS) and North American Symptomatic Carotid Endarterectomy Trial (NASCET) standards and with representative published results regarding carotid angioplasty and stenting (CAS). METHODS: Between 1 January 1994 and 31 July 2000, 267 CEA procedures were performed on 236 patients at Madigan Army Medical Center (MAMC). Prospectively acquired patient demographics, operative indications, and surgical outcomes were reviewed using clinical records, carotid duplex evaluations, and follow-up examinations. The resultant data were compared with ACAS, NASCET, and published results of CAS. RESULTS: The perioperative stroke rate was 2.2% (6 of 267) overall, 0.7% (1 of 139) among asymptomatic patients, and 3.9% (5 of 128) among symptomatic patients. There were no perioperative deaths from any cause in the entire series. The respective ACAS and NASCET early stroke-death rates were 2.3% (19 of 825) and 5.8% (19 of 328). The largest published series of CAS reported stroke-death rates of 5.7% (299 of 5,210) overall, and 3.4% (46 of 1,361) and 5.8% (93 of 1,614) for asymptomatic and symptomatic patients, respectively. CONCLUSIONS: CEA remains the standard of care. It is a safe, effective, and durable procedure that can be performed in a facility such as MAMC with outcomes that compare favorably with ACAS and NASCET. Results of CEA at MAMC are superior to similar data regarding CAS. Widespread use of CAS should be deferred pending completion of on-going prospective trials versus CEA.     

Carotid endarterectomy in the awake patient

The advantages of performing carotid endarterectomy in the awake patient have been presented based on a 13 year experience. Anesthesia consisted of either local infiltration of local lidocaine or regional neck block supplemented by intravenous sedation. The principal advantages of the technique are that it is the only exact method of assessing the need for an intraluminal shunt by neurologic assessment of the awake patient during trial carotid cross-clamping, and the elimination of general anesthesia allows carotid endarterectomy to be safely performed on patients with advanced inoperable coronary artery disease and in those with chronic obstructive pulmonary disease. One hundred consecutive carotid endarterectomies have been reported with one late death and one mild, permanent neurologic deficit. These results support the belief that carotid endarterectomy can be performed with very low morbidity and mortality rates by operating on the awake patient.     

Carotid endarterectomy complicated by vein patch rupture.

Saphenous vein patch angioplasty has been used to improve the results of carotid endarterectomy by decreasing the incidence of postoperative occlusion and recurrent stenosis. A rare but potentially lethal complication of this technique is aseptic necrosis and rupture of the vein patch during the postoperative period. We report three cases of this phenomenon and review an additional 13 cases from the literature. This event generally occurs without warning 2 to 7 days postoperatively and may result in death or stroke. At reoperation, the central portion of the vein patch is necrotic, without evidence of infection. Technical considerations in the harvesting and preparation of these grafts are reviewed, as are the physical parameters predisposing certain vein patches to rupture. Saphenous vein harvested from the ankle has been linked to every reported case. Small diameter veins in particular appear to carry a higher risk of rupture.     

Carotid endarterectomy: a study of cerebral oxygen saturation vs stump pressure

BACKGROUND AND AIMS: Carotid endarterectomy (CEA) is an established surgical procedure for treatment of internal carotid artery (ICA) stenosis. To determine whether or not a carotid shunt is necessary to place, some surgeons measure the stump pressure. We conducted the current study in order to identify whether or not cerebral oxygen saturation (rS02%) can serve as another quantitative measurement to determine the need of carotid shunt during CEA. MATERIALS AND METHODS: Ten patients who underwent CEA under general anesthesia were studied. The stump pressure was measured during ICA clamping and rSO2% was measured during three phases: A) prior to ICA clamping, B) during ICA clamping and C) after ICA declamping. The data were subjected to one-way ANOVA and correlation coefficient analysis. The mean age was 62+/-7 yr and the mean body weight was 66+/-7kg. RESULTS: The stump pressure and rSO2% mean values were 45+/-9 mmHg and 57+/-7% respectively during ICA clamping. Correlation coefficient revealed significant positive relationship, r = 0.724(P = 0.009). CONCLUSIONS: rSO2% may serve as another quantitative measurement to determine the need for carotid shunt during CEA surgery. Due to the small number of cases in the current study, the critical rSO2% which warrants carotid shunt placement could not be identified. Therefore, large number of patients are required to define the critical rSO2% during CEA surgery.     

