Examination of the interaction between method of anesthesia and shunting with carotid endarterectomy

What Is the Best Technique for Treating Carotid Disease?

This is a comprehensive review of carotid artery revascularization techniques: Carotid Endarterectomy (CEA), Transfemoral Carotid Artery Stenting (TFCAS), and Transcarotid Artery Revascularization (TCAR). CEA is the gold standard and is particularly effective in elderly and high-risk patients. TFCAS, introduced as a less invasive alternative, poses increased periprocedural stroke risks. TCAR, which combines minimally invasive benefits with CEA's neuroprotection principles, emerges as a safer option for high-risk patients, showing comparable results to CEA and better outcomes than TFCAS. The decision-making process for carotid revascularization is complex and influenced by the patient's medical comorbidities and anatomic factors.

Effectiveness of carotid council in the treatment of carotid artery disease: Early-term outcomes of the multidisciplinary approach

OBJECTIVES

Carotid arterial stenosis could be treated by surgical or percutaneous stenting. In this study, we aimed to investigate the effectiveness of the carotid council on the outcomes of patients with carotid artery disease.

METHODS

In this retrospective study, we analyzed the patients who had undergone carotid arterial revascularization from April 2014 to July 2022 in our hospital. All patients were evaluated in carotid council, which is constituted by neurologist, cardiologist and cardiovascular surgeon. Patient-specific treatment procedure was decided in the council. Demographics and early-term follow-up results of the patients were evaluated.

RESULTS

Totally 95 procedures in 85 patients were analyzed during the study period. 27.4 % of the patients had significant contralateral carotid arterial stenosis. In 88 (92.6%) procedures, patients were treated by carotid endarterectomy, and 5 procedures were performed under regional anesthesia. Shunt usage was 6.0% during the surgery, and arteriotomy was repaired with primary sutures in 87.3%. Stent implantation was performed in 7 patients. There were 5 neurological adverse events after the carotid endarterectomy and 2 neurological events were after carotid arterial stenting. In each treatment group, one patient died after the procedure. In the follow-up period, restenosis was observed just in a patient who was treated with carotid endarterectomy and primary repair.

CONCLUSION

Although carotid artery disease could be treated in accordance with the guidelines, treatment procedures should be patient-specific. Carotid councils might be helpful in giving patient-specific decisions, thereby providing the patient-based treatment procedure and improving the outcomes of the patients with carotid artery disease.

Cerebral oximetry monitoring by means of INVOS-4100 as a predictor of ischemic events during carotid endarterectomy

Background

Several methods have been proposed to monitor cerebral perfusion during carotid endarterectomy (CEA), with the purpose of minimizing the risk of perioperative stroke. The INVOS-4100 is able to detect cerebral oxygen saturation providing an intraoperative real-time monitoring system of cerebral oximetry. The aim of this study was to evaluate the performance of the INVOS-4100 in predicting cerebral ischemia during CEA.

Methods

Between January 2020 and May 2022, 68 consecutive patients were scheduled for CEA either under general anesthesia or regional anesthesia with deep and superficial cervical block. Vascular oxygen saturation was recorded continually through INVOS before and during clamping of the ICA. Awake testing was performed in the group of patients undergoing CEA under regional anesthesia.

Results

Sixty-eight patients were included; 43 were males (63.2%). Severe stenosis of the artery was present in 92%. Forty-one (60.3%) patients were monitored by INVOS, while 22 (39.7%) underwent awake testing. Mean clamping time was 20 ± 6.6 min. Patients undergoing awake testing had a lower hospital stay and ICU stay during admission (p = 0.011 and p = 0.007 respectively). Comorbidities correlated with a higher ICU stay (p < 0.05). The INVOS monitoring was able to predict ischemic events with a sensitivity of 98% (AUC = 0.976).

