Endovascular management of spinal vascular malformations

Spinal vascular malformations are rare diseases with a wide variety of neurological presentations. In this article, arteriovenous malformations (both from the fistulous and glomerular type) and spinal dural arteriovenous fistulae are described and an overview about their imaging features on magnetic resonance imaging (MRI) and digital subtraction angiography is given. Clinical differential diagnoses, the neurological symptomatology and the potential therapeutic approaches of these diseases which vary depending on the underlying pathology are given. Although MRI constitutes the diagnostic modality of first choice in suspected spinal vascular malformation, a definite diagnosis of the disease and therefore the choice of suited therapeutic approach rests on selective spinal angiography. Treatment in symptomatic patients offers an improvement in the prognosis. In most spinal vascular malformations, the endovascular approach is the method of first choice; in selected cases, a combined or surgical therapy may be considered.     

Viability of pancreatic transplants

28 consecutive organ donors were divided in 5 groups according to age (6 to 40, 40 to 65) shock and history of medication requiring hypertension. Electronmicroscopy, histology and immunohistochemistry of the exocrine and endocrine pancreatic tissue, of the ductal and vascular system revealed no abnormalities accept for donors with known hypertension. On the basis of these findings in the future we will remove pancreas from donors up to the age of 65 and from those having been in shock in order to meet the increasing demand for pancreas transplants.     

Surgical complications in 2000 renal transplants

Introduction

Renal transplantation is the best treatment for end-stage renal disease. In the last years, we have seen improvements in immunosuppressive treatment, which have allowed patients to experience a better quality of life and graft survival. Nevertheless, surgical complications remain important problems that increase morbidity, mortality, costs, and hospitalization. Our purpose was to evaluate surgical complications among a large series of 2000 renal transplantations.

Patients and Methods

We retrospectively analyzed all surgical complications among 2000 renal transplants performed between June 1980 and March 2010 in our department.

Results

Among 318 (15.9%) surgical complications, 4.8% of patients had urologic problems. Ureteral stenosis and fistula, stent obstruction, and ureteral necrosis occurred in 2.7%, 1.8%, 0.1%, and 0.2% of patients, respectively. Vascular complications reported in 2.7% of patients included arterial or venous thrombosis (1.0% or 0.4%), both arterial and venous thrombosis (0.1%), renal infarction (0.1%), renal artery aneurysm (0.1%) as well as arterial stenosis (0.5%), kinking (0.4%), or dissection (0.1%). Other complications, not specifically related with transplantation surgery, occurred in 4.4% of patients.

Conclusion

Renal transplantation is a safe surgery by experienced teams. Our rates of surgical complications were within those reported by other series. A meticulous surgical technique is mandatory to prevent them. Prompt diagnosis and management are required to prevent graft damage and patient morbidity.     

Prevention of vascular complications of diabetes by pancreatic islet transplantation.

Isolated pancreatic islets from Wistar-Lewis rats were transplanted into the liver of diabetic allogeneic recipients to assess ability to prevent diabetic renal and ophthalmic complications. At nine months, the diabetic animals without transplants showed significant increase in PAS-positive material in the renal glomerular mesangium and thickening of glomerular arterioles as compared with normal nondiabetic animals. New vessel formation was also significant in the retina and retinal capillary dilation. Animals in which diabetes had been corrected by early pancreatic islet transplantation were completely protected from these changes, showing no significant pathologic change when compared with normal animals.     

Endovascular treatment of aortic aneurysms in patients with renal transplants

Endovascular treatment of an abdominal aortic aneurysm was undertaken in two orthotopic renal transplant recipients with US Food and Drug Administration-approved aortic stents without specific measures taken to protect the transplanted kidney. Renal function remained unchanged in both patients. Follow-up imaging studies showed successful aneurysm exclusion. Endovascular abdominal aortic aneurysm treatment in renal transplant recipients does not appear to place the transplanted kidney at undue ischemic risk and may be the preferred approach in select patients.     