Carotid sinus nerve blockade to reduce blood pressure instability following carotid endarterectomy: a systematic review and meta-analysis.

OBJECTIVES: Local anaesthetic infiltration into the carotid sinus during carotid endarterectomy (CEA) has been recommended to minimise blood pressure fluctuations but its use remains controversial. The aim of this meta-analysis was to determine whether intra-operative administration of local anaesthetic reduces the incidence of haemodynamic instability following CEA. MATERIALS AND METHODS: A search of the Medline, Pubmed and Embase databases and the Current Controlled Trials register identified four trials, which met the pre-defined inclusion criteria for data extraction. Pooled odds ratios with 95 per cent confidence intervals (c.i.) for the development of post-operative hypotension and hypertension were calculated using a random-effects model. RESULTS: Outcomes of 432 patients were studied. Local anaesthetic blockade of the carotid sinus was associated with a pooled odds ratio of 1.25 (95 per cent c.i. 0.496 to 3.15); p=0.216) and 1.28 (95 per cent c.i. 0.699 to 2.33; p=0.428) for the development of post-operative hypotension and hypertension respectively. Although none reach significance there was a trend towards increased risk of developing a complication in those patients who received local anaesthetic. CONCLUSIONS: There are insufficient data to determine the role of intra-operative local anaesthetic administration in reducing post-operative blood pressure lability following CEA. Conversely, the possibility of harm cannot be excluded on the basis of the currently available data.     

Carotid endarterectomy, siphon stenosis, collateral hemispheric pressure, and perioperative cerebral infarction

To determine whether moderate stenosis (50% to 80%) of the intracranial segment of the internal carotid artery increases the risk of cerebral infarction after carotid endarterectomy, the arteriograms, ocular pneumoplethysmograms, internal carotid back pressure, and clinical outcome after 169 operations were reviewed. Siphon stenoses less than 50% were not included because of their doubtful anatomic and hemodynamic significance. No patients with stenosis greater than 80% underwent operation. Moderate siphon stenosis affected 37 vessels, 24 (14.2%) ipsilateral and 13 (7.6%) contralateral to the side of operation. Eight patients had bilateral siphon stenosis. Three patients had stroke after operation; none of these cases had siphon stenosis. Moderate siphon stenosis did not increase the risk of perioperative cerebral infarction. Stroke only occurred in those patients in whom there was arteriographic or functional evidence that the affected hemisphere was isolated from effective collateral vessels.     

Carotid endarterectomy. One solution to the stroke problem

Stroke is most often the result of extracranial cerebral artery disease; stroke carries a high initial mortality and morbidity and portends an increased risk of subsequent stroke or myocardial infarction. Stroke is also a preventable disease in more than one half of patients, either by approximate treatment of premonitory transient ischemic attacks or by appropriate evaluation of otherwise asymptomatic carotid bruits. Combined patient education and referring physician awareness should result in a declining incidence of stroke in this country. Two hundred carotid endarterectomies were performed over a 4-year period by senior residents under the direct supervision of the authors. Operative mortality was 1.5 per cent; perioperative stroke, 1.5 per cent; temporary neurologic deficit, 1 per cent; and temporary cranial nerve injury, 1 per cent. Analysis of these patients and of the literature supports an aggressive approach to carotid endarterectomy for patients with focal transient ischemic attacks and a more cautious approach for patients with prior stroke or asymptomatic stenoses.     

