Frequent Hemodialysis Research Articles

Pro: Should we move to more frequent haemodialysis schedules?

Most end-stage renal disease patients on maintenance haemodialysis follow the typical schedule of three sessions per week, and thus remain outside dialysis for two short intervals (∼2 days in duration) and for a longer interval (∼3 days) at the end of each week. This pattern was historically enforced more due to calendar logistics and less due to factors related to health and disease. Therefore, it is long hypothesized that the intermittent nature of haemodialysis and the consequent shifts and fluctuations in volume status and metabolic parameters during the dialysis-free periods may pre-dispose patients to several complications. Recent large-scale observational studies in haemodialysis patients link the first week-day (including the last hours of the long interval and the subsequent dialysis session) with increased risk of cardiovascular morbidity and mortality. Previous observational studies support that enhanced-frequency home haemodialysis is associated with reduced risk of all-cause mortality, while randomized studies suggest that short-daily or alternate-day in-centre haemodialysis offer improvements in left ventricular hypertrophy, blood pressure, phosphorous homeostasis and other intermediate end points when compared with conventional thrice-weekly in-centre haemodialysis. This article summarizes available evidence relating long inter-dialytic intervals with elevated cardiovascular risk, potential mechanisms for this association and the main benefits of more frequent dialytic modalities.

Nephrology Crosswords: Hemodialysis

ACROSS 1 These dialysis membranes clear 10–20 kDa solutes and have a pore size of 3–6 nm. (8) 3 Low concentrations of potassium and ____ have been associated with sudden cardiac death in dialysis patients. (7) 8 This alternate form of anticoagulation on hemodialysis has been speculated to worsen secondary hyperparathyroidism. (7) 10 This large randomized trial showed that statins had no reduction in either overall or cardiovascular mortality in patients with chronic kidney disease who reached end-stage renal disease. (5) 12 In the Frequent Hemodialysis Network trial that looked at in-center hemodialysis six times per week versus three times per week, the group that had more frequent dialysis had more ___ related complications. (6) 13 After initiating dialysis, the mortality is the highest in the first ___ weeks. (3) 14 This uremic toxin is toxic to endothelium and leads to vasculogenesis. (12) DOWN 1 ____ impairs the absorption and recycling of iron and inhibits the proliferation of erythroid progenitor cells. (8) 2 This landmark trial showed that patients undergoing hemodialysis thrice weekly appear to have no major benefit from a higher dialysis dose than that recommended by current U.S. guidelines or from the use of a high-flux membrane. (4) 4 Frequency ____ of dialysis and membrane type are important considerations for removal of low-molecular-weight uremic toxins. (6) 5 Low ____ concentrations have been shown to be associated with symptomatic or asymptomatic intradialytic hypotension. (9) 6 Based on the European Best Practice Guidelines, the minimum frequency and dose of dialysis is ___ hours per treatment three times per week for most patients. (4) 7 Relative plasma volume may be a useful technique to assess __ _____ among hypertensive hemodialysis patients. (9) 9 The most common cause of end-stage kidney disease in the United States. (8) 11 Dialysate ____ is a potential culprit substance that leads to intradialytic hypotension. (7) 12 This uremic protein-bound toxin reduces nitric oxide synthesis and provokes an increase in systemic vascular resistance and hypertension. (Abbrv) (4) http://www.kidney-international.org m a k e y o u r d i a g n o s i s

