Incidence of pancreas graft thrombosis using low-molecular-weight heparin

Abstract: Introduction: Simultaneous pancreas–kidney transplantation is the current treatment of choice for patients with type I diabetes and end stage renal disease. Vascular graft thrombosis (VGT) after pancreas transplantation is the main cause of early graft loss. Methods: A total of 188 consecutive pancreas transplantations were performed between January 2000 and December 2006. A retrospective study was carried out in order to compare incidence of VGT and relaparotomy‐for‐bleeding rate of once daily fixed dose low‐molecular‐weight‐heparin (LMWH) to dose‐adjusted intravenous unfractionated heparin (UFH). Results: Fifty‐eight patients receiving LMWH and 129 receiving UFH were identified. There were 7% (4/58) VGTs in the LMWH and 17% (22/129) in the UFH group (p = 0.047). The frequency of major bleeding requiring relaparatomy was not significantly different in the groups related to LMWH and UFH, respectively (6.9% vs. 7.8%). One yr patient and pancreas graft survival was 98.9/89.6% in the LMWH and 97.8/74.4% in the UFH group. Donor and recipient characteristics were similar. Conclusion: In our experience once daily fixed dose LMWH might not be inferior to dose‐adjusted intravenous heparin in preventing pancreas graft thrombosis.     

Extra-intracranial anastomosis using a venous graft

Summary The authors describe a patient with ischaemic neurological incidents due to bilateral hypoplasia of the carotids. Because the use of the superficial temporal artery or the occipital artery was impossible, the extra-intracranial anastomosis was performed by a direct venous graft between the external carotid artery and the posterior temporal artery. The authors describe and illustrate the operation, emphasizing the particular difficulties due to differences in diameter of the arteries and the graft. Because postoperative control angiography demonstrated perfect permeability of the anastomosis, this technique is suggested for when a normal branch of sufficient diameter of the external carotid artery cannot be used.     

静脉移植和吻合掌侧静脉在不同平面末节断指再植中的应用

目的 探讨不同平面末节断指的再植方法.方法 2004-2007年,对63例71指末节断指,按损伤部位分为4区,采用静脉移植和吻合掌侧静脉的方法进行再植.结果 术后71指存活70指.随访时间为3个月至3年,再植手指饱满,手指长度正常,指甲外观满意.再植指两点分辨觉平均为6.5 mm,除Ⅳ区关节融合者外,其余拇指指间关节与远侧指问关节活动度平均为69°.结论 对末节断指的处理,为保留手指长度和指甲,血管移植修复是必要的,尤其是Ⅱ区和Ⅲ区,同时行掌侧静脉吻合对末节再植的成功至关重要.     

Urothelial carcinogenesis and portocaval anastomosis in the rat

Summary Portacaval anastomoses were performed in the rat to study urothelial carcinogenesis in this model and the promoting effect of dietary tryptophan. We were unable to produce any urothelial cancers or premalignant changes; some animals formed uric acid stones and developed papillary hyperplasia in the bladder. We conclude that the initiating carcinogen is likely to be exogenous and may be dietary in those experiments that have produced urothelial cancers.     

Incidence of pre-operative deep venous thrombosis in abdominal surgery

In order to determine the incidence of pre-operative and postoperative deep venous thrombosis (DVT) in patients not receiving prophylactic anticoagulant therapy, bilateral phlebography was performed in a prospective study pre-operatively and on the 9th postoperative day, in 51 consecutive patients submitted for major abdominal surgery. The presence of a DVT before surgery was demonstrated in 15.7 per cent of the patients. This high frequency confirms objectively the rationale of starting prophylactic anticoagulant therapy before the surgical procedure. Thrombi were demonstrated postoperatively by phlebography in 54.9 per cent of the patients. Thus the true incidence of DVT induced by surgery was 39.2 per cent taking into account the 15.7 per cent pre-operative DVT rate.     

Successful endoluminal thrombo-aspiration of renal graft venous thrombosis

Renal transplant vein thrombosis is an unusual event occuring in 0.3–3 % of renal transplantations. Prognosis is uniformly poor with graft loss in nearly every case. We report here the first three cases of renal graft vein thrombosis successfully treated by percutaneous endoluminal thromboaspiration. After an initially uneventful course all recipients developed anuria and required hemodialysis. In two cases, an ultrasound examination suggested a diagnosis of venous thrombosis. Emergency arteriography and phlebography were performed, confirming the complete thrombosis of the graft veins. Thromboaspiration was carried out with full heparinization and led to renal function improvement in all cases. Grafts are still functioning 6 months after the procedure, with serum creatinine levels of 176 μmol/l, 120 μmol/l and 184 μmol/l, respectively. Thus, this procedure avoids surgical and anaesthetic risks and allows, if performed at an early stage, restoration of graft function. Great care must be taken to avoid vein wall damage, vascular suture line rupture, or pulmonary embolism. Received: 15 March 1999/Revised: 26 November 1999/Accepted: 30 November 1999     

