Endovascular Repair of Acute AAAs Under Local Anesthesia With Bifurcated Endografts:A Feasibility Study

Optimal perioperative medical management of the vascular surgery patient

Perioperative medical management of patients undergoing vascular surgery can be challenging because they represent the surgical population at highest risk. β-Blockers should be continued perioperatively in patients already taking them preoperatively. Statins may be used in the perioperative period in patients who are not on statin therapy preoperatively. Institutional guidelines should be used to guide insulin replacement. Recent research suggests that measurement of troponins may provide some risk stratification in clinically stable patients following vascular surgery. Multimodal pain therapy including nonopioid strategies is necessary to improve the efficacy of pain relief and decrease the risk of side effects and complications.

Anesthetic technique and acute kidney injury in endovascular abdominal aortic aneurysm repair

OBJECTIVE

Prior studies suggest that general anesthesia (GA) is associated with worse cardiopulmonary outcomes after endovascular abdominal aortic aneurysm repair (EVAR). Patients undergoing EVAR are at a high risk of developing perioperative acute kidney injury (AKI), and the relationship between anesthetic technique and AKI in these patients is not well-characterized. The authors sought to determine if anesthetic technique affected the risk of AKI in patients undergoing EVAR.

DESIGN

Retrospective, observational cohort study analyzed using a multivariate logistic regression model to assess the effects of anesthetic technique on renal outcome.

SETTING

Multiple institutions, mainly in North America.

PARTICIPANTS

Patients in the American College of Surgeons National Surgical Quality Improvement Program from 2005-2010 undergoing EVAR.

INTERVENTIONS

The authors investigated the association between anesthetic techniques, comparing GA to alternative (non-GA) techniques, and AKI.

MEASUREMENTS AND MAIN RESULTS

AKI was defined as an increase in the creatinine level of>2 mg/dL and/or dialysis. Of 13,026 patients, 84.4% underwent GA and 15.6% underwent non-GA techniques. AKI developed in 2.0% of the GA group and 1.4% of the non-GA group (unadjusted odds ratio [OR] 1.43, p = 0.075; adjusted OR [aOR] 1.00, p = 0.99). Risk factors for AKI include ASA class, ruptured aneurysm, preoperative renal dysfunction, symptomatic cardiovascular disease, and perioperative blood transfusion.

CONCLUSIONS

Anesthetic technique is not independently associated with the risk of AKI in patients undergoing EVAR.

Endovascular treatment of ruptured abdominal aortic aneurysms: aorto-uni-iliac or bifurcated endograft?

PURPOSE

This study evaluated the safety and technical and clinical success rates of positioning endovascular endografts (EG) in ruptured abdominal aneurysms.

MATERIALS AND METHODS

Patients with a ruptured abdominal aortic aneurysm confirmed by contrast-enhanced computed tomography angiography (CTA) were eligible for the analysis. Of 67 patients, 42 (62.7%) were treated with EG. Thirteen patients (30.9%) received an aorto-uni-iliac EG (group A) and 29 a bifurcated EG (group B). Patients were divided for comparative analysis according to the configuration of the EG implanted.

RESULTS

The primary technical success rate was 100%; the primary clinical success rate was 95% (40/42). There were two intraoperative deaths (4.7%) related to intractable shock. No patient required conversion to open repair. Overall, 12 patients (28.5%) died within 30 days. The in-hospital death rate was 30.9% (13/42). Hospital mortality rate was statistically higher in group A; the type of EG and intensive care unit admission were the only independent predictors of hospital mortality.

CONCLUSIONS

In our experience, a higher mortality rate was observed for the aorto-uni-iliac configuration; shock at admission was confirmed as the most important factor for postoperative survival.

Ischemic colitis complicating major vascular surgery

Ischemic colitis is a well-described complication of major vascular surgery, especially following open abdominal aortic aneurysm repair and endovascular aneurysm repair, but also with aortoiliac surgery, aortic dissection, and thoracic aneurysm repair. Following its onset, mortality remains high, highlighting the need for rapidly identifying the onset of symptoms and, perhaps more importantly, those patients at risk, in an attempt to prevent its onset. In this article, the authors review the causes, presentation, and diagnostic strategies of colonic ischemia. They also cover the operative management and outcomes for bowel resection and vascular repair. Finally, they evaluate some of the newer options for diagnosing this condition.

Incidence of colonic ischemia after repair of ruptured abdominal aortic aneurysm with endograft

BACKGROUND

Colonic ischemia after open repair of ruptured abdominal aortic aneurysm (rAAA) has been reported to be as high as 42% and is associated with high mortality rates when transmural necrosis is involved. With the evolution of endovascular aortic repair (EVAR) devices, some centers now primarily use this technique for rAAA. The objective of this study was to determine the incidence of colonic ischemia after EVAR of rAAA.

STUDY DESIGN

All patients who underwent EVAR of rAAA from January 2002 to January 2006 were included in this review. All flexible sigmoidoscopies were performed within 48 hours, ischemia was graded consistently, and treatment was initiated per protocol based on grade of ischemia. Patients with grades I and II ischemia were followed up with medical management and in some cases, repeat colonoscopy. All patients with grade III ischemia underwent bowel resection.