Circulating Endotoxaemia and Frequent Haemodialysis Schedules

Background/Aims: Endotoxaemia, a driver of systemic inflammation, appears to be driven by dialysis-induced circulatory stress in haemodialysis (HD) patients. More frequent HD regimens are associated with lower ultrafiltration requirements, improved haemodynamic stability and lower systemic inflammation. This study investigated the hypothesis that more frequently dialysed patients, with reduced exposure to dialysis-induced haemodynamic perturbation, would have lower circulating endotoxin (ET) levels. Methods: A cross-sectional study of 86 established HD patients compared three groups: conventional HD 3× per week (HD3, n = 56), frequent HD 5-6× per week (SDHD, n = 20), and nocturnal HD (NHD, n = 10). Data collection included ultrafiltration volume and rate, serial blood pressures and blood sampling with quantification of ET, troponin T and high-sensitivity CRP (hsCRP). Results: Pre-dialysis serum ET was highest in the conventional HD group (HD3 0.66 ± 0.29 EU/ml vs. NHD 0.08 ± 0.04 EU/ml). Across the study population, severity of endotoxaemia was associated with higher ultrafiltration rates, degree of intradialytic hypotension, troponin T and hsCRP levels. NHD patients had the lowest ultrafiltration requirements, the greatest haemodynamic stability and lower ET levels. Conclusion: More frequent HD regimens are associated with lower levels of circulating ET compared with conventional HD. Reduced ET translocation may be related to the greater haemodynamic stability of these treatments, with superior maintenance of splanchnic perfusion.

Agreement of Single- and Multi-Frequency Bioimpedance Measurements in Hemodialysis Patients: An Ancillary Study of the Frequent Hemodialysis Network Daily Trial

Background: Bioimpedance analysis (BIA) is well established to assess body composition. Agreements between single- and multi-frequency bioimpedance (SF-BIA, MF-BIS) measurements in subjects undergoing 6 or 3 times/week hemodialysis (HD) were analyzed. Methods: Total body water (TBW) and intra- and extracellular fluid (ICF, ECF) of subjects enrolled in the Frequent Hemodialysis Network (FHN) Daily Trial (www.clinicaltrials.gov No. NCT00264758) were measured with a Hydra 4200 at baseline (BL) and at 5 months (M5). Volumes were computed using SF (at 50 kHz) and MF approaches. Agreement was assessed by means of linear regression and Bland-Altman analysis and treatment effects by t test. Results: 35 subjects (17 on the more frequent regimen, 26 males, 20 African-American, 48 ± 9 years, pre-HD weight 84 ± 19 kg) were studied. Assessments with SF-BIA and MF-BIS correlated significantly at BL and M5 in both arms. No proportional errors, but systematic biases over the entire range of values were found at BL and M5. Agreement did not differ between subjects randomized to either HD treatment arm at both time points. MF-BIS appears to have better precision than SF-BIA allowing the observation of a significant treatment effect by the intervention [-1.5 (95% CI -2.5 to -0.5) l] on ECF, not found for ECF SF-BIA. Precision also affected the statistical power of the SF-BIA data in the current analysis. Conclusion: Both methods showed agreement without significant proportional errors regardless of HD frequency and can be used for longitudinal analyses. SF-BIA has lower precision which needs thorough consideration in the design of future trials with similar outcomes.

Frequent Hemodialysis Fistula Infectious Complications

Background: Few studies have examined if infectious arteriovenous access complications vary with the cannulation technique and whether this is modified by dialysis frequency. We compared the infection rate between fistulas cannulated using buttonhole versus stepladder techniques for patients treated with short daily (SDH) or nocturnal hemodialysis at home (NHD). We also compared patients receiving conventional intermittent hemodialysis (CIHD) using stepladder cannulation. Methods: Data were prospectively collected from 631 patients dialyzed with a fistula from 2001 to 2010 (Toronto and Ottawa, Canada). We compared the person-time incidence rate of bacteremia and local fistula infections using the exact binomial test. Results: Forty-six (7.3%) patients received SDH (≥5 sessions/week, 2-4 h/session), 128 (20.3%) NHD (≥4 sessions/week, ≥5 h/session) and 457 (72%) CIHD (3 sessions/week, ≤4 h/session). Fifty percent of SDH and 72% of NHD patients used the buttonhole technique. There were 39 buttonhole-related bacteremias (rate: 0.196/1,000 fistula days) and at least 2 local buttonhole site infections. Staphylococcus aureus accounted for 85% of the bacteremias. There were 5 (13%) infection-related hospitalizations and 3 (10%) serious metastatic infections, including fistula loss. In comparison, there was 1 possible fistula-related infection in CIHD during follow-up (rate: 0.002/1,000 fistula days). Conclusions: The rate of buttonhole-related infections was high among patients on frequent hemodialysis and more than 50 times greater than that among patients on CIHD with the stepladder technique. Most bacteremias were due to S. aureus - with serious consequences. The risks and benefits of buttonhole cannulation require individual consideration with careful monitoring, prophylaxis and management.

