Reducing morbidity of thoracoabdominal aneurysm repair by preliminary axillofemoral bypass

Staged open surgery for bicuspid aortic valve regurgitation and coarctation of the aorta in a Jehovah's witness

Background

Jehovah’s Witnesses refuse allogeneic blood transfusions, which makes cardiovascular surgery challenging. Surgeons must minimize blood and fluid loss within one procedure.

Case presentation

We herein describe a 17-year-old male Jehovah’s Witness with bicuspid aortic valve regurgitation and coarctation of the aorta. The procedures were performed in the following order: aortic valve replacement combined with Nick’s aortic root enlargement, right axillary artery–bilateral external iliac artery bypass, and distal arch–descending aorta bypass.

Conclusions

Axillary artery–bilateral external iliac artery bypass maintained distal perfusion and reduced the amount of heparin during distal arch–descending aorta bypass surgery.

Extending resuscitative endovascular balloon occlusion of the aorta: Endovascular variable aortic control in a lethal model of hemorrhagic shock

BACKGROUND

The duration of use and efficacy of resuscitative endovascular balloon occlusion of the aorta (REBOA) is limited by distal ischemia. We developed a hybrid endovascular-extracorporeal circuit variable aortic control (VAC) device to extend REBOA duration in a lethal model of hemorrhagic shock to serve as an experimental surrogate to further the development of endovascular VAC (EVAC) technologies.

METHODS

Nine Yorkshire-cross swine were anesthetized, instrumented, splenectomized, and subjected to 30% liver amputation. Following a short period of uncontrolled hemorrhage, REBOA was instituted for 20 minutes. Automated variable occlusion in response to changes in proximal mean arterial pressure was applied for the remaining 70 minutes of the intervention phase using the automated extracorporeal circuit. Damage-control surgery and whole blood resuscitation then occurred, and the animals were monitored for a total of 6 hours.

RESULTS

Seven animals survived the initial surgical preparation. After 20 minutes of complete REBOA, regulated flow was initiated through the extracorporeal circuit to simulate VAC and provide perfusion to distal tissue beds during the 90-minute intervention phase. Two animals required circuit occlusion for salvage, while five animals tolerated sustained, escalating restoration of distal blood flow before surgical hemorrhage control. Animals tolerating distal flow had preserved renal function, maintained proximal blood pressure, and rapidly weaned from complete REBOA.

CONCLUSION

We combined a novel automated, extracorporeal circuit with complete REBOA to achieve EVAC in a swine model of uncontrolled hemorrhage. Our approach regulated proximal aortic pressure, alleviated supranormal values above the balloon, and provided controlled distal aortic perfusion that reduced ischemia without inducing intolerable bleeding. This experimental model serves as a temporary surrogate to guide future EVAC catheter designs that may provide transformational approaches to hemorrhagic shock.

Bypass Techniques for Descending Thoracic Aortic Surgery

The conduct of partial left heart bypass or partial car diopulmonary bypass (CPB) during surgery involving the descending thoracic aorta or thoracoabdominal aorta is one of the most unappreciated and misunder stood extracorporeal circulation procedures in cardio vascular surgery. It is different from conventional CPB, and although some uninitiated practitioners consider it simpler, it is in fact more complicated than conven tional CPB and involves different concepts. It requires expertise and skill in regulating the flow, pressure, and oxygenation of blood going to both the proximal and distal parts of the body and management of the special bypass or shunt procedures used, specialized monitor ing, and knowledge about the protection and preserva tion of organs both proximal and distal to the aortic clamping. It demands exquisite communication and un derstanding of the unique problems faced by the sur geon, anesthesiologist, and perfusionist.

Passive Temporary Visceral Shunt from the Axillar Artery as an Adjunct Method during the Open Treatment of Thoracoabdominal Aortic Aneurysm

BACKGROUND

Distal aortic retrograde perfusion systems like the left heart bypass or femoro-femoral extracorporeal circulation are the methods of reference for organ protection during direct approaches to thoracoabdominal aortic aneurysms. The aim of this work was to evaluate the use of a passive arterial shunt to reduce visceral ischemia during aortic operations when occlusive diseases of the iliac arteries make distal aortic retrograde perfusion inappropriate.