Conclusions

The present study demonstrates that cerebral oximetry monitoring was a strong predictor of cerebral ischemia, although it was not possible to determine the non-inferiority of cerebral oximetry compared to awake testing. Nonetheless, the use of cerebral oximetry evaluates only perfusion in the superficial brain tissue and an absolute rSO2 value corresponding to significant cerebral ischemia has not been established. Therefore, larger prospective studies that correlate cerebral oximetry with neurologic outcomes are needed.

A systematic review & meta-analysis on perioperative cerebral and hemodynamic monitoring methods during carotid endarterectomy

OBJECTIVE

To compare outcomes between different strategies of perioperative cerebral and hemodynamic monitoring during carotid endarterectomy.

DATA SOURCES

MEDLINE, EMBASE, CINAHL, and Cochrane CENTRAL databases were searched.

METHODS

This review was performed according to the PRISMA guidelines and prospectively registered in the international prospective register of systematic reviews (CRD42021241891). The GRADE approach was used to describe the methodological quality of the studies and certainty of the evidence. The primary outcome was 30-day stroke rate. Secondary outcomes measures are 30-day ipsilateral stroke, 30-day mortality, shunt rate and complication rates.

RESULTS

The search identified 3 460 articles. Seventeen RCTs, three prospective observational studies and seven registries were included, reporting on 236 983 patients. The overall pooled 30-day stroke rate is 1.8% (95% CI 1.4 - 2.2%), ranging from 0 - 12.6%. In RCT's the pooled 30-day stroke rate is 2.7% (95% CI 1.6 - 3.7%) compared to 1.3% (95%CI 0.8 - 1.8%) in the registries. The overall stroke risk decreased from 3.7% before the year 2000 to 1.6% after 2000. No significant differences could be identified between different monitoring and shunting strategies, although a trend to higher stroke rates in routine no shunting arms of RCTs was observed. Overall 30-day mortality, myocardial infarction and nerve injury rates are 0.6% (95%CI 0.4 - 0.8), 0.8% (95%CI 0.6-1.0) and 1.3% (95%CI 0.4-2.2), respectively.

CONCLUSIONS

No significant differences between the compared shunting and monitoring strategies are found. However, routine no shunting is not recommended. The available data is too limited to prefer one method of neuromonitoring over another method when selective shunting is applied.

A single-center retrospective study with 1-year follow-up after CEA in patients with severe carotid stenosis with contralateral carotid artery occlusion

Objective

To analyze the risk factors associated with adverse events after carotid endarterectomy (CEA) in patients with unilateral severe carotid stenosis and contralateral occlusion.

Methods

Patients were recruited for CEA between August 2014 and February 2020. CEA was performed under general anesthesia. The carotid clamp time (CCT; long CCT: >20 min) is defined as the period between clamp-on and clamp-off for the stenotic carotid artery. The perioperative factors and postoperative adverse events were recorded. All patients were followed up for 1 year after CEA.

Results

Sixty subjects (65.8 ± 7.2 years; 54 males) were included. Patients with adverse events had significantly longer CCT than those without adverse events (60% vs. 40%, P = 0.013). Univariate logistic regression analysis showed that a history of diabetes was significantly associated with adverse events (OR, 0.190; 95% CI, 0.045–0.814; P = 0.025); long CCT was significantly associated with adverse events (OR, 8.500; 95% CI, 1.617–44.682; P = 0.011). After adjusting for confounding factors, including age, sex, BMI, diabetes, PSV, long CCT, non–use of shunt, and history of stroke or TIA, the associations between diabetes and adverse events (OR, 0.113; 95% CI, 0.013–0.959; P = 0.046) were statistically significant; the associations between long CCT and adverse events (OR, 1.301; 95% CI, 1.049–1.613; P = 0.017) were statistically significant.

Conclusions

A longer carotid clamp time (>20 min) and a history of diabetes may increase the risk of adverse events in patients with unilateral severe carotid stenosis and contralateral occlusion after CEA. With good preoperative evaluation and intraoperative monitoring, the use of shunts may not be needed intraoperatively in patients with unilateral severe carotid stenosis and contralateral occlusion.

