Function In Dialysis Patients Research Articles

The Effects of Carnitine Supplementation in Hemodialysis Patients

Objectives: Patients receiving hemodialysis have been shown to be carnitine deficient due to many causes. Tissues, especially the skeletal muscle and myocardium, require carnitine for the production of energy. This study was performed to find out the effects of L-carnitine supplementation on muscular symptoms and cardiac functions in dialysis patients. Methods: Among 72 hemodialysis patients, 40 patients who showed decreased free carnitine levels were selected to receive L-carnitine intravenously after each hemodialysis session for 6 months. Before and after supplementation, echocardiography, various neurologic examinations and questionnaires were obtained. Results: After carnitine treatment for 6 months (1∼1.5 g per every hemodialysis session), the blood level of carnitine was increased more than 10 times (19.04±7.12 μmol/L vs. 267.24±69.94 μmol/L, P＜0.001). The left ventricular ejection fraction was improved in the patients who have less than 60% of ejection fraction (56.45±2.53% vs. 60.44±6.29%, P=0.03) after carnitine treatment. The neurological symptom score and isometric muscle power (pinch power) were improved, but the total neuropathy score, activities of daily living scale and grip power were not changed after carnitine supplementation on dialysis patients. Conclusion: Regular L-carnitine supplementation on hemodialysis patients can improve their left ventricular ejection fraction and some parts of functionality. (Ewha Med J 2012;35(2):89-94)

Reliability of 51Cr-EDTA plasma and urinary clearance as a measure of residual renal function in dialysis patients

Purpose: In dialysis patients, longer survival is associated with a higher residual renal function. Randomized controlled trials are conducted to clarify how residual renal function can be preserved. However, existing methods for measuring residual renal function are uncertain and there is a need for establishing a standard for measurements of glomerular filtration rate (GFR) in dialysis patients. Methods: 51Cr-EDTA clearances in plasma, urine, and dialysate were evaluated in a sample of 12 hemodialysis and 12 peritoneal dialysis patients. The patients’ condition was generally stable, and all patients were investigated twice within 4–10 days. Results: Plasma clearances of 51Cr-EDTA for all patients ranged between 2.1 and 30.8 mL/min/1.73m2, whereas urinary 51Cr-EDTA clearances ranged from 0.7–20.0 mL/min/1.73m2. This difference was statistically significant (p < 0.001). Week-to-week reproducibility expressed as coefficients of variation were below or equal to 10% for plasma clearances and 13% for urinary clearances in hemodialysis patients and 14% in peritoneal dialysis patients. Conclusions: This study demonstrated a difference between 51Cr-EDTA plasma and urinary clearances in dialysis patients. Plasma clearance of 51Cr-EDTA had the best reproducibility. For repeated measurements as in clinical prospective trials, we recommend 51Cr-EDTA plasma clearance based on blood sampling at 5 + 24 hours with subtraction of 51Cr-EDTA dialysate clearance in peritoneal dialysis patients. Further studies are needed to corroborate our findings.

Olfactory function in dialysis patients: a potential key to understanding the uremic state

Impaired olfactory function is a marker of neurologic dysfunction in the uremic state. Retained uremic toxins not adequately cleared with dialysis may undermine the integrity of the olfactory epithelium and olfactory bulb and malign central olfactory processing. The evidence suggests that only renal transplantation, with its concomitant thorough reversal of uremia, truly restores olfactory function to normal in end-stage renal disease. Testing of olfactory function may emerge as an important marker for the extent and resolution of uremia.

Preserving residual renal function in dialysis patients: an update on evidence to assist clinical decision making.

It has been documented that preservation of residual renal function in dialysis patients improves quality of life as well as survival. Clinical trials on strategies to preserve residual renal function are clearly lacking. While waiting for more results from clinical trials, patients will benefit from clinicians being aware of available knowledge. The aim of this review was to offer an update on current evidence assisting doctors in clinical practice.

