Atheroembolization and potential air embolization during aortic declamping in open repair of a pararenal aortic aneurysm: A case report.

INTRODUCTION: When ischemic events ascribable to microembolization occur during open repair of proximal abdominal aortic aneurysms, a likely origin of atheroembolism is not always found. PRESENTATION OF CASE: A 78-year old man with enlargement of the entire aorta underwent open repair for a pararenal abdominal aortic aneurysm using supraceliac aortic clamping for 20min. Then the graft was clamped, the supraceliac clamp was removed, and the distal and right renal anastomoses were also completed. The patient was stable throughout the operation with only transient drop in blood pressure on reperfusion. Postoperatively the patient developed ischemia, attributable to microembolization, in legs, small intestine, gall bladder and kidneys. He underwent fasciotomy, small bowel and gall bladder resections. Intestinal absorptive function did not recover adequately and he died after 4 months. Microscopic examination of hundreds of intestinal, juxtaintestinal mesenteric, and gall bladder arteries showed a few ones containing cholesterol emboli. DISCUSSION: It is unsure whether a few occluded small arteries out of several hundred could have caused the ischemic injury alone. There had been only moderate backbleeding from aortic branches above the proximal anastomosis while it was sutured. Inadvertently, remaining air in the graft, aorta, and aortic branches may have been whipped into the pulsating blood, resulting in air microbubbles, when the aortic clamp was removed. CONCLUSION: Although both atheromatous particles and air microbubbles are well-known causes of iatrogenic microembolization, the importance of air microembolization in open repair of pararenal aortic aneurysms is not known and need to be studied.

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.

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 vascular occlusion by rapid reverse phase polymer: a preliminary in vitro study of retrograde injection.

During vascular surgical operations, there is a need for a simpler and more reliable method of temporary arterial occlusion than those currently employed, especially of heavily calcified arteries. A thermosensitive polymer, LeGoo (LG) (Pluromed, Woburn, MA), has been used successfully for temporary vascular occlusion. It has hitherto been injected by a cannula that has been introduced into the artery to be occluded, here henceforth called the "cannulation method." Injection into arterial ostia without cannulation, using an injection device that arrests blood flow during the injection, here henceforth called "a retrograde method" may enable temporary hemostasis when ostial stenoses render it impossible to inject LG using the cannulation method. The objective of the present study was to study the feasibility of a retrograde method and to compare it with the cannulation method in an in vitro model, incorporating a narrow orifice to simulate ostial stenosis, using tap water at 37°C instead of blood. The retrograde method of LG injection, using a modified paediatric Foley catheter, turned out to be feasible to produce a durable LG plug more reliably, at higher water pressure and with less deep LG injection than with the cannulation method.

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.

Treatment of major vein injury with the hemostatic fleece TachoSil by interposing a peritoneal patch to avoid vein thrombosis: A feasibility study in pigs.

BACKGROUND: Vein lacerations in awkward locations are difficult to repair and carry high mortality. The hemostatic fleece, TachoSil, is effective in preventing intraoperative bleeding in different settings, but has not been recommended for use in large vein injury. TachoSil with a peritoneal patch interposed to avoid vein thrombosis has been reported as a method to obtain hemostasis in vein laceration, but further studies of this method are needed. MATERIALS AND METHODS: A 1.5 × 1 cm defect was created in the vena cava in five pigs. A 26 × 32 mm peritoneal patch was applied on the coagulant side of a 48 × 48 mm TachoSil sheet, and used to cover the defect. Light compression with a wet sponge was applied for 3 min. No vascular suturing was performed. RESULTS: Successful hemostasis was obtained in four out of the five pigs although the minimum TachoSil gluing zone surrounding the peritoneal patch was only 0-2 mm. The fifth pig died of hemorrhage 30 min after surgery due to a 4-mm stretch with no TachoSil gluing zone outside the peritoneal patch. At six days postoperatively the peritoneal patch was well integrated into the vein wall. After 28 days, the peritoneal patch was almost indiscernible from surrounding vein endothelium. CONCLUSIONS: Vein wall defects can be repaired using TachoSil with a peritoneal patch interposed to prevent contact between the thrombogenic TachoSil sheet and the vein lumen. An adequate TachoSil gluing zone all around the patch is essential.

Effective Hemostasis in Severe Mesenteric Vein Laceration with Tachosil(®), using a Low- or Non-thrombogenic Patch to Prevent Tachosil(®)-induced Thrombosis.

Fibrinogen- and thrombin-coated collagen fleece (FTCC) facilitates surgical hemostasis, and is of particular value during resection of parenchymatous organs. Since thrombosis may ensue if the preparation is unintentionally applied intravascularly, it has not been recommended for treating lacerations of large veins, and no previous reports describe its use in vein repair. Our observations in two patients suggest, however, that FTCC might be indicated for hemostasis in vein injury where vascular suture is difficult or not possible, provided a low- or non-thrombogenic patch is interposed to prevent FTCC-induced vein thrombosis. Our two patients had severe lacerations of the proximal superior mesenteric vein (SMV) not amenable to conventional vein repair. Rapid hemostasis was obtained without suturing using Tachosil(®), an FTCC preparation, covered with omentum. In the first patient hemostasis was obtained at the expense of vein thrombosis, apparently due to contact between the coagulant-containing side of Tachosil(®) and the inside of the vein wall. In our second patient we therefore put a small patch of parietal peritoneum on the section of the Tachosil(®) targeted to cover the vein tear to avoid direct contact between Tachosil(®) and the vein lumen. Ultrasound examination 3 days postoperatively, and autopsy 11.5 months later showed that the vein was widely patent with no stenosis or thrombus. Our observations in these two patients were that an FTCC-omentum pack alone secured rapid hemostasis in severe SMV laceration, and when a peritoneal patch was interposed between FTCC and a lacerated SMV, FTCC-induced vein thrombosis did not occur.