Outcomes and role of shunting during carotid endarterectomy for symptomatic patients

OBJECTIVE

Shunt placement during carotid endarterectomy (CEA) is often advocated to protect the ischemic penumbra in patients with symptomatic carotid stenosis. This study assesses the effect of shunt placement on postoperative stroke risk in symptomatic patients undergoing CEA.

METHODS

We queried the American College of Surgeons National Surgical Quality Improvement Program database (2016-2019) for CEA cases with complete CEA procedure-targeted data. Symptomatic patients were identified as having a preoperative diagnosis of stroke on presentation (DS), transient ischemic attack (TIA), amaurosis fugax (AF), or temporary monocular blindness (TMB). DS patients were further analyzed according to the severity of their stroke based on their modified Rankin Scale (mRS). To better assess the effect of shunt placement on stroke rate, we compared cases of CEA with patch angioplasty technique, with and without the use of intraoperative shunt. Patients who underwent carotid eversion or primary closure were excluded. Baseline demographics and perioperative outcomes were compared using Chi-square and Mann-Whitney U test. Multivariate analysis was performed to identify independent risk factors for postoperative stroke and cranial nerve injury.

RESULTS

We identified 4,652 cases of CEA with patch angioplasty in symptomatic patients, including 1,889 (40.6%) with shunt placement and 2,763 (59.4%) without. Age, race, and sex distributions were similar for both procedures. Compared to patients without shunt, those with shunt had significantly higher rates of emergency (9.1% vs 7.0%, P = .010) and non-elective surgery (40.3% vs 37.2%, P = .035), general anesthesia (97.0% vs 86.3%, P < .001), and bleeding disorders (27.2% vs 22.7%, P < .001). Thirty-day incidence of postoperative stroke was similar between patients who had shunt placement (3.2%) and those who did not (2.6%) (P = .219). Additionally, subgroup analysis failed to show any benefit of shunting on postoperative stroke regardless of preoperative symptoms or neurologic disability. In contrast, shunt placement was associated with increased rate of cranial nerve injury (4.1% vs 2.4%, P = .001). Multivariate analysis revealed that non-elective surgery (OR 1.99, 95% CI 1.36-2.91, P < .001) and DS (vs TIA/AF/TMB) (OR 1.64, 95% CI 1.12-2.41, P = .012) were predictive of 30-day postoperative stroke. After adjusting for confounders, shunt placement had no effect on stroke risk at 30 days but remained an independent risk factor for cranial nerve injury (aOR 1.87, 95% CI 1.32-2.64, P < .001).

CONCLUSIONS

In symptomatic patients undergoing CEA with patch angioplasty, shunting is associated with increased risk of cranial nerve injury without reduction in postoperative stroke risk.

Risk for Additional Infarction in Emergency Carotid Artery Endarterectomy in Thrombectomy Acute Stroke Patients

Purpose: Thromboembolic occlusion of the middle cerebral artery with tandem occlusion of the internal carotid artery is a life-threatening condition with unfavorable neurological outcome. We perform emergency carotid endarterectomy in the same anesthesia session as thrombectomy in our angiography suite whenever needed despite the absence of electrophysiological neuromonitoring. Methods: We evaluated 47 thrombectomy patients with emergency CEA in our clinic between June 2013 and November 2020. To determine whether there were additional infarctions due to the surgical procedure, we assessed the initial diagnostic CT imaging for previously infarcted areas, cerebral perfusion, and vascular anatomy, including collateralization in the Circle of Willis (CoW). We then analyzed follow-up imaging with respect to new infarctions that could not be explained by the initial stroke. Results: 5 of 47 (11%) patients had a complete CoW. There was contralateral internal carotid artery (ICA) stenosis or occlusion in 18/47 (38%) patients. Surgical procedure was eversion CEA in 34 (72%) and with a patch graft CEA in 13 (28%) cases. Shunts were used during surgery in 17/47 (36%) patients. Two patients suffered from an additional infarction in a new territory, however this was not caused by the surgical procedure but due to embolism during endovascular thrombectomy. In 1 of these 2 patients a hemodynamic border zone infarction was also observed, which could have developed during thrombectomy as well as during surgery, although this could not be attributed with absolute certainty to the surgery. The final infarction size was significantly larger in patients with contralateral ICA stenosis or occlusion ( P = .038). Neither CoW anatomy nor the absence of a shunt during surgery could be identified as risk factors for additional infarction. Conclusion: Emergency surgery in the angiography suite without neuromonitoring was not associated with an increased additional stroke rate in our patient cohort.

