Local anesthesia for endovascular abdominal aortic aneurysm repair

Endovascular aneurysm repair: a perioperative perspective

Endovascular aneurysm repair (EVAR), has surpassed open repair as the technique of choice in many centres in response to several large studies which showed significantly improved 30-day mortality. While several multicentre EVAR trials looked at surgical outcomes, very few have specifically investigated the effect of anaesthetic techniques or perioperative care of these patients. The purpose of this review to is to present some of the current evidence for the different aspects of perioperative management of patients undergoing EVAR. This includes surgical considerations, pre-operative assessment, and choice of anaesthetic technique as well as pharmacological protective strategies.

Early results of the Endurant endograft system in patients with friendly and hostile infrarenal abdominal aortic aneurysm anatomy

OBJECTIVE

To evaluate and compare the outcome after endovascular abdominal aortic aneurysm repair (EVAR) with the newly released Endurant endograft system in patients with different aortoiliac anatomic characteristics.

METHODS

We conducted a prospective observational study assigning patients with infrarenal abdominal aortic aneurysm (AAA) treated with the Endurant endoprosthesis from February 2009 to March 2010. Two groups were studied, according to the presence of a friendly (group I [GI] = 43) or hostile (group II [GII] = 34) infrarenal aortoiliac anatomy. Hostile profile was defined as any (or combination) of the following measurements: 5 mm ≤ proximal neck length (Lpr) ≤ 12 mm, 60° < proximal neck angle (A°pr) ≤ 90° and 60° < any iliac axis angle (A°iliac) ≤ 90°. Primary end points included technical and clinical success, freedom from early or late secondary interventions, any type of endoleak, and aneurysm-related death. All outcome measures were calculated using the Kaplan-Meier method and the log rank test was applied for comparisons between the groups.

RESULTS

The mean comorbid severity scoring was higher in GII (P = .018). The mean follow-up period in GI and GII was 12.9 ± 3.9 months (± SD, range: 6.4-19.8) and 12.4 ± 4 months (range: 4.2-19.6), respectively. Two unplanned conversions to aortouniiliac configurations were required in GI. The technical success rate in GI and GII was 95.4% and 100%, respectively. The requirement for intentional occlusion of the internal iliac artery, the requirement for cross-limb technique, the necessity of troubleshooting techniques, the procedure and radiation times, the frequency of postimplantation syndrome, and mean hospital stay were significantly higher in GII (P = .028, P = .013, P = .005, P = .037, P < .001, P = .032, P = .021, respectively). Two patients of GI died in the early postoperative period (one aneurysm but not device-related death), whereas no deaths in GII were recorded, yielding an overall 30-day mortality rate of 2.3%. No type I/III endoleaks were recorded up to the end of the study. Freedom from any type of endoleak, early or late secondary interventions, and aneurysm-related death at 12 months were found in 93.2%, 87.1%, and 93.3% of GI patients; respective values for GII were 86% (P = .21), 93.4% (P = .066), and 93.4%. The clinical success rate was 82.1% and 100% at 12 months for GI and GII, respectively.

CONCLUSIONS

Early (12 months) results suggest similar clinical performance of the Endurant stent graft system in endovascular treatment of AAAs with friendly and hostile anatomies, however, demonstrating more intra- and perioperative adversities for the last group. Larger prospective studies or even randomized trials comparing different new generation graft models are required to evaluate the comparable long-term results and possible expansion of EVAR indications for this specific endograft in adverse anatomies.

Results of endovascular aortic aneurysm repair with general, regional, and local/monitored anesthesia care in the American College of Surgeons National Surgical Quality Improvement Program database

BACKGROUND

This study examined outcomes of endovascular repair of infrarenal abdominal aortic aneurysms (EVAR) using general, spinal, epidural, and local/monitored anesthesia care (MAC) in a multicenter North American hospital database reflecting contemporary anesthesia and surgical practices.

