Regional or general anesthesia for carotid endarterectomy? Evidence from published prospective and retrospective studies

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.

Peri-Procedural Management of Hemodynamic Instability in Patients Undergoing Carotid Revascularization

Acute perioperative changes in arterial pressure occur frequently, particularly in patients with cardiovascular disease or those receiving vasoactive medications, or in relation to certain cardiovascular surgical procedures. Hemodynamic Instability (HI) are common in patients undergoing carotid revascularization because of unique patho-physiological and surgical factors. The operation, by necessity, disrupts the afferent pathway of the baroreflex, which can lead to postendarterectomy HI. Poor arterial pressure control is associated with increased morbidity and mortality after carotid revascularization, but good control of arterial pressure is often difficult to achieve in practice. The incidence, implications, and etiology of HI associated with carotid surgery are reviewed, and some recommendations made for its management. Close monitoring and titration of therapy are probably the most important considerations rather than specific choice of agents.

An Enhanced Recovery After Surgery Protocol Decreases the Use of Narcotics in Infrainguinal Bypass Patients

OBJECTIVES

"Enhanced recovery after surgery" (ERAS) protocols use a multisystem approach to target homeostatic physiology via opioid-minimizing analgesia. The aim of this study is to determine if an ERAS protocol for lower extremity bypass surgery improves pain control and decreases narcotics.

METHODS

From July 2020 through June 2021, all patients that underwent infrainguinal lower extremity bypass procedures were subject to the ERAS protocol and compared to a "pre-ERAS" group between June 2016 through May 2020. Preoperatively, ERAS patients were given celecoxib, gabapentin, and acetaminophen while postoperatively they were given standing acetaminophen, gabapentin, ketorolac, and tramadol with as needed use of oxycodone. Pain scores were recorded using a numerical rating pain scale. Demographics, length of stay, 30-day complications, and disposition metrics were recorded.

RESULTS

There were 50 patients in the ERAS group, compared to 114 before its implementation. The mean age was 70.5 (ERAS group) versus 68.7 (pre-ERAS group) and a majority were male (P > .05). Enhanced recovery after surgery patients were less likely to have chronic kidney disease (P = .01). Enhanced recovery after surgery patients had improved length of stay (3.6 ± 2.3 days vs 4.8 ± 3.2 days, ERAS vs pre-ERAS, P = .01). There was no significant difference between groups for the remaining demographics (P > .05). One patient (2%) in the ERAS group used patient-controlled analgesia, compared to 30 patients (26%) in the pre-ERAS group (P < .001). Cumulative pain control in the first 12 hours was significantly better in the ERAS group (P = .05). Pain control at discharge was similar between the 2 groups (3 pain score vs 3 pain score, pre-ERAS vs ERAS, P > .05).

CONCLUSION

Our study utilized a multisystem approach to optimize the physiologic stress response to vascular surgery while reducing high potency narcotic use. We show that an ERAS protocol provides noninferior pain control with less potent pain medication and improves the length of stay for patients undergoing infrainguinal bypass surgery.

Intraoperative Cerebral Monitoring During Carotid Surgery: A Narrative Review

BACKGROUND

Intra-operative neurological monitoring (IONM) during carotid endarterectomy (CEA) aims to reduce neurological morbidity of surgery.

OBJECTIVE

This narrative review analyses the role and results of different methods of IONM.

METHODS

review articles on PUBMED and Cochrane Library, by searching key words related to IONM and CEA, from 2000 up to date.

RESULTS

regional anesthesia in some centers represents the "gold standard". The most often used alternative techniques are: stump pressure, electroencephalogram, somatosensory evoked potentials, transcranical doppler ultrasound, near infrared spectroscopy and routine shunting. Every technique shows limitations. Regional anesthesia can make difficult prompt intubation when needed. Stump pressure shows a wide operative range. Electroencephalogram is unable to detect ischemia in sub-cortical regions of the brain. Somatosensory evoked potentials certainly demonstrate the presence of cerebral ischemia, but are no more specific or sensitive than the electroencephalogram. Transcranical doppler monitoring is undoubtedly operator-dependent and suffers from the limitations that the probe has to be placed relatively near to the surgical site and may impede the operator, especially if it needs constant adjustments; moreover, an acoustic window may not be found in 10% -20% of the subjects. Near infrared spectroscopy appears to have a high negative predictive value for cerebral ischemia, but has a poor positive predictive value and low specificity, because predominantly estimates venous oxygenation as this makes up about 80% of cerebral blood volume. The data on the use of Routine Shunting (RS) from RCTs are limited.

CONCLUSIONS

currently, with no clear consensus on monitoring technique, choice should be guided by local expertise and complication rates. With reflection, best practice may dictate that a standard technique is selected as suggested above and this remains the default position for individual practice. Nevertheless, current techniques for monitoring cerebral perfusion during CEA are associated with false negative and false positive resulting in inappropriate shunt insertion.

