Effect of dialysis flux and membrane material on dyslipidaemia and inflammation in haemodialysis patients.

BACKGROUND: Dyslipidaemia, inflammation and oxidative stress are prominent risk factors that potentially cause vascular disease in haemodialysis patients. Dialysis modalities affect uraemic dyslipidaemia, possibly by modifying oxidative stress, but the effects of dialyser flux and membrane material on atherogenic remnant particles and oxidized low-density lipoproteins (LDL) are unknown. METHODS: We performed a randomized crossover study in 36 patients on haemodialysis to analyse the effect of dialyser flux and membrane material on plasma lipids, apolipoproteins and markers of inflammation and oxidative stress. Stable patients on low-flux dialysis with polysulphone for >/=6 weeks were assigned to high-flux polysulphone or high-flux modified cellulose with similar dialyser surface area and permeability characteristics and crossed over twice every 6 weeks. RESULTS: Thirty patients completed the study per protocol. Treatments with high-flux polysulphone and modified cellulose lowered serum triglyceride (by 20% and 10%, respectively; P<0.05) and remnant-like particle cholesterol by 32% (P<0.001) and 11% (NS) after the first 6 weeks of treatment. Oxidized LDL decreased significantly with high-flux polysulphone, but not with modified cellulose. Apolipoproteins CII and CIII were reduced, whereas the ratio CII/CIII was increased (all P<0.05). Acute-phase proteins and LDL and high-density lipoprotein cholesterol remained unaffected. CONCLUSIONS: This randomized crossover study demonstrates a potent effect of high-flux haemodialysis on uraemic dyslipidaemia. Polysulphone membrane material showed superiority on oxidatively modified LDL, an indicator of oxidative stress in haemodialysis patients.     

Hematopoietic reconstitution after bone marrow transplantation: Assessment with MR imaging and H-1 localized spectroscopy

Magnetic resonance (MR) studies were performed in 14 patients as early as possible (21–110 days) after bone marrow transplantation (BMT). MR characteristics of lumbar vertebral bone marrow were studied with T1-weighted spin-echo imaging, water- and fatselective imaging with a frequency-selective excitation technique, and point-resolved spatially localized proton spectroscopy. Signals from water and fat protons and their T1 and T2 values were analyzed. Water proton signal intensity correlated well with cellularity within bone marrow, as determined with parallel iliac crest biopsies. The fraction of signal from water in red bone marrow of patients with allogeneic transplants from siblings (four cases) was significantly higher than in four patients with autologous transplants. The latter showed very low cellularity in the period of about 4 weeks after BMT because of the cytotoxic pretreatment of the bone marrow. The MR results in six patients with allogeneic transplants from unrelated donors ranged widely, depending on the complications after BMT. Analysis of data obtained with the different techniques showed that water- and fat-selective MR imaging and spectroscopic methods are useful for noninvasive monitoring of hematopoietic reconstitution after BMT.     

Transpulmonary chemoembolization (TPCE) as a treatment for unresectable lung metastases

To evaluate tumor response after treating unresectable lung metastases with transpulmonary chemoembolization (TPCE) in palliative intention. From 2001 to 2005, 52 patients (mean: 59.8 years; 32 males/20 females) suffering from 106 unresectable lung metastases (mean:6 metastases/patient; range,1–21) were treated with 2–10 TPCE-sessions (mean: 3.3 sessions/patient). Metastases originated from primaries, including colorectal carcinoma (n = 20), breast cancer (n = 6), renal cellular carcinoma (n = 5), thyroid cancer (n = 4), cholangiocellular carcinoma (n = 2), leiomyosarcoma (n = 2), and others (n = 13). Tumor-feeding pulmonary arteries were selectively probed after puncturing the femoral vein, and administering 10 ml lipiodol, mitomycin C, and microspheres (Spherex) each via balloon catheter over pulmonary approach. During therapy, follow-up was accomplished at 4-week intervals using unenhanced and contrast-enhanced CT. After sequential therapy, follow-up was performed every 3 months for a period of 6 months up to 2.25 years. All patients tolerated the treatments well without major side effects or complications. In 24% (n = 13) moderate to high lipiodol uptake was found, while 75% (n = 39) of the tumors showed a low uptake. According to the RECIST criteria, “partial response” was achieved in 16 cases, “stable disease” in 11 cases, and “progressive disease” in 25 cases [mean survival: 17 months/median: 21.1 months (Kaplan-Meyer)]. According to these findings, TPCE is a well-tolerated procedure for palliative treatment of unresectable lung metastases.     