METHODS

Ten patients affected by a Crawford type III thoracoabdominal aneurysm (TAA) were operated on between January 2013 and January 2015 with the use of a temporary shunt inserted onto the left axillar artery that allows visceral perfusion immediately after the aorta is opened. The operation was performed after a single dose of heparin (50 UI/kg). The sera lactate levels were measured 2 hr after the last aortic clamp was removed and compared with those obtained from a group of 19 patients operated on for a Crawford type IV TAA during the same period without any arterial shunt.

RESULTS

Neither mortality nor paraplegia occurred. The sera lactate levels were lower in the group of patients operated on for a type III TAA (2.57 ± 1) than for a type IV TAA (3.68 ± 1) (P < 0.01, Student's t-test).

CONCLUSION

This method was effective for low mesenteric ischemia, easy to perform, and did not require high doses of anticoagulants.

Proximal endovascular blood flow shunt for thoracoabdominal aortic aneurism without total aortic clamping

The authors present a surgical approach to type III and IV Crawford aneurysms that does not need total aortic clamping, which allows the more objective prevention of direct ischemic damage, as well as its exclusion by the endoprosthesis implantation, shunting the flow to the synthetic graft.

Temporary extracorporeal axillo-iliac vascular prosthesis shunt in open repair of a pararenal aortic aneurysm

INTRODUCTION

When a long aortic clamp time is expected or when upper body to lower body collateral arteries are sparse, temporary lower body perfusion may be needed to reduce ischemic injury during supraceliac clamping in open repair of pararenal aortic aneurysms. The use of conventional extracorporeal perfusion techniques carry extra risks and is not in the armamentarium of most vascular surgeons. An axillo-femoral or -iliac shunt using a vascular prosthesis does not require the same degree of anticoagulation and causes less activation of blood components.

PRESENTATION OF CASE

A patient, who had extensive vascular stenotic disease and large bowel ischemia, was operated on for a pararenal aortic aneurysm while the lower body was perfused via a temporary extracorporeal vascular prosthesis axillo-iliac shunt. Copious backbleeding encountered while suturing the proximal anastomosis testified to the efficacy of the temporary shunt. A left hemicolectomy had to be performed for gangrene of the sigmoid colon and he needed 2 days of respiratory support; otherwise the postoperative course was uneventful.

DISCUSSION

In our case more ischemic injury than that observed might have been expected without the temporary bypass but significant backbleeding may have negated some of the beneficial effect of the shunt.

CONCLUSION

A temporary axillo-femoral or -iliac shunt prevents lower limb ischemia and provides an ample amount of collateral blood flow to the torso. It does not need to be buried subcutaneously as previously described. Occlusive balloons should be used where possible to prevent backbleeding and to further increase available collateral blood supply.

Novel Visceral-Anastomosis-First Approach in Open Repair of a Ruptured Type 2 Thoracoabdominal Aortic Aneurysm: Causes behind a Mortal Outcome

Case reports to analyze causes and possible prevention of complications in a new setting are important. We present an open repair of a ruptured type 2 thoracoabdominal aortic aneurysm in a 78-year-old man. Lower-body perfusion through a temporary extracorporeal axillobifemoral arterial prosthesis shunt was combined with the use of a branch to the permanent aortic prosthesis to enable rapid visceral revascularization using a visceral-anastomosis-first approach. The patient died due to transfusion-induced capillary leak syndrome and left colon necrosis; the latter was probably caused by a combination of back-bleeding from lumbar arteries causing a steal effect, an accidental shunt obstruction, and hemodynamic instability towards the end of the operation. The visceral-anastomosis-first approach did not contribute to the complications. This approach reduces the time when visceral organs are perfused only via collateral arteries to the time needed for suturing the visceral anastomoses. This may be important when collateral perfusion is marginal.

Temporary extracorporeal brachio-femoral vascular prosthesis shunt for ischemia prevention in an operation for abdominal aortic and iliac aneurysms in a patient with Marfan's syndrome

In open vascular repair, when prolonged infrarenal aortic clamping can be expected, and collateral perfusion is reduced, the use of a temporary shunt may reduce the risk of ischemic complications. In a patient with Marfan's syndrome and aortic dissection who had developed infrarenal aneurysms, segmental arteries had been occluded by prior aortic surgery and collateral arteries in the anterior torso could have been damaged by previous pectus excavatum, muscle flap, sternotomy, and ventral hernia operations. The axillary artery was dilated. For the prevention of ischemia during open repair with a bifurcated graft, a temporary extracorporeal brachio-femoral vascular prosthesis shunt was constructed. Ischemia was not observed. The use of a temporary extracorporeal brachio-femoral shunt with a vascular prosthesis is a feasible method for ischemia prevention.