Heparin-induced thrombocytopenia. Practical management of vascular complications]

The authors report 23 cases of heparin-induced thrombocytopenia with vascular complications. The clinical presentation consisted of arterial ischaemia in 16 cases, hemiplegia in 1 case, 4 cases of blue thrombophlebitis, 1 case of bilateral thrombophlebitis, 1 case of pulmonary embolism. The vascular surgeon faced with such emergency complications must be aware of the difficulties of clinical (atypical forms) and laboratory diagnosis (unreliability of platelet aggregability tests). Arterial occlusions are generally accessible to treatment with a Fogarty catheter during an operation performed without the use of heparin. The excessively frequent delay in diagnosis explains the severity of these complications and 2 deaths, 1 case of paraplegia, 4 cases of amputation secondary to arterial occlusion, 4 cases of severe postphlebitis disease, including 2 cases requiring transmetatarsal amputation and one case of pulmonary sequelae after pulmonary embolism were observed in our series of 23 patients. The diagnosis of heparin-induced thrombocytopenia requires immediate discontinuation of heparin therapy. Replacement by low molecular weight heparin is not devoid or risks and can only be considered with a negative platelet aggregability test (in the presence of low molecular weight heparin). As these test can be rarely performed as an emergency procedure, the use of rapid-acting oral anticoagulants appears to be the most reliable solution. The place of platelet antiaggregants and partial interruption of the inferior vena cava is discussed.     

Urological complications in 350 consecutive renal transplants

Ten urological complications (2.9%) were found in 350 kidney transplants performed in this centre. These included obstructive uropathy (20%), urinary leaks (40%), distal uretic fistulas (necrosis) (30%) and renal calculi (10%). Two grafts were lost due to chronic rejection 9 and 30 months post-operatively. The remaining 8 patients have stable renal function (mean creatinine 1.5 mg%). It was concluded that meticulous surgical technique may reduce the number of urological complications and early diagnosis and prompt surgical treatment may help to save the grafts.     

Urological complications in 600 consecutive renal transplants

The results of 600 consecutive renal transplant operations (540 cadaver and 60 living related donor) in 491 patients were assessed with respect to urological complications. In nearly all cases the ureter was inserted into the bladder using a Leadbetter-Politano ureteroneocystostomy technique. The bladder was drained by Foley catheter for 5 days and the operation site by vacuum drain for a variable period. After 26 operations in 26 patients, 27 episodes of ureteric obstruction were identified (one reobstruction). These occurred between 1 day and 45 months after transplantation and involved the lowest third of the ureter 19 times, the middle third 3 times and the proximal third 4 times. They were due to stricture (11), pelvic collection (7), redundant or twisted ureter (3) or other cause (5). An anatomical predisposing factor in either patient or graft was identified in 31 per cent of these caes. After 18 operations in 18 patients, 21 episodes of urine leakage were identified (three re-leakages). These occurred between 1 day and 6 months after transplantation and an anatomical predisposing factor in either patient or graft was present in 59 per cent. Thus, overall, 7 per cent of patients developed a urological complication in this series. This rate has declined in recent years in parallel with a general reduction in steroid dose for immunosuppression. This last feature, combined with the surgical technique described, has resulted in a low incidence of urological complication after transplantation, being now between 1 and 2 per cent.     

Prevention and management of polytetrafluoroethylene graft complications in peripheral vascular reconstruction

The use of expanded PTFE grafts as a vascular substitute has been well established. PTFE is an acceptable alternative for patients in whom the saphenous vein is unusable. Nonreinforced PTFE grafts do a better job of resisting infection, permitting cellular ingrowth, and allowing the development of a true neointima. During a 6 year period ending in April 1981, 129 grafts were placed in various positions. Most of these were placed primarily in the femoropopliteal position. One death occurred as a direct result of the surgery. Only two infections were encountered, both were delayed and patient-induced.There were no true aneurysms in the PTFE grafts of our patients. The use of smooth noncrushing clamps applied gently with just enough pressure to stop blood flow will lessen the likelihood of aneurysmal formation. Careful surgical technique can minimize problems. False aneurysm in vascular reconstruction can largely be prevented by the proper establishment of hemostasis at the suture line. Selection of an appropriate needle and suture along with the use of proper technique in their placement will help provide the best possible results. One should follow the curve of the needle at the time of suturing to help prevent elongation of the suture holes, which may contribute to difficulties in establishing hemostasis at the suture line. Thrombosis is the most common problem associated with the use of this graft: correction requires careful balloon catheter techniques. Salvage of the graft can be obtained by endarterectomy, patch grafting, or jump grafts so that the entire prosthesis does not have to be replaced.