Techniques in occluding the aorta during endovascular repair of ruptured abdominal aortic aneurysms

Technical challenges during emergent endovascular aneurysm repair with the ALTO system

INTRODUCTION

Ruptured abdominal aortic aneurysms (AAAs) pose an immediate threat for patient's life and endovascular repair (EVAR) is currently the preferred treatment modality in the presence of suitable anatomy. This is determined based on the requirements of each endograft as described in the instructions for use (IFU). The new ALTO system (Endologix, Irvin, CA, U.S.A.), can accommodate a great range of anatomies such as short necks and/or narrow access, but its unique design requires specific technical modifications during treatment of ruptured AAAs.

AREAS COVERED

The standard double balloon technique has long been described and it is used to provide circulatory support during EVAR for ruptured AAA. While this technique is straightforward with the use of endografts with a traditional design, this would not be the case if one uses the ALTO system. In that case specific maneuvers would be required to treat AAA patients in an acute setting.

EXPERT OPINION

The ALTO system although being able to treat AAAs with adverse anatomy, it may not be appropriate during treatment of ruptured AAA patients with profound hemodynamic instability. A careful evaluation of the individual's patient anatomy and hemodynamic condition is mandatory in order to decide the best endograft for each case.

Modern management of ruptured abdominal aortic aneurysm

Ruptured abdominal aortic aneurysms (rAAA) remain one of the most clinically challenging and technically complex emergencies in contemporary vascular surgery practice. Over the past 30 years, a variety of changes surrounding the treatment of rAAA have evolved including improvements in diagnosis, development of coordinated referral networks to transfer patients more efficiently to higher volume centers, deliberate de-escalation of pre-hospital resuscitation, modification of patient and procedure selection, implementation of clinical pathways, as well as enhanced awareness of certain high-impact postoperative complications. Despite these advances, current postoperative outcomes remain sobering since morbidity and mortality rates ranging from 25%-50% persist among modern published series. Some of the most impactful variation in rAAA management has been fostered by the rapid proliferation of endovascular repair (EVAR) along with service alignment at selected centers to improve timely revascularization. Indeed, clinical care pathways and emergency response networks are now increasingly utilized which has led to improved outcomes contemporaneously. Moreover, evolution in pre- and post-operative physiologic resuscitation has also contributed to observed improvements in rAAA outcomes. Due to different developments in care provision over time, the purpose of this review is to describe the modern management of rAAA, while providing historical perspectives on patient, procedure and systems-based practice elements that have evolved care delivery paradigms in this complex group of patients.

Coeliac artery avulsion secondary to high velocity blunt abdominal trauma: a case report

Coeliac artery (CA) injuries are an extremely rare subset of blunt abdominal trauma with a reported incidence of only 0.01%. Patterns of CA injury include intimal tear, dissection, thrombosis and pseudoaneurysm, with the most rare being complete CA avulsion. These complex injuries pose a treatment challenge due to rapid blood loss and anatomical difficultly in achieving proximal and multiple points of distal vascular control. To our knowledge, this case of CA avulsion from blunt polytrauma is only the 7th case reported in the literature. To assist in management, we report a case of blunt traumatic CA avulsion managed successfully with open ligation following endovascular balloon occlusion of the juxta-coeliac aorta for haemorrhage control.

Endovascular balloon occlusion is associated with reduced intraoperative mortality of unstable patients with ruptured abdominal aortic aneurysm but fails to improve other outcomes

BACKGROUND

Proximal aortic control by endovascular balloon occlusion (EBO) is an alternative to conventional aortic cross-clamping (CAC) in hemodynamically unstable patients presenting with a ruptured abdominal aortic aneurysm (rAAA). The aim of this study was to evaluate the potential clinical benefit of EBO over CAC.