Novel extra-anatomic intra-abdominal reconstruction for treatment of paravisceral aortic infection

Adequate treatment of native or prosthetic aortic infection requires extensive surgical debridement and establishing flow to the extremities using extra-anatomic or in situ reconstruction, each with its inherent limitations. Infection of the paravisceral aortic segment precludes an axillofemoral bypass as the sole treatment because of inability to provide visceral perfusion. In situ autograft or allograft reconstructions could be limited by conduit availability or significantly prolonged operative time, or both. Placement of an antibiotic-soaked prosthetic in a field with gross purulence carries a high risk of reinfection. We describe a technique for extra-anatomic, intra-abdominal reconstruction using an antibiotic-soaked prosthetic graft to avoid the infected paravisceral aortic bed and achieve antegrade lower extremity and visceral vessel perfusion.

Operation for an infected thoracoabdominal aneurysm in a patient previously treated with an axillobifemoral bypass for an infected abdominal aortic prosthesis: a case report

High operative mortality of infected thoracoabdominal aortic aneurysms (ITAA) is partly attributable to ischemic injury during aortic clamping. A case is presented of an 88-year old man who was admitted with imminent rupture of an ITAA. Axillobifemoral bypass grafting had been performed after removal of an infected abdominal aortic prosthesis six years earlier. In situ graft replacement was performed during 70 minutes of aortic clamping just below the pulmonary hilum without causing any but transient renal ischemic injury. Since the infrarenal aorta was absent after previous removal of an infected aortic prosthesis, the axillobifemoral bypass provided sufficient blood supply to intestines, kidneys and spinal medulla via arterial collaterals. Blood supply was sufficient, although a previous rectosigmoid resection must have destroyed some of the collaterals and one iliac artery was chronically occluded. The most important message from this case is that an axillobifemoral bypass may prevent ischemic injury during operations for ITAA even when collateral circulation is reduced, possibly on the condition that backbleeding from end-organ arteries is prevented, and there is a pressurized aortic segment that can redistribute blood that arrives via arterial collaterals.

Open surgical repair and endovascular treatment in adult coarctation of the aorta

BACKGROUND

The aim of this study was to compare the results of endovascular therapy (covered stenting) with surgical technique to repair aortic coarctation in adults.

METHODS

A prospective study of 11 patients who were treated during the past 10 years was carried out. Of these, five patients underwent endoprosthesis (group A) and six an open surgical repair (group B). Follow-up comprised monitoring of the blood pressure, echocardiography, and computed tomography and magnetic resonance angiographic studies.

RESULTS

The mean age of the patients was 46 years (range: 17-67 years) and the mean follow-up was 52.6 months (range: 1-117 months; 32.3 for group A vs. 69.7 for group B; p = 0.01). Two cases in group A were recoarctations after child angioplasty. The rate of postoperative complications was 27.7% (one hemothorax for group A vs. one pneumothorax and one hemothorax for group B); however, mortality did not occur. The success rate of the endovascular technique was 80%. The stay in the intensive care unit was 2.3 days with significant differences (one group A vs. three group B; p = 0.01), whereas length of hospital stay was 11 days (7.8 group A vs. 11.83 group B; p = 0.17). The pressure gradient across the stenosis decreased by 21.9 ± 3.7 mm Hg (24.5 ± 4.3 group A vs. 33 ± 3.2 group B). Six patients (54.5%) showed persistent hypertension (80% group A vs. 33% group B), with a mean residual pressure gradient of 23.4 ± 4.3 mm Hg (22.5 ± 5.4 group A vs. 22 ± 2.1 group B; p = 0.58).

CONCLUSIONS

Short- and medium-term results of the endovascular therapy are similar, with shorter stay in the intensive care unit and higher necessity of antihypertensive treatment. Echocardiography and Doppler aortic coarctation gradients slightly higher than 20 mm Hg are usual during follow-up.