METHODS

Elective EVAR cases performed between 2005 and 2008 were identified from the American College of Surgeons National Surgical Quality Improvement Program database using Current Procedural Terminology codes. Excluded were emergency cases and patients with concomitant procedures requiring general anesthesia. Patient-level comorbidities, characteristics, and intraoperative and postoperative details were examined. Complications were analyzed individually and in aggregate categories, including wound, pulmonary, renal, venous thromboembolic, cardiovascular, operative, and septic. Length of stay (LOS) and 30-day mortality were examined. Characteristics and outcomes were described using mean ± standard deviation or count (%), and comparisons were evaluated for statistical significance using χ(2), Fisher exact test, and univariate linear regression. LOS was analyzed with linear regression techniques using a log transformation. Associations between anesthesia type and outcomes were examined using univariable and multivariable regression techniques.

RESULTS

We identified 6009 elective EVAR procedures for analysis. General anesthesia was used in 4868 cases, spinal anesthesia in 419, epidural anesthesia in 331, and local/MAC in 391. Defined morbidity occurred in 11% of patients. Median LOS was 2 (interquartile range, 1-3) days, and mean LOS was 2.8 ± 4.3 days. The 30-day mortality rate was 1.1%. Significant multivariate associations were observed between anesthesia type, pulmonary morbidity, and log-LOS. General anesthesia was associated with an increase in pulmonary morbidity vs spinal (odds ratio [OR], 4.0; 95% confidence interval [CI], 1.3-12.5; P = .020) and local/MAC anesthesia (OR, 2.6; 95% CI, 1.0-6.4; P = .041). Use of general anesthesia was associated with a 10% increase in LOS for general vs spinal anesthesia (95% CI, 4.8%-15.5%; P = .001) and a 20% increase for general vs local/MAC anesthesia (95% CI, 14.1%-26.2%; P < .001). Trends toward increased pulmonary morbidity and LOS were not observed for general vs epidural anesthesia. No significant association between anesthesia type and mortality was observed.

CONCLUSIONS

In contemporary North American anesthetic and surgical practice, general anesthesia for EVAR was associated with increased postoperative LOS and pulmonary morbidity compared with spinal and local/MAC anesthesia. These data suggest that increasing the use of less-invasive anesthetic techniques may limit postoperative complications and decrease the overall costs of EVAR.

Local anaesthesia for endovascular repair of infrarenal aortic aneurysms

OBJECTIVE

The study aimed to analyse and report the results of a 'local anaesthesia first' approach in elective endovascular aneurysm repair (EVAR) patients.

MATERIAL AND METHODS

Between January 2007 and August 2010, a total of 217 continuous patients (187 men, median age 76 years, range 52-94 years) underwent elective EVAR using this approach, with predefined exclusion criteria for local anaesthesia (LA). A retrospective analysis regarding technical feasibility, mortality, complication and endoleak rate was performed. The results are reported as an observational study.

RESULTS

LA was applied in 183 patients (84%), regional anaesthesia (RA) in nine patients (4%) and general anaesthesia (GA) in 25 patients (12%). Anaesthetic conversion from LA to GA was necessary in 14 patients (7.6%). Airway obstruction (n = 4) and persistent coughing (n = 3) were the most common causes for conversion to GA. Thirty-day mortality in the LA group was 2.7%, with 16/183 patients (8.7%) experiencing postoperative complications. All type I endoleaks (n = 5, 2.7%) occurred in patients with LA and challenging aneurysm morphologies.

CONCLUSIONS

A 'local anaesthesia first' strategy can successfully be applied in 75% of patients undergoing EVAR. The use of LA can impact imaging quality and thus precise endograft placement, which should be considered in patients with challenging aneurysm morphologies.

