Cost-Effectiveness of Two Decision Strategies for Shunt Use During Carotid Endarterectomy

Optimal cutoff value of carotid stump pressure for determining the need for a carotid shunt in carotid artery endarterectomy

OBJECTIVE

This study was conducted to identify the diagnostic value of carotid stump pressure for determining the need for a carotid artery shunt in patients undergoing carotid artery endarterectomy.

MATERIALS AND METHODS

Carotid stump pressure was prospectively measured in all carotid artery endarterectomies performed under local anesthesia between January 2020 and April 2022. The shunt was selectively used when neurological symptoms appeared after carotid cross-clamping. Carotid stump pressure was compared between patients who needed shunting and those who did not. Demographic and clinical characteristics, hematological and biochemical parameters, and carotid stump pressure of the patients with and without shunts were statistically compared. To determine the optimal cutoff value and diagnostic performance of carotid stump pressure for identifying the patients who need a shunt, receiver operating characteristic analysis was performed.

RESULTS

Overall, 102 patients (61 men and 41 women) who underwent carotid artery endarterectomy under local anesthesia were included, with an age range of 51-88 years. A carotid artery shunt was used in 16 (8 men and 8 women) patients. The carotid stump pressure values of the patients with a shunt were lower than those without a shunt (median (min-max): 42 (20-55) vs 51 (20-104), p < 0.0006). In the receiver operating characteristic curve analysis performed to determine the need for a shunt, the optimal cutoff value of carotid stump pressure was ≤48 mmHg, sensitivity was 93.8%, and specificity was 61.6% (area under the curve: 0.773, p < 0.0001).

CONCLUSION

Carotid stump pressure has sufficient diagnostic power to determine the need for a shunt, but it cannot be used alone in the clinical setting. Instead, it can be used in combination with other neurological monitoring methods.

Comparison of Methods for Monitoring Intra-operative Cerebral Perfusion in Patients Undergoing Carotid Endarterectomy with Selective Shunting: A Systematic Review and Network Meta-Analysis of Randomised Controlled Trials and Cohort Studies

OBJECTIVE

This study aimed to analyse the influence of different methods of monitoring cerebral perfusion (MCP) on stroke, death, and use of intraluminal shunt during carotid endarterectomy (CEA).

METHODS

A systematic review and network meta-analysis was conducted and registered in the PROSPERO registry (CRD42021246360). Medline, Embase, CENTRAL, and Web of Science were searched. Randomised controlled trials (RCTs) and cohort studies with > 50 participants that compared clinical outcomes for different MCP in patients undergoing CEA were included. Papers reporting one or a combination of two of the following MCPs were included in the analysis: awake testing (AT), near infrared spectroscopy (NIRS), electroencephalography (EEG), somatosensory evoked potential (SSEP), motor evoked potential (MEP), transcranial Doppler (TCD), and stump pressure (SP). A random effects network meta-analysis was performed using a binomial likelihood function with a specified logit link for peri-operative stroke or death and shunting as outcomes. Near infrared spectroscopy was excluded due to the lack of studies that could be used for statistical analysis.

RESULTS

Of 1 834 publications, 17 studies (15 cohort studies and two RCTs) including 21 538 participants were incorporated in the quantitative analysis. Electroencephalography was used in the largest number of participants (7 429 participants, six studies), while AT was used in the highest number of studies (10 studies). All monitoring modalities had worse outcomes with respect to stroke or death when compared with AT, with ORs ranging between 1.3 (95% credible interval [CrI] 0.2 - 10.9) for SSEP + MEP and 3.1 (CrI 0.3 - 35.0) for patients monitored with a combination of EEG and TCD. However, the wide CrI indicated that there is no statistically significant difference between the monitoring methods. Patients monitored with a combination of EEG and TCD had the lowest odds of being shunted, while SP had the highest odds of being shunted, also with no statistically significant difference.

CONCLUSION

There is a lack of high quality data on this topic in the literature. The present study showed no significant difference between monitoring methods investigated in the network meta-analysis.

[Effect of different shunt strategies on cerebral infarction after carotid endarterectomy]

OBJECTIVE

The key point of anesthesia management in carotid endarterectomy (CEA) is to maintain adequate cerebral perfusion during carotid artery occlusion. Placement of shunt is one of the common surgical methods. This study analyzed the effects of different shunt strategies on cerebral infarction after carotid endarterectomy.