Emergency Abdominal Aortic Aneurysm Repair in a Patient with Failing Heart: Axillofemoral Bypass Using a Centrifugal Pump Combined with Levosimendan for Inotropic Support

We describe the case of an 83-year-old patient requiring repair of a large symptomatic abdominal aortic aneurysm (AAA). The patient was known to have coronary artery disease (CAD) with symptoms and signs of significant myocardial dysfunction, left-heart failure, and severe aortic insufficiency. The procedure was performed with the help of both mechanical and pharmacological circulatory support. Distal perfusion was provided by an axillofemoral bypass with a centrifugal pump, with dobutamine and levosimendan administered as pharmacological inotropic support. The patient's hemodynamic status was monitored with continuous cardiac output monitoring and transesophageal echocardiography. No serious circulatory complications were recorded during the perioperative and postoperative periods. This paper suggests a potential novel approach to combined circulatory support in patients with heart failure, scheduled for open abdominal aortic aneurysm repair.

Staged repair for a chronic dissecting thoracic aortic aneurysm with no transfusion in a Jehovah's Witness patient

We present the case of a 59-year-old male Jehovah's Witness who underwent staged repair for a thoracic aortic aneurysm with no transfusion. The primary operation to replace the distal portion of the aortic arch and left subclavian artery reconstruction were performed. We applied axilla femoral artery temporary external bypass. A second operation was carried out 8 months later. We replaced the descending aorta and reconstructed the intercostal arteries under temporary bypass in the same manner as was done during the previous operation. The blood losses and minimum hemoglobin values during the two operations were 2235 and 13,941 ml, respectively, 8.8 and 5.9 g/dl, respectively. Administration of erythropoietin and a drainage blood recovery device were useful. Surgical repair for a thoracic aortic aneurysm using a temporary bypass is thus considered a viable surgical option in such situations and is important for conducting effective perioperative management.

Femoro-femoral partial bypass in the treatment of thoracoabdominal aneurysms

This article describes our rationale for the use of femoro-femoral bypass as a primary modality for perfusion in the repair of thoracoabdominal aortic aneurysms at Stanford University School of Medicine. Benefits and limitations of this method are discussed and compared with other described techniques.

The use of an aortoiliac side-arm conduit to maintain distal perfusion during thoracoabdominal aortic aneurysm repair

Thoracoabdominal aneurysm repair continues to be associated with a significant risk of operative complications, many of which are related to the prolonged period of aortic cross clamping inherent in the procedure. A variety of adjuvant techniques have been used in attempts to decrease morbidity, including atriofemoral extracorporal bypass, subarachnoid drainage, epidural cooling, and preliminary axillofemoral bypass. Herein is described a method to maintain distal perfusion with a side-arm conduit, originating from the most proximal aspect of the aortic graft and terminating on the left iliac artery. The technique has the potential to minimize hemodynamic instability while decreasing the period of pelvic and lower extremity ischemia and simplifying reattachment of aortic branch vessels. This method provides another option that can be considered in these technically demanding operative procedures.

Emergency repair of thoracoabdominal aortic aneurysms with immediate presentation

OBJECTIVE

The objective of this report was the study of the clinical outcome of emergently repaired thoracoabdominal aortic aneurysms (TAAAs).

METHODS

We retrospectively reviewed our experience with TAAA repairs from 1990 to 1998. During this interval, 110 TAAA procedures were performed, 33 (30%) of which were for immediate presentations. The chi(2) test and regression analysis were used for the analysis of mortality, paraplegia, and renal failure (hemodialysis) rates and of factors that predict these complications, respectively.

RESULTS

There were no significant differences between the elective and immediate presentations with respect to the use of adjunctive procedures (lumbar drain, hypothermia, and bypass grafting). The overall mortality rate was 13%. There were no statistically significant differences between the 30-day mortality rates or the complication rates in elective versus immediate presentations. Subgroup analysis results showed a significantly higher in-hospital mortality rate in type II TAAA with immediate presentation and free rupture presentation as compared with the overall mortality rate (50% vs 13%, P <.05, and 67% vs 13%, P <.01, respectively). Multiple regression analysis results identified the use of bypass grafting (atrial-femoral or cardiopulmonary) and lumbar drain and shorter bypass grafting time as significant predictors of decreased overall mortality (P <.05). The mortality rates were not significantly different among aneurysm types and were not significantly decreased with the use of hypothermia. Paraplegia (5%) and renal failure (9%) rates were not predicted with aneurysm type, immediate versus elective presentation, or the adjunctive use of hypothermia, lumbar drain, or bypass grafting.

CONCLUSION

The emergency repair of TAAA with immediate presentation can be performed with mortality and morbidity rates that approach those of elective presentations, except in the setting of free rupture or symptomatic type II TAAA. Adjunctive circulatory management techniques and lumbar drains may reduce mortality in TAAA repair.

