Local versus General Anaesthesia for Carotid Endarterectomy – Improving the Gold Standard ?

Effect of regional versus general anesthesia on thirty-day outcomes following carotid endarterectomy: a cohort study

BACKGROUND

The effect of regional versus general anesthesia on carotid endarterectomy outcomes is debated. This study assesses the effect of anesthetic technique on major morbidity and mortality and additional secondary endpoints following carotid endarterectomy.

MATERIALS AND METHODS

This was a retrospective propensity-matched-cohort analysis investigating elective carotid endarterectomy patients in the 2015-2019 American College of Surgeons National Surgical Quality Improvement Program ( n =37 204). The primary endpoint was 30-day mortality and major morbidity, defined as stroke, myocardial infarction, or death. Secondary endpoints included minor morbidity, bleeding events, healthcare resource utilization, and length of hospital stay. Univariate, multivariable, and survival analyses were applied.

RESULTS

The 1 : 1 propensity-matched-cohort included 8304 patients (4152 in each group). Regional anesthesia was associated with similar incidences of major morbidity and mortality [odds ratio (OR), 0.81 (95% CI, 0.61-1.09); P = 0.162] and unplanned resource utilization [OR, 0.93 (95% CI, 0.78-1.11); P = 0.443], but lower incidences of minor morbidity [OR, 0.60 (95% CI, 0.44-0.81); P < 0.001] and bleeding events [OR, 0.49 (95% CI, 0.30-0.78); P = 0.002], and a shorter length of hospital stay [1.4 vs. 1.6 days; mean difference, -0.16 days (95% CI, -0.25 to -0.07); P < 0.001]. On multivariable analysis, regional anesthesia remained independently predictive of minor morbidity [adjusted odds ratio (AOR), 0.58 (95% CI, 0.42-0.79); P = 0.001] and bleeding events [AOR, 0.49 (95% CI, 0.30-0.77); P = 0.003]. Significance was maintained on survival analysis for these two endpoints. A mortality benefit was observed on univariate [OR, 0.50 (95% CI, 0.25-1.00); P = 0.045], multivariable [AOR, 0.49 (95% CI, 0.24-0.96); P = 0.043], and survival analysis ( P = 0.045).

CONCLUSIONS

Carotid endarterectomy patients receiving regional anesthesia experience favorable outcomes compared to propensity-matched general anesthesia controls.

Regional Anesthesia for Vascular Surgery and Pain Management

Patients undergoing vascular surgery tend to have significant systemic comorbidities. Vascular surgery itself is also associated with greater cardiac morbidity and overall mortality than other types of noncardiac surgery. Regional anesthesia is amenable as the primary anesthetic technique for vascular surgery or as an adjunct to general anesthesia. When used as the primary anesthetic, regional anesthesia techniques avoid complications associated with general anesthesia in this challenging patient population. In this article, the authors describe regional anesthetic techniques for carotid endarterectomy, arteriovenous fistula creation, lower extremity bypass surgery, and amputation.

Utilization and Outcomes of Local Anesthesia and Peripheral Nerve Block for Hybrid Lower Extremity Revascularization

