Role of bicarbonate dialysis in prevention of serious arrhythmias in high‐risk cardiac patients undergoing regular hemodialysis

Background: Cardiac arrhythmias are considered as one of the most important causes of mortality in patients on hemodialysis. Arrhythmias frequently occur in patients with chronic renal failure on regular hemodialysis with reported incidences varying from 30–48% of patients. These abnormalities can span from supraventricular to severe ventricular arrhythmia. There is an increased frequency of occurrence and clustering of arrhythmias around the dialysis time. Aim of the study: To detect the difference between acetate and bicarbonate dialysis as regard to the type and frequency of arrhythmia in those patients. Study design: This study was done on 20 male patients age 51–73, all have history of heart disease. Patients were divided into 2 equal groups using acetate in group 1 and bicarbonate in group 2. All patients were on regular hemodialysis (4 hours, thrice weekly). Careful history and clinical examination were done. Pre‐dialysis investigations included serum creatinine, blood urea nitrogen, serum sodium, potassium, calcium and phosphorus, serum albumin, hemoglobin, and arterial blood gases. Post‐dialysis serum potassium and arterial blood gases were measured. ECG and forty‐eight hours ambulatory monitor (Holter monitor)(before, during, and after hemodialysis, till the end of the dialysis day and throughout the following day) were performed. Results: Group 1 showed significantly less post‐dialysis supraventricular arrhythmias than in dialysis day (210.9 ± 236 and 62.3 ± 14.4), respectively. Significantly less ventricular arrhythmias in post‐dialysis than in dialysis day (30.7 ± 50.4, and 106.2 ± 128.4), respectively. While in Group 2 there were insignificant differences regarding supraventricular arrhythmias (21.9 ± 28.9 and 16.6 ± 36.3) and ventricular arrhythmias (22.9 + 7.8 and 29.6 + 12.8) in dialysis day than in post‐dialysis day. There was significantly higher frequency of supraventricular and ventricular arrhythmias in the dialysis day in acetate hemodialysis in comparison to bicarbonate hemodialysis. Conclusion: Bicarbonate hemodialysis is less arrhythmogenic in comparison to acetate hemodialysis and has better effect on the blood pH and greater degree of base repletion. Continuous ambulatory ECG recording (Holter) is a useful tool in detecting arrhythmias in dialysis patients.     

Effects of end‐stage renal disease and dialysis modalities on blood ammonia level

Introduction: Uremia results in a characteristic breath odor (uremic fetor) which is largely due to its high ammonia content. Earlier studies have shown a strong correlation between breath ammonia and blood urea levels and a 10‐fold reduction in breath ammonia after hemodialysis in patients with chronic kidney disease. Potential sources of breath ammonia include: (i) local ammonia production from hydrolysis of urea in the oropharyngeal and respiratory tracts by bacterial flora, and (ii) release of circulating blood ammonia by the lungs. While the effects of uremia and hemodialysis on breath ammonia are well known their effects on blood ammonia are unknown and were explored here. Methods: Blood samples were obtained from 23 hemodialysis patients (immediately before and after dialysis), 14 peritoneal dialysis patients, and 10 healthy controls. Blood levels of ammonia, creatinine, urea, and electrolytes were measured. Findings: No significant difference was found in baseline blood ammonia between hemodialysis, peritoneal dialysis and control groups. Hemodialysis procedure led to a significant reduction in urea concentration (P < 0.001) which was paradoxically accompanied by a modest but significant (P < 0.05) rise in blood ammonia level in 10 of the 23 patients studied. Change in blood ammonia pre‐ and post‐hemodialysis correlated with change in serum bicarbonate levels (r = 0.61, P < 0.01). On subgroup analysis of patients who had a rise in blood ammonia levels after dialysis, there was a strong correlation with drop in mean arterial pressure (r = 0.88, P < 0.01). The nadir intradialytic systolic blood pressure trended lower in the hemodialysis patients who had a rise in blood ammonia compared to the patients who manifested a fall in blood ammonia (124 ± 8 vs. 136 ± 6 mmHg respectively, P = 0.27). Discussion: Fall in blood urea following hemodialysis in ESRD patients was paradoxically accompanied by a modest rise in blood ammonia levels in 43% of the patients studied, contrasting prior reported effects of hemodialysis on breath ammonia. In this subgroup of patients, changes in blood ammonia during hemodialysis correlated with rise in blood bicarbonate and fall in mean arterial blood pressure.     