METHODS

A total of 443 patients who underwent CEA under general anesthesia within 2 years were divided into imaging group (based on preoperative imaging data as the basis for shunt) and stump pressure group (based on intraoperative stump pressure as the basis for shunt). The preoperative demographic data, past medical history, degree of cervical vascular stenosis, blood pressure at each time point during the perioperative period, vascular blocking time, whether to place the shunt, postoperative hospital stay, cerebral infarction during hospitalization, and other adverse events were collected and compared between the two groups. On this basis, the preoperative and intraoperative conditions with significant differences were matched with propensity scores, and the influence of different shunt strategies on postoperative cerebral infarction was analyzed.

RESULTS

In the study, 268 patients in the imaging group and 175 patients in the stump pressure group underwent CEA under general anesthesia. There were statistically significant differences in basic conditions and blood pressure at each time point between the two groups. After matching the propensity scores, 105 patients in each of the two groups were matched. The basic conditions of the patients before surgery and the difference in blood pressure of the two groups at each time point were not statistically significant. There was no significant diffe-rence in the incidence of postoperative cerebral infarction between the two groups (1.9% vs. 1.0%, P>0.999). The intraoperative shunt rate in the imaging group was lower than that in the stump pressure group (0 vs. 22.9%, P < 0.001). The postoperative hospital stay in the imaging group was 8 (7, 8) days, which was longer than the stump pressure group 5 (4, 6) days (P < 0.001).

CONCLUSION

The rate of the shunt was lower according to preoperative imaging examination than that according to the residual pressure in our hospital. There is no significant difference in the incidence of cerebral infarction during the postoperative hospital stay. The effect of different shunt strategies on cerebral infarction needs further study.

[Effect of different shunt strategies on cerebral infarction after carotid endarterectomy]

OBJECTIVE

The key point of anesthesia management in carotid endarterectomy (CEA) is to maintain adequate cerebral perfusion during carotid artery occlusion. Placement of shunt is one of the common surgical methods. This study analyzed the effects of different shunt strategies on cerebral infarction after carotid endarterectomy.

METHODS

A total of 443 patients who underwent CEA under general anesthesia within 2 years were divided into imaging group (based on preoperative imaging data as the basis for shunt) and stump pressure group (based on intraoperative stump pressure as the basis for shunt). The preoperative demographic data, past medical history, degree of cervical vascular stenosis, blood pressure at each time point during the perioperative period, vascular blocking time, whether to place the shunt, postoperative hospital stay, cerebral infarction during hospitalization, and other adverse events were collected and compared between the two groups. On this basis, the preoperative and intraoperative conditions with significant differences were matched with propensity scores, and the influence of different shunt strategies on postoperative cerebral infarction was analyzed.

RESULTS

In the study, 268 patients in the imaging group and 175 patients in the stump pressure group underwent CEA under general anesthesia. There were statistically significant differences in basic conditions and blood pressure at each time point between the two groups. After matching the propensity scores, 105 patients in each of the two groups were matched. The basic conditions of the patients before surgery and the difference in blood pressure of the two groups at each time point were not statistically significant. There was no significant diffe-rence in the incidence of postoperative cerebral infarction between the two groups (1.9% vs. 1.0%, P>0.999). The intraoperative shunt rate in the imaging group was lower than that in the stump pressure group (0 vs. 22.9%, P < 0.001). The postoperative hospital stay in the imaging group was 8 (7, 8) days, which was longer than the stump pressure group 5 (4, 6) days (P < 0.001).

CONCLUSION

The rate of the shunt was lower according to preoperative imaging examination than that according to the residual pressure in our hospital. There is no significant difference in the incidence of cerebral infarction during the postoperative hospital stay. The effect of different shunt strategies on cerebral infarction needs further study.