Purpose: To investigate the utilization of local anesthesia or peripheral nerve block with monitored anesthesia care (LPMAC) and its impact on the perioperative outcomes of hybrid lower extremity revascularization (LER) compared with general anesthesia (GA). Materials and Methods: A search of the ACS-NSQIP database between 2005 and 2017 identified 9430 patients who underwent hybrid LER for peripheral artery disease. Excluding 449 ineligible cases left 8981 hybrid LER patients for analysis. The patients were dichotomized based on the anesthetic technique: 8631 (96.1%) GA and 350 (3.9%) LPMAC. The GA patients were matched 3:1 based on propensity scores to patients in the LPMAC group based on gender, age, race, functional status, transfer status, chronic obstructive pulmonary disease (COPD), dialysis status, American Society of Anesthesiologists (ASA) class, emergent surgery, preoperative sepsis, indication, and type of open and endovascular procedure. Outcomes including complications, mortality, procedure time, and hospital length of stay were compared between the matched groups (801 GA vs 267 LPMAC). Results: Comparing the unmatched groups, those treated under LPMAC were older (72.7±9 vs 68±8.4 years, p<0.001) and had higher rates of COPD (24.3% vs 17%, p=0.001), dialysis dependence (8.1% vs 4.2%, p=0.002), preoperative sepsis (6.6% vs 4.2%, p=0.029), and ASA class ≥IV (29.1% vs 24.1%, p=0.036) than in the unmatched GA cohort. In the matched comparison, LPMAC was associated with lower overall morbidity (25.5% vs 32.3%, p=0.042) and shorter operating time (202.7±98 vs 217.7±102 minutes, p=0.034) compared with GA. The rate of myocardial infarction was lower (1.1% vs 2.4%) and ventilator use for >48 hours was less frequent (0.4% vs 2.6%) for LPMAC patients, though statistical significance was not reached. There was no difference in mortality or hospital length of stay. Conclusion: LPMAC is an infrequent anesthetic technique for hybrid LER and is primarily used for patients with a high burden of comorbidities. LPMAC is associated with reduced overall morbidity and operating time. Further studies are needed to identify which patients undergoing hybrid LER benefit most from LPMAC.

General Anesthesia Versus Local Anesthesia in Carotid Endarterectomy: A Systematic Review and Meta-Analysis

OBJECTIVE

The choice of anesthetic technique in carotid endarterectomy (CEA) has been controversial. This study compared the outcomes of general anesthesia (GA) and local anesthesia (LA) in CEA.

DESIGN

Systematic review and meta-analysis of comparative studies.

SETTING

Hospitals.

PARTICIPANTS

Adult patients undergoing CEA with either LA or GA.

INTERVENTIONS

The effects of GA and LA on CEA outcomes were compared.

MEASUREMENTS AND MAIN RESULTS

PubMed, OVID, Scopus, and Embase were searched to June 2018. Thirty-one studies with 152,376 patients were analyzed. A random effect model was used, and heterogeneity was assessed with the I² and chi-square tests. LA was associated with shorter surgical time (weighted mean difference -9.15 min [-15.55 to -2.75]; p = 0.005) and less stroke (odds ratio [OR] 0.76 [0.62-0.92]; p = 0.006), cardiac complications (OR 0.59 [0.47-0.73]; p < 0.00001), and in-hospital mortality (OR 0.72 [0.59-0.90]; p = 0.003). Transient neurologic deficit rates were similar (OR 0.69 [0.46-1.04]; p = 0.07). Heterogeneity was significant for surgical time (I² = 0.99, chi-square = 1,336.04; p < 0.00001), transient neurologic deficit (I² = 0.41, chi-square = 28.81; p = 0.04), and cardiac complications (I² = 0.42, chi-square = 43.32; p = 0.01) but not for stroke (I² = 0.22, chi-square = 30.72; p = 0.16) and mortality (I² = 0.00, chi-square = 21.69; p = 0.65). Randomized controlled trial subgroup analysis was performed, and all the aforementioned variables were not significantly different or heterogenous.

CONCLUSION

The results from this study showed no inferiority of using LA to GA in patients undergoing CEA. Future investigations should be reported more systematically, preferably with randomization or propensity-matched analysis, and thus registries will facilitate investigation of this subject. Anesthetic choice in CEA should be individualized and encouraged where applicable.

A Cost Analysis of Regional Versus General Anesthesia for Carotid Endarterectomy

BACKGROUND

Medical care in the United States has evolved into a more cost-conscious value-based health care system that necessitates a comparison of costs when there are alternative interventions considered to be acceptable in the treatment of a disease. This study compares the cost differences between regional anesthesia (RA) and general anesthesia (GA) for carotid endarterectomy (CEA).

METHODS

Data from 346 consecutive patients who underwent CEA between January 2012 and September 2014 were retrospectively reviewed for the type of anesthesia used, outcomes data, and cost variables. Overall hospital day costs were compared between RA and GA. Medians and interquartile ranges were compared using Wilcoxon-Mann-Whitney test. A P < 0.05 was considered statistically significant using 2-sided tests.