The effects of hemodialysis treatment on the level of DNA strand breaks and oxidative DNA lesions measured by the comet assay

Hemodialysis patients have a higher risk for oxidative stress‐related complications, such as cardiovascular disease and cancer. The increased level of oxidative stress is due to several factors, e.g., the hemodialysis treatment itself and the uremic state. In the present study, the effects of dialysis treatment on the level of DNA breaks and oxidative DNA lesions in mononuclear cells were measured with the comet assay. Factors possibly affecting DNA damage (reported as % DNA in tail) such as the duration of dialysis, time since last dialysis session, years of dialysis treatment, nutritional status (measured as protein catabolic rate), age, and diabetes were also investigated. The levels of DNA breaks (13.6 ± 4.7 before dialysis) and oxidative DNA lesions (7.9 ± 4.8 before dialysis) were significantly higher in dialysis patients (n = 31) compared to the levels of DNA breaks (5.8 ± 1.1) and oxidative DNA lesions (3.4 ± 1.7) in 10 healthy controls (P < 0.001). A decrease of DNA breaks was observed after dialysis (P = 0.038), and the level of oxidative DNA lesions was higher when the time between two treatment sessions were 68 hours compared to 44 hours (P < 0.001). Older subjects had a higher level of DNA breaks (P = 0.003), a good nutritional status predicted a lower level of DNA breaks (P < 0.001), and the duration of the dialysis session was inversely correlated with oxidative DNA lesions (P = 0.014). Diabetes or years of dialysis treatment did not affect DNA damage. The observations in the present study suggest that accumulation of uremic toxins induce DNA damage. The hemodialysis treatment seems to change the DNA damage.     

Does the presence of an arteriovenous fistula alter changes in body water following hemodialysis as determined by multifrequency bioelectrical impedance assessment?

Multifrequency bioelectrical impedance assessments (MFBIAs) aid clinical assessment of hydration status for hemodialysis (HD) patients. Many MFBIA devices are restricted to whole body measurements and as many patients dialyze using arteriovenous fistulas (AVFs), we wished to determine whether AVFs affected body water measurements. We reviewed pre‐ and post‐HD segmental MFBIA measurements in 229 patients attending for midweek HD sessions. Up to 144 were dialyzed with a left arm AVF (L‐AVF), 42 with a right arm AVF (R‐AVF), and 43 by central venous access catheter (CVC). Water content and lean tissue were greater in the left compared to right arm in those patients with L‐AVFs both pre and post dialysis (pre 2.1 ± 0.7 vs. 2.0 ± 0.7 L, and post 1.9 ± 0.6 vs. 1.8 ± 0.6 L and pre 2.65 ± 0.9 vs. 2.56 ± 0.8 kg, and post 2.34 ± 0.8 vs. 2.48 ± 0.8 vs. 2.34 ± 0.8 kg, respectively) and were also greater in the right compared to left arm for those patients dialyzing with R‐AVFs (pre‐HD 1.92 ± 0.5 vs. 1.86 ± 0.6 L and post‐HD 1.79 ± 0.5 vs. 1.7 ± 0.5 L, and pre‐HD 2.47 ± 0.6 vs. 2.38 ± 0.7 kg and post‐HD 2.3 ± 0.74 vs. 1.28 ± 0.7 kg, respectively), all Ps < 0.05. There were no significant differences in arm volumes or composition pre or post dialysis in those dialyzing with CVCs. Segmental MFBIA detects differences in arm water and lean mass in patients with AVFs. The presence on an AVF increases the water content in the ipsilateral arm both pre and post HD. This increased water content of the fistula arm will not be detected by whole body bioimpedance devices.     

Acute complicating symptoms during hemodialysis sessions have well correlation with deranged blood pressure regulation