Anesthetic Experience With Endovascular Aortic Aneurysm Repair

Background: We endeavored to characterize the anesthesia experience with endovascular aneurysm repair (EVAR) at a large academic medical center in the United States. Methods: A retrospective review of electronic medical records was conducted for all patients undergoing elective EVAR from 2002 to 2007 in a large academic medical center. Results: A total of 522 cases met inclusion criteria, with 4% of cases using general anesthesia (GA), 92% regional anesthesia (RA), and 4% local anesthesia (LA). There was no statistically significant difference between the groups for duration of surgery or in-hospital mortality. In-hospital length of stay was longer for GA than LA or RA. Four cases were converted to open repair. Two mortalities occurred during the perioperative period (0.4% of cases). Conclusions: The vast majority of EVAR were successfully performed under RA, involved mild blood loss, involved infrequent need for conversion to GA, and resulted in brief in-hospital length of stay and low mortality rate.

Impact of the Type of Anesthesia on Outcome after Elective Endovascular Aortic Aneurysm Repair: Literature Review

The type of anesthesia used during aneurysm repair affects postoperative outcomes for the patient. Although endovascular aneurysm repair (EVAR) appears to improve surgical outcomes, by convention, general anesthesia remains predominantly used. The aim of this study was to compare the impact of the type of anesthesia (ie, locoregional versus general anesthesia) on the outcomes following EVAR. A literature search was carried out using the PubMed search engine to find relevant published articles that compared locoregional and general anesthesia in patients undergoing EVAR. The review of the selected studies showed that although patients in the locoregional group were less medically fit compared with those in the general anesthesia group, there was a reduction in the cardiovascular support required during and after the surgery, postoperative hospital stay, intensive care unit (ICU) stay, and postoperative mortality and morbidity. Although there is no level 1 evidence for or against locoregional anesthesia in EVAR, conventionally, EVAR has been performed under general anesthesia. But this is rooted in tradition rather than evidence. This review suggests that locoregional anesthesia can improve postoperative outcomes following EVAR by reducing hospital stay, ICU stay, mortality, and morbidity, although other factors may also have some influence.

Risk-Adapted Outcome After Endovascular Aortic Aneurysm Repair:Analysis of Anesthesia Types Based on EUROSTAR Data

PURPOSE

To compare anesthesia techniques in high-risk versus low-risk patients treated with endovascular aortic aneurysm repair (EVAR) with respect to outcomes.

METHODS

From July 1997 to August 2004, 5557 patients were enrolled in the EUROSTAR registry by 164 centers. Low-risk and high-risk patients were each divided into 3 groups according to anesthesia used during operation [general (GA), regional (RA), and local (LA)], resulting in 6 groups. Differences in preoperative and operative details among the 3 types of anesthesia were analyzed using a chi-square test for discrete variables and the Kruskal-Wallis test for continuous variables for each risk profile. Multivariate logistic regression analysis was performed on early complications.

RESULTS

Intensive care unit (ICU) admission was less frequent for high-LA (1.2% of patients) than high-RA (7.8%, p=0.0071) and high-GA (16.2%, p<0.0001), but high-RA still had a distinct advantage (p<0.0001) over high-GA. Systemic complications were lower both for high-LA (9.0%, p=0.0128) and for high-RA (10.7%, p<0.0001) than for high-GA (18.3%). Early death (< or =30 days) was reduced in high-RA (3.0%) versus high-GA (4.3%, p=0.0286).

CONCLUSION

On the basis of the EUROSTAR data, high-risk patients in particular attain important advantages from minimally invasive anesthetic techniques. Mortality, morbidity, hospital stay, and ICU admission are significantly lower for locoregional versus general anesthesia in the EUROSTAR registry. These results should encourage greater use of regional anesthesia in high-risk patients. Local anesthesia seems to be of similar benefit for EVAR in high-risk patients.