Right Ventricular Diastolic Function in Dialysis Patients Could Be Affected by Vascular Access

Tricuspid annular plane excursion (TAPSE) measurement in echocardiography is a measure of heart diastolic distensibility: a low TAPSE indicates reduced ventricular distensibility leading to diastolic dysfunction. It is a good prognostic index for cardiac mortality risk in congestive heart failure patients, adding significant prognostic information to the NYHA clinical classification. Our study was designed to evaluate the effect of a single hemodialysis (HD) session on diastolic function and TAPSE, focusing on the effects of vascular access typology. Twenty chronically uremic patients (age 51 ± 10 years, dialytic age 24 ± 8 months), without overt heart disease, underwent conventional two-dimensional and Doppler echocardiography immediately before starting and 15 min after ending a mid-week HD session. Ten patients had distal radiocephalic arterovenous fistula (AVF), and 10 had permanent central venous catheters (CVC). The amount of fluid removed by HD was 2,706 ± 1,047 g/session. HD led to a reduction in TAPSE, left ventricle end-diastole volume, left ventricle end-systole volume, right ventricle end-diastole diameter, peak early transmitral flow velocity, and the ratio of early to late Doppler velocities of diastolic mitral flow. AVF patients showed greater right ventricle diameters versus CVC patients, while TAPSE appeared higher in the latter. Only the AVF patient group showed TAPSE values <15 mm. Our data confirm the effects of terminal uremia on right ventricle function (chamber dilation, impaired diastolic function), showing that these abnormalities are more frequent in AVF patients as opposed to CVC patients. It is reasonable to explain these clinical features as the effect of preload increase operated by AVF.

Hepatocellular transport and gastrointestinal absorption of lanthanum in chronic renal failure

Lanthanum carbonate is a new phosphate binder that is poorly absorbed from the gastrointestinal tract and eliminated largely by the liver. After oral treatment, we and others had noticed 2-3 fold higher lanthanum levels in the livers of rats with chronic renal failure compared to rats with normal renal function. Here we studied the kinetics and tissue distribution, absorption, and subcellular localization of lanthanum in the liver using transmission electron microscopy, electron energy loss spectrometry, and X-ray fluorescence. We found that in the liver lanthanum was located in lysosomes and in the biliary canal but not in any other cellular organelles. This suggests that lanthanum is transported and eliminated by the liver via a transcellular, endosomal-lysosomal-biliary canicular transport route. Feeding rats with chronic renal failure orally with lanthanum resulted in a doubling of the liver levels compared to rats with normal renal function, but the serum levels were similar in both animal groups. These levels plateaued after 6 weeks at a concentration below 3 microg/g in both groups. When lanthanum was administered intravenously, thereby bypassing the gastrointestinal tract-portal vein pathway, no difference in liver levels was found between rats with and without renal failure. This suggests that there is an increased gastrointestinal permeability or absorption of oral lanthanum in uremia. Lanthanum levels in the brain and heart fluctuated near its detection limit with long-term treatment (20 weeks) having no effect on organ weight, liver enzyme activities, or liver histology. We suggest that the kinetics of lanthanum in the liver are consistent with a transcellular transport pathway, with higher levels in the liver of uremic rats due to higher intestinal absorption.

Disordered mineral metabolism is not a risk factor for loss of residual renal function in dialysis patients

Recent studies showed that mineral metabolism disorders are associated with renal function loss in pre-dialysis patients, but their effects in dialysis patients are less well established. We examined associations between parameters of mineral metabolism and loss of residual renal function (RRF) in dialysis patients. We included 1468 incident haemodialysis (HD) and peritoneal dialysis (PD) patients who were not anuric at dialysis initiation from NECOSAD, a prospective multicentre cohort study. We studied the effects of plasma calcium, phosphorus, calcium-phosphorus product and intact PTH concentrations on loss of RRF. Cox regression models were applied to calculate relative risks of total loss of RRF, defined as anuria during the first 3 years of dialysis. The rate of decline of RRF over time was calculated using general linear mixed models. The mean (SD) age was 59 (15), 62% were men and 59% were treated with HD. We found that both HD and PD patients with the highest phosphorus (P < 0.0001) and calcium-phosphorus product (P < 0.0001) levels had the lowest baseline residual glomerular filtration rate (rGFR) values. During follow-up, 136 HD (15%) and 67 PD patients (12%) became anuric. After adjustment for baseline rGFR, there were no significant associations between parameters of mineral metabolism and the risk of becoming anuric. There were also no differences in the rate of decline in RRF between categories of plasma concentrations. Disordered mineral metabolism was neither associated with the risk of becoming anuric, nor with the rate of decline in RRF in dialysis patients. Differences in decline were mainly attributable to the baseline rGFR value.

