Carotid Sinus Nerve Blockade to Reduce Blood Pressure Instability Following Carotid Endarterectomy: A Systematic Review and Meta-analysis

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.

Evaluation of the effect of carotid sinus blockade on hemodynamic stability in carotid surgery: A retrospective study

This study assesses the effect of carotid sinus blockade applied with a local anesthetic on hemodynamic parameters during carotid endarterectomy (CEA) operations performed under general anesthesia. The medical records of patients who underwent CEA under general anesthesia between January 2020 and December 2022, were retrospectively reviewed. It was recorded whether the patients received carotid sinus block with 2 mL of 2% prilocaine. Intraoperative and 48-hour postoperative hemodynamic data were examined in the patients included in the study. A total of 129 patients were evaluated in the study, with 70 patients who received carotid sinus blockade (Group I) and 59 patients who did not receive blockade (Group II) during CEA. The comparison of heart rate variability immediately before clamping, immediately after clamping, and at 5, 10, and 20 minutes post-clamping indicated a significantly greater reduction in Group II compared to Group I (P < .05). In the postoperative period, the total dose of glyceryl trinitrate administered was 40.8 ± 31.9 mg in Group I and 53 ± 17.2 mg in Group II, showing a statistically significant difference (P = .001). Additionally, blood pressure measurements during this period were significantly higher in Group II than in Group I (P < .05). While the application of a local anesthetic during CEA appears to provide better intraoperative heart rate and postoperative blood pressure control, attributing these results solely to local anesthesia may not be entirely accurate. Hemodynamic instability observed during and after CEA is influenced by various factors.

Nasal Intubation is not Associated with "Smoother" Emergence from General Anesthesia for Carotid Endarterectomy: A Case-Cohort Study

BACKGROUND

Postoperative hematoma after carotid endarterectomy (CEA) is a devastating complication and may be more likely in patients with uncontrolled hypertension and coughing on emergence from anesthesia. We sought to determine if intubation with a nasal endotracheal tube (ETT)-instead of an oral ETT-is associated with "smoother" (i.e., less hemodynamic instability) emergence from general anesthesia for CEA.

METHODS

Patients receiving CEA between December 2015 and September 2021 at a single tertiary academic medical center were included. We examined the electronic anesthesia records for 323 patients who underwent CEA during the 6-year study period and recorded consecutive systolic blood pressure (SBP) values during the 10 minutes before extubation as a surrogate for "smoothness" of the emergence.

RESULTS

Intubation with a nasal ETT, when compared with intubation with an oral ETT, was not associated with any difference in maximum, minimum, average, median, or standard deviation of serial SBP values in the 10 minutes before extubation. The average SBP on emergence for patients with an oral ETT was 141 mm Hg and with a nasal ETT was 144 mm Hg (P = 0.562). The maximum SBP for patients with oral and nasal ETTs were 170 mm Hg and 174 mm Hg, respectively (P = 0.491). There were also no differences in the qualitative "smoothness" of emergence or in the percentage of patients who required an intravenous dose of 1 or more antihypertensive medications. The incidence of postoperative complications was similar between the 2 groups.

CONCLUSIONS

When SBP is used as a surrogate for smoothness of emergence from general anesthesia for CEA, intubation with a nasal ETT was not associated with better hemodynamic stability compared to intubation with an oral ETT.

Redefining postoperative hypertension management in carotid surgery: a comprehensive analysis of blood pressure homeostasis and hyperperfusion syndrome in unilateral vs. bilateral carotid surgeries and implications for clinical practice

Background

This study evaluates the implications of blood pressure homeostasis in bilateral vs. unilateral carotid surgeries, focusing on the incidence of postoperative hypertension, hyperperfusion syndrome, and stroke as primary outcomes. It further delves into the secondary outcomes encompassing major adverse cardiovascular events and all-cause mortality.

Methods

Spanning two decades (2002-2023), this comprehensive retrospective research encompasses 15,369 carotid referrals, out of which 1,230 underwent carotid interventions. A subset of 690 patients received open carotid procedures, with a 10-year follow-up, comprising 599 unilateral and 91 bilateral surgeries. The Society for Vascular Surgery Carotid Reporting Standards underpin our methodological approach for data collection. Both univariate and multivariate analyses were utilized to identify factors associated with postoperative hypertension using the Statistical Package for the Social Sciences (SPSS) Version 22 (SPSS®, IBM® Corp., Armonk, N.Y., USA).