The Role of Carotid Stump Pressure in Carotid Endarterectomy: A Systematic Review and Meta-Analysis

This review evaluates the carotid stump pressure (CSP)’s role as a single parameter at any given pressure as an indicator for selective shunting, or vice versa, in carotid endarterectomy (CEA). A systematic review of literature in MEDLINE and the Cochrane Library from 1969 to 2019 was conducted. The primary end point was set at 0 to 30-day mortality, ischemic stroke (IS), transient ischemic attack (TIA), and a secondary point at recognition of an optimal CSP pressure. The data was subjected to meta-analytics. The odds ratio (OR) was reported at 95% confidence interval (CI). This study has been registered with PROSPERO: CRD42019119851. The pooled analysis on the primary endpoint of IS demonstrated higher incidence of stroke in shunted CEAs solely based on CSP measurement alone (OR, 0.14, 95%CI: 0.08–0.24, I²=48%, p<0.001). Sub group analysis demonstrated similar patterns at 25 mmHg (OR, 0.06, 95%CI: 0.01–0.5, p<0.01), 30 mmHg (OR, 0.07, 95%CI: 0.01–0.63, p=0.02) and 40 mmHg (OR, 0.23, 95%CI: 0.09–0.57, p<0.01). This effect on end points of mortality and TIA demonstrated no benefit in either direction. CSP, as a single criterion, is not a reliable parameter in reduction of TIA, mortality, and IS at any given pressure range.

The Effect of Metabolic Syndrome on the Occurrence of Restenosis After Carotid Endarterectomy

OBJECTIVES

The metabolic syndrome (MetS) is a cluster of risk factors for cardiovascular disease. The effect of MetS on clinical outcome in patients with cerebrovascular disease remains largely unknown because conflicting results have been published. This study aimed to determine the influence of MetS on the occurrence of restenosis after carotid endarterectomy (CEA).

METHODS

All patients who underwent CEA between June 2003 and December 2014 in two tertiary academic referral centres in The Netherlands were included. MetS was defined if three or more of the following criteria were present: hypertension, obesity, high fasting serum blood glucose, high serum triglycerides, or low serum high density lipoprotein cholesterol. The primary outcome measure was the occurrence of ipsilateral restenosis after index surgery. The secondary outcome measure was (all cause) mortality during follow up. For the primary analysis, missing data were multiply imputed using multivariable imputation by chained equations. A Cox proportional hazards model was used to perform an adjusted analysis on the multiply imputed data sets.

RESULTS

A total of 1668 CEA procedures (in 1577 patients) were performed. The presence or absence of MetS could not be determined in 263 patients because of missing data. There was no significant difference in freedom from restenosis in the MetS group vs. the no-MetS group (hazard ratio [HR], 1.10; 95% confidence interval [CI] 0.98-1.23; p = .10) or in all cause mortality (HR 1.20; 95% CI 0.94-1.54; p = .14).

CONCLUSION

This study shows that MetS does not predict restenosis after CEA. Also, the presence of MetS did not influence patient survival negatively.

Multicentre prospective cohort study of nonoperative versus operative treatment for flail chest and multiple rib fractures after blunt thoracic trauma: study protocol

INTRODUCTION

A trend has evolved towards rib fixation for flail chest although evidence is limited. Little is known about rib fixation for multiple rib fractures without flail chest. The aim of this study is to compare rib fixation with nonoperative treatment for both patients with flail chest and patients with multiple rib fractures.

METHODS AND ANALYSIS

In this study protocol for a multicentre prospective cohort study, all patients with three or more rib fractures admitted to one of the five participating centres will be included. In two centres, rib fixation is performed and in three centres nonoperative treatment is the standard-of-care for flail chest or multiple rib fractures. The primary outcome measures are intensive care unit length of stay and hospital length of stay for patients with a flail chest and patients with multiple rib fractures, respectively. Propensity score matching will be used to control for potential confounding of the relation between treatment modality and length of stay. All analyses will be performed separately for patients with flail chest and patients with multiple rib fractures without flail chest.

ETHICS AND DISSEMINATION

The regional Medical Research Ethics Committee UMC Utrecht approved a waiver of consent (reference number WAG/mb/17/024787 and METC protocol number 17-544/C). Patients will be fully informed of the purpose and procedures of the study, and signed informed consent will be obtained in agreement with the General Data Protection Regulation. Study results will be submitted for peer review publication.

TRIAL REGISTRATION NUMBER

NTR6833.

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.