Can FT3 levels facilitate the detection of inflammation or catabolism and malnutrition in dialysis patients?

Low serum free triiodothyronine (FT3) levels have been reported in a high percentage of chronic renal failure (CRF) patients and have been considered as independent predictors of mortality in both hemodialysis (HD) and peritoneal dialysis (PD). A reduction in thyroid function in dialysis patients could be a marker of malnutrition and/or inflammation. Our aim has been to evaluate the incidence of low T3 syndrome in a group of dialysis patients and analyze its relationship with different parameters of malnutrition and inflammation. PATIENTS AND METHODS We included 32 stable dialysis patients (24 HD and 8 DP); mean age +/- SD 71.2 +/- 11.7 years; 46.9% males; 15.6% diabetics; mean time on dialysis 47 +/- 43 months. The following parameters were measured in every patient: thyrothropin (TSH), Free T4 (FT4) and Free T3 (FT3); biochemical data related to nutritional status; anthropometric measurements, bioelectrical impedance vector analysis (BIVA), and dietary survey of three consecutive days. Statistical analysis was performed by using SPSS 11.0. Mean hormonal values of thyroid function were: TSH 2,2 +/- 1.5 U/ml (range: 0,4-5.0); FT4 14.7 +/- 2.3 pmol/l (range: 11.0-23.0) and FT3 4,0 +/- 0.71 pmol/l (range: 3.95-6.80). Only 2 patients (6.3%) showed low FT4 levels and another 2 patients increased TSH levels, whereas 17 patients (53.1%) presented with low FT3 levels. We did not found any correlation between serum FT3, FT4 and TSH levels. We found a correlation between FT3 and inflammation/nutritional parameters: prealbumin (r = 0,36; p = 0,04); transferrin (r = 0,40; p = 0,025); PCR (r = -0.38; p = 0,039); and IGF-I (r = 0,38; p = 0,03); body mass index (BMI) (r = 0,51; p = 0,002); arm circumference (AC) (r = 0,65; p = 0,000), and arm muscle circumference (AMC) (r = 0,72; p = 0,000). FT3 levels were also correlated with BIVA parameters: phase angle (r = 0,54; p = 0,002); muscle mass percentage (r = 0,49; p = 0,005); and cell mass percentage (r = 0,53; p = 0,02), but not with any data of fat mass. AMC was the only variable that independently correlated with FT3 levels in the multivariate regression analysis (r = 0,69; r2: 0,48; p = 0,000) Half of our dialysis patients have decreased levels of serum FT3 without alteration on FT4 or TSH. Low FT3 levels are correlated bioquimical and anthropometric parameters indicators of malnutrition and inflammation. Periodical measurement of FT3 levels could be used by clinicians as an accesible and reproducible method to detect such states.

Skin-autofluorescence a measure of tissue advanced glycation end-products (AGEs) is related to Diastolic Function in Dialysis Patients

Skin-autofluorescence a measure of tissue advanced glycation end-products (AGEs) is related to Diastolic Function in Dialysis Patients

Skin-Autofluorescence, a Measure of Tissue Advanced Glycation End-Products (AGEs), is Related to Diastolic Function in Dialysis Patients