Intestinal adsorption of uraemic toxins: a new strategy for anaemia management?

1. Blagg CR. The 50th anniversary of long-term hemodialysis: University of Washington Hospital, March 9th, 1960. J Nephrol 2011; 24(Suppl 17): S84–S88 2. National Kidney Foundation I, Kidney Disease Dialysis Outcome Quality Initiative. K/doqi clinical practice guidelines for hemodialysis adequacy. Am J Kidney Dis 1998 3. European best practice guidelines expert group on haemodialysis. Nephrol Dial Transplant 2002; 17(Suppl 7): S16–S31 4. Eknoyan G, Beck GJ, Cheung AK et al. Effect of dialysis dose and membrane flux in maintenance hemodialysis. N Engl J Med 2002; 347: 2010–2019 5. Chertow GM, Levin NW, Beck GJ et al. In-center hemodialysis six times per week versus three times per week. N Engl J Med 2010; 363: 2287–2300 6. Daugirdas JT, Greene T, Rocco MV et al. Effect of frequent hemodialysis on residual kidney function. Kidney Int 2013; 83: 949–958 7. Bieber B, Qian J, Anand S et al. Two-times weekly hemodialysis in China: frequency, associated patient and treatment characteristics and Quality of Life in the China Dialysis Outcomes and Practice Patterns study. Nephrol Dial Transplant 2014; 29: 1770–1777 8. Rhee CM, Unruh M, Chen J et al. Infrequent dialysis: a new paradigm for hemodialysis initiation. Semin Dial 2013; 26: 720–727 9. Kovesdy CP, Kalantar-Zadeh K. Enter the dragon: a Chinese epidemic of chronic kidney disease? Lancet 2012; 379: 783–785 10. Zhang L, Wang F, Wang L et al. Prevalence of chronic kidney disease in China: a cross-sectional survey. Lancet 2012; 379: 815–822 11. Molnar MZ, Ojo AO, Bunnapradist S et al. Timing of dialysis initiation in transplant-naive and failed transplant patients. Nat Rev Nephrol 2012; 8: 284–292 12. Rhee CM, Kalantar-Zadeh K. Transition to dialysis: controversies in its timing and modality. Introduction. Semin Dial 2013; 26: 641–643 13. Kalantar-Zadeh K, Unruh M, Zager PG et al. Twice-weekly and incremental hemodialysis treatment for initiation of kidney replacement therapy. Am J Kidney Dis 2014 (in press) 14. Ghaffari A, Kalantar-Zadeh K, Lee J et al. Pd first: peritoneal dialysis as the default transition to dialysis therapy. Semin Dial 2013; 26: 706–713 15. Casino FG. The grey line of dialysis initiation: as early as possible that is, by the incremental modality. G Ital Nefrol 2010; 27: 574–583

Let us give twice-weekly hemodialysis a chance: revisiting the taboo.

Let us give twice-weekly hemodialysis a chance: revisiting the taboo.

Effects of frequent hemodialysis on perceived caregiver burden in the Frequent Hemodialysis Network trials.

