The effects of carotid sinus nerve blockade on hemodynamic stability after carotid endarterectomy

Intraoperative intracarotid injection of anesthetics for postoperative blood pressure lability management in carotid endarterectomy: A meta-analysis of randomized controlled trials

Carotid endarterectomy (CEA) is commonly performed to prevent ischemic stroke in patients with significant carotid stenosis but is linked to perioperative blood pressure instability. Intracarotid lidocaine injection has been proposed to improve postoperative hemodynamic stability, but evidence of its efficacy and safety remains mixed. We conducted a meta-analysis of randomized controlled trials (RCTs) assessing the intraoperative intracarotid injection of local anesthetics in CEA, following PRISMA guidelines. Primary outcomes included postoperative blood pressure variability, adverse cardiovascular events, and overall complication rates. Secondary outcomes assessed mortality and incidence of restenosis in the short and long term. Seven RCTs comprising 652 patients were included, with lidocaine as the most commonly used anesthetic. No statistically significant differences were found in postoperative hypotension (OR 1.31, 95% CI 0.62-2.76), hypertension (OR 1.03, 95% CI 0.5-2.15), or mean blood pressure (MD 4.12 mmHg, 95% CI -3.35-11.60). Additionally, postoperative rates of arrhythmias (OR 1.22, 95% CI 0.7-2.12), myocardial infarction (OR 2.03, 95% CI 0.08-54.6), overall complications (OR 1.41, 95% CI 0.74-2.66), and cerebrovascular accidents (OR 2.55, 95% CI 0.61-10.57) did not differ significantly between groups. Intraoperative intracarotid injection of local anesthetic shows no significant benefit for stabilizing postoperative blood pressure in CEA patients. This meta-analysis did not support the hypothesized reduction in carotid sinus sensitivity. However, the small sample size increases the risk of type II error, and long-term outcomes, especially restenosis rates, require further investigation.

Case report: Cardiac arrest during carotid body tumor resection indicating carotid sinus hypersensitivity

Background

Carotid body tumor surgery is associated with various complications. However, intraoperative cardiac arrest is very rare and no more than 10 cases have been reported.

Case description

A 58-year-old woman diagnosed with bilateral carotid body tumors underwent right carotid body tumor surgery. Sudden cardiac arrest occurred during the resection and was attributed to carotid sinus hypersensitivity. The patient recovered after prompt treatment and the tumor was removed completely with no complications.

Conclusion

Cardiac arrest attributed to carotid sinus hypersensitivity during carotid body tumor resection is very rare. Proper treatments can reverse intraoperative cardiac arrest. If carotid sinus hypersensitivity is detected preoperatively, prophylactic temporary pacemaker implantation may be appropriate.

Carotid Endarterectomy with Autoarterial Remodeling of Bifurcation of the Common Carotid Artery and Carotid Endarterectomy with Patch Closure: Comparison of Methods

BACKGROUND

The objectives of our research were to identify whether the new method of carotid endarterectomy (CEA) with autoarterial remodeling of bifurcation of the common carotid artery (ARBCCA) influences daily parameters of blood pressure and heart rate (HR) while monitoring them on a daily basis and to assess the efficacy of the suggested method.

MATERIALS AND METHODS

It is a prospective randomized comparative study. The first group (n = 100) included patients that underwent ARBCCA, the second group (n = 100) included patients that underwent "classic" CEA with xenopericardial patch closure. Diurnal Holter recording of blood pressure and (HR) was performed before and after the surgical treatment in both groups.

RESULTS

Surgical treatment in both groups leads to an increase of HR, arterial hypertension time index by systolic blood pressure, and arterial hypertension time index by diastolic arterial blood pressure. The damage of carotid artery bulb increases sympathetic innervation and causes dysregulation of the baroreceptor mechanism.