Carotid endarterectomy without a shunt: the control series

Nine hundred forty carotid endarterectomies were performed without the use of a temporary indwelling shunt. Six patients (0.6%) died, all from stroke; 17 other patients (1.8%) had another stroke, and 21 patients (2.2%) had temporary neurologic symptoms. Complete x-ray films detailing the opposite internal carotid artery and carotid artery back pressure were available for 783 operations. Correlation of stroke to back pressure, status of the contralateral internal carotid artery, preoperative neurologic deficit, and carotid clamp time was examined. Statistical analysis demonstrated significantly increased neurologic complications only if the systolic carotid back pressure was less than or equal to 50 mm Hg or the contralateral internal carotid artery was occluded. Analysis to determine if these factors were dependently related showed that when both a contralateral carotid occlusion and a carotid back pressure of less than or equal to 50 mm Hg coexisted (82 patients), the rate of permanent deficit was 11.0% compared with 2.8% when either factor was singly present and 0.9% when neither factor was present. No statistical difference exists between the group with only a single factor and those with neither factor. When a temporary shunt is not used during carotid endarterectomy, the risk of neurologic complication is increased if both a contralateral internal carotid artery occlusion and a carotid back pressure of less than or equal to 50 mm Hg coexist. The use of a shunt in this patient population may be beneficial.     

Carotid endarterectomy results in the early years of practice

BACKGROUND: Newly qualified surgeons, as well as their referring physicians, are understandably anxious when dangerous surgery is contemplated. Carotid endarterectomy (CEA), which requires a low morbidity/mortality rate to be successful, is especially problematic in this realm. There is a paucity of literature indicating the results that can be expected when a less-experienced surgeon is asked to perform this procedure. As the volume of CEA surgery is expected to decrease in the future with improvements in endovascular techniques, there will be fewer highly experienced CEA surgeons around.METHODS: We studied the first consecutive, prospectively recorded 100 CEAs performed by each of two newly qualified surgeons (200 total) between January 1993 and May 1998. Standard technique was used and all cases were done under general anesthesia. The only difference in technique was the more liberal use of shunting and protamine by one individual.RESULTS: There were no significant differences in the patient demographics between the two surgeons. Seventy-five percent of the cases harbored symptomatic stenoses. An overall combined stroke/mortality rate of 5.5% was observed. The rate in those operated on for symptomatic stenosis (n = 150) was 6% while it was 4% for those with asymptomatic pathology. There were no significant differences in outcome between the two surgeons. The average stroke/mortality rate in the first 50 cases for each surgeon was 7%, as opposed to 4% for the second 50 cases.CONCLUSIONS: These data indicate that less-experienced individuals can perform this procedure with good results.     

Carotid endarterectomy by eversion technique: its safety and durability.

SUMMARY BACKGROUND DATA: The outcome of standard longitudinal carotid endarterectomy (CEA) can be measured by preservation of neurologic function with a low incidence of restenosis. Closure of the internal carotid arteriotomy with or without a patch may predispose to restenosis. Alternatively, transection of the internal carotid artery at the bulb with eversion endarterectomy allows expeditious removal of the plaque and direct visualization of the endpoint. Because the proximal internal carotid artery is anastomosed to the common carotid artery, this obviates the need for patch closure. The authors report their results with this technique in more than 2200 procedures. METHODS: From May 1993 to March 1998, 1855 patients underwent 2249 CEAs using the eversion technique. During the same period, 410 patients had 474 CEAs by standard technique. Three hundred fifteen procedures in the eversion group and 65 procedures in the standard group were combined CEA and coronary artery bypass grafts. Most solo CEAs (97%) were performed in awake patients using regional anesthesia. Shunts were used on demand in 6% of CEAs. RESULTS: The operative mortality rate was 1.02% (16/1575) in the solo eversion group and 2.2% (9/410) in the standard group. There were 18 permanent neurologic deficits (0.8%) in the eversion group and 11 (2.3%) in the standard group. Transient neurologic deficits occurred in 20 patients (0.9%) in the eversion group and 13 patients (2.7%) in the standard group. Of the 1855 patients, 1786 (96%) presented for duplex ultrasound follow-up. There were seven (0.3%) stenoses greater than 60% in the eversion group versus five (1.1%) in the standard group. CONCLUSIONS: Eversion CEA can be performed safely with a low rate of stroke and death and a minimal restenosis rate in short- and long-term follow-up.