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41.
42.
Many publications discuss the various strategies for vascular reconstruction (VR) in pediatric LDLT. Having knowledge of alternative techniques is helpful in planning transplants. This article presents three case reports that illustrate some of the alternative techniques for HV, PV, and HA reconstruction in pediatric LDLT. It also reviews the available alternative strategies reported for VR in pediatric LDLT. In the first case, a 13‐month‐old girl presented a PRETEXT III HB with invasion of the retrohepatic vena cava. An LLS graft HV was anastomosed to a DD iliac vein graft and subsequently implanted in a “standard” fashion in the recipient. In the second case, a 44‐month‐old boy presented with multifocal HB and portomesenteric thrombosis and the portal inflow was done through a renoportal anastomosis. In the third case, a 22‐month‐old child with a failed Kasai procedure had extensive HA thrombosis. The HA reconstruction was performed with an interposition of the recipient's IMV graft. The use of alternative techniques for VR in pediatric LDLT is paramount to the success of such a complex procedure. Imaging studies can help transplant surgeons outline surgical strategies and define the best technique to be used in each case.  相似文献   
43.
The association between LT and gastrectomy is not common. Only two studies reported the gastrectomy/LT association in children. Here, we report three children who underwent LT who required a concomitant or sequential gastrectomy for different reasons. Patient 1, a 16‐yr‐old boy, during the LT, underwent a partial gastrectomy due to extensive injury to the duodenum. He had a previous and unusual portoenterostomy performed in the duodenum. Bowel reconstruction was performed using an intestinal loop that was first used for the bilio‐enteric anastomosis and then connected to the gastric stump. Patient 2, a 22‐month‐old female child, underwent a partial gastrectomy with a Roux‐en‐Y reconstruction during a retransplantation. She had a large perforated gastric ulcer blocked by the allograft liver. Patient 3, a 26‐month‐old male child, five yr after living donor LT, was submitted to a partial gastrectomy because of gastric outlet obstruction. The histopathology was compatible with eosinophilic gastritis. The association between LT and gastrectomy in the pediatric population is extremely rare. Appropriate knowledge of the previous transplantation technique is very important. Further studies are required to assess the outcomes of the different types of gastric reconstruction in pediatric recipients.  相似文献   
44.
BACKGROUND: Polymyxin B (PMX-B) is a polycationic antibiotic, known to bind the lipid A portion of endotoxin, a cell wall component found exclusively in gram negative bacteria (GNB). An extracorporeal hemoperfusion device (TORAYMYXIN) has been developed: PMX is covalently bound on the surface of an insoluble carrier material so that the endotoxin can be inactivated in the blood without exerting its toxicity on the brain and kidney. The aim of this study was to clarify the efficacy, safety and clinical effects of direct hemoperfusion with an immobilized polymyxin-B fiber column (DHP-PMX) in solid organ transplanted patients with severe sepsis or septic shock. METHODS: From June 2004 to May 2005, 15 patients (10 men and 5 women), mean age 55 years old (46-65 range), underwent kidney or liver transplantation and developed severe sepsis or septic shock, as defined by the Consensus Conference of American College Physicians/Society of Critical Care Medicine (ACCP/SCCM) criteria. GNB were detected in all the patients receiving conventional treatments including antibiotic therapy, vasopressive or inotropic agents, and ventilation support. The DHP-PMX treatment was performed three times in each patient. Hemodynamic and respiratory parameters, dosage of vasopressor/inotropic drugs were assessed at baseline and after each treatment. RESULTS: No adverse events occurred. From baseline to 3rd treatment, mean arterial pressure (MAP) was increased (from 63+/-5 to 83+/-4 mmHg), while the dosage of dobutamine (from 7.5+/-3 to 3+/-2 mcg/kg/min) and noradrenaline (from 1.3+/-0.45 to 0.05+/-0.02 mcg/kg/min) were reduced. The PaO2/FiO2 ratio increased (from 234+/-38.47 to 290+/-107.48 mmHg). CONCLUSION: The use of DHP-PMX in association with conventional therapy may be an important aid in patients with sepsis.  相似文献   
45.
Rats of the Milan hypertensive strain (MHS) are resistant to both hypertensive and diabetic renal disease. Genetically determined hypertrophy of intrarenal arteries has been suggested as the putative mechanism preventing transmission of systemic hypertension to the glomerular microcirculation or diabetes-induced loss of autoregulation, which lead to glomerular hypertension and consequent podocyte injury and proteinuria. This study aimed to investigate glomerular barrier function and structure in ageing and diabetic MHS rats under basal conditions and after injection of 2.5 g of bovine serum albumin (BSA) causing increased workload and possibly removing haemodynamic protection by inducing renal cortical vasodilatation. Genetically related rats of the Milan normotensive strain (MNS) served as a proteinuric counterpart. No change in renal function or structure was detected in diabetic MHS rats, whereas MNS rats developed diabetic nephropathy superimposed on that occurring spontaneously in this strain. Diabetic, but not non-diabetic, MHS rats showed significantly reduced synaptopodin and nephrin expression, though to a lesser extent than non-diabetic and diabetic MNS rats, together with unchanged podocyte number, density and structure and no proteinuria. Agrin expression was significantly altered in diabetic versus non-diabetic MHS animals, whereas collagen I was expressed only in diabetic MHS rats and collagen IV content did not change significantly between the two groups. Upon BSA injection, proteinuria increased markedly and abundant BSA was detected only in kidneys from diabetic MHS rats. BSA injection was associated with changes in intrarenal arteries suggesting vasodilatation, without any influx of inflammatory cells. These data indicate that while MNS rats show marked changes in the glomerular filtration barrier with either age or diabetes, glomerulosclerosis-resistant MHS rats develop only minor diabetes-induced podocyte (and extracellular matrix) alterations, which are not associated with proteinuria unless they are unmasked by an increased workload or removal of the haemodynamic protection.  相似文献   
46.
47.
Activation of mitochondrial ATP-sensitive potassium (KATP) channels is postulated as an effective mechanism to confer cardio and neuroprotection, especially in situations associated to oxidative stress. Pharmacological activation of these channels inhibits glia-mediated neuroinflammation. In this way, diazoxide, an old-known mitochondrial KATP channel opener, has been proposed as an effective and safe treatment for different neurodegenerative diseases, demonstrating efficacy in different animal models, including the experimental autoimmune encephalomyelitis (EAE), an animal model for Multiple Sclerosis. Although neuroprotection and modulation of glial reactivity could alone explain the positive effects of diazoxide administration in EAE mice, little is known of its effects on the immune system and the autoimmune reaction that triggers the EAE pathology. The aim of the present work was to study the effects of diazoxide in autoimmune key processes related with EAE, such as antigen presentation and lymphocyte activation and proliferation. Results show that, although diazoxide treatment inhibited in vitro and ex-vivo lymphocyte proliferation from whole splenocytes it had no effect in isolated CD4+ T cells. In any case, treatment had no impact in lymphocyte activation. Diazoxide can also slightly decrease CD83, CD80, CD86 and major histocompatibility complex class II expression in cultured dendritic cells, demonstrating a possible role in modulating antigen presentation. Taken together, our results indicate that diazoxide treatment attenuates autoimmune encephalomyelitis pathology without immunosuppressive effect.  相似文献   
48.
Independent lung ventilation (ILV) is a ventilation strategy used in patients with significant differences in respiratory mechanics between the 2 lungs owing to asymmetric or unilateral lung diseases. We report the case of a 66-year-old patient treated with ILV for a primary graft dysfunction occurred early after single lung transplantation. On intensive care unit admission, the patient was ventilated with pressure-controlled mechanical ventilation. Despite efforts to optimize ventilation and medical therapy, his clinical condition progressively worsened, manifesting hypoxemia, hypercapnia, and radiologic evidence of hyperinflation of the native lung, collapse of the graft, and mediastinal shift. The ventilation was therefore switched to ILV. A constant improvement in clinical conditions, arterial blood gas parameters, and radiologic findings was then obtained. The patients was weaned from mechanical ventilation and finally successfully extubated.  相似文献   
49.