METHODS

Data from 72 patients with rAAA treated at our institution from 2001 to 2013 were retrospectively analyzed. All patients were hemodynamically unstable (mean arterial blood pressure at admission <65 mm Hg or associated unconsciousness, cardiac arrest, or emergency endotracheal intubation). Clinical end points of hemodynamic restoration, mortality rate, and major postoperative complications were assessed for CAC (group 1) and EBO (group 2).

RESULTS

At admission, 72 patients were unstable. CAC was performed in 40 and EBO in 32. Intraoperative mortality was 43% in group 1 vs 19% in group 2 (P = .031). In group 1, the approach for CAC (thoracotomy [n = 23] vs laparotomy [n = 17]) did not influence intraoperative mortality (43% vs 41%). There was no significant difference in 30-day (75% vs 62%) and in-hospital (77% vs 69%) mortality rates between groups. After EBO, the treatment-open vs endovascular repair-did not influence the intraoperative mortality rate (31% vs 43%; P = .5). Eight surgical complications were secondary to CAC (1 vena cava injury, 3 left renal vein injuries, 1 left renal artery injury, 1 pancreaticoduodenal vein injury, and 2 splenectomies), but no EBO-related complication was noted (P = .04). Differences in colon ischemia (15% vs 28%) and renal failure (12% vs 9%) were not statistically significant. Abdominal compartment syndrome occurred in four patients in group 2 and in no patients in group 1.

CONCLUSIONS

Compared with CAC, EBO is a feasible and valuable strategy and is associated with reduced intraoperative mortality of unstable rAAA patients, but not in-hospital mortality, in this retrospective study.

Endovascular versus open repair of ruptured abdominal aortic aneurysms

Although major improvement has occurred to make elective repair of abdominal aortic aneurysms a safe procedure, the incidence of ruptured abdominal aortic aneurysms and mortality rates are still disappointing. Endovascular abdominal aortic aneurysm repair has produced quantum changes in aneurysm treatment. The successful application of the endovascular approach for the treatment of abdominal aortic aneurysms in the elective setting has prompted a strong interest regarding its possible use in dealing with the long-standing challenge of a ruptured abdominal aortic aneurysm. Since the first report, several centers have reported results and a wide spectrum of opinion regarding its application, with special consideration to logistical and practical barriers for appropriate utilization. The purpose of this article is to review all the available literature on the endovascular repair of ruptured abdominal aortic aneurysms and to analyze the most recent trends in their management, with special consideration given to comparing results of conventional and endovascular approaches.

The use of rapid endovascular balloon occlusion in unstable patients with ruptured abdominal aortic aneurysm

OBJECTIVE

: To present our results and demonstrate advantages of rapid endovascular balloon occlusion (REBO) of the juxtarenal aorta in unstable patients with ruptured abdominal aortic aneurysm (rAAA).

METHODS

: Since 2006, all unstable patients with rAAA are immediately transferred to the operating room (OR). No computed tomography scan is performed once diagnosis is made on ultrasound examination. Instability is defined as systolic blood pressure less than 60 mm Hg, unconsciousness, cardiac ischemia, or intubation. Once arrived in the OR, a Reliant aortic balloon is introduced and inflated at the level of the renal arteries. Subsequently, an angiogram is made through the contralateral femoral artery in order to decide between open or endovascular repair (EVAR).

RESULTS

: Twelve patients with rAAA were defined as unstable. REBO was installed within 10 minutes after arrival in the OR. Aortic occlusion resulted in immediate hemodynamic stability. Five patients were suitable for EVAR. Seven patients had open repair. For these abdominal dissection was more careful since no instability was encountered. All patients survived the procedure except one. Mean stay on intensive care unit was 19.7 days for open group and 8.4 for EVAR.

CONCLUSIONS

: REBO of the juxtarenal abdominal aorta by pc technique in unstable patients with rAAA resulted in a 17% 30-day mortality and a 100% 1-year event-free follow-up for survivors. With this technique, EVAR exclusion is still a valuable treatment. Exposure and decision making for the open group is easier to perform with less risk for additional damaging to neighboring structures during dissection since urgent cross-clamping is not necessary.