Objective: This observational study was undertaken to evaluate the frequency of acute complications occurring during dialysis sessions and their association with other clinical and biochemical parameters. Method: Forty‐six maintenance hemodialysis patients were selected and evaluated. Mean of the weekly evaluations of different parameters over a three‐month period is presented here. Result: Age of study subjects was 39 ± 13 years and body mass index (BMI) 21 ± 4 kg/m². Duration of hemodialysis was 41 ± 29 months. Most of the patients were hypertensive (98%), taking multiple anti‐hypertensive drugs. Mean of the blood pressures before and at the end of dialysis sessions over the three month period were: systolic blood pressure (SBP) 159 ± 18 vs. 163 ± 22 (p < 0.05) and diastolic blood pressure (DBP) 92 ± 13 vs. 87 ± 7 mmHg (p < 0.003). Frequency of acute complicating symptoms during dialysis sessions were: headache (75%), rise in blood pressure (73%), leg cramps (67%), vomiting (60%), palpitation (58%), sweating (52%), and hypotension (35%). Raised blood pressure showed a positive correlation with headache (r = 0.50, p < 0.01) and sweating (r = 0.53, p < 0.05). Vomiting and palpitation were more frequent at low post‐dialysis blood pressure (vomiting vs. post‐SBP‐r = ?0.41, p < 0.05 and palpitation vs. post‐DBP‐r = ?0.48, p < 0.05), and these patients were likely to get inadequate dialysis (hypotension vs. Kt/V‐r = ?0.63, p < 0.01). Pre and post dialysis weight variation was 53 ± 11 vs. 51 ± 11 kg (p < 0.001), average ultrafiltration during dialysis (UF)?2.39 (0.5–4) liter and single session Kt/V was 0.95 ± 0.38. The rising tendency of post‐dialysis blood pressure correlated positively with increasing UF (SBP vs. UF‐r = 0.36, p < 0.01 and DBP vs. UF‐r = 0.25, p < 0.05). Conclusion: From this study it may be concluded that acute complications during dialysis sessions have a significant correlation with deranged blood pressure regulation, and optimum control of blood pressure could provide better dialysis.     

Changes in biochemical,hemodynamic, and dialysis adherence parameters in hemodialysis patients during Ramadan

This paper aimed to study the effect of Ramadan fasting on biochemical and clinical parameters and compliance for dialysis. A prospective multicenter observational cross‐sectional study comparing fasting with a non‐fasting stable adult hemodialysis patients for demographic and biochemical parameters, compliance with dialysis, inter‐dialytic weight gain, pre‐ and post‐blood pressure, and frequency of intradialytic hypotensive episodes was carried out. Six hundred thirty‐five patients, of whom 64.1% fasted, were studied. The fasters were younger (53.3 ± 16.2 vs. 58.4 ± 16.1 years; P = 0.001) but had similar duration on dialysis (P = 0.35). More fasters worked (22.0% vs. 14.6%; P = 0.001) and missed dialysis sessions during Ramadan. No differences were noted between groups in sex, diabetic status, or dialysis shift or day. There were no differences in the pre‐ and post‐dialysis blood pressure; serum potassium, albumin or weight gain; diabetic status; sex; and dialysis shift time or days. However, serum phosphorous was significantly higher in the fasting group (2.78 ± 1.8 vs. 2.45 ± 1.6 mmol/L; P = 0.045). There were no intragroup differences in any of the parameters studied when comparing the findings during Ramadan with those in the month before Ramadan. Fasters were significantly younger and more likely to be working, to miss dialysis sessions, and to have higher serum phosphorous levels. No other differences were observed.     

Assessment of subjective and hemodynamic tolerance of different high‐ and low‐flux dialysis membranes in patients undergoing chronic intermittent hemodialysis: A randomized controlled trial

Clinical experience and experimental data suggest that intradialytic hemodynamic profiles could be influenced by the characteristics of the dialysis membranes. Even within the worldwide used polysulfone family, intolerance to specific membranes was occasionally evoked. The aim of this study was to compare hemodynamically some of the commonly used polysulfone dialyzers in Switzerland. We performed an open‐label, randomized, cross‐over trial, including 25 hemodialysis patients. Four polysulfone dialyzers, A (Revaclear high‐flux, Gambro, Stockholm, Sweden), B (Helixone high‐flux, Fresenius), C (Xevonta high‐flux, BBraun, Melsungen, Germany), and D (Helixone low‐flux, Fresenius, Bad Homburg vor der Höhe, Germany), were compared. The hemodynamic profile was assessed and patients were asked to provide tolerance feedback. The mean score (±SD) subjectively assigned to dialysis quality on a 1–10 scale was A 8.4 ± 1.3, B 8.6 ± 1.3, C 8.5 ± 1.6, D 8.5 ± 1.5. Kt/V was A 1.58 ± 0.30, B 1.67 ± 0.33, C 1.62 ± 0.32, D 1.45 ± 0.31. The low‐ compared with the high‐flux membranes, correlated to higher systolic (128.1 ± 13.1 vs. 125.6 ± 12.1 mmHg, P < 0.01) and diastolic (76.8 ± 8.7 vs. 75.3 ± 9.0 mmHg; P < 0.05) pressures, higher peripheral resistance (1.44 ± 0.19 vs. 1.40 ± 0.18 s × mmHg/mL; P < 0.05) and lower cardiac output (3.76 ± 0.62 vs. 3.82 ± 0.59 L/min; P < 0.05). Hypotension events (decrease in systolic blood pressure by >20 mmHg) were 70 with A, 87 with B, 73 with C, and 75 with D (P < 0.01 B vs. A, 0.05 B vs. C and 0.07 B vs. D). The low‐flux membrane correlated to higher blood pressure levels compared with the high‐flux ones. The Helixone high‐flux membrane ensured the best efficiency. Unfortunately, the very same dialyzer correlated to a higher incidence of hypotensive episodes.     