Background Diastolic dysfunction is a frequent cause of heart failure, particularly in dialysis patients. Advanced glycation endproducts (AGEs) are increased in dialysis patients and are suggested to play a role in the development of diastolic dysfunction. The aim of our study was to assess whether AGE accumulation in dialysis patients is related to the presence of diastolic dysfunction. Methods and Results Data were analyzed from 43 dialysis patients, age 58 ± 15 years, of whom 65% were male. Diastolic function was assessed using tissue velocity imaging (TVI) on echocardiography. Tissue AGE accumulation was measured using a validated skin-autofluorescence (skin-AF) reader. Plasma N ε-(carboxymethyl)lysine (CML) and N ε-(carboxyethyl)lysine (CEL) were measured by stable-isotope-dilution tandem mass spectrometry. Plasma pentosidine was measured by high-performance liquid chromatography. Skin-AF correlated with mean E′ ( r = −0.51, P < .001), E/A ratio ( r = −0.39, P = .014), and E/E′ ( r = 0.38, P = .019). Plasma AGEs were not significantly associated with diastolic function. Multivariable linear regression analysis revealed that 54% of the variance of average E′ was explained by age ( P = .007), dialysis type ( P = 0.016), and skin-AF ( P = .013). Conclusions Tissue AGEs measured as skin-AF, but not plasma AGE levels, were related to diastolic function in dialysis patients. Although this may support the concept that tissue AGEs explain part of the increased prevalence of diastolic dysfunction in these patients, the ambiguous relation between plasma and tissue AGEs needs further exploring.

Residual Renal Function in Dialysis Patients: A Review of the Literature

Residual Renal Function in Dialysis Patients: A Review of the Literature

Cardiac disease in dialysis patients in a Jamaican Hospital: echocardiographic findings that predict mortality

The aim of the study was to assess, by echocardiography, the cardiac abnormalities in a group of patients with chronic renal failure and to determine the cardiovascular predictors of mortality. The study comprised forty-five patients from the Renal Unit, University Hospital of the West Indies, Kingston, Jamaica, and was undertaken between October 1, 1998 and July 31, 2000. All echocardiography was done by a single operator. The parameters assessed were systolic dysfunction, diastolic dysfunction, ejection fraction, regional wall motion abnormalities and valvular disease. Left ventricular cavity size, septal and posterior wall thickness were measured and left ventricular mass calculated. Demographic data were obtained directly from each patient by interview. The patients were mainly of African/mixed-African origin. Their mean age was 43.2 +/- 16.0 years. The average body mass index was 23.7 +/- 6.9. Twenty-eight (60.9%) patients were male and seventeen (39.1%) female. Hypertension, chronic glomerulonephritis and diabetes mellitus were the leading causes of chronic renal failure. Blood pressure was controlled at a mean value of 145/90 mm Hg pre-dialysis and 140/90 mm Hg postdialysis. The mean duration of renal failure was 2.8 years. Echocardiographic M-mode and two dimensional apical, four chamber view measurements indicated that mean left ventricular internal diameter (LVID) diastole was 55.7 +/- 7.9 mm (normal 38-56 mm) and LVID systole was 38.9 +/- 9.8 mm (normal 24-45 mm); the mean thickness of the chamber walls was 10.3 +/- 2.8 mm and 10.6 +/- 2.4 mm for the interventricular septum (normal 6-11 mm) and left ventricular posterior wall (normal 6-11 mm) respectively. Diastolic dysfunction was seen in 15 (34%) patients and systolic dysfunction in 12 (23%) patients who had ejection fractions less than 50%. The mean left ventricular ejection fraction was 56.3% +/- 16% (normal 65-85%), mean stroke volume was 82.9 +/- 27.2 mls (normal 51-96 ml). After 21 months enrolment in the study, Kaplan Meier analysis revealed a two-year mortality of 28.3%. Cox regression analysis indicated that a history of smoking current or past, low haemoglobin level, high aorta flow velocities, severity of mitral regurgitation and a negative association with serum creatinine were independent predictors of mortality. The correction of anaemia and control of other factors that impact negatively on cardiac function in dialysis patients is vital to enhance survival.