Results

A marked acute elevation in blood pressure was observed in patients undergoing both unilateral and bilateral carotid surgeries (p < 0.001). Smoking (OR: 1.183, p = 0.007), hyperfibrinogenemia (OR: 0.834, p = 0.004), emergency admission (OR: 1.192, p = 0.005), severe ipsilateral carotid stenosis (OR: 1.501, p = 0.022), and prior ipsilateral interventions (OR: 1.722, p = 0.003) emerged as significant factors that correlates with postoperative hypertension in unilateral surgeries. Conversely, in bilateral procedures, gender, emergency admissions (p = 0.012), and plaque morphology (p = 0.035) significantly influenced postoperative hypertension. Notably, 2.2% of bilateral surgery patients developed hyperperfusion syndrome, culminating in hemorrhagic stroke within 30 days. Intriguingly, postoperative stage II hypertension was identified as an independent predictor of neurological deficits post-secondary procedure in bilateral CEA cases (p = 0.004), attributable to hyperperfusion syndrome. However, it did not independently predict myocardial infarction or mortality outcomes. The overall 30-day stroke rate stood at 0.90%. Lowest incidence of post operative hypertension or any complications were observed in eversion carotid endartrertomy.

Conclusion

The study identifies postoperative hypertension as a crucial independent predictor of perioperative stroke following bilateral carotid surgery. Moreover, the study elucidates the significant impact of bilateral CEA on the development of post-operative hyperperfusion syndrome or stroke, as compared to unilateral CEA. Currently almost 90% of our carotid practice is eversion carotid endartrerectomy.

The Impact of Unilateral and Bilateral Eversion Carotid Endarterectomy on Postoperative Hemodynamic Parameters

Background:

Carotid endarterectomy (CEA) is an effective and safe treatment of stenosed carotid arteries, and is a preventive operation with well-defined indications. It is associated with a loss of the baroreceptor reflex and postoperatively increased hemodynamic parameters.

Objective:

The aim of the study was to confirm the sensitivity of baroreceptors and the impact on arterial pressure and heart rate in unilateral and bilateral eversion carotid endarterectomies.

Methods:

A retrospective study was conducted with 30 patients treated with E-CEA in local anesthesia at the Clinic for cardiovascular surgery from December 2019 to May 2021, due to stenosis of the carotid arteries. Patients were divided into two groups: 15 patients in group A (patients with unilateral E-CEA; 15 patients in group B: patients with bilateral E-CEA).

Results:

Out of the total of 30 patients included in the research, 15 patients in groups A and B respectively, there were no statistically significant differences in regards to gender (p= 0,245) and preoperative risk factors: smoking (p=0,449); hypertension (p=0,388); diabetes (p= 0,714); hyperlipidemia (p=0.388), coronary disease (p=0.461) and symptomatic stenosis of the carotid arteries (p=0.449). Noted were the statistically significant differences in values of systolic and diastolic pressure on the 3rd postoperative days in patients with bilateral E-CEA (p=0,001; p=0,001), a statistically significant difference in the heart rate was not found in the analyzed groups in the postoperative period (p=0,225; p=0,994).

Conclusion:

This study identified statistically significant differences in values of systolic and diastolic pressure in the early postoperative period. In his period, early detection and correction of these hemodynamic disorders are needed.

