Robert J. Heyka

Lipoprotein(a) is an independent risk factor for cardiovascular disease in hemodialysis patients.

BackgroundAlthough serum lipoprotein(a) [Lp(a)J is an independent risk factor for atherosclerosis in the general population and Lp(a) levels are increased in hemodialysis patients, an association of Lp(a) with the risk of clinical events attributed to atherosclerosis has not been established in the chronic hemodialysis patient population. We therefore determined the association between Lp(a) levels and the risk of clinical events of presumed atherosclerotic etiology in a prospective study of an outpatient hemodialysis population. Methods and ResultsLp(a) was measured by radioimmunoassay in a baseline cardiovascular disease risk assessment in a consecutive series of 129 hemodialysis patients. The relation between baseline Lp(a) and clinical events of presumed atherosclerotic etiology was determined during 48 months of follow-up. Hemodialysis patients had a median Lp(a) concentration that was approximately four times as high as the median Lp(a) concentration in normal controls and twice as high as the levels in controls with angiographic evidence of coronary artery disease [median Lp(a), 38.4 versus 16.9 mg/dl; p < 0.001]. Baseline Lp(a) levels were no different in participants with or with no history of a previous clinical event at the time of the baseline examination. However, baseline Lp(a) concentration (p < 0.001) and a history of atherosclerotic clinical events (p = 0.001) were associated with clinical events during the period of follow-up. In contrast, baseline serum total cholesterol, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol, age, gender, race, or duration of hemodialysis were unrelated to this risk in the prospective study. Stepwise multiple logistic regression analysis demonstrated that serum Lp(a) concentration (p = 0.001) and the presence of a previous clinical event (p = 0.004) were the only independent contributors to the risk of a clinical event during the period of follow-up. ConclusionsLp(a) is an independent risk factor for clinical events attributed to atherosclerotic cardiovascular disease in patients receiving chronic hemodialysis treatment of end-stage renal disease.

Risk Factors for Hypertension in Chronic Hemodialysis Patients: Baseline Data from the HEMO Study

A cross-sectional analysis was performed to determine risk factors associated with hypertension in 1,238 chronic hemodialysis patients upon enrollment into the HEMO Study. The mean pre- and post-dialysis systolic blood pressure were 152.4 ± 25.0 (mean ± SD) and 137.8 ± 24.6 mm Hg, respectively. The mean pre- and post-dialysis diastolic blood pressures were 82.1 ± 14.8 and 74.7 ± 13.8 mm Hg, respectively. Less than 30% of the study cohort had blood pressures that were normotensive by JNC VI guidelines. Risk factors associated with higher pre- and post-dialysis systolic blood pressures included the presence of diabetes mellitus, older age, increased number of prescribed antihypertensive medications, lower hematrocrit, and absence of arrhythmias. Variables associated with higher pre- and post-dialysis diastolic blood pressures included younger age, increased number of prescribed anti-hypertensive medications and absence of arrhythmias. There was also a nonlinear relationship between blood pressure and prescribed total ultrafiltration volume. A total ultrafiltration volume of >2.5 kg was associated with an elevation in pre-dialysis systolic and diastolic blood pressures. A total ultrafiltration volume of ≤2.5 kg was associated with an elevation in post-dialysis systolic and diastolic blood pressures. These data on ultrafiltration volume suggest that higher pre-dialysis blood pressures may be associated with excessive interdialytic weight gains due to patient noncompliance with fluid restriction and that higher post-dialysis blood pressures may be associated with a prescribed dry weight that is higher than the patient’s true dry weight. Better management of these parameters may improve the prevalence and severity of hypertension in this population.

Hypophosphatemia during continuous hemodialysis is associated with prolonged respiratory failure in patients with acute kidney injury

BACKGROUND Hypophosphatemia is common in critically ill patients and has been associated with generalized muscle weakness, ventilatory failure and myocardial dysfunction. Continuous renal replacement therapy causes phosphate depletion, particularly with prolonged and intensive therapy. In a prospective observational cohort of critically ill patients with acute kidney injury (AKI), we examined the incidence of hypophosphatemia during dialysis, associated risk factors and its relationship with prolonged respiratory failure and 28-day mortality. METHODS This is a single-center prospective observational study. Included in the study were 321 patients with AKI on continuous dialysis as initial treatment modality. RESULTS Four per cent of the patients had a phosphate level <2 mg/dL at initiation and 27% during dialysis. Low baseline phosphate was associated with older age, female gender, parenteral nutrition, vasopressor support, low calcium, and high urea, bilirubin and creatinine, whereas hypophosphatemia during dialysis correlated with the ischemic acute tubular necrosis etiology of renal failure, intensive dose and longer therapy. Serum phosphate decline during dialysis was associated with higher incidence of prolonged respiratory failure requiring tracheostomy [odds ratio (OR) = 1.81; 95% confidence interval (CI) = 1.07-3.08], but not 28-day mortality (OR = 1.16; 95% CI = 0.76-1.77) in multivariable analysis. CONCLUSIONS Hypophosphatemia occurs frequently during dialysis, particularly with long and intensive treatment. Decline in serum phosphate levels during dialysis is associated with higher incidence of prolonged respiratory failure requiring tracheostomy, but not 28-day mortality.