Influence of anesthesia type on outcome after endovascular aortic aneurysm repair: An analysis based on EUROSTAR data

BACKGROUND

Local and regional anesthesia was used in endovascular aortic aneurysm repair (EVAR) shortly after its introduction, and the feasibility has been documented several times. Nevertheless, locoregional anesthesia has not become accepted on a large scale, probably owing to a traditional surgical attitude preferring general anesthesia. This study compared various anesthesia techniques in patients treated with EVAR for infrarenal aortic aneurysms.

METHODS

From July 1997 to August 2004, 5557 patients who underwent EVAR repair in 164 centers were enrolled in the EUROSTAR registry. Data were compared among three groups: a general anesthesia group (GA-G) of 3848 patients (69%), a regional anesthesia group (RA-G) of 1399 patients (25%), and the local anesthesia group (LA-G) of 310 patients (6%). Differences in preoperative and operative details among the three study groups were analyzed using the chi(2) test for discrete variables and the Kruskal-Wallis test for continuous variables. Multivariate logistic regression analysis was performed on early complications.

RESULTS

The duration of the operation was reduced in the LA-G (115.7 +/- 42.2 minutes) compared with the RA-G (127.6 +/- 52.8 min, P < .0009) and GA-G (133.3 +/- 59.1 minutes, P < .0001). Admission to the intensive care unit was significantly less for LA-G patients (2%) than RA-G (8.3%, P = .0004) and GA-G (16.2%, P < .0001), but RA-G still had a distinct advantage (P < .0001) over GA-G. Hospital stay was significantly shorter in LA-G (3.7 +/- 3.1 days [P < .0001] vs GA-G [P = .007] vs RA-G), but RA-G (5.1 +/- 7.5 days) still had an advantage (P < .0001) vs GA-G (6.2 +/- 8.5 days). In EUROSTAR, systemic complications were significantly lower both for LA-G (6.6%, P = .0015) and RA-G (9.5%, P = .0007) than for GA-G (13.0%).

CONCLUSION

The EUROSTAR data indicate that patients appeared to benefit when a locoregional anesthetic technique was used for EVAR. Locoregional techniques should be used more often to enhance the perioperative advantage of EVAR in treating infrarenal aneurysms of the abdominal aorta.

Endovascular treatment of iliac artery aneurysms with a tubular stent-graft: mid-term results

OBJECTIVE

To report the mid term results of a prospective cohort of iliac artery aneurysms (IAAs) treated with endovascular tubular stent-grafts.

METHODS

All IAAs referred to the University Medical Center Groningen between June 1998 and June 2005 were evaluated for endovascular repair. Criteria for repair were a diameter of > or = 30 mm for anastomotic aneurysms and > or = 35 mm for true aneurysms. Preferentially, tubular grafts were used. Follow-up included both radiographs of the abdomen and duplex examination.

RESULTS

In 35 patients, 40 IAAs were treated endovascularly with a tubular stent-graft. Elective repair was performed in 30 patients (86%) and emergent repair in five patients (14%). Aneurysms were false in 26 cases (65%) and true in 14 cases (35%). Local anesthesia was used in 74% of the cases. The stent-grafts that were used included the Excluder contralateral limb (n = 28, 70%), Passager (n = 9, 22.5%), Hemobahn (n = 2, 5%), and Wallgraft (n = 1, 2.5%). The mean operation time was 83 +/- 28 minutes (range, 50 to 150 minutes). Mean hospital stay was 3.3 +/- 2.3 days (range, 1 to 12 days). There was no 30-day mortality. Patients were followed up for a mean of 31.2 +/- 20.7 months (range, 3 to 83 months). Complications occurred in two patients during follow-up, including migration with a proximal type I endoleak in one, and occlusion of the stent-graft in the other. The internal iliac artery was intentionally sacrificed in 28 patients (70%), and this led to gluteal claudication in three patients.

CONCLUSION

Endovascular repair of iliac artery aneurysms with flexible stent-grafts is a minimally invasive technique and is associated with low mortality and morbidity. Follow-up results up to 5 years suggest that the technique is durable. It should be regarded as a first choice treatment option for suitable aneurysms.