A modified technique of atriofemoral bypass for visceral and distal aortic perfusion in thoracoabdominal aortic surgery

Modified atriofemoral bypass (AFB) was used for repair of thoracoabdominal aortic aneurysms (TAAA). The primary circuit consisted of a centrifugal pump and heat exchanger to perfuse and warm the systemic circulation. A parallel secondary circuit with a second heat exchanger perfused the viscera with cold blood. A progressive sequential cross-clamping technique was used. This technique offers theoretical hemodynamic and metabolic advantages and may prove to be useful in preventing ischemic and reperfusion injury to the spinal cord and kidneys.

Prevention of spinal cord ischaemic complications after thoracoabdominal aortic surgery

Since the publication of prior reviews on this topic, substantial clinical experience with a variety of operative strategies to prevent ischaemic cord complications has been reported. The available data on angiographic localisation of critical intercostal vessels, and, in particular, the evoked potential response to cross-clamping in patients indicates that risk of paraplegia varies considerably even among patients with equivalent TAA extent. Factors such as individual development of the ASA, patent critical intercostals, and the particulars of collateral circulation when intercostal aortic ostia are already occluded likely account for this variability. Information available from SSEP monitoring relative to the dynamic course of cord ischaemia with cross-clamping, and the parallel, if not, frustrating experience with angiographic localisation and intercostal vessel reconstruction indicates that a narrow temporal threshold of cord ischaemia with clamping is present in many patients. This reinforces the importance of both expeditious clamp intervals, critical intercostal re-anastomoses, and the desirability of neuroprotective manoeuvres during cross-clamp induced cord ischemia. As suggested in compelling experimental work our contemporary clinical experience, and predicted by prior reviewers, regional cord hypothermia provides significant promise for limiting or eliminating, in particular, immediate perioperative deficits. Avoidance of postoperative hypotension, spinal cord oedema, and preservation of critical intercostal vessels are additional strategies necessary to impact the development of delayed deficits favourably.

Improvement in results of repair of type IV thoracoabdominal aortic aneurysms

PURPOSE

Although management of extensive type I and II thoracoabdominal aortic aneurysms (TAA) remains a formidable challenge, results of repair of TAA originating in the distal thoracic aorta (type IV) appear to have improved significantly. To quantitate this perceived improvement, the following retrospective study was undertaken to examine the results of type IV TAA repair at the Brigham & Women's Hospital over the past 18-year period.

METHODS

From July 1977 to September 1994, nonruptured atherosclerotic type IV TAAs were repaired in 58 patients. The mean age was 70 years, and associated risk factors included smoking (91%), hypertension (86%), coronary artery disease (52%), and previous aortic surgery (38%). Mean follow-up was 2.4 years (median 2 years).

RESULTS

Overall 30-day mortality was 5.3% (two deaths). Morbidity included stroke (3.5%), paraplegia (1.8%), permanent paraparesis (1.8%), myocardial infarction (7%), pneumonia (8.8%), gastrointestinal bleeding (11%), intestinal ischemia (5.3%), wound infection (7.0%), peripheral ischemia (5.3%), in-hospital dialysis (8.8%), and permanent dialysis (1.9%). Overall 5-year survival was 50%. With univariate analysis, survival was positively correlated with more recent year of operation (p = 0.002), smaller volume of intraoperative blood transfusion (p = 0.02), decreased supraceliac ischemia time (p = 0.04), and the use of the retroperitoneal approach (p = 0.09). Multiple regression analysis revealed that the year of operation was the only independent predictor of survival (p = 0.003). Subgroup analysis of patients who underwent operation between 1977 and 1987 (n = 13) and 1988 and 1994 (n = 45) revealed statistically significant improvements in length of hospital stay (46 +/- 12 vs 21 +/- 4 days, p = 0.02), postoperative dysrhythmia (50% vs 16%, p = 0.03), postoperative maximum serum glutamic oxaloacetic-transaminase (516 +/- 234 vs 319 +/- 139 mg%, p = 0.04), incidence of hemorrhage requiring reexploration (33% vs 0%, p = 0.002), 30-day mortality (23% vs 0%, p = 0.009), and in-hospital mortality (39% vs 2.2%, p = 0.002).

CONCLUSIONS

The modern mortality, morbidity, and survival of surgical repair of type IV TAA in our institution approaches that of infrarenal abdominal aortic aneurysm.