Laser speckle contrast imaging of forehead cutaneous blood flow during carotid endarterectomy as a potential non-invasive method for surrogate monitoring of cerebral perfusion

Monitoring cerebral perfusion is important for goal-directed anesthesia. Taking advantage of the supply of the supraorbital region and Glabella from the internal carotid artery (ICA), we evaluated changes in cutaneous blood flow using laser speckle contrast imagining (LSCI) as a potential method for indirect real-time monitoring of cerebral perfusion. Nine patients (8 men, mean age 70 years) underwent eversion carotid endarterectomy under local anesthesia. Cutaneous blood flow of the forehead was monitored using LSCI. During clamping of the common carotid artery (CCA), ipsilateral supraorbital region and Glabellas cutaneous blood flow dropped from 334 ± 135 to 221 ± 109 AU (p = 0.023) (AU: arbitrary flux units) and from 384 ± 151 to 276 ± 107 AU (p = 0.023), respectively, whilst the contralateral supraorbital region cutaneous blood flow remained unchanged. The supraorbital cutaneous blood flow did not change significantly following reperfusion of the external carotid artery (ECA) (221 ± 109 to 281 ± 154 AU; p = 0.175) and ICA (281 ± 154 to 310 ± 184 AU; p = 01). A comparable trend for Glabella followed ECA (276 ± 107 to 342 ± 170 AU; p = 0.404) and ICA (342 ± 170 to 352 ± 191 AU; p = 01) reperfusion. In patients undergoing carotid endarterectomy under local anesthesia, LSCI of the supraorbital and Glabella regions reflected clamping of the CCA but did not distinguish reperfusion of the ICA from that of the ECA.

Surgical Technique for Carotid Endarterectomy: Current Methods and Problems

Over the last 60 years, many reports have investigated carotid endarterectomy (CEA) and techniques have thus changed and improved. In this paper, we review the recent literature regarding operational maneuvers for CEA and discuss future problems for CEA. Longitudinal skin incision is common, but the transverse incision has been reported to offer minimal invasiveness and better cosmetic effects for CEA. Most surgeons currently use microscopy for dissection of the artery and plaque. Although no monitoring technique during CEA has been proven superior, multiple monitors offer better sensitivity for predicting postoperative neurological deficit. To date, data are lacking regarding whether routine shunt or selective shunt is better. Individual surgeons thus need to select the method with which they are more comfortable. Many surgical techniques have been reported to obtain distal control of the internal carotid artery in patients with high cervical carotid bifurcation or high plaque, and minimally invasive techniques should be considered. Multiple studies have shown that patch angioplasty reduces the risks of stroke and restenosis compared with primary closure, but few surgeons in Japan have been performing patch angioplasty. Most surgeons thus experience only a small volume of CEAs in Japan, so training programs and development of in vivo training models are important.

Carotid Sinus Nerve: A Comprehensive Review of Its Anatomy, Variations, Pathology, and Clinical Applications

The carotid sinus nerve branches off the glossopharyngeal nerve just after its appearance from the jugular foramen, descends along the internal carotid artery, and enters the carotid sinus. There have been many studies of the pathway and the course of the carotid sinus nerve and its communications with surrounding nerves. The intercommunication is exceedingly complicated. Acknowledgment of its anatomic diversity can be important in specific operations dealing with this area. Herein we review the anatomy, variations, pathology, and clinical applications of the carotid sinus nerve.

Surgical Pitfalls in Carotid Endarterectomy: A New Step-By-Step Approach

Carotid endarterectomy (CEA) is a surgical intervention that may prevent stroke in asymptomatic and symptomatic patients. Our aim was to examine the microsurgical anatomy of carotid artery and other related neurovascular structures to summarize the CEA that is currently applied in ideal conditions. The upper necks of 2 adult cadavers (4 sides) were dissected using ×3 to ×40 magnification. The common carotid artery, external carotid artery (ECA), and internal carotid artery were exposed and examined. The surgical steps of CEA were described using 3-D cadaveric photos and computed tomography angiographic pictures obtained with help of OsiriX imaging software program. Segregating certain neurovascular and muscular structures in the course of CEA significantly increased the exposure. The division of facial vein allowed for internal jugular vein to be mobilized more laterally and dividing the posterior belly of digastric muscle resulted in an additional dorsal exposure of almost 2 cm. Isolating the ansa cervicalis that pulls hypoglossal nerve inferiorly allowed hypoglossal nerve to be released safely medially. The locations of the ECA branches alter depending on their anatomical variations. The hypoglossal nerve, glossopharyngeal nerve, and accessory nerve pierce the fascia of the upper part of the carotid sheath and they are vulnerable to injury because of their distinct courses along the surgical route. Surgical exposure in CEA requires meticulous dissection and detailed knowledge of microsurgical anatomy of the neck region to avoid neurovascular injuries and to determine the necessary surgical maneuvers in cases with neurovascular variations.