RESULTS

Median overall costs for GA were significantly higher than median costs for RA (medians [with interquartile ranges], $10,140 [$7,158-$12,658] versus $7,122 [$5,072-$8,511], P < 0.001). Median total operative time for GA was significantly longer than median time for RA (168 [144-188] versus 134 [115-147] min, P < 0.001). Median in-hospital length of stay (LOS) for GA was significantly longer compared with RA (2.0 vs 1.2 days, P < 0.001). Patients who received GA were also more likely to be admitted to the intensive care unit.

CONCLUSIONS

Decreased cost, operating room expenses, postoperative resources, and overall LOS were observed for individuals who underwent RA for CEA as compared with GA. In summary, RA is more cost-effective and should be the optimal choice when clinically appropriate.

Locoregional Anesthesia for Carotid Endarterectomy: Identification of Patients with Intolerance to Cross-Clamping

OBJECTIVE

During carotid endarterectomy (CEA), carotid cross-clamping is performed to allow for artery incision and plaque removal. A small subgroup of patients can tolerate carotid occlusion for only a few seconds, if at all, without presenting neurologic deficit. These patients are described as having ''cross-clamp intolerance.'' The purpose of this study was to demonstrate the safety of locoregional anesthesia in identifying patients with cross-clamp intolerance and factors associated with this condition.

METHODS

From August 2008 to May 2010, 115 consecutive patients were submitted to CEA under locoregional anesthesia at the Santa Casa de Belo Horizonte; the procedure was performed by the main author. Patients who showed intolerance to internal carotid artery (ICA) occlusion for <30 seconds were considered to have cross-clamp intolerance.

RESULTS

Among the 115 participating patients, 9.6% (11 patients) showed intolerance to ICA occlusion and developed deficits in <30 seconds (i.e., these patients presented cross-clamp intolerance). The factor that was associated with cross-clamp intolerance was the mean degree of contralateral carotid stenosis, which was 57.5% for those who presented intolerance and 27.8% for those who tolerated ICA occlusion.

CONCLUSION

Locoregional anesthesia is a safe method for identifying patients with cross-clamp intolerance. Patients with cross-clamp intolerance present contralateral stenosis that is greater on average than patients who readily tolerate carotid artery occlusion.

Regional anesthesia for vascular surgery

Patients presenting for vascular surgery present a challenge to anesthesiologists because of their severe systemic comorbidities. Regional anesthesia has been used as a primary anesthetic technique for many vascular procedures to avoid the cardiovascular and pulmonary perturbations associated with general anesthesia. In this article the use of regional anesthesia for carotid endarterectomy, open and endovascular abdominal aortic aneurysm repair, infrainguinal arterial bypass, lower extremity amputation, and arteriovenous fistula formation is described. A focus is placed on reviewing the literature comparing anesthetic techniques, with brief descriptions of the techniques themselves.

Comparison Between Local and General Anesthesia for Carotid Endarterectomy: Early and Late Results

Background: The aim of this retrospective study was to compare the results between general and local anesthesia (LA) for carotid endarterectomy (CEA). Methods: Three hundred and twenty-nine patients in whom 365 CEA procedures were performed between January 1990 and September 2001, were included in this study. Results: Operation time, shunt usage rates, hospitalization time ( P < .0001), and permanent stroke rates ( P < .05) were significantly lower in group with LA. For long-term period (121.3 ± 37.45 vs 98.6 ± 28.98 months), no significant difference was observed in these 2 group with respect to restenosis rates, neurological events, and deaths. Conclusions: Despite the lack of significant difference between LA and general anesthesia in terms of restenosis, neurological events, and death in the long-term period; LA is more preferable due its associated advantages including availability of testing the consciousness of the patients by direct contact, reduced use of shunts, shorter hospitalization periods, and less prevalence of permanent stroke in the short-term period.