Incidence of graft rejection after pancreas and kidney transplantation]

The possibility of an immunological follow-up of the pancreas through the renal transplant after simultaneous pancreaticorenal transplantation (S.P.R.T.) is controversial. Fifty patients have received a neopren-injected extraperitoneal segmental pancreatic transplant and a contralateral renal transplant, after immunological preparation with blood transfusions, without tissue matching but with a negative anti-T lymphocyte cross-match. Immunosuppression consisted in a three- or four-drug therapy during the first 10 days, then a long-term two-drug therapy (ciclosporine and azathioprine). Sixteen rejection episodes were noted in 16 patients during the first 3 postoperative months. No concomitant alteration of the pancreatic function occurred (no pancreatic histology). No isolated pancreatic rejection has been noted so far. One patients presented with 2 episodes of simultaneous rejection 15 and 26 months after transplantation. The actuarial survival rate at 2 years of the patients, kidneys and pancreata respectively is 96%, 92% and 80%. The absence of long-term alteration of the pancreatic function probably proves the absence of undetected pancreatic rejection. In our experience, the follow-up of the renal function allows screening and treating rejection episodes before a possible functional alteration of the pancreatic transplant occurs. In our opinion, extraperitoneal segmental pancreatic transplantation, a simple procedure with satisfactory metabolic results in the long term, is a good technique for S.P.R.T.     

Postoperative deep venous thrombosis in Japan. Incidence and prophylaxis

The incidence of postoperative deep venous thrombosis was investigated using the iodine-125-fibrinogen method in 256 patients undergoing major surgery. Deep venous thrombosis was found in 49 patients (15.3 percent), and nonfatal pulmonary embolism developed in one of seven patients in whom the thrombus extended to the popliteal vein. The same investigation was performed in 110 patients who wore a graduated compression stocking on one leg, with the other leg serving as a control. Deep venous thrombosis was found in 4 of 110 stockinged legs (3.6 percent) and in 16 of 110 control legs (14.5 percent). The incidence of deep venous thrombosis decreased significantly in patients who wore the stocking. An increase in femoral venous flow velocity was found in the stockinged legs by the Doppler method. The mean velocity of venous return by xenon-133 clearance was significantly greater in the stockinged legs than in the control legs. These findings were considered to support the efficacy of graduated compression stockings for the prevention of deep venous thrombosis.     

供体抗原经门静脉处理及移植物从门静脉回流对大鼠胰腺移植物功能存活的影响

以35只雄性SD大鼠为受体，制成糖尿病模型，以同龄Wistar雄性大鼠为供体，行全胰腺移植。供体抗原分别经门静脉或周围静脉处理，处理时间分别为移植前预处理或移植时处理，移植物静脉分别从门静脉或下腔静脉回流，结果表明供体抗原经门静脉预处理及移植物从门静脉回流对胰腺移植物功能存活的延长具有协同效应，移植时处理延长胰腺移植物效果不如移植前预处理，但可能具有一定的实用意义。     

Incidence and propagation of infrageniculate deep venous thrombosis in trauma patients

BACKGROUND: The incidence and propagation of thrombosis involving vessels distal to the popliteal vein has not been clearly defined in trauma patients. Our aim was to determine the incidence and rate of propagation of infrageniculate deep venous thrombosis (DVT) in a trauma population and identify potential risk factors specific to propagation. METHODS: Retrospective review of all trauma admissions between the years 2001 and 2003 was conducted. Only those 18 years or older with an isolated infrageniculate DVT who underwent a lower extremity venous duplex scan during admission were included in the study. Nature of injury, injury severity score (ISS), method of DVT prophylaxis, thrombus location, and risk factors for hypercoagulable states were recorded. RESULTS: During the study period, 698 trauma admissions were included, and 109 (15.7%) with infrageniculate DVT were identified. Thirty-nine (35.7%) had thrombus propagation (14 suprageniculate and 25 infrageniculate) with a mean ISS of 27.6. Seventy (64.3%) had infrageniculate DVT without propagation and a mean ISS of 19.6. Thirty-eight (97%) patients with propagating infrageniculate DVT had received mechanical prophylaxis, and 33 (84%) also received chemical prophylaxis. The 14 patients with suprageniculate thrombus propagation were the most severely injured (mean ISS = 35.1). Elevated ISS, operation, age < or =62 years, and intensive care unit admission were positively correlated with propagation of infrageniculate DVT. CONCLUSION: The incidence and propagation of infrageniculate DVT in an aggressively prophylaxed trauma population are greater than previously reported. The clinical significance of isolated infrageniculate DVT remains to be determined, but when associated with a multiple injury trauma, the patient may be at risk for future suprageniculate DVT formation and may benefit from therapeutic anticoagulation.     