Comparison of 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine-enhanced MRI in 471 patients with known or suspected renal lesions: results of a multicenter, single-blind, interindividual, randomized clinical phase III trial

The purpose of this phase III clinical trial was to compare two different extracellular contrast agents, 1.0 M gadobutrol and 0.5 M gadopentate dimeglumine, for magnetic resonance imaging (MRI) in patients with known or suspected focal renal lesions. Using a multicenter, single-blind, interindividual, randomized study design, both contrast agents were compared in a total of 471 patients regarding their diagnostic accuracy, sensitivity, and specificity to correctly classify focal lesions of the kidney. To test for noninferiority the diagnostic accuracy rates for both contrast agents were compared with CT results based on a blinded reading. The average diagnostic accuracy across the three blinded readers (‘average reader’) was 83.7% for gadobutrol and 87.3% for gadopentate dimeglumine. The increase in accuracy from precontrast to combined precontrast and postcontrast MRI was 8.0% for gadobutrol and 6.9% for gadopentate dimeglumine. Sensitivity of the average reader was 85.2% for gadobutrol and 88.7% for gadopentate dimeglumine. Specificity of the average reader was 82.1% for gadobutrol and 86.1% for gadopentate dimeglumine. In conclusion, this study documents evidence for the noninferiority of a single i.v. bolus injection of 1.0 M gadobutrol compared with 0.5 M gadopentate dimeglumine in the diagnostic assessment of renal lesions with CE-MRI.

Subject‐specific modeling of muscle force and knee contact in total knee arthroplasty

Understanding the mechanical loading environment and resulting joint mechanics for activities of daily living in total knee arthroplasty is essential to continuous improvement in implant design. Although survivorship of these devices is good, a substantial number of patients report dissatisfaction with the outcome of their procedure. Knowledge of in vivo kinematics and joint loading will enable improvement in preclinical assessment and refinement of implant geometry. The purpose of this investigation was to describe the mechanics of total knee arthroplasty during a variety of activities of daily living (gait, walking down stairs, and chair rise/sit). Estimates of muscle forces, tibial contact load, location, and pressure distribution was performed through a combination of mobile fluoroscopy data collection, musculoskeletal modeling, and finite element simulation. For the activities evaluated, joint compressive load was greatest during walking down stairs; however, the highest contact pressure occurred during chair rise/sit. The joint contact moment in the frontal plane was mainly varus for gait and walking down stairs, while it was valgus during chair rise/sit. Excursion of the center of pressure on the tibial component was similar during each activity and between the medial and lateral sides. The main determinants of center of pressure location were internal–external rotation, joint load, and tibial insert conformity. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1576–1587, 2016.     

A comparative study of resource use and costs of renal, liver and heart transplantation