CONCLUSIONS

In our study, we did not reveal a significant difference in the incidence of postoperative hypertension and the dependence of HR on the choice of surgical technique. Thus, the proposed ARBCCA method does not lead to an increased risk of pre-existing arterial hypertension development. A significant difference is found out on the parameter of the clamping time of carotid arteries in favor to ARBCCA group. Another advantage of the suggested technique is the number of restenosis greater than 50% during the 2-year follow-up (4 [4%] cases (ARBCCA group) versus 12 [12%] cases ["classic" CEA], respectively, P = .037).

Ultrasound-guided superficial cervical plexus block under dexmedetomidine sedation versus general anesthesia for carotid endarterectomy: a retrospective pilot study

Background

Carotid endarterectomy (CEA) has been performed under regional and general anesthesia (GA). The general anesthesia versus local anesthesia for carotid surgery study compared the two techniques and concluded that there was no difference in perioperative outcomes. However, since this trial, new sedative agents have been introduced and devices that improve the delivery of regional anesthesia (RA) have been developed. The primary purpose of this pilot study was to compare intraoperative hemodynamic stability and postoperative outcomes between GA and ultrasound-guided superficial cervical plexus block (UGSCPB) under dexmedetomidine sedation for CEA.

Methods

Medical records from 43 adult patients who underwent CEA were retrospectively reviewed, including 16 in the GA group and 27 in the RA group. GA was induced with propofol and maintained with sevoflurane. The UGSCPB was performed with ropivacaine under dexmedetomidine sedation. We compared the intraoperative requirement for vasoactive drugs, postoperative complications, pain scores using the numerical rating scale, and the duration of hospital stay.

Results

There was no difference between groups in the use of intraoperative antihypertensive drugs. However, intraoperative inotropic and vasopressor agents were more frequently required in the GA group (p<0.0001). In the GA group, pain scores were significantly higher during the first 24 h after surgery (p<0.0001 between 0-6 h, p<0.004 between 6-12 h, and p<0.001 between 12-24 h). The duration of hospital stay was significantly more in the GA group (13.3±4.6 days in the GA group vs. 8.5±2.4 days in the RA group, p<0.001).

Conclusion

In this pilot study, intraoperative hemodynamic stability and postoperative outcomes were better in the RA compared to the GA group.

The Carotid Sinus Nerve-Structure, Function, and Clinical Implications

Interest has been renewed in the anatomy and physiology of the carotid sinus nerve (CSN) and its targets (carotid sinus and carotid body, CB), due to recent proposals of surgical procedures for a series of common pathologies, such as carotid sinus syndrome, hypertension, heart failure, and insulin resistance. The CSN originates from the glossopharyngeal nerve soon after its appearance from the jugular foramen. It shows frequent communications with the sympathetic trunk (usually at the level of the superior cervical ganglion) and the vagal nerve (main trunk, pharyngeal branches, or superior laryngeal nerve). It courses on the anterior aspect of the internal carotid artery to reach the carotid sinus, CB, and/or intercarotid plexus. In the carotid sinus, type I (dynamic) carotid baroreceptors have larger myelinated A-fibers; type II (tonic) baroreceptors show smaller A- and unmyelinated C-fibers. In the CB, afferent fibers are mainly stimulated by acetylcholine and ATP, released by type I cells. The neurons are located in the petrosal ganglion, and centripetal fibers project on to the solitary tract nucleus: chemosensory inputs to the commissural subnucleus, and baroreceptor inputs to the commissural, medial, dorsomedial, and dorsolateral subnuclei. The baroreceptor component of the CSN elicits sympatho-inhibition and the chemoreceptor component stimulates sympatho-activation. Thus, in refractory hypertension and heart failure (characterized by increased sympathetic activity), baroreceptor electrical stimulation, and CB removal have been proposed. Instead, denervation of the carotid sinus has been proposed for the "carotid sinus syndrome." Anat Rec, 302:575-587, 2019. © 2018 Wiley Periodicals, Inc.