Pseudoaneurysm of the abdominal aorta due to a needle-like osteophyte on the first lumbar vertebra.

A 46-year-old woman was admitted with acute abdominal pain radiating to the back. Computed tomography examinations showed a needle-thin perforation of the aorta, opposite the origin of the superior mesenteric artery, with a pseudoaneurysm. A needle-sharp spinal osteophyte was located exactly opposite the perforation. There was no sign of infection, and the perforation seemed to have been caused by the osteophyte. This aortic perforation occurred without any major trauma, but repeated minor occupational trauma to her abdomen may have played an etiologic role. The pseudoaneurysm and adjacent aorta were exposed through a thoracolaparotomy. The aortic wall was normal, with good tensile strength; therefore, the perforation in the aortic wall was sutured with a double vascular suture, and the osteophyte was resected. To our knowledge, aortic perforation due to a vertebral osteophyte in the absence of major trauma has not previously been described.

Treatment of a hepatic artery aneurysm by endovascular stent-grafting.

Aneurysms of the visceral arteries are rare. Traditional treatment has been surgical or endovascular with coil embolization. Recently, however, reports on endovascular therapy with stent-grafts have been published. We report the case of a 61-year-old man who was successfully treated with a stent-graft for a symptomatic combined celiac/hepatic artery aneurysm.

Complications associated with the Angio-Seal arterial puncture closing device: intra-arterial deployment and occlusion by dissected plaque.

The Angio-Seal arterial closure device is widely used to prevent bleeding and facilitate early ambulation after arterial puncture. We had referred to us three female patients in whom this device had been used; its sponge had been unintentionally deployed in the arterial lumen. In a fourth female patient, a dissected plaque underneath the device occluded the femoral artery. Severe lower extremity ischemia occurred in each case. One intraluminal sponge was detected only after 20 days, when the patient had developed severe symptoms due to microembolization; in another patient, ischemia occurred 9 days after intraluminal deployment. In two, or possibly three, of the cases, the superficial femoral artery had been punctured. The device should not be used when the superficial femoral artery has been punctured, in which case complications are more likely to occur. Lower limb ischemia within several months after deployment of these devices should be investigated with duplex ultrasound scanning to examine the possibility that the ischemia may be caused by the device or by device-related thrombus. It is important to register the use of such devices in the procedural reports to make it possible to link their use to eventual later ischemic events.

Flow measurement before and after papaverine injection in above-knee prosthetic femoropopliteal bypass.

OBJECTIVE: To investigate the value of intraoperative blood flow measurements on early and long-term patency of above-knee prosthetic femoropopliteal bypass. METHODS: Flow was measured with a transit time flowmeter before (basal flow) and after an intragraft injection of papaverine (papaverine flow) in 87 operations (86 patients) between January 1990 and December 2001. Sixty-one grafts were of polyester, and 26 were of polytetrafluoroethylene. The operations were done under epidural anesthesia. The preoperative angiographic run-off score and clinical risk factors were recorded. Patency rates were analyzed with the product limit method and compared with the log-rank test. Variables found to be near significantly related to patency rates (P < .1) were included in a multivariate analysis performed with the Cox proportional hazard model. RESULTS: Basal flow measurements were not related to patency. The 2- and 5-year patency rates for grafts with a papaverine flow < or = 500 mL/min were 48% and 18% compared with 66% and 52% for grafts with a papaverine flow > or = 500 mL/min. These differences were statistically significant (P = .012, hazard ratio, 2.6). Two- and 5-year patency rates for smokers vs nonsmokers were 44% and 18% vs 69% and 54%. The patency rates for patients with poor vs good run-off were 42% and 27% vs 66% and 31%. Smoking (P = .008, hazard ratio, 2.75) and poor run-off score (P = .009, hazard ratio, 2.38) were found to be independent risk factors for reduced patency rates. Poor run-off score did not correlate with low values of measured basal or papaverine flow. CONCLUSIONS: Papaverine flow of < or = 500 mL/min is associated with reduced mid- and long-term patency rates. Additional antithrombotic medication and frequent follow-up for these grafts should be considered. The inferior patency rates of smokers and patients with poor run-off indicate that prosthetic bypass is less suitable for these groups of patients.

[Use of stents in abdominal aortic aneurysms]. / Bruk av stentgraft ved abdominale aortaaneurismer.

BACKGROUND: Endovascular treatment of aortic aneurysms has acquired a widespread application. We present the results of endovascular treatment of infrarenal, abdominal aortic aneurysms in our hospital from 1995 through 2002. MATERIAL AND METHOD: Seventy-one stent graft procedures were performed on 69 patients (64 men), mean age 72 years (range 48-96 years). Mean aneurysm diameter was 57 mm (range 35-100 mm). Sixty-nine procedures were elective and two were emergency procedures. All data were registered prospectively. RESULTS: Two procedures failed initially because of technical problems. Both patients underwent a successful procedure later. Immediate conversion to open surgery was done in one case because of a collapse of the graft into the aneurysm sac. There was no 30-day mortality for elective procedures. The conversion rate after a mean observation time of 42 months was 11%. Late complications resulted in 47 re-interventions in 29 patients, of which 96% were done in cases treated with Stentor or Vanguard prostheses. CONCLUSION: Endovascular treatment of aortic aneurysms is an alternative to open surgery. Stent graft failure can be serious and difficult to predict. This treatment should not be recommended to patients younger than 70 years and fit for open surgery.