N‐acetylcysteine may improve residual renal function in hemodialysis patients: A pilot study

Clinical outcomes in chronic dialysis patients are highly dependent on preservation of residual renal function (RRF). N‐acetylcysteine (NAC) may have a positive effect on renal function in the setting of nephrotoxic contrast media administration. In our recent study, we showed that NAC may improve RRF in peritoneal dialysis patients. The aim of the present study was to investigate the effect of NAC on RRF in patients treated with chronic hemodialysis. Prevalent chronic hemodialysis patients with a residual urine output of at least 100 mL/24 hours were included. The patients were administered oral NAC 1200 mg twice daily for 2 weeks. Residual renal function was assessed at baseline and at the end of treatment using a midweek interdialytic urine collection for measurement of urine output and calculation of residual renal Kt/V and glomerular filtration rate (GFR). Residual GFR was measured as the mean of urea and creatinine residual renal clearance. Each patient served as his own control. Twenty patients were prospectively enrolled in the study. Administration of NAC 1200 mg twice daily for 2 weeks resulted in significant improvement in RRF: urine volume increased from 320 ± 199 to 430 ± 232 mL/24 hours (P < 0.01), residual renal Kt/V increased from 0.19 ± 0.12 to 0.29 ± 0.14 (P < 0.01), and residual GFR increased from 1.6 ± 1.6 to 2.4 ± 2.3 mL/minute/1.73 m² (P < 0.01). N‐acetylcysteine may improve RRF in patients treated with chronic hemodialysis.     

The relationship between symptoms and blood pressure during maintenance hemodialysis

Intradialytic hypotension (IDH) is a detrimental complication of maintenance hemodialysis, but how it is defined and reported varies widely in the literature. European Best Practice Guideline and Kidney Disease Outcomes Quality Initiative guidelines require symptoms and a mitigating intervention to fulfill the diagnosis, but morbidity and mortality outcomes are largely based on blood pressure alone. Furthermore, little is known about the incidence of asymptomatic hypotension, which may be an important cause of hypoperfusion injury and impaired outcome. Seventy‐seven patients were studied over 456 dialysis sessions. Blood pressure was measured at 15‐minute intervals throughout the session and compared with post‐dialysis symptom questionnaire results using mixed modeling to adjust for repeated measures in the same patient. The frequency of asymptomatic hypotension was estimated by logistic regression using a variety of commonly cited blood pressure metrics that describe IDH. In 113 sessions (25%) where symptoms were recorded on the questionnaire, these appear not to have been reported to dialysis staff. When symptoms were reported (293 sessions [64%]), an intervention invariably followed. Dizziness and cramp were strongly associated with changes in systolic blood pressure (SBP), but not diastolic blood pressure. Nausea occurred more frequently in younger patients but was not associated with falls in blood pressure. Thresholds that maximized the probability of an intervention rather than a session remaining asymptomatic were SBP <100 mmHg or a 20% reduction in SBP from baseline. The probability of SBP falling to <100 mmHg in an asymptomatic session was 0.23. Symptoms are frequently not reported by patients who are hypotensive during hemodialysis, which leads to an underestimation of IDH if symptom‐based definitions are used. A revised definition of IDH excluding patient‐reported symptoms would be in line with literature reporting morbidity and mortality outcomes and include sessions in which potentially detrimental asymptomatic hypotension occurs.     

Use of 3‐hour daily hemodialysis and paricalcitol in patients with severe secondary hyperparathyroidism: A case series