Background

The extubation phase is an extremely critical moment in patients who have undergone orthotopic liver transplantation, who do not always have the advantage of long-lasting positive-pressure ventilation and positive expiratory end pressure; these factors can lead to splanchnic venous congestion, and this is why a rapid extubation can represent a great benefit for the graft.

Methods

The aim of this study was to compare the adaptive support ventilation (ASV) mode with the standard mode of weaning in our intensive care unit, synchronized intermittent mandatory ventilation with pressure support (P-SIMV), in patients who received orthotopic liver transplantation. ASV is a positive-pressure mode, in which pressure level and respiratory rate are automatically adjusted according to measured lung dynamics at each breath. Eligible patients were assigned to either ASV or P-SIMV group. The weaning protocol was based on the individual respiratory activity and structured in 4 different phases.

Results

The average length of intubation was significantly shorter in the ASV group than in the P-SIMV group (90 ± 13 vs 153 ± 22 minutes, P = .05). The total modifications to the ventilator settings were significantly larger in the P-SIMV group (1.5 ± 1 vs 6 ± 2; P = .003).

Conclusions

Our results suggest that although both procedures are safe and easy to apply, ASV is superior in terms of weaning times, and it simplifies respiratory management. The better patient-machine interaction in ASV has been highlighted by other authors for different clusters of patients.  相似文献   
50.
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