Patients receiving hemodialysis often perceive their caregivers are overburdened. We hypothesize that increasing hemodialysis frequency would result in higher patient perceptions of burden on their unpaid caregivers. In two separate trials, 245 patients were randomized to receive in-center daily hemodialysis (6 days/week) or conventional hemodialysis (3 days/week) while 87 patients were randomized to receive home nocturnal hemodialysis (6 nights/week) or home conventional hemodialysis for 12 months. Changes in overall mean scores over time in the 10-question Cousineau perceived burden scale were compared. In total, 173 of 245 (70%) and 80 of 87 (92%) randomized patients in the Daily and Nocturnal Trials, respectively, reported having an unpaid caregiver at baseline or during follow-up. Relative to in-center conventional dialysis, the 12-month change in mean perceived burden score with in-center daily hemodialysis was -2.1 (95% confidence interval, -9.4 to +5.3; P=0.58). Relative to home conventional dialysis, the 12-month change in mean perceived burden score with home nocturnal dialysis was +6.1 (95% confidence interval, -0.8 to +13.1; P=0.08). After multiple imputation for missing data in the Nocturnal Trial, the relative difference between home nocturnal and home conventional hemodialysis was +9.4 (95% confidence interval, +0.55 to +18.3; P=0.04). In the Nocturnal Trial, changes in perceived burden were inversely correlated with adherence to dialysis treatments (Pearson r=-0.35; P=0.02). Relative to conventional hemodialysis, in-center daily hemodialysis did not result in higher perceptions of caregiver burden. There was a trend to higher perceived caregiver burden among patients randomized to home nocturnal hemodialysis. These findings may have implications for the adoption of and adherence to frequent nocturnal hemodialysis.

Cognitive impairment in chronic kidney disease: keep vascular disease in mind

Cognitive impairment is a major cause of morbidity in people with chronic kidney disease (CKD) and is associated with lower quality of life, more difficulty adhering to medications, and worse survival. Prior data suggest a relationship between vascular disease and cognitive impairment in individuals with CKD, although overall risk factors remain poorly understood. Critically, clinicians should be aware of the high rates of cognitive impairment that occur in all stages of CKD, which, although sometimes subtle, may impact comprehension and decision making in these individuals and may herald future, more debilitating impairment.

Vascular access‐related infection in nocturnal home hemodialysis

Frequent hemodialysis is associated with increased vascular access adverse events. We hypothesized that bacteremia would be more frequent in patients with central venous catheter (CVC) than arteriovenous fistula or arteriovenous graft (AVF/AVG) in nocturnal home hemodialysis (NHHD). We reviewed blood culture reports and concurrent clinical data for a cohort of one hundred eighty-seven NHHD patients between January 1, 2006 and June 30, 2012. The primary outcome was time to first bacteremia, technique failure, or death after commencing NHHD. Types of bacteremia and clinical consequences were analyzed. Analyses were adjusted for a priori defined confounders. One hundred eighty-seven patients were included with a total follow up of six hundred five patient years. Initial vascular access was AVF in seventy-eight (42%) patients, AVG in eleven (6%) patients, and CVC in ninety-eight (52%) patients. A total of 79.3% of patients with a CVC reached the composite endpoint of bacteremia, technique failure, or death in the study period; 44.5% of patients with an AVF or AVG reached this composite endpoint. Adjusted time to first bacteremia, technique failure, or death was significantly shorter in patients with initial CVC access (hazard ratio 2.42, 95% confidence interval 1.50-3.90, p < 0.001). Risk factors for bacteremia were comorbid status quantified by the Charlson Comorbidity Index (p < 0.001) and diabetes (p < 0.001). Coagulase negative staphylococcus was the commonest organism cultured accounting for 51.4% bacteremias. The second commonest organism was staphylococcus aureus (20.3% bacteremias). Patients undergoing NHHD with a CVC have a shorter duration to first infection, technique failure, or death than those with permanent vascular access.