Patients with poor metabolic control receiving conventional hemodialysis are at risk for developing severe secondary hyperparathyroidism. We postulated that daily hemodialysis may be effective at controlling parathyroid hormone (PTH) in the setting of severe secondary hyperparathyroidism by improving the control of hyperphosphatemia and allowing increased use of vitamin D analogs. We present 5 patients with severe secondary hyperparathyroidism (median iPTH=1783 pg/mL) who were treated with 3‐hour daily hemodialysis (3 hours × 6 times a week). Daily hemodialysis, at 1 year, was associated with a 70.4% reduction in median PTH (1783 pg/mL [interquartile range: 1321–1983]–472 pg/mL [334, 704], P<0.001). Additionally, there was an increase in paricalcitol dose from 0 mcg/d to 10.8 (2.00, 11.7) mcg/d, a 39% reduction in calcium × phosphorus product (80.3 ± 26.8–48.9 ± 14.0, P<0.01), a 52% reduction in serum phosphorus (9.90 ± 2.34–4.75 ± 0.79 mg/dL, P<0.0001), and a 17.6% increase in serum calcium (8.18 ± 2.04–9.62 ± 0.93 mg/dL, P<0.01). Three‐hour daily hemodialysis with the use of high‐dose paricalcitol is associated with improved control of severe secondary hyperparathyroidism.     

Removal of vancomycin administered during dialysis by a high‐flux dialyzer

Introduction: Hemodialysis patients frequently receive vancomycin for treatment of gram‐positive bacterial infections. This drug is most conveniently administered in outpatient dialysis units during the hemodialysis treatment. However, there is a paucity of data on the removal of vancomycin by high‐flux polyamide dialyzers. Methods: This is a prospective crossover study in which seven uninfected chronic hemodialysis patients at three dialysis units received vancomycin 1 gram intravenously over one hour immediately after the dialysis treatment (Phase 1), and vancomycin 1.5 grams during the last hour of dialysis treatment using a polyarylethersulfone, polyvinylpyrrolidone, polyamide high‐flux (Polyflux 24R) dialyzer (Phase 2). There was a three‐week washout period between phases. Serial serum vancomycin concentrations were used to determine the removal of vancomycin when administered during dialysis. Findings: Dialysis removed 35 ± 15% (range 18‐56%) of the vancomycin dose when administered during the last hour of dialysis. The calculated area under the curve (AUC) of vancomycin levels for 0‐44.5 hours from the start of infusion were similar between the two phases (AUC_{Phase 1} 884 ± 124 mg‐hr/L, mean ± SD; AUC_{Phase 2} 856 ± 208 mg‐hr/L; P=0.72). Serum vancomycin concentrations immediately prior to the next dialysis treatment following vancomycin administration were also similar between the two phases (13.1 ± 2.7 mg/L in Phase 1 and 12.3 ± 3.3 mg/L in Phase 2; P=0.55). Discussion: When using a polyarylethersulfone, polyvinylpyrrolidone, and polyamide high‐flux HD membrane with a 24R Polyflux dialyzer, vancomycin can be administered during the last hour of dialysis if the dose that is prescribed for intra‐dialysis dosing is empirically increased to account for intra‐dialytic drug removal.     

Platelet activation and clotting cascade activation by dialyzers designed for high volume online hemodiafiltration

Introduction: Hemodialysis patients are pro‐thrombotic. Higher volume online postdilutional hemodiafiltration (OL‐HDF), with increasing hematocrit increases the risk of clotting in the extracorporeal circuit (ECC). We wished to determine whether OL‐HDF increased platelet activation and ECC clotting. Methods: Coagulation parameters, platelet, white cell, and endothelial activation markers were measured at the start and end of dialysis sessions in 10 patients and also pre‐ and post‐dialyzer after 15 minutes using two different dialyzers designed for high volume OL‐HDF; cellulose triacetate (TAGP) and polysulphone (PS), and polyvinylpyrrolidone (PVP). Patients were anticoagulated with a heparin bolus. Findings: At the start of OL‐HDF, D dimers, thrombin antithrombin complexes (TATs), and soluble adhesions molecules (sICAM‐1 and sVCAM‐1) were increased. Post‐treatment soluble P selectin (PS/PVP 26.7 ± 7.1 versus 36.6 ± 9.9; TAGP 28.7 ± 7.2 versus 43.5 ± 8.4 ng/ml, P < 0.001), and soluble CD40 ligand (PS/PVP 297 ± 228 versus 552 ± 272, TAGP 245 ± 187 versus 390 ± 205 ng/ml, P < 0.05) increased. Post‐dialyzer concentrations increased versus pre‐dialyzer for tissue factor (PS/PVP 117 ± 12 versus 136 ± 16, TAGP 100 ± 25 versus 128 ± 40 ng/ml, P < 0.05), factor VIIIc (PS/PVP 174 ± 54 versus 237 ± 83, TAGP 163 ± 60 versus 247 ± 102 IU/ml, P < 0.01), sVCAM‐1 (PS/PVP 782 ± 64 versus 918 ± 140, TAGP 722 ± 121 versus 889 ± 168 ng/ml, P < 0.01), and D‐dimers (PS/PVP 292 ± 132 versus 355 ± 167, TAGP 300 ± 129 versus 391 ± 171 ng/ml, P < 0.001). There was no macroscopic thrombus noted in the ECC, and no increase in microparticles, platelet factor‐4, or TATs. Discussion: Despite being pro‐thrombotic, with activation of platelets, and lymphocytes during passage through ECC, no macroscopic clotting, or increased TATs were noted during OL‐HDF, and no major differences between cellulosic and polysulphone dialyzers.     