Effect of Superficial Cervical Plexus Block on Baroreceptor Sensitivity in Patients Undergoing Carotid Endarterectomy

OBJECTIVES

Regional anesthesia for patients undergoing carotid endarterectomy is associated with improved intraoperative hemodynamic stability compared with general anesthesia. The authors hypothesized that the reported advantages might be related to attenuated ipsilateral baroreflex control of blood pressure, caused by chemical denervation of the carotid bulb baroreceptor nerve fibers.

DESIGN

A prospective cohort study.

SETTING

Single-center university hospital.

PARTICIPANTS

The study included 46 patients undergoing carotid endarterectomy using superficial cervical block.

INTERVENTIONS

A noninvasive computational periprocedural measurement of baroreceptor sensitivity was performed in all patients. Two groups were formed, depending on the patients' subjective response to surgical stimulation regarding the necessity of additional intraoperative local anesthesia (LA) administration on the carotid bulb. Group A (block alone) included 23 patients who required no additional anesthesia, and group B (block + LA) consisted of 23 patients who required additional anesthesia.

MEASUREMENTS AND MAIN RESULTS

Baroreceptor sensitivity showed no significant change after application of the block in both groups (group A: median [IQR], 5.19 [3.07-8.54] v 4.96 [3.1-9.07]; p = 0.20) (group B: median [IQR], 4.47 [3.36-8.09] v 4.53 [3.29-8.01]; p = 0.55). There was a significant decrease in baroreceptor sensitivity in group B after intraoperative LA administration (median [IQR], 4.53 [3.29-8.01] v 3.31 [2.26-7.31]; p = 0.04).

CONCLUSIONS

Standard superficial cervical plexus block did not impair local baroreceptor function, and, therefore, it was not related to improved cerebral perfusion in awake patients undergoing carotid endarterectomy. However, direct infiltration of the carotid bulb was associated with the expected attenuation of baroreflex sensitivity.

Intraoperative management of carotid endarterectomy

First reports on surgical treatment of cerebrovascular atherosclerosis date to the early 1950s. With advancements in surgical technique, carotid endarterectomy (CEA) has become the treatment of choice for patients with both symptomatic and asymptomatic severe carotid stenosis. Given the benefits that surgery offers beyond medical management, the number of CEA procedures continues to increase. The intraoperative management of patients undergoing CEA is challenging because of the combination of patient and surgical factors. This article explores and reviews the literature on anesthetic management and considerations of patients undergoing CEA.

Percutaneous injection of lidocaine within the carotid body area in carotid artery stenting: an "old-new" technique

Severe bradycardia is a common untoward effect during balloon angioplasty when performing carotid artery stenting. Therefore atropine injection even before dilatation and the presence of an anesthesiologist are advocated in all patients. In the surgical literature, injection of a local anesthetic agent into the carotid sinus before carotid endarterectomy was performed in an attempt to ameliorate perioperative hemodynamic instability. This study was undertaken to test the hypothesis that percutaneous infiltration of the carotid sinus with local anesthetic immediately before balloon dilatation reduces bradycardia and ameliorates the need for atropine injection or the presence of an anesthesiologist. Infiltration of the carotid sinus with 5 ml of 1% lidocaine, 3 min before dilatation, was performed in 30 consecutive patients. No one exhibited any significant rhythm change that required atropine injection. The anesthesiologist did not face any hemodynamic instability during the carotid artery stenting procedure.

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.

Effect of lignocaine injection in carotid sinus on baroreceptor sensitivity during carotid endarterectomy

OBJECTIVES

This study was undertaken to test the hypothesis that there is a neural basis for baroreceptor deterioration during carotid endarterectomy (CEA), by investigating intraoperative hemodynamic changes induced by intraluminal carotid stretch stimulation, before and after application of local anesthetic to the adventitial layer of the carotid sinus region.