Organ transplantations are among the most expensive surgical treatments performed today, but estimates of the costs of organ transplantations vary widely between settings. The aim of this study is to estimate the costs of renal, liver and heart transplantation in a university hospital, adopting a similar costing methodology for all the three kinds of transplantation. Resource use data were collected from 803 patients transplanted between January 1995 and August 2001. Data about the time physicians and other hospital employees spent per transplantation were based on interviews. All costs from pretransplantation screening up to 3 years post-transplantation were taken into account and divided into costs of patient care and programme-related costs. Mean cost of renal transplantation varied from 70,723 Euros for cadaveric donor transplantations to 76,577 Euros for living donor transplantations. Mean costs of liver transplantation were 141,510 Euros and the mean costs of heart transplantation were 17, 828 Euros. Direct costs of patient care contributed to 79%, 87% and 92% of the costs of renal, liver and heart transplantation respectively. Inpatient hospital days were the largest contributor to the costs of patient care. The mean number of inpatient hospital days from pretransplantation screening to 3 years post-transplantation varied from 46 days for renal transplantation from a living donor to 58 days for renal transplantation from cadaveric donors, 83 days for heart transplantation and 108 days for liver transplantation. In conclusion, costs of liver and heart transplantation were approximately 2.0 and 2.5 times higher than the cost of renal transplantation. Length of inpatient hospital stay for transplantation did not change substantially over time between 1995 and 2001.     

Prophylaxis of thromboembolic complications after the Fontan operation (total cavopulmonary anastomosis)

OBJECTIVES: Thrombotic events have been reported as a major cause of morbidity after the Fontan procedure. There is no consensus concerning the postoperative mode and duration of anticoagulation prophylaxis. In a retrospective study, we evaluated the results of a prophylactic regimen on the basis of the surgical technique, potentially predisposing risk factors, and specific sequelae. METHODS: We evaluated 142 surviving patients after total cavopulmonary anastomosis (mean follow-up was 91.1 +/- 43.9 months). Prophylactic antithrombotic treatment was initiated in 86 patients with partial prosthetic venous pathway with acetylsalicylic acid; 45 patients with complete autologous tissue venous pathway or partial prosthetic venous pathway received no anticoagulation, and 11 patients received warfarin sodium (Coumadin). During long-term follow-up, 22 patients (12 after acetylsalicylic acid medication) crossed over to warfarin. RESULTS: Thrombotic events occurred in 10 patients (7%), with systemic venous thrombus formation in 8 (5.6%), stroke in 2 (1.4%), and a peak incidence during the first postoperative year. Eight of 10 patients were receiving heparin therapy mainly for prolonged postoperative immobilization. During follow-up, none of the 74 patients receiving acetylsalicylic acid and 1 of 40 patients without medication presented with thrombus formation. Under warfarin medication, 1 of 28 patients had an asymptomatic thrombus. Expected freedom from a thromboembolic event was 92% at 5 years and 79% at 10 years. There was no association with coagulation factor abnormalities. Protein-losing enteropathy was present in 4 of 10 patients. CONCLUSION: A prophylactic anticoagulation strategy that considers the surgical technique and potential predisposing circumstances proved effective in the prevention of late thrombotic complications after total cavopulmonary anastomosis. There is no need for routine anticoagulation during long-term follow-up after Fontan-type surgery in pediatric patients.     

Head-to-head comparison of B-type natriuretic peptide (BNP) and NT-proBNP in daily clinical practice

B-type natriuretic peptide (BNP; Abbott Diagnostics) and N-terminal proBNP (NT-proBNP, Roche Diagnostics) were compared in consecutive samples of 458 patients (mean age 60 years+/-16 years; 159 female, 299 male) sent for NT-proBNP measurement to investigate influences on both markers. BNP and NT-proBNP showed a close correlation with each other (r=0.89, p<0.0001). Using age- and gender-adjusted upper reference values the inter-rater agreement of both parameters was satisfactory (83%, Cohen's kappa coefficient=0.7). The combination of normal BNP and elevated NT-proBNP was significantly more frequent than vice versa (61 vs. 16 patients), and a calculated glomerular filtration rate<60 ml/min/1.73 m(2) was found in 39% of these patients. Multiple linear regression analysis revealed a significant influence of a reduced ejection fraction (<50%), renal dysfunction (calculated glomerular filtration rate<60 ml/min/1.73 m(2)), anemia, hypertension, age, and gender on both BNP and NT-proBNP. In conclusion, despite a close correlation and a satisfactory agreement between both markers in classification, frequent discrepancies in individual patients demonstrate that both markers are clinically not completely equivalent.