The importance of internal carotid artery occlusion tolerance test in carotid endarterectomy under locoregional anesthesia

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.

One-year experience in carotid endarterectomy combining general anaesthesia with preserved consciousness and sequential carotid cross-clamping

Background and aim of the work: We report 1-year single-centre experience in carotid endarterectomy (CEA) combining general anaesthesia with preserved consciousness (GAPC) and standardized carotid sequential cross-clamping, for our protocol effectiveness evaluation in reduction of perioperative stroke, death or cardiologic complications. Methods: We considered all patients who underwent CEA in 2016. All patients underwent superficial cervical plexus block and GAPC with Remifentanil. The surgical technique consisted of common carotid artery (CCA) cross-clamping, carotid bifurcation isolation, external (ECA) and internal carotid artery (ICA) cross-clamping. After CCA cross-clamping, we performed a neurological tolerance test (NTT); this allowed selective shunting only for positive NTT. Primary end-points were: transient ischemic attack (TIA)/stroke, myocardial infarction, death in perioperative period. Secondary end-points were: carotid shunting, peripheral cranial nerves injuries (PCNI), GAPC intolerance, other complications, reintervention in perioperative period, length of hospital stay. Results: 104 consecutive patients underwent CEA with this protocol in the considered period. Twenty-seven (25.9%) patients were symptomatic. Mean clamping time was 48±13.5 minutes. Five cases (4.8%) requested internal carotid artery shunting. No TIA/stroke, myocardial infarction or death were recorded in the perioperative period. PCNI were observed in 19 cases (18.2%) in the immediate post-operative period; 16 of them (84.2%) showed complete or partial resolution at discharge. Only one patient (0.9%) showed GAPC intolerance. No other complication occurred. Three patients (2.9%) underwent reintervention for neck haematoma drainage. Mean hospital stay were 3±0.9 days. Conclusions: GAPC associated with sequential carotid cross-clamping appeared to be safe and effective in prevention of major neurological and cardiologic complications during CEA. (www.actabiomedica.it)