METHODS

This was a prospective study of 20 patients undergoing elective CEA. During CEA, before removal of the atheroma, intraluminal stretch simulation of the carotid baroreceptors (rub test) was performed before and after injection of 1% lignocaine into adventitial tissue of the artery in the region of the carotid sinus. Continuous measurements of mean arterial blood pressure (MAP), electrocardiographic r-r intervals (R-R), heart rate, cardiac vagal tone, and carotid sinus baroreflex were recorded to determine alterations in baroreceptor function.

RESULTS

Rub test before injection of lignocaine was associated with a decrease in MAP and heart rate and an increase in R-R, cardiac vagal tone, and carotid baroreflex response, indicating a functioning baroreflex. After lignocaine injection and repetition of the rub test, no significant change was seen in MAP, heart rate, R-R, cardiac vagal tone, or carotid baroreflex response, indicating a nonfunctioning baroreflex. Comparing the peak responses to the rub test stimulus before and after lignocaine injection showed significant differences for all variables (P <.05), with carotid baroreflex response and heart rate being highly significant (P <.0005).

CONCLUSIONS

The baroreflex response to intraluminal stretch stimulation of the carotid sinus area is operational in patients undergoing CEA, and this response is abolished by infiltration of local anesthetic into the periadventitial tissue around the carotid sinus.

Preoperative assessment and management to prevent complications during high-risk vascular surgery

OBJECTIVE

Most patients requiring vascular surgical reconstruction are at high risk for major morbidity and mortality, with certain vascular procedures at particularly high risk for complications. Although numerous comorbid conditions are precisely the risk factors that determine outcome, we review particular factors for each surgery that may be optimized to alter outcome and minimize postoperative complications.

DESIGN

Literature review.

RESULTS

Certain aspects of care are common to all vascular surgery procedures, including thoracoabdominal aortic aneurysm repair, pararenal and ruptured abdominal aortic aneurysm repair, mesenteric and renal revascularization, and carotid endarterectomy. Some factors that are important include careful preoperative assessment and optimization of cardiac, pulmonary, and renal function and volume status. In addition, the use of experienced teams during and after the procedure, as well as clear and continuous communication between all surgical team members, may improve outcome. Particular attention to procedural details is also crucial to achieving excellent results.

CONCLUSIONS

Patients needing vascular surgery often possess management challenges that increase the risk of perioperative complications. Meticulous attention to details during all phases of care, including preoperative optimization as well as intraoperative procedural conduct and communication, helps achieve optimal results and thus minimize the risk of complications.

Carotid sinus nerve blockade during carotid surgery: a randomised controlled trial

OBJECTIVES

we investigated whether carotid sinus nerve infiltration with lignocaine reduced blood pressure lability during the first 24h following carotid endarterectomy (CEA).

DESIGN

prospective randomised double-blind controlled trial.

MATERIALS

eighty patients undergoing CEA for significant symptomatic stenosis of the internal carotid artery.

METHODS

after initial dissection, 5 ml of 1% lignocaine or normal saline placebo according to randomisation was infiltrated around the carotid sinus nerve. Blood pressure was measured by intra-arterial cannula during surgery and for four hours afterwards every 15 min, then manually, hourly for 18 h.

RESULTS

patients having excision of the carotid sinus nerve were grouped separately for analysis: 29 patients had lignocaine, 33 placebo and 17 excision (one early death with incomplete data was excluded). Mean systolic, diastolic and pulse pressures did not differ significantly between the three groups before carotid sinus nerve infiltration. After infiltration, those patients who had carotid sinus nerve excision, had significantly higher systolic [mean (SD)=155 (16)mmHg] and diastolic [75 (9)mmHg] pressures than those receiving LA [systolic=136 (15)mmHg, diastolic=65 (10)mmHg] or placebo [systolic=136 (19)mmHg, diastolic=65 (9)mmHg], (p<0.005 ANOVA). Nerve excision also resulted in wider variability of blood pressure as defined by the mean of individual standard deviations (systolic=25 mmHg, diastolic=13 mmHg) compared to LA (systolic=19 mmHg, diastolic=12 mmHg) or placebo (systolic=18 mmHg, diastolic=10 mmHg) (p<0.05 ANOVA). Normotensive patients had significantly lower mean diastolic pressures (p<0.001 ANOVA) and variability (p<0.05) if they received lignocaine although this did not influence pulse pressure.