BLOOD PRESSURE CONTROL IN CHRONIC DIALYSIS PATIENTS

In patients undergoing dialysis, hypertension is a common problem that exerts a significant influence on morbidity and mortality. Close to 80% of patients entering a dialysis program have hypertension (1, 2) defined as systolic pressure greater than 150 mm Hg or diastolic pressure greater than 90mm Hg. In addition, once dialysis is begun, control of hypertension may be less than optimal. A recent study of cardiac risk factors in dialysis patients (3) found 65% of nondiabetic patients and 87% of diabetic patients on dialysis had inadequate control of blood pressure. The prevalance of hypertension in the dialysis population varies with different etiologies of renal failure. Patients with tubulointerstitial disease have the lowest incidence of hypertension. In contrast, those with glomerulonephritis, primary vascular disease (nephrosclerosis, systemic sclerosis, hemolytic uremic syndrome) or diabetic nephropathy have hypertension at rates approaching 90 to 100% (4). This latter population is also more likely to have resistant hypertension once on dialysis.

Continuous Renal Replacement Therapy: Cost Considerations and Reimbursement

Cost considerations with CRRT are important and vary substantially among centers. Major areas of concern are personnel, equipment, supplies, CRRT modality chosen and patients chosen. Costs are higher with CRRT than with either IHD or APD. These cost differences narrow as greater amounts of therapy are delivered. There are signif‐ icant areas for cost control in CRRT. Each center must evaluate its program to find the areas of cost control that are potentially available.

Patency and Complications of Translumbar Dialysis Catheters

Translumbar tunneled dialysis catheter (TLDC) is a temporary dialysis access for patients exhausted traditional access for dialysis. While few small studies reported successes with TLDC, additional studies are warranted to understand the short‐ and long‐term patency and safety of TLDC. We conducted a retrospective analysis of adult patients who received TLDC for hemodialysis access from June 2006 to June 2013. Patient demographics, comorbid conditions, dialysis details, catheter insertion procedures and associated complications, catheter patency, and patient survival data were collected. Catheter patency was studied using Kaplan–Meier curve; catheter functionality was assessed with catheter intervals and catheter‐related complications were used to estimate catheter safety. There were 84 TLDCs inserted in 28 patients with 28 primary insertions and 56 exchanges. All TLDC insertions were technically successful with good blood flow during dialysis (>300 ml/minute) and no immediate complications (major bleeding or clotting) were noted. The median number of days in place for initial catheter, secondary catheter, and total catheter were 65, 84, and 244 respectively. The catheter patency rate at 3, 6, and 12 months were 43%, 25%, and 7% respectively. The main complications were poor blood flow (40%) and catheter‐related infection (36%), which led to 30.8% and 35.9% catheter removal, respectively. After translumbar catheter, 42.8% of the patients were successfully converted to another vascular access or peritoneal dialysis. This study data suggest that TLDC might serve as a safe, alternate access for dialysis patients in short‐term who have exhausted conventional vascular access.

Spontaneous perinephric hematoma due to acquired factor X deficiency in AL amyloidosis

Spontaneous perinephric hematoma (SPH) is a rare entity whose diagnosis is challenging because of its varied clinical presentation and lack of any specific etiology. We report a 34-year-old African-American male who presented with left flank pain and was found to have a large left perinephric hematoma, in the setting of undiagnosed AL amylodosis. The case illustrates that while a SPH due to the vascular angiopathy of amyloid is rare, when amyloidosis is associated with abnormal coagulation studies or bleeding at multiple sites, it should be considered because of its protean systemic manifestations and potential response to chemotherapy.

What Are the Most Common Errors in the Management of Renal Osteodystrophy

level of renal function has been demonstrated to restore PTH and ionized calcium levels to normal and to elevate above normal the serum levels of 1,25(OH)zD3. Although a number of trials have claimed reasonable short-term control of phosphate levels with calcium carbonate in both predialysis and dialysis patients, increased calcification has been observed in the main arteries of some patients (6) in addition to the peripheral vessels. Until a satisfactory nonaluminum-containing phosphate binder becomes available it would seem more appropriate to treat early renal impairment with dietary restriction of phosphate intake along with a combination of lowdose aluminum hydroxide and calcium carbonate. Provided adequate control of phosphate can be achieved, a low dose of a hydroxylated derivative of vitamin Ds could then be added in at a later date. References