Cerebral oximetry and stump pressure as indicators for shunting during carotid endarterectomy: comparative evaluation

The purpose of this work is to investigate the correlation between regional oxygen saturation (rSO2) changes and stump pressure (SP) during cross-clamping of the internal carotid artery in carotid endarterectomy (CEA) and verify the perspectives of rSO2 to become a criterion for shunting. Sixty consecutive CEAs under general anesthesia were studied prospectively. Selective shunting was based on SP ≤40 mmHg exclusively. Regression analysis with high order terms and receiver operating characteristic analysis were performed to investigate the association between ΔrSO2(%) and SP and to determine an optimal ΔrSO2(%) threshold for shunt insertion. A quadratic association between ΔrSO2(%) and SP was documented regarding the baseline to one and five minutes after cross-clamping intervals. A cut-off of 21 and 10.1% reduction from the baseline recording was identified as optimal for the distinction between patients needed or not a shunt regarding the first and fifth minute after cross-clamping, respectively. In conclusion, cerebral oximety reflects sufficiently cerebral oxygenation during CEA compared with SP, providing a useful mean for cerebral monitoring.

General or Local Anesthesia for Carotid Endarterectomy—The “Real-World” Experience

Perioperative complications from carotid endarterectomy (CEA) are the main drawbacks of the procedure. The aim of this study was to assess the complication rates in patients undergoing CEA under general anesthesia (GA) or regional anesthesia (local anesthesia [LA]) at our institution. Patients undergoing CEA at our regional vascular unit between 2000 and 2004 were included. Data were collated retrospectively from a prospective database. Follow-up was up to 62 months. In all, 383 endarterectomies were performed, 260 of which were under LA. Outcome measures included 30-day death (2.1%), stroke (1.8%), and combined stroke and death (2.8%). A 30-day incidence of stroke, death, and combined stroke and death was lower in the LA group. Incidence of myocardial infarction and transient ischemic attacks, and annual mortality were higher in the LA group. No significant difference was found between the 2 groups. In a unit where CEA is preferentially performed under LA, anesthesia technique failed to significantly influence outcome.

Protamine reduces bleeding complications associated with carotid endarterectomy without increasing the risk of stroke

OBJECTIVES

Controversy persists regarding the use of protamine during carotid endarterectomy (CEA) based on prior conflicting reports documenting both reduced bleeding as well as increased stroke risk. The purpose of this study was to determine the effect of protamine reversal of heparin anticoagulation on the outcome of CEA in a contemporary multistate registry.

METHODS

We reviewed a prospective regional registry of 4587 CEAs in 4311 patients performed by 66 surgeons from 11 centers in Northern New England from 2003-2008. Protamine use varied by surgeon (38% routine use, 44% rare use, 18% selective use). Endpoints were postoperative bleeding requiring reoperation as well as potential thrombotic complications, including stroke, death, and myocardial infarction (MI). Predictors of endpoints were determined by multivariate logistic regression after associated variables were identified by univariate analysis.

RESULTS

Of the 4587 CEAs performed, 46% utilized protamine, while 54% did not. Fourteen patients (0.64%) in the protamine-treated group required reoperation for bleeding compared with 42 patients (1.66%) in the untreated cohort (P = .001). Protamine use did not affect the rate of MI (1.1% vs 0.91%, P = .51), stroke (0.78% vs 1.15%, P = .2), or death (0.23% vs 0.32%, P = .57) between treated and untreated patients, respectively. By multivariate analysis, protamine (odds ratio [OR] 0.32, 95% confidence interval [CI], 0.17-0.63; P = .001) and patch angioplasty (OR 0.46, 95% CI, 0.26-0.81; P = .007) were independently associated with diminished reoperation for bleeding. A single center was associated with a significantly higher rate of reoperation for bleeding (OR 6.47, 95% CI, 3.02-13.9; P < .001). Independent of protamine use, consequences of reoperation for bleeding were significant, with a four-fold increase in MI, a seven-fold increase in stroke, and a 30-fold increase in death.

CONCLUSION

Protamine reduced serious bleeding requiring reoperation during CEA without increasing the risk of MI, stroke, or death, in this large, contemporary registry. In light of significant complications referable to bleeding, liberal use of protamine during CEA appears warranted.