CONCLUSIONS

lignocaine injection of the carotid sinus nerve has no benefit in those patients with existing treated hypertension and only marginal effects in normotensives. It is more important to preserve the carotid sinus nerve if possible.

Eversion technique increases the risk for post-carotid endarterectomy hypertension

OBJECTIVE

The incidence of postoperative hypertension (HTN) after eversion carotid endarterectomy (e-CEA) was compared with that after standard carotid endarterectomy (s-CEA).

METHODS

In a retrospective analysis from January 1998 to January 2000, 217 patients underwent 219 CEAs for symptomatic (68) or asymptomatic (151) high-grade (>80%) carotid artery stenosis by either standard (137) or eversion (82) techniques. The eversion technique involves an oblique transection of the internal carotid artery at the carotid bulb and a subsequent endarterectomy by everting the internal carotid artery over the atheromatous plaque. All procedures were done under general anesthesia, and somatosensory-evoked potentials were used for cerebral monitoring. Patients with s-CEA were compared with those with e-CEA for postoperative hemodynamic instability, carotid sinus nerve block, requirement for intravenous vasodilators or vasopressors, stroke, and death.

RESULTS

Patients who underwent e-CEA had a significantly (P <.005) increased postoperative blood pressure and required more frequent intravenous antihypertensive medication (24%), compared with patients having an s-CEA (6%). Furthermore, postoperative vasopressors were required after 10% of s-CEAs, but after none of the e-CEAs. No statistically significant difference was noted in the morbidity or mortality of patients after s-CEA and e-CEA.

CONCLUSION

e-CEA is a substantial risk factor for HTN in the immediate postoperative period, when compared with the s-CEA. This difference would be even more remarkable in the absence of antihypertensive medications in the e-CEA group and vasopressors in the s-CEA group. Therefore, particular attention should be focused on diagnosing and controlling postoperative HTN in patients after e-CEA.

The Hemodynamic Effects of Local Anesthetic Injection into the Carotid Body during Carotid Endarterectomy

Hemodynamic changes consisting of hypertension, hypotension, or bradycardia are commonly seen in patients undergoing carotid endarterectomy. It is a potentially serious clinical problem that may increase mortality rates or incidence of neurologic deficits. The frequency of hemodynamic alterations has been believed to be related to the proximity of the carotid sinus baroreceptor to the endarterectomized region. Consequently, intraoperative or postoperative injection of local anesthetics into the carotid body have been recommended to help offset this compensatory mechanism. However, its effectiveness has not been thoroughly studied. We examined this situation with a prospective, randomized, double-blind clinical study consisting of 99 patients. Xylocaine (short-acting anesthetic), bupivacaine (long-acting anesthetic), or saline (control) was injected into the carotid body intraoperatively. Intraoperative and postoperative hemodynamic changes were then closely monitored and evaluated. We were unable to detect a significant difference in hypotension, hypertension, or bradycardia either during or after surgery. Therefore, on the basis of this study, routine use of local anesthetic injection into the carotid body cannot be recommended.

Anesthesia for carotid endarterectomy

Patients presenting for carotid endarterectomy provide anesthesiologists with many challenges. These include optimization of cerebrovascular hemodynamics and oxygen balance, as well as minimizing myocardial risk. Fiscal pressures have encouraged the development of clinical pathways in many centers, with a remarkable trend towards decreased intensive care unit utilization and length of hospital stay. Anesthetic and surgical practices vary widely, but outcomes in these high-risk patients are usually excellent despite these differences. The potential for expanded indications for carotid endarterectomy and development of percutaneous treatment for carotid stenosis will provide neurovascular anesthesiologists with additional incentives to refine the anesthetic management of these patients.