The effect of hemodialysis session on postural strategies in older end‐stage renal disease patients

Patients suffering from end‐stage renal disease experience multiple disabilities, such as muscle wasting, weakness, higher postural sway, and fall rates compared with healthy population, which has a negative effect on physical functioning and autonomy. The vital treatment of hemodialysis is recognized to induce important post‐hemodialysis fatigue, hypotension, cramps, and headache due to the rapid fluid redistribution, among others. Nevertheless, even the well‐known negative effect of aforementioned consequences of hemodialysis treatment, its effect on physical function, especially postural balance, is unclear. Thus, this study hypothesized the adverse effect of hemodialysis treatment on postural sway in 12 end‐stage renal disease patients (mean age 63.3 ± 11 years) through the analysis of center‐of‐pressure (COP) trajectories recorded before and immediately after hemodialysis session. Evident postural alterations were observed at post‐hemodialysis balance assessment for COP position‐based (Fs < 7.7, P < 0.02) and COP velocity‐based variables (Fs > 2.33, P < 0.05), without changes in complexity of COP time series in anteroposterior and mediolateral directions. These results suggest that period after hemodialysis treatment is particularly unsafe, as evidenced by important disability in postural control, and highlight the importance of the medical support and falls‐related prevention strategies of these older frail patients after hemodialysis treatment.     

Heparin Use in Daily Hemodialysis

More frequent dialysis is thought to be associated with increased heparin requirements; however, limited data are available which compare heparin requirements of conventional to daily dialysis. Objectives: To determine differences in heparin dose during conventional thrice‐weekly dialysis (CHD) compared to daily hemodialysis (DHD). Methods: All patients within the daily home hemodialysis at the Northwest Kidney Centers were evaluated for heparin dose both pre‐ and post initiation of daily hemodialysis. Patients on DHD received an initial bolus of heparin, without a continuous heparin drip, and supplemental heparin midway through the dialysis run as needed to maintain adequate activated clotting times (ACTs). CHD patients received a heparin bolus, followed by initiation of heparin drip as needed to maintain adequate ACTs. Results: Of the 1117 patients who dialyze at the NKC, 55% were Caucasian, 21% African‐American, 20% Asian/Pacific Islander, and 35% were of other ethnicity. The majority of patients were greater than 60 years (56%), while 36% ranged from 40–60 years and 13% ranged from 20–40 years. Male patients constituted 54% of patients. Diabetes was the primary cause of renal disease (36%), followed by hypertension (21%) and glomerular disease (18%). Of those patients in the home hemodialysis program (n = 45), 10 patients started daily home hemodialysis using the Aksys daily home hemodialysis system. Of those, the majority was male (100%), Caucasian (78.8%) with an average age of 46.7 ± 18 years. Glomerulonephritis was the primary cause of end‐stage renal disease (40%), while the percentages of other diseases were similar [Alport's syndrome (20%), hypertension (20%) and diabetes (10%)]. Compared to initial DHD heparin requirements (10,111 ± 2219 units), CHD heparin dose requirements (6833 ± 2715 units) were significantly lower (p = 0.045); however, total heparin needs were similar between groups (10,166 ± 4380 units vs. 10,778 ± 2959 units) (p = 0.324). Conclusion: Although patients initiating DHD have greater initial heparin requirements than when on CHD, total heparin doses remain similar to those required on conventional thrice‐weekly hemodialysis. Greater initial heparin doses required during short daily dialysis appear safe compared to those of conventional dialysis.     

