Short-term outcomes after selective shunt during carotid endarterectomy: a propensity score matching analysis

INTRODUCTION AND OBJECTIVES

Carotid cross-clamping during carotid endarterectomy might lead to intraoperative neurologic deficits, increasing stroke/death risk. If deficits are detected, carotid shunting has been recommended to reduce the risk of stroke. However, shunting may sustain a specific chance of embolic events and subsequently incurring harm. Current evidence is still questionable regarding its clear benefit. The aim is to determine whether a policy of selective shunt impacts the complication rate following an endarterectomy.

MATERIAL AND METHODS

From January 2013 to May 2021, all patients undergoing carotid endarterectomy under regional anesthesia with intraoperative neurologic alteration were retrieved. Patients submitted to selective shunt were compared to a non-shunt group. A 1:1 propensity score matching (PSM) was performed. Differences between the groups and clinical outcomes were calculated, resorting to univariate analysis.

RESULTS

Ninety-eight patients were selected, from which 23 were operated on using a shunt. After PSM, 22 non-shunt patients were compared to 22 matched shunted patients. Concerning demographics and comorbidities, both groups were comparable to pre and post-PSM, except for chronic heart failure, which was more prevalent in shunted patients (26.1%, P=0.036) in pre-PSM analysis. Regarding 30-day stroke and score Clavien-Dindo ≥2, no significant association was found (P=0.730, P=0.635 and P=0.942, P=0.472, correspondingly, for pre and post-PSM).

CONCLUSIONS

In this cohort, resorting to shunting did not demonstrate an advantage regarding 30-day stroke or a Clavien-Dindo ≥ 2 rates. Nevertheless, additional more extensive studies are mandatory to achieve precise results concerning the accurate utility of carotid shunting in this subset of patients under regional anesthesia.

Results of carotid endarterectomy with the use of temporary shunts with reduced retrograde pressure in the internal carotid artery - analysis of the multicenter Russian register

Aim

The aim of the study was to assess the role of a temporary carotid shunt in patients undergoing carotid endarterectomy.

Materials and methods

This was a retrospective, multicentric (n = 159) study carried out between January 2005 and October 2020. The study included 3114 patients undergoing carotid endarterectomy who had a reduced retrograde internal carotid artery pressure (<60% of systolic blood pressure). A temporary carotid shunt was used in 1328 patients and 1786 patients underwent carotid endarterectomy without a shunt.

Results

The in-hospital outcomes were comparable in terms of the incidence of deaths, myocardial infarctions, and stroke between the two groups. However, asymptomatic strokes (confirmed on computed tomography) occurred more frequently in the group where the temporary shunt was used (34 (2.5%) vs. 10 (0.55%), p < 0.0001). The composite endpoints of adverse events were also higher in the group where a temporary shunt was used (44 (3.3%) vs. 28 (1.5%), p = 0.002). The risk of symptomatic stroke (both fatal and non-fatal) was higher in the group where a temporary shunt was not used, though this was statistically not significant. Logistic regression analysis identified diabetes mellitus and stenosis (81-90%) of the contralateral internal carotid artery to be important predictors for stroke.

Conclusion

Temporary carotid shunts during carotid endarterectomy were associated with increased rates of asymptomatic stroke. There were no statistically significant differences in the incidence of non-fatal or fatal stroke, myocardial infarction, and mortality.

Update in Carotid Disease

This review of the literature analyzes publications over the past five years on various problems associated with carotid endarterectomy: 1. Is the eversion or classical technique of surgery with plastic repair of the reconstruction area with a patch more effective? 2. Carotid endarterectomy or carotid angioplasty with stenting is more optimal? 3. When should brain revascularization be performed after the development of ischemic stroke? 4. Should a temporary shunt be used to protect the brain during carotid endarterectomy? 5. How to prevent and treat different types of intraoperative ischemic strokes? 6. What tactics of treatment of patients with combined lesions of the carotid and coronary arteries is more effective? 7. What are the causes and methods of elimination of restenosis of the internal carotid artery known? 8. Is carotid endarterectomy safe in old age?

The value of transcranial Doppler monitoring of cerebral blood flow changes during carotid endarterectomy performed under regional anesthesia - A case series

Recent evidence suggests no difference between patient outcomes when carotid endarterectomies (CEAs) are performed under general or regional anesthesia. However, for detecting the need for a shunt, general anesthesia has the drawback of monitoring needs in the intraoperative setting. In the present study, we attempted to perform intraoperative transcranial Doppler (TCD) monitoring for CEAs performed under intermediate plexus block to describe cerebral hemodynamic changes during different phases of the procedure.

Patients and methods

Patients with unilateral hemodynamically significant carotid stenosis scheduled for elective CEAs were included. Ultrasound-guided intermediate plexus block was used for regional anesthesia. TCD monitoring of the middle cerebral artery mean blood flow velocity (MCAV) was performed throughout the procedure. MCAVs were offline analyzed during different phases of CEA: (1) resting state, before regional block, (2) after block, before incision, (3) before cross-clamp, (4) after cross-clamp, (5) 5 min after cross-clamp, (6) 10 min after cross-clamp, (7) after declamping, and (8) during the postoperative period (4-6 h).