Ruptured 'fem-pop' vein graft presenting as deep venous thrombosis

The public is becoming increasingly aware of the symptoms of deep vein thrombosis (DVT) due to the so-called 'economy class' syndrome. However, arterial rupture can mimic these symptoms. We report of a misdiagnosis of a ruptured 'fem-pop' vein graft (previously unreported) presenting identically as a DVT. The patient received conventional anticoagulation treatment which could have resulted in disastrous consequences.     

Successful surgical salvage of pancreas allografts after complete venous thrombosis

BACKGROUND: Complete venous thrombosis of the pancreas after simultaneous pancreas-kidney (SPK) transplantation usually results in graft loss. We describe a technique that allows salvage of the graft after complete venous thrombosis. METHODS: A total of 150 patients with insulin dependent diabetes mellitus/end stage renal disease underwent SPK over the past decade at the University of Miami. Of these, three patients developed complete venous thrombosis after induction therapy with antiinterleukin-2R antibody and i.v. tacrolimus. These three patients underwent surgical thrombectomy followed by heparinization and oral anticoagulation. The splenic vein was opened distally at the tail of the pancreas and the superior mesenteric vein at the level of the mesentery or head of the pancreas. Thrombectomy was performed with a Fogarty catheter. The portal anastomosis was not opened or manipulated. The arterial "Y" graft was not clamped and the right iliac vein was controlled proximally with a double wrapped vessel-loop to contain possible thrombus. In one patient, the partially thrombosed splenic artery was opened at the tail of the pancreas and thrombectomy was performed in the same fashion. There were no apparent technical problems. A pancreatic biopsy was not performed, nor was acute rejection treated empirically. RESULTS: Intraoperative and serial Doppler ultrasound showed good flow through the allograft. In all three patients the exocrine and endocrine function of the pancreas was preserved with a mean follow-up of 15 months. CONCLUSIONS: The described surgical thrombectomy followed by systemic anticoagulation may be useful in the salvage of the allograft pancreas in case of complete venous thrombosis.     

Treatment and outcome of pancreatic venous graft thrombosis after kidney--pancreas transplantation

BACKGROUND: Pancreas venous graft thrombosis after transplantation is the main non-immunological cause of graft failure and usually results in pancreatectomy. Duplex Doppler ultrasonography is the primary imaging technique for monitoring vascular patency after pancreas transplantation. This study reports the results of rescue treatments for pancreas graft thrombosis after simultaneous pancreas--kidney transplantation. METHODS: One hundred and ninety-six patients with insulin-dependent diabetes mellitus received a simultaneous pancreas--kidney transplantation. Venous graft thrombosis was diagnosed in 25 of these patients based on Doppler ultrasonographic findings. RESULTS: Total venous graft thrombosis was diagnosed in 20 symptomatic patients, of whom 14 required graft pancreatectomy. Surgical thrombectomy was attempted in six patients with preserved arterial supply and was successful in four. Partial venous graft thrombosis was diagnosed in five asymptomatic patients; one also had partial splenic artery thrombosis. Rescue graft procedures included systemic anticoagulation (one patient), arterial thrombolysis (one) and venous thrombolysis and/or mechanical venous thrombectomy (four episodes in three patients). Graft rescue was achieved in three patients treated by venous thrombolysis/thrombectomy. CONCLUSION: Doppler ultrasonography allows the appropriate selection of rescue treatment based on the findings of total or partial thrombosis.     

Analysis of nonpenetrating clips versus sutures for arterial venous graft anastomosis

The use of nonpenetrating clips (NPC) for vascular anastomosis is quickly becoming accepted. Studies attest to decreased anastomotic time, comparable patency rates, and decreased blood loss. Few human studies on the use of NPC have been done to date. The purpose of this study was to evaluate primary patency rates, operative time, and complications associated with NPC compared to those with standard sutures for arterial venous graft (AVG). We retrospectively reviewed the clinical course of 82 patients with a mean age of 45 years (range, 22 to 87) from February 1996 to July 1999. All patients underwent upper extremity AVG construction. The procedures were performed at a single institution, by a single, well-experienced surgeon who has extensive experience with NPC. Primary patency rates, operative time, and complications were analyzed. Overall thrombotic incidence of AVG when NPC were used (27/48, 56%) was similar to that of sutures (17/34, 50%). Thrombotic incidence within the first year was similar as well (23/48, 48% and 13/34, 38%). The mean time to primary thrombosis was similar in both groups (6.9 and 6.8 months). The operative time required to construct an AVG with NPC (83 min) was significantly less than that with sutures (96 min) (p = 0.015). There was no significant difference in incidence of graft infection or pseudoaneurysm formation. NPC for AVG reduced operative time and resulted in primary patency and complication rates similar to those associated with use of sutures. The mean time to primary thrombosis was similar for both groups. Our findings suggest an intimai hyperplastic response of a similar nature resulting in thrombosis of both NPC and sutured AVGs. Presented at the Twenty-fifth Annual Meeting of the Peripheral Vascular Surgery Society, Toronto, Ontario, Canada, June 10, 2000.