Use of aortic balloon occlusion to decrease blood loss during sacral tumor resection

BACKGROUND

Aortic balloon occlusion has been introduced into sacral tumor surgery to reduce extensive hemorrhage. The purposes of this retrospective study were to determine the efficacy of aortic balloon occlusion in decreasing intraoperative and postoperative blood losses and to analyze the complications of this technique.

METHODS

The cases of 215 patients in whom a sacral tumor had been treated surgically between 1997 and 2009 were studied retrospectively. Ninety-five patients who had had sacral tumor resection without aortic balloon occlusion were compared with 120 patients in whom aortic balloon occlusion had been carried out during the tumor resection. The demographic data, possible factors influencing hemorrhage, and total blood loss volume (including intraoperative and postoperative volumes) were determined with a review of the medical records and compared between the two groups.

RESULTS

There were no significant differences between the two groups in terms of the demographic data, grade of malignancy, tumor blood supply, location of the tumor, percentage of patients who had a recurrent tumor or preoperative radiation, surgical approach, or type of resection. The patients with aortic balloon occlusion had a larger mean tumor volume, more frequently had a sacral reconstruction, and had a longer mean operative time; however, their mean total (2963 mL) and intraoperative (2236 mL) blood loss volumes were lower than those of the patients without occlusion (4337 and 3935 mL, respectively) (p < 0.001). Complications related to aortic balloon occlusion included femoral artery embolism in three patients and hematoma formation at the puncture site in five.

CONCLUSIONS

Aortic balloon occlusion decreases the total and intraoperative blood loss volumes in patients treated with sacral tumor surgery who require extensive dissection. There is a low rate of balloon-related complications.

Resuscitation for an octogenarian with ruptured abdominal aortic aneurysm using endovascular balloon

Ruptured abdominal aortic aneurysm is a true emergency for emergency physicians and surgeons. Achieving effective proximal control may ameliorate further hemodynamic deterioration and buy time for patients awaiting further repair. An 82-year-old man was referred to our hospital with shock resulting from a ruptured abdominal aortic aneurysm. At the moment of impending cardiac arrest, aortic occlusion was achieved with a transfemoral endovascular balloon, without fluoroscopic guidance. The octogenarian then underwent a prosthetic graft reconstruction and recovered well. In this report, the safeguards and pitfalls of aortic occlusion using an endovascular balloon are discussed. This procedure is not only effective in vascular control but also valuable in resuscitation.

Repair of ruptured abdominal aortic aneurysms by endovascular techniques

Emergency EVR for ruptured AAA is now technically feasible, and several reports with small numbers have appeared in the literature from major centers suggesting that the results may be the same as or better than seen with open repair. The immediate priority is avoidance of over-resuscitation together with the rapid transfer of the patient to CT and then to the operating theater. Because of the learning curve involved, these cases should be attempted only by major centers that have extensive elective endovascular experience. The requirement for 24-hour availability of surgeons and radiologists trained in endovascular techniques places an enormous strain on vascular and radiologic staff and is achievable only in major centers with large teams of doctors. These issues raise important questions about the delivery of vascular services and whether all cases of ruptured aortic aneurysm should be transferred to major vascular centers. The operating theater staff and other support persons need training in endovascular techniques and in rapid deployment of an aortic occlusion balloon. A wide selection of devices, guidewires, and catheters must be immediately available in the operating theater. The ideal way to establish the role of EVR for ruptured AAA would be a randomized trial, but there might be logistic difficulties in recruiting sufficient numbers in major vascular centers, particularly as screening for AAA becomes more common and reduces the number of cases. There also are ethical issues as to whether these patients can give informed consent for involvement in such a trial. The alternative is for major centers to continue to develop their endovascular programs, to do more cases, and to compare the results with historical controls undergoing open repair.