The Diagnostic Accuracy of Intra-Operative Near Infrared Spectroscopy in Carotid Artery Endarterectomy Under Regional Anaesthesia: Systematic Review and Meta-Analysis

OBJECTIVE

Intra-operative near infrared spectroscopy (NIRS) is a non-invasive tool used to monitor regional cerebral oxygen saturation during carotid endarterectomy (CEA), for which accuracy remains unclear. Therefore, this systematic review and meta-analysis aimed to determine the diagnostic accuracy of NIRS in patients undergoing CEA under regional anaesthesia (RA).

DATA SOURCES

MEDLINE, Scopus, and Web of Science were searched for studies that compared NIRS with the "awake test" in patients undergoing CEA under RA.

REVIEW METHODS

Bivariable random effects meta-analysis was performed to determine the diagnostic accuracy of NIRS to detect cerebral ischaemia. Meta-regression was performed to explore causes of heterogeneity. Meta-analysis of proportions was also performed to determine the accuracy of NIRS in predicting 30 day stroke. Study quality was evaluated using the QUADAS-2 criteria.

RESULTS

Eleven primary studies were included, assessing 1 237 participants. The meta-analysis obtained a partial area under the summary receiver operating characteristic curve for diagnosing brain ischaemia of 0.646, with a summary sensitivity of 72.0% (95% confidence interval [CI] 58.1 - 82.7; I² = 48.6%) and a specificity of 84.1% (95% CI 78.5-88.4; I² = 48.6%). In meta-regression analysis, the frequency of hypertension (p = .011) and patients with symptomatic carotid stenosis (p = .031) were significant effect modifiers. Higher frequency of arterial hypertension (z score = -2.15; p = .032) and diabetes (z score = -2.12; p = .034) were associated with lower summary sensitivity, while a higher frequency of symptomatic carotid stenosis (z score = 2.11; p = .035) was associated with higher summary sensitivity. Point estimate sensitivity and specificity for predicting 30 day stroke occurrence were 41% (95% CI 19.5 - 66.6; I² = 0%) and 81.4% (95% CI 74.4 - 86.9, I² = 65.6%), respectively.

CONCLUSION

The results of this study suggest that NIRS as a cerebral monitoring technique does not have sufficiently high sensitivity or specificity to be used alone in the neurological monitoring of patients undergoing CEA under RA.

Outcomes of Carotid Revascularization in Patients with Contralateral Carotid Artery Occlusion

BACKGROUND

Little is known about the best revascularization procedure for patients with contralateral carotid artery occlusion (CCO). We aim to compare the outcomes of transcarotid artery revascularization (TCAR), carotid endarterectomy (CEA), and transfemoral carotid artery stenting (TFCAS) in patients with CCO.

STUDY DESIGN

Patients in the Vascular Quality Initiative dataset who underwent CEA, TFCAS, or TCAR, and had CCO between September 2016 and April 2020, were included. Multivariable logistic analysis was used to evaluate in-hospital outcomes.