Heparin‐grafted dialysis membrane allows minimal systemic anticoagulation in regular hemodialysis patients: A prospective proof‐of‐concept study

This prospective, multicenter, proof‐of‐concept study aimed to evaluate the possibility to reduce the ordinary heparin dose and the systemic anti‐Xa activity during hemodialysis (HD) sessions using a new heparin‐grafted HD membrane. In 45 stable HD patients, the use of a heparin‐grafted membrane with the ordinary heparin dose was followed by a stepwise weekly reduction of dose. Reduction was stopped when early signs of clotting (venous pressure, quality of rinse‐back) occurred during two out of three weekly HD sessions. Heparin dose was decreased for 67% of patients resulting in the lowering of these patients' anti‐Xa activity by 50%. Dose reductions were achieved with both types of heparin (low‐molecular‐weight heparin: 64 ± 14 to 35 ± 12 IU/kg, P < 0.0001; unfractionated heparin: 82 ± 18 to 46 ± 13 IU/kg, P < 0.0001) resulting in a decrease of anti‐Xa activity at dialysis session end (low‐molecular‐weight heparin: 0.51 ± 0.25 to 0.25 ± 0.11 IU/mL, P < 0.0001; unfractionated heparin: 0.28 ± 0.23 to 0.13 ± 0.07 IU/mL, P < 0.0001). Failure to further decrease heparin dose was related to signs of clotting in blood lines (57% of sessions), in dialyzer (9%), or both (34%). Significant reduction of heparin dose and anti‐Xa activity at the end of HD sessions was possible in stable HD patients using heparin‐grafted membrane. HD patients who require low anti‐Xa activity at the end of HD sessions might benefit from a heparin‐grafted membrane to reduce bleeding risk and other heparin adverse events.     

Malnutrition‐inflammation‐coronary calcification in pediatric patients receiving chronic hemodialysis

Malnutrition, inflammation, and renal osteodystrophy parameters with resultant coronary calcification (CC) are associated with increased cardiovascular mortality in adults. Previous pediatric studies demonstrated CC in children but none assessed for an association between inflammation, malnutrition, renal osteodystrophy, and CC. To assess CC, ultrafast computerized tomogram was obtained for 16 pediatric patients (6 females; median age 17.2 years; range 9.1–21.2 years) receiving hemodialysis for ≥2 months. Inflammation was assessed by serum IL‐6, IL‐8, and C‐reactive protein levels on the day of the computerized tomogram scan; nutrition parameters included serum albumin, cholesterol, the body mass index standard deviation score, and normalized protein catabolic rate. Renal osteodystrophy parameters included time‐averaged serum calcium, phosphorus, total PTH, and calcitriol/calcium dose. Patients received hemodialysis thrice‐weekly; mean single pool Kt/V 1.48±0.13; and mean normalized protein catabolic rate 1.27±0.17 g/kg/day. Five of 16 patients had CC. Patients with CC were older (19.1±2.1 vs. 15.4±3.1 months; P=0.03), had longer dialysis vintage (49.4±15.3 vs. 17.2±10.5 months, P=0.0002), lower serum cholesterol (122±17.7 vs. 160.4±10.6 mg/dL, P=0.02), and higher phosphorus (9.05±1.2 vs. 6.1±0.96 mg/dL, P=0.0001). Mean serum albumin and normalized protein catabolic rate did not differ for patients with CC. All patients had elevated IL‐6 and IL‐8 levels compared with healthy norms; the mean IL‐6, IL‐8, and C‐reactive protein levels were not different in patients with CC. Coronary calcification was prevalent in older children receiving maintenance hemodialysis with a longer dialysis vintage. Worse renal osteodystrophy control and malnutrition (low cholesterol) may contribute to CC development.     

Effect of alternate night nocturnal home hemodialysis on anemia control in patients with end‐stage renal disease

Nocturnal home hemodialysis (NHHD) has shown promising results in various clinical parameters. Whether NHHD provide benefit in anemia management remains controversial. This study aims to investigate whether anemia and erythropoiesis‐stimulating agent (ESA) requirement are improved in patients receiving alternate night NHHD compared with conventional hemodialysis (CHD). In this retrospective controlled study, a clinical data of 23 patients receiving NHHD were compared with 25 in‐center CHD patients. Hemoglobin level, ESA requirement, iron profile, and dialysis adequacy indexes were compared between the two groups. Hemoglobin level increased from baseline of 9.37 ± 1.39 g/dL to 11.34 ± 2.41 g/dL at 24 months (P < 0.001) and ESA requirement decreased from 103.44 ± 53.55 U/kg/week to 47.33 ± 50.62 U/kg/week (P < 0.001) in NHHD patients. ESA requirement further reduced after the first year of NHHD (P = 0.037). Standard Kt/V increased from baseline of 2.02 ± 0.28 to 3.52 ± 0.30 at 24 months (P < 0.001). At 24 months, hemoglobin level increased by 1.98 ± 2.74 g/dL in the NHHD group while it decreased by 0.20 ± 2.32 g/dL in the CHD group (P = 0.007). ESA requirement decreased by 53.49 ± 55.50 U/kg/week in NHHD patients whereas it increased by 16.22 ± 50.01 U/kg/week in CHD patients (P < 0.001). Twenty‐six percent of NHHD patients were able to stop ESA compared with none in the CHD group. Standard Kt/V showed greater increase in the NHHD group. (1.49 ± 0.36 in NHHD vs. 0.18 ± 0.31 in CHD, P = 0.005). NHHD with an alternate night schedule improves anemia and reduces ESA requirement as a result of enhanced uremic clearance. This benefit extended beyond the first year of NHHD.     