RESULTS

Forty-four patients underwent EVAR of rAAA during the study period. Operative mortality was 11%. Sigmoidoscopy was performed in 36 of 39 patients who survived longer than 24 hours. Bowel ischemia was documented in 8 of the 36 patients (23%). Of these, five had grade I or grade II ischemia at both initial and repeat endoscopy, so these patients did not progress to resection. Three patients underwent exploratory laparotomy with bowel resection because of grade III ischemia; one of these procedures was performed for worsening ischemia discovered at repeat colonoscopy.

CONCLUSIONS

This study demonstrated that the overall incidence of colonic ischemia (23%) after EVAR of rAAA is less than that reported for the open repair. We would continue to recommend mandatory flexible sigmoidoscopy for these patients.

Endovascular treatment for ruptured abdominal aortic aneurysm

BACKGROUND

An abdominal aortic aneurysm (AAA) (the pathological enlargement of the aorta) can develop in both men and women as they grow older. It is most commonly seen in men over the age of 65 years. Progressive aneurysm enlargement can lead to rupture and massive internal bleeding, a fatal event unless timely repair can be achieved. Despite improvements in perioperative care, mortality remains high (approximately 50%) after conventional open surgical repair. A newer minimally invasive technique, endovascular repair, has been shown to reduce early morbidity and mortality, as compared to conventional open surgery, for planned AAA repair. Emergency endovascular repair (eEVAR) has been used successfully to treat ruptured abdominal aortic aneurysm (RAAA), proving that it is feasible in selected patients. However, it is not yet known if eEVAR will lead to significant improvements in outcomes for these patients or indeed if it can replace conventional open repair as the preferred treatment for this lethal condition.

OBJECTIVES

To compare the advantages and disadvantages of eEVAR in comparison with conventional open surgical repair for the treatment of RAAA.

SEARCH STRATEGY

The Cochrane Peripheral Vascular Diseases Group searched their trials register (last searched October 2006) and the Cochrane Central Register of Controlled Trials (CENTRAL) database (last searched Issue 4, 2006). We searched a number of electronic databases and handsearched relevant journals until March 2006 to identify studies for inclusion.

SELECTION CRITERIA

Randomised controlled trials in which patients with a confirmed ruptured abdominal aortic aneurysm were randomly allocated to eEVAR, or conventional open surgical repair.

DATA COLLECTION AND ANALYSIS

Studies identified for potential inclusion were independently assessed for eligibility by at least two reviewers, with excluded studies further checked by the agreed arbitrators. As no randomised controlled trials were identified at present no tests of heterogeneity or sensitivity analysis were performed.

MAIN RESULTS

There were no randomised controlled trials identified at present comparing eEVAR with conventional open surgical repair for the treatment of RAAA.

AUTHORS' CONCLUSIONS

There is no high quality evidence to support the use of eEVAR in the treatment of RAAA. However, evidence from prospective controlled studies without randomisation, prospective studies, and retrospective case series suggest that eEVAR is feasible in selected patients, with outcomes comparable to best conventional open surgical repair for the treatment of RAAA . Furthermore, endovascular repair in selected patients may be associated with a trend towards reductions in blood loss, duration of intensive care treatment, and mortality.

Acute Abdominal Aortic Aneurysms: Cost Analysis of Endovascular Repair and Open Surgery in Hemodynamically Stable Patients with 1-year Follow-up

PURPOSE

To retrospectively assess the in-hospital and 1-year follow-up costs of endovascular aneurysm repair and conventional open surgery in patients with acute infrarenal abdominal aortic aneurysm (AAA) by using a resource-use approach.

MATERIALS AND METHODS

Institutional Review Board approval was obtained, and informed consent was waived. In-hospital costs for all consecutive patients (61 men, six women; mean age, 72.0 years) who underwent endovascular repair (n = 32) or open surgery (n = 35) for acute infrarenal AAA from January 1, 2001, to December 31, 2004, were assessed by using a resource-use approach. Patients who did not undergo computed tomography before the procedure were excluded from analysis. One-year follow-up costs were complete for 30 patients who underwent endovascular repair and for 34 patients who underwent open surgery. Costs were assessed from a health care perspective. Mean costs were calculated for each treatment group and were compared by using the Mann-Whitney U test (alpha = .05). The influence of clinical variables on the total in-hospital cost was investigated by using univariate and multivariate analyses. Costs were expressed in euros for the year 2003.

RESULTS

Sex, age, and comorbidity did not differ between treatment groups (P > .05). The mean total in-hospital costs were lower for patients who underwent endovascular repair than for those who underwent open surgery (euro20 767 vs euro35 470, respectively; P = .004). The total costs, including those for 1-year follow-up, were euro23 588 for patients who underwent endovascular repair and euro36 448 for those who underwent open surgery (P = .05). The results of multivariate analysis indicated that complications had a significant influence on total in-hospital cost; patients who had complications incurred total in-hospital costs that were 2.27 times higher than those for patients who had no complications.

CONCLUSION

Total in-hospital costs and total overall costs, which included 1-year follow-up costs, were lower in patients with acute AAA who underwent endovascular repair than in those who underwent open surgery.