RESULTS

The final cohort included 1,144 TCARs, 1,182 TFCAS, and 2,527 CEA procedures performed in patients with CCO. Compared with TFCAS, TCAR was associated with a significant reduction in the odds of in-hospital stroke or death (odds ratio [OR] 0.26; 95% CI: 0.12-0.59; p < 0.01). However, no significant difference in stroke was noted (OR 0.71; 95% CI 0.34-1.51; p = 0.38). These results persisted after stratifying with respect to symptomatic status (p values of interaction = 0.92 and 0.74, respectively). There was no significant difference between TCAR and CEA in odds of in-hospital stroke or death on multivariable adjustment (OR 0.57; 95% CI: 0.29-1.10, p = 0.10). The interaction between procedure type and symptomatic status in predicting in-hospital stroke was statistically significant (p = 0.04). In asymptomatic patients, TCAR was associated with a 50% to 60% reduction in the odds of stroke (p = 0.04). Yet, no significant differences were observed in symptomatic patients.

CONCLUSIONS

TCAR has lower odds of in-hospital stroke or death compared to TFCAS, independent of symptomatic status. Compared to CEA, TCAR seems to be a better option in asymptomatic patients, with lower odds of in-hospital stroke. Yet, no significant difference is observed in symptomatic patients.

Practice patterns in the use of completion imaging after carotid endarterectomy

BACKGROUND

The use of intraoperative completion imaging (completion carotid duplex ultrasound or angiography) to confirm the technical adequacy of carotid endarterectomy (CEA) remains a matter of controversy. The purpose of this study was to describe vascular surgeons' practice patterns in the use of completion imaging after CEA and to study the association between completion imaging and postoperative stroke/death and high-grade restenosis (>70%).

METHODS

Patients who underwent CEA without concomitant procedures in the Vascular Quality Initiative database between 2003 and 2018 were included. Surgeons' practice patterns were defined on the basis of the distribution of completion imaging use among annual CEA cases per surgeon. Multivariable and Cox proportional hazards models were used to study the association between different practice patterns of completion imaging and perioperative and 1-year outcomes after CEA.

RESULTS

Of 98,055 CEA cases, 26,716 (27.3%) were performed with completion imaging. Compared with cases in which completion imaging was not performed, completion imaging was associated with increased rates of immediate re-exploration (3.5% vs 0.9%; odds ratio [OR], 3.84; 95% confidence interval [CI], 2.74-5.38; P < .001), overall return to the operating room (RTOR; 1.6% vs 1.2%; OR, 1.24; 95% CI, 1.08-1.42; P < .01), and longer operative time (median [interquartile range], 105 minutes [82-132] vs 119 minutes [92-148]; P < .001). Of 1920 surgeons in our cohort, 45% never performed completion imaging, whereas 26% rarely performed completion imaging (for ≤20% of annual CEA cases), 9.5% performed it selectively (21%-79% of annual CEAs), and 19.6% used completion imaging routinely (≥80% of annual CEAs). Rarely performing completion imaging had higher rates of immediate re-exploration (6.5% vs 0.9%; OR, 7.2; 95% CI, 5.7-9.2; P < .001), in-hospital stroke (4.0% vs 1.1%; adjusted OR [aOR], 3.4; 95% CI, 2.6-4.6; P < .001), RTOR for bleeding (1.9% vs 0.9%; aOR, 2.1; 95% CI, 1.5-2.9; P < .001), and neurologic events (1.5% vs 0.4%; aOR, 3.6; 95% CI, 2.2-5.9; P < .001) compared with not performing completion imaging. It was also associated with increased stroke/death and repeated revascularization at 30 days and significant restenosis at 1 year. On the other hand, performance of selective and routine completion imaging was associated with increased immediate re-exploration (selective: aOR, 3.2 [95% CI, 1.9-5.5; P < .001]; routine: aOR, 3.7 [95% CI, 2.5-5.6; P < .001]) without any increase in in-hospital, 30-day, and 1-year adverse outcomes compared with cases performed without completion imaging.

CONCLUSIONS

The performance of selective or routine completion imaging during CEA is safe and is not associated with increased adverse events compared with not using intraoperative completion imaging. However, rarely performing completion imaging is associated with a significant increase in the odds of perioperative stroke/death and RTOR, possibly because of unnecessary re-exploration for minor defects. The operator's experience and establishing a criterion for fixing residual defects are important to avoid unnecessary re-exploration.