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).

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.

[Clinical relevance of cardiopulmonary reflexes in anesthesiology]

The baroreflex, chemoreflex, pulmonary reflexes, Bezold-Jarisch and Bainbridge reflexes and their interaction with local mechanisms, are a demonstration of the richness of cardiovascular responses that occur in human beings. As well as these, the anesthesiologist must contend with other variables that interact by attenuating or accentuating cardiopulmonary reflexes such as, anesthetic drugs, surgical manipulation, and patient positioning. In the present article we review these reflexes and their clinical relevance in anesthesiology.

The need for treatment of hemodynamic instability following carotid endarterectomy is associated with increased perioperative and 1-year morbidity and mortality

OBJECTIVE

The objective of this study was to evaluate the outcomes of patients after carotid endarterectomy (CEA) who developed postoperative hypertension or hypotension requiring the administration of intravenous vasoactive medication (IVMED).

METHODS

We examined consecutive, primary elective CEA performed by 128 surgeons within the Vascular Study Group of New England (VSGNE) database (2003-2010) and compared outcomes of patients who required postoperative IVMED to treat hyper- or hypotension with those who did not. Outcomes included perioperative death, stroke, myocardial infarction (MI), congestive heart failure (CHF), hospital length of stay, and 1-year stroke or death. Propensity score matching was performed to facilitate risk-adjusted comparisons. Multivariable regression models were used to compare the association between IVMED and outcomes in unmatched and matched samples. Factors associated with use of IVMED in postoperative hypertension and hypotension were evaluated, and predictive performance of multivariable models was examined using receiver operating characteristic (ROC) curves.

RESULTS

Of 7677 elective CEAs identified, 23% received IVMED for treatment of either postoperative hypertension (11%) or hypotension (12%). Preoperative neurological symptomatic status (20%) was similar across cohorts. In the crude sample, the use of IVMED to treat postoperative hypertension was associated with increased 30-day mortality (0.7% vs 0.1%; P < .001), stroke (1.9% vs 1%; P = .018), MI (2.4% vs 0.5%; P < .001), and CHF (1.9% vs 0.5%; P < .001). The use of IVMED to treat postoperative hypotension was also associated with increased perioperative mortality (0.8% vs 0.1%; P < .001), stroke (3.2% vs 1.0%; P < .001), MI (2.7% vs 0.5%; P < .001), and CHF (1.7% vs 0.5%; P < .001), as well as 1-year death (5.1% vs 2.9%; P < .001) or stroke (4.2% vs 2.1%; P < .001). Hospital length of stay was significantly longer among patients who needed IVMED for postoperative hypertension (2.8 ± 4.7 days vs 1.7 ± 5.5 days; P < .001) and hypotension (2.8 ± 5.9 days vs 1.7 ± 5.5 days; P < .001). In multivariable analysis, IVMED for postoperative hypertension was associated with increased MI, stroke, or death (odds ratio, 2.6; 95% confidence interval [CI], 1.6-4.1; P < .001). Similarly, IVMED for postoperative hypotension was associated with increased MI, stroke, or death (odds ratio, 3.2; 95% CI, 2.1-5.0; P < .001), as well as increased 1-year stroke or death (hazard ratio, 1.6; 95% CI, 1.2-2.2; P = .003). Smoking, coronary artery disease, and clopidogrel (ROC, 0.59) were associated with postoperative hypertension requiring IVMED, whereas conventional endarterectomy and general anesthesia were associated with postoperative hypotension requiring IVMED (ROC, 0.58). The unitization of IVMED varied between 11% and 38% across VSGNE, and center effect did not affect outcomes.

CONCLUSIONS

Postoperative hypertension requiring IVMED after CEA is associated with increased perioperative mortality, stroke, and cardiac complications, whereas significant postoperative hypotension is associated with increased perioperative mortality, cardiac, or stroke complications, as well as increased 1-year death or stroke following CEA. The utilization of IVMED varied across centers and, as such, further investigation into this practice needs to occur in order to improve outcomes of these at-risk patients.