Residual renal function and dialysis modality: Is it really beneficial to preserve residual renal function in dialysis patients? (Review Article)

Residual renal function (RRF) contributes to the achievement of treatment adequacy in stage 5 chronic kidney disease (CKD-5) patients. It may facilitate patients' acceptance of renal replacement therapy (RRT) in allowing reduction of treatment time duration and minimising dietary and fluid restriction. It has been confirmed to improve dialysis patient outcomes. Attempts to preserve RRF in incident Stage 5 chronic kidney disease patients are still subject to intense controversies in the nephrology community. The aim of this review is to analyse the role of renal replacement modalities in the maintenance of RRF in dialysis patients. Under the scope of this manuscript, four questions are explored: Is the preservation of residual renal function an objective for dialysis adequacy? Does dialysis modality affect the decline of RRF? What are the factors implicated by this loss of RRF? At what expense can the maintenance of RRF be achieved in dialysis patients? Preservation of RRF is undoubtedly an interesting means to enhance the efficacy of renal replacement therapy and reduce dietary fluid restriction but it should not be considered as a goal of dialysis adequacy in dialysis patients. Further, preservation of RRF must be considered as a permanent trade-off between patient comfort and chronic fluid volume overload.

Effects of vitamin D on the cardiovascular system

Active vitamin D plays important roles not only in bone and mineral metabolism but also in the cardiovascular system. Cohort studies in hemodialysis patients demonstrated that use of active vitamin D analogs was associated with reduced risk of death, particularly death from cardiovascular disease. Treatment with vitamin D had beneficial effects on cardiac and immune functions in dialysis patients, and inflammatory markers in non-renal subjects. Also, anti-proteinuric effect was recently shown in chronic kidney disease. Experimentally, active vitamin D inhibits atherogenic cellular behaviors and activation of the renin-angiotensin system. Thus, active vitamin D is a regulator of cardiovascular and kidney functions.

The effect of uremia on platelet contractile force, clot elastic modulus and bleeding time in hemodialysis patients

Introduction Uremic bleeding frequently occurs in dialysis patients. Although its mechanism is not well characterized, acquired platelet dysfunction has been implicated in its pathogenesis. Skin bleeding time has been used to characterize platelet dysfunction in this population. However, the bleeding time is prone to error. The goal of this study was to compare the bleeding time to the novel platelet function parameters platelet contractile force and clot elastic modulus as well as platelet aggregation studies in controls and patients receiving maintenance hemodialysis. Materials and methods Forty-five subjects completed this study (25 controls, 20 dialysis). All subjects had the Ivy skin bleeding time procedure performed, as well as the collection of whole blood samples for the determination of platelet contractile force, clot elastic modulus, % von Willebrand Factor antigen, and platelet aggregation studies. Pearson's correlation determined the relationships between skin bleeding time and platelet function and clot structure parameters and markers of renal dysfunction. Results Bleeding time was significantly prolonged in the dialysis group relative to controls. The platelet function parameters were not significantly different between groups. There was a significant relationship between bleeding time and creatinine concentration, however, no relationship existed between bleeding time and platelet function parameters. Conclusions Skin bleeding time poorly correlates with measurements of platelet function. There were no significant differences noted in platelet function between the groups despite the prolongations in bleeding time in the dialysis group. These data may suggest that the bleeding time reflects perturbations in platelet adhesion or secretion, and not aggregation. Further study is needed to characterize platelet function in dialysis patients.

The effects of exercise training on cardiac function in dialysis patients

The effects of exercise training on cardiac function in dialysis patients

The importance of residual renal function for patients on dialysis

It is the goal of every practitioner involved in the care of dialysis patients to maximize survival and quality of life. The last two decades have seen a plethora of investigations that have sought to determine how this goal can be achieved. The bulk of the studies have, unfortunately, concentrated on small solute clearance and outcome (measured principally as mortality). The HEMO [1] and ADEMEX [2] studies suggested that this is not a fruitful avenue of investigation. However, the residual kidney function in patients on dialysis, particularly in those on peritoneal dialysis (PD), has proven to be a consistent and powerful predictor of mortality. We will review the evidence supporting the importance of residual renal function (RRF) on outcome, propose some explanations as to why this relationship exists, and suggest ways to prolong the renal function in dialysis patients.