Genetic polymorphisms and the risk of progressive renal failure in elderly Hungarian patients

The relationship between renal disease progression and genetic polymorphism of enzymes influencing endothelial function remains incompletely understood. We genotyped three cohorts of elderly Hungarian patients: 245 patients with end‐stage renal disease (ESRD) on chronic hemodialysis (HD), 88 patients with mild chronic kidney disease (CKD), and 200 healthy controls. The underlying diagnoses of renal diseases were primary glomerulonephritis, interstitial nephritis, hypertension, diabetic nephropathy, and hereditary diseases. We examined genetic polymorphisms of eight candidate genes associated with endothelial function: endothelial constitutive nitric oxide synthase (ecNOS) T‐786C, endothelin‐1 G5727T, methylenetetrahydrofolate reductase (MTHFR) C677T, paraoxonase‐1 Q192R and M55L, angiotensinogen M235T, angiotensin‐converting enzyme (ACE) I/D and angiotensin II type 1 receptor A1166C gene. Six gene polymorphisms were detected by real‐time polymerase chain reaction with melting‐point analysis, and two via allele‐specific amplification and gel electrophoresis. Control group patients were in Hardy‐Weinberg equilibrium for all tested genotypes. In ESRD patients attributed to hypertension, the endothelin gene G5727T GG genotype occurred significantly less but GT genotype more frequently (P < 0.01 for both). In ESRD patients attributed to primary glomerulonephritis, more ACE DD and less ID genotypes were found (P < 0.02 for both) than in the controls. The underlying diagnosis may modify the association of genetic polymorphism and dialysis‐dependent ESRD.     

The Clinical Impact of Increasing the Hemodialysis Dose

Good evidence suggests that improvements in dialysis efficiency reduce morbidity and mortality of hemodialysis (HD) patients. Dialysis efficiency has also been related to better control of arterial blood pressure (BP), anemia, and serum phosphorus levels, and to improvement in patients' nutritional status. Over a 2‐year period, the present self‐controlled study of 34 HD patients (23 men, 11 women; age, 52.6 ± 14.5 years; HD duration, 55.9 ± 61.2 months) looked at the effect on clinical and laboratory parameters of increasing the delivered dialysis dose under a strict dry‐weight policy. Dialysis dose was increased without increasing dialysis time and frequency. A statistically significant increase was seen in delivered HD dose: the urea reduction ratio (URR) increased to 60% ± 10% from 52% ± 8%, and then to 71% ± 7% (p < 0.001); Kt/V_urea increased to 1.22 ± 0.28 from 0.93 ± 0.19, and then to 1.55 ± 0.29 (p < 0.001). A statistically significant increase in hemoglobin concentration also occurred—to 10.8 ± 1.9 g/dL from 10.4 ± 1.7 g/dL, and then to 11.0 ± 1.3 g/dL (p < 0.05 as compared to baseline)—with no significant difference in weekly erythropoietin dose. Statistically significant decreases occurred in the systolic and diastolic blood pressures during the first year; they then remained unchanged. Systolic blood pressure decreased to 131 ± 23 mmHg from 147 ± 24 mmHg (p < 0.001); diastolic blood pressure decreased to 65 ± 11 mmHg from 73 ± 12 mmHg (p < 0.001). Serum albumin increased insignificantly to 4.4 ± 0.4 g/dL from 4.3 ± 0.4 g/dL, and then significantly to 4.6 ± 0.3 g/dL (p = 0.002 as compared to both previous values). Normalized protein catabolic rate increased significantly to 1.16 ± 0.15 g/kg/day from 0.93 ± 0.16 g/kg/ day (p < 0.001), and then to 1.20 ± 0.17 g/kg/day (p < 0.001 as compared to baseline). We conclude that the increases achieved in average Kt/V_urea per hemodialysis session by increasing dialyzer membrane area, and blood and dialysate flows, without increasing dialysis time above 4 hours, in patients hemodialyzed thrice weekly, coupled with strict dry‐weight policy, resulted in improvements in hypertension, nutritional status, and anemia.