Results

Shunt insertion based on the deterioration of neurological symptoms after cross-clamping was necessary for 11/66 patients (16.6%). In these symptomatic patients, the ipsilateral percent decrease of the MCAV was more than 70% in 8 out of 11 cases (72.7%). In asymptomatic patients, without shunt insertion, the average decrease of MCAV was less than 50%.

Conclusions

Neurological symptoms referring to cerebral ischemia may be superior to TCD monitoring of cerebral blood flow for detecting the necessity of a shunt. Regional anesthesia enables reliable, symptom-based monitoring of CEAs.

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.

Red blood cell distribution width is associated with hypoperfusion in carotid endarterectomy under regional anesthesia

BACKGROUND

A subset of patients submitted to carotid endarterectomy under regional anesthesia develop intraoperative neurologic deficit during carotid artery crossclamping related to critical cerebral perfusion, which may be owing to low flow or embolic phenomena. This subgroup is deemed prone to worse outcomes, which highlights its clinical relevance. The main aim of this study was to identify clinical and hematological predictors for intraoperative neurologic deficit. The secondary aim was to evaluate the perioperative prognostic value of postcarotid artery crossclamping manifestations of cerebral ischemia.

METHODS

Between January 2012 to January 2020, patients submitted to carotid endarterectomy under regional anesthesia in a tertiary referral center who presented intraoperative neurologic deficit were prospectively and consecutively included. This group constituted 8% of the total carotid endarterectomy performed in the center during this timeframe. The control group of patients was the subsequent patient submitted to carotid endarterectomy without intraoperative neurologic deficit in a 1:1 ratio. Blood samples were collected before surgery (<2 weeks). Propensity score matching was used to identify well-matched pairs of patients.

RESULTS

A total of 180 patients were included, with 90 (50% of the cohort and 8% of total carotid endarterectomies) presenting intraoperative neurologic deficit associated to clamping. Mean age was 71.4 ± 9.27 years in the study group and 68.8 ± 8.36 years in the control group. The clinical variables presenting significance after multivariate analysis include: age (adjusted odds ratio: 1.04, 5-95% confidence interval, [1.003-1.078]; P = .034), obesity (adjusted odds ratio: 3.537 [1.445-8.658]; P = .006), lower ipsilateral carotid stenosis grade (adjusted odds ratio: 0.725 [0.525-0.997]; P = .049), and higher contralateral carotid stenosis grade (adjusted odds ratio: 1.266 [1.057-1.516]; P = .010). Red cell distribution width coefficient of variation demonstrated statistical significance in predicting intraoperative neurologic deficit with an adjusted odds ratio of 1.394 (1.076-1.805); P = .012. The 30-day stroke rate was significantly higher in the intraoperative neurologic deficit group, with an adjusted odds ratio of 5.13 (5-95% confidence interval [1.058-24.87]; P = .042) after propensity score matching. Postoperative complications (Clavien-Dindo ≥2) were also associated with intraoperative neurologic deficit (after propensity score matching adjusted odds ratio of 2.748 [5-95% confidence interval, 0.976-7.741]; P = .051).

CONCLUSION

In this study, increased red cell distribution width coefficient of variation demonstrated value to predict intraoperative neurologic deficit. Additionally, age, obesity, a lower degree of ipsilateral carotid stenosis, and a higher degree of contralateral carotid stenosis also demonstrated ability to predict intraoperative neurologic deficit. Moreover, intraoperative neurologic deficit was an independent risk factor for 30-day stroke and postoperative complications Clavien-Dindo ≥2.

Impact of intraoperative neurologic deficits in carotid endarterectomy under regional anesthesia

OBJECTIVE

Patients undergoing carotid endarterectomy (CEA) may experiment neurologic deficits during the carotid cross-clamping due to secondary cerebral hypoperfusion. An associated risk of postoperative stroke incidence is also well established. This work aimed to assess the postoperative adverse events related to neurologic deficits in the awake test after clamping and to determine its predictive factors. Methods. From January 2012 to January 2018, 79 patients from a referral hospital that underwent CEA with regional anesthesia for carotid stenosis and manifested neurologic deficits were gathered. Consecutively selected controls (n = 85) were submitted to the same procedure without developing neurological changes. Postoperative complications such as stroke, myocardial infarction, all-cause death, and Clavien-Dindo classification were assessed 30 days after the procedure. Univariate and binary logistic regressions were performed for data assessment. Results. Patients with clamping associated neurologic deficits were significantly more obese than the control group (aOR = 9.30; 95% CI: 2.57-33.69; p = .01). Lower degree of ipsilateral stenosis and higher degree of contralateral stenosis were independently related to clamping intolerance (aOR = 0.70; 95% CI: 0.49-0.99; p = .047 and aOR = 1.30; 95% CI: 1.06-1.50; p = .009, respectively). Neurologic deficits were a main 30-day stroke predictor (aOR = 4.30; 95% CI: 1.10-16.71; p = .035). Conclusions. Neurologic deficits during carotid clamping are a predictor of perioperative stroke. Body mass index > 30 kg/m², a lower degree of ipsilateral stenosis, and a higher degree of contralateral stenosis are independent predictors of neurologic deficits and, therefore, might play a role in the prevention of procedure-related stroke.