Vitamin D and survival of hemodialysis patients

Vitamin D receptors are expressed not only in the classical target organs (bone, parathyroid glands, kidneys and intestine) but also in other non-classical targets including arteries, heart, immune system, endocrine organs, and nervous system. Therefore, the deficiency of active forms of vitamin D in uremia may explain various abnormalities in biological functions and survival disadvantage in this disease condition. Previous studies reported that treatment with vitamin D had beneficial effects on cardiac and immune functions in dialysis patients. A recent observational cohort study indicated that the mortality risk was different between the groups taking different types of vitamin D analogues. We found that patients on a low-dose oral alfacalcidol showed a significantly lower risk for cardiovascular death than those without vitamin D supplementation. Although these observations need further confirmation by randomized controlled studies, appropriate use of active forms of vitamin D may improve the outcomes of patients with chronic kidney disease.

Impaired left ventricular diastolic function in children with chronic renal failure

Diastolic dysfunction is frequent in adults with renal failure. However, in children with mild-to-moderate chronic renal insufficiency (CRI), it has not been evaluated. We compared diastolic function and assessed risk factors associated with diastolic dysfunction in children with CRI with those on dialysis. Thirty-three children with CRI, 17 on chronic dialysis, and 33 control patients, had echocardiography performed. Early diastole was assessed using indices of left ventricular (LV) relaxation derived from transmitral and tissue Doppler, and reported as the peak E/A wave ratio, and septal mitral annular velocities (Em). Late diastole was determined using an index of LV compliance (E/Em ratio). Left atrial (LA) dimension was also determined. Children with CRI had worse diastolic function (lower Em, and higher E/Em ratio than control patients, P < 0.001). Dialysis patients had worse diastolic function (lower E/A ratio and Em, and higher E/Em ratio, P < 0.001) than CRI children. LA dimension was higher in renal patients when compared with control patients (P < 0.001). In children on dialysis, LV relaxation (Em) was significantly related to left ventricular mass (LVM) index (r=-0.58, P= 0.04), and LV compliance (E/Em) was significantly associated with LA index (r= 0.67, P= 0.01), LVM index (r= 0.75, P < 0.01), hemoglobin level (r=-0.65, P= 0.02), serum phosphorus (r= 0.56, P= 0.05), and calcium-phosphorus ion product (r= 0.59, P= 0.04). Our results indicate that diastolic dysfunction is already present in children with mild-to-moderate CRI. Worse diastolic function in dialysis patients might be related to LV hypertrophy. The results suggest that children with advanced renal failure and diastolic dysfunction may be at risk for ultimate worsening of cardiac function over time.

Recovery of renal function in dialysis patients.

BackgroundAlthough recovery of renal functions in dialysis dependent patients is estimated to be greater than 1%, there are no indicators that actually suggest such revival of renal function. Residual renal function in dialysis patients is unreliable and seldom followed. Therefore renal recovery (RR) in dialysis dependent patients may remain unnoticed. We present a group of dialysis dependent patients who regained their renal functions. The aim of this project is to determine any indicators that may identify the recovery of renal functions in dialysis dependent patients.MethodsAll the discharges from the chronic dialysis facilities were identified. Among these discharges deaths, transplants, voluntary withdrawals and transfers either to another modality or another dialysis facility were excluded in order to isolate the patients with RR. The dialysis flow sheets and medical records of these patients were subsequently reviewed.ResultsEight patients with a mean age of 53.8 ± 6.7 years (± SEM) were found to have RR. Dialysis was initiated due to uremic symptoms in 6 patients and fluid overload in the remaining two. The patients remained dialysis dependent for 11.1 ± 4.2 months. All these patients had good urine output and 7 had symptoms related to dialysis. Their mean pre-initiation creatinine and BUN levels were 5.21 ± 0.6 mg/dl and 72.12 ± 11.12 mg/dl, respectively. Upon discontinuation, they remained dialysis free for 19.75 ± 5.97 months. The mean creatinine and BUN levels after cessation of dialysis were 2.85 ± 0.57 mg/dl and 29.62 ± 5.26 mg/dl, respectively, while the mean creatinine clearance calculated by 24-hour urine collection was 29.75 ± 4.78 ml/min. One patient died due to HIV complications. One patient resumed dialysis after nine months. Remaining continue to enjoy a dialysis free life.ConclusionRR must be considered in patients with good urine output and unresolved acute renal failure. Dialysis intolerance may be an indicator of RR among such patients.