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.

[Peripheral Regional Anaesthesia for Perioperative Analgesia]

Peripheral Regional Anaesthesia for Perioperative Analgesia Abstract. Peripheral regional anaesthesia is the actual gold standard of opioid-sparing perioperative analgesia and is mainly used for surgery of the shoulder, arm and leg. Well-trained anaesthesiologists are the prerequisite for the correct individual risk-benefit assessment and the performance of the nerve blocks using a combination of ultrasound guidance and peripheral nerve stimulation (dual guidance). The postoperative care of the patients requires trained staff.

Enhanced Recovery after Vascular Surgery

The beginnings of the enhanced recovery after surgery (ERAS) program were first developed for patients in colorectal surgery, and after it was established as the standard of care in this surgical field, it began to be applied in many others surgical areas. This is multimodal, evidence-based approach program and includes simultaneous optimization of preoperative status of patients, adequate selection of surgical procedure and postoperative management. The aim of this program is to reduce complications, the length of hospital stay and to improve the patients outcome. Over the past decades, special attention was directed to the postoperative management in vascular surgery, especially after major vascular surgery because of the great risk of multiorgan failure, such as: respiratory failure, myocardial infarction, hemodynamic instability, coagulopathy, renal failure, neurological disorders, and intra-abdominal complications. Although a lot of effort was put into it, there is no unique acceptable program for ERAS in this surgical field, and there is still a need to point out the factors responsible for postoperative outcomes of these patients. So far, it is known that special attention should be paid to already existing diseases, type and the duration of the surgical intervention, hemodynamic and fluid management, nutrition, pain management, and early mobilization of patients.

Local anaesthetic infiltration at the end of carotid endarterectomy improves post-operative analgesia

BACKGROUND

Wound infiltration at the end of carotid endarterectomy under general anaesthesia is a simple technique that can be delegated to the surgeon. It was hypothesised that this technique could improve early post-operative analgesia by reducing the need for post-operative opioids.

METHODS

Forty patients underwent carotid endarterectomy under general anaesthesia with desflurane and remifentanil supplemented with morphine for post-operative analgesia. In a prospective double-blinded randomised study, patients were allocated pre-operatively to receive either subcutaneous infiltration of both wound edges with 20 ml of 0.75% ropivacaine or infiltration with isotonic saline. The primary outcome was morphine consumption while in the post-anaesthesia care unit (PACU). Pain scores at rest and movement, sedation, and patient satisfaction were the other main outcomes used to assess post-operative analgesia.

RESULTS

The median dose of morphine administered in the PACU was 2 mg [0-3] in the ropivacaine vs. 4 mg [3-6] in the placebo group (P = 0.0004, Mann-Whitney's test). Pain at rest and at movement was lower in the ropivacaine group throughout observation in the PACU. No difference was found for both pain and opioid consumption after discharge from the PACU or for patient satisfaction. Sedative events in the early post-operative period were less frequent in the ropivacaine group.

CONCLUSIONS

Local anaesthetic wound infiltration performed before closure reduces the need for additional opioids, lowers the immediate post-operative pain and improves alertness. These results argue for the use of local infiltration anaesthesia for carotid endarterectomy.

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.

Enhanced recovery after vascular surgery: protocol for a systematic review

BACKGROUND

The enhanced recovery after surgery (ERAS) programme is a multimodal evidence-based approach to surgical care which begins in the preoperative setting and extends through to patient discharge in the postoperative period. The primary components of ERAS include the introduction of preoperative patient education; reduction in perioperative use of nasogastric tubes and drains; the use of multimodal analgesia; goal-directed fluid management; early removal of Foley catheter; early mobilization, and early oral nutrition. The ERAS approach has gradually evolved to become the standard of care in colorectal surgery and is presently being used in other specialty areas such as vascular surgery. Currently there is little evidence available for the implementation of ERAS in this field. We plan to conduct a systematic review of this literature with a view to incorporating ERAS principles into the management of major elective vascular surgery procedures.

METHODS

We will search EMBASE (OVID, 1947 to June 2012), Medline (OVID, 1948 to June 2012), and Cochrane Central Register of Controlled Trials (Wiley, Issue 1, 2012). Searches will be performed with no year or language restrictions. For inclusion, studies must look at adult patients over 18 years. Major elective vascular surgery includes carotid, bypass, aneurysm and amputation procedures. Studies must have evaluated usual care against an ERAS intervention in the preoperative, perioperative or postoperative period of care. Primary outcome measures are length of stay, decreased complication rate, and patient satisfaction or expectations. Only randomized controlled trials will be included.

DISCUSSION

Most ERAS approaches have been considered in the context of colorectal surgery. Given the increasing use of multiple yet different aspects of this pathway in vascular surgery, it is timely to systematically review the evidence for their independent or combined outcomes, with a view to implementing them in this clinical setting. Results from this review will have important implications for vascular surgeons, anaesthetists, nurses, and other health care professionals when making evidenced-based decisions about the use of ERAS in daily practice.

Wake-up test decrease shunts insertion during carotid endarterectomy under general anesthesia

OBJECTIVE

The use of locoregional anesthesia versus general anesthesia (GE) in carotid endarterectomy (CEA) has been a debatable issue in clinical studies for the past several years. In our study, GE with wake-up tests (WUTs) during carotid cross-clamping was used instead of stump pressure (SP) to directly assess the neurological status of the patient to determine whether shunting was needed. Our study assessed the percentage of patients under light sedation and mechanically ventilated needing shunting based on WUT compared to a systolic stump pressure (SPs) cutoff value of <or=40 mm Hg.

DESIGN

Retrospective, observational study.

SETTING

University hospital clinic.

PARTICIPANTS

Three hundred fifty-one patients (American Society of Anesthesiologists physical class II-III) with carotid artery stenosis scheduled for CEA under GE.

INTERVENTIONS

The WUT was used to assess the neurological status in patients undergoing CEA, which involved the gradual reduction of depth of anesthesia until the patient was capable of responding to a verbal stimulus and provide full collaboration while only receiving remifentanil. A positive WUT indicated that patient was not able to carry out the order.

MEASUREMENTS AND MAIN RESULTS

Of 343 patients, 20 (5.8%) were shunted due to a positive WUT after cross-clamping in comparison to 45 patients (12.8%) based on the SPs <or=40 mm Hg criteria.

CONCLUSION

Wake-up test can be used to directly assess the neurological status in patients undergoing CEA to determine whether shunting is required. Our results showed that less patients required shunting based on WUT compared to the SP criteria.

Neuroprotective effect of volatile anesthetic agents: molecular mechanisms

INTRODUCTION

Intra-operative cerebral ischemia can be catastrophic, and volatile anesthetic agents have been recognized for their potential neuroprotective properties since the 1960s. In this review, we examine the neuroprotective effects of five volatile anesthetic agents in current or recent clinical use: isoflurane, sevoflurane, desflurane, halothane and enflurane.

METHODS

A review of publications in the National Library of Medicine and National Institutes of Health database from 1970 to 2007 was conducted.

RESULTS

Volatile anesthetic agents have been shown to be neuroprotective in multiple animal works of ischemic brain injury. Short-term neuroprotection (<1 week post-ischemia) in experimental cerebral ischemia has been reported in multiple works, although long-term neuroprotection (> or = 1 week post-ischemia) remains controversial. Comparison works have not demonstrated superiority of one specific volatile agent over another in experimental models of brain injury. Relatively few human works have examined the protective effects of volatile anesthetic agents and conclusive evidence of a neuroprotective effect has yet to emerge from human works.

CONCLUSION

Proposed mechanisms related to the neuroprotective effect of volatile anesthetic agents include activation of ATP-dependent potassium channels, up-regulation of nitric oxide synthase, reduction of excitotoxic stressors and cerebral metabolic rate, augmentation of peri-ischemic cerebral blood flow and up-regulation of antiapoptotic factors including MAP kinases.

A study of cognitive dysfunction in patients having carotid endarterectomy performed with regional anesthesia

BACKGROUND

In previous studies, we found that approximately 25% of patients having carotid endarterectomy with general anesthesia (CEA general) develop cognitive dysfunction compared with a surgical control Group 1 day and 1 mo after surgery. In this study, we tested the hypothesis that patients having CEA with regional anesthesia (CEA regional) will develop significant cognitive dysfunction 1 day after surgery compared with a control group of patients receiving sedation 1 day after surgery. We did not study persistence of dysfunction.

METHODS

To test this hypothesis, we enrolled 60 patients in a prospective study. CEA regional was performed with superficial and deep cervical plexus blocks in 41 patients. The control group consisted of 19 patients having coronary angiography or coronary artery stenting performed with sedation. A control group is necessary to account for the "practice effect" associated with repeated cognitive testing. The patients from the CEA regional group were enrolled at New York Medical Center and the control group at Columbia-Presbyterian Medical Center. The cognitive performance of all patients was evaluated using a previously validated battery of neuropsychometric tests. Differences in performance, 1 day after compared with before surgery, were evaluated by both event-rate and group-rate analyses.

RESULTS

On postoperative day 1, 24.4% of patients undergoing CEA regional had significant cognitive dysfunction, where "significant" was defined as a total deficit score > or =2 SD worse than the mean performance in the control group.

CONCLUSIONS

Patients undergoing CEA regional had an incidence of cognitive dysfunction which was not different than patients having CEA general as previously published and compared with a contemporaneously enrolled group.