Nocturnal Home Hemodialysis Associates with Improvement of Electrocardiographic Features Linked to Sudden Cardiac Death

Sudden cardiac death (SCD) remains the leading cause of death in hemodialysis patients. We performed a retrospective electrocardiograph (ECG) and chart review to determine whether hemodialysis modality, frequency, or duration could predict change in ECG parameters associated with SCD. Frequent nocturnal hemodialysis was associated with an improvement in Tpeak to Tend within 365 days (83.8-71.8 ms, p = 0.005) and past 365 days of dialysis initiation (85.9-77.1 ms, p = 0.005) and improvement in QRS amplitude variation within 365 days (0.0583-0.0297, p = 0.025) and past 365 days of dialysis initiation (0.0546-0.0332, p = 0.029). Compared with intermittent conventional hemodialysis, more frequent nocturnal (15/25 vs. 3/14, p = 0.04) and intermittent nocturnal hemodialysis (INHD) (6/8 vs. 3/14, p = 0.03) patients decreased Tpeak to Tend. More short-hours daily than INHD patients increased T-wave amplitude variation (16/25 vs. 1/8, p = 0.02). These improvements occurred before changes in Cornell or Sokolow-Lyon electrocardiographic left ventricular mass. Thus, it appears that hemodialysis modalities of longer duration are associated with improvements in electrocardiographic parameters associated with SCD. Prospective trials are required to determine whether dialysis prescription reduces SCD, cardiovascular morbidity, and mortality in hemodialysis patients.

Blood thiol status and erythrocyte glutathione-S-transferase in chronic kidney disease patients on treatment with frequent (daily) hemodialysis

Background. Chronic kidney disease (CKD) is a condition of impaired homeostasis of blood thiols characterized by a severe hyperhomocysteinemia (HH) and abnormal expression of the red blood cell glutathione (GSH)-consuming enzyme GSH S-transferase (eGST) (Galli et al., Clin Chem 1999). The correlation between plasma Hcy and eGST recently identified by our group (Dessì et al., Amino Acids 2012) suggests a role of this detoxifying enzyme in the impaired thiol status of CKD treated with hemodialysis therapy (HD). This retrospective study is aimed at investigating whether frequent HD can alleviate these biochemical symptoms of CKD. Methods. Laboratory data of a population of 98 HD patients investigated for plasma Hcy and blood thiol status between 1999 and 2004 were examined. A frequent HD method carried out with a 2-h daily schedule (daily HD) (DHD) was compared with standard 4-h × 3/week protocol of HD (SHD) in either cross-sectional (n = 70 SHD vs. n = 28 DHD) and prospective A-B design (n = 18 SHD patients shifted to DHD). Results. The results demonstrate that DHD produces a better correction than SHD of the uremic retention solute Hcy as well as of Cys and Cys-Gly measured in plasma. Such a correction effect of DHD on HH correlates with that on the detoxification enzyme eGST and on pGSH. Conclusions. These findings point to a role of frequent dialysis in the depuration of uremic retention solutes that may interfere with thiol metabolism and redox in HD patients. These solutes may include substrates of eGST that await further investigation for molecular identification and better removal by more efficient dialysis therapies.

Hemodialysis: Core Curriculum 2014

From the Division of Nephrology and Hypertension, Vanderbilt University Medical Center, Nashville, TN. Received May 1, 2013. Accepted in revised form July 1, 2013. Originally published online November 21, 2013. Address correspondence to Thomas A. Golper, MD, S3303 Medical Center North, Vanderbilt University Medical Center, 21st Ave S, Nashville, TN 37232. E-mail: thomas.golper@vanderbilt. edu 2013 by the National Kidney Foundation, Inc. 0272-6386/$36.00 http://dx.doi.org/10.1053/j.ajkd.2013.07.028 PRINCIPLES OF DIALYSIS AND HOW MODALITIES DIFFER

Economic Evaluation of Frequent Home Nocturnal Hemodialysis Based on a Randomized Controlled Trial

Provider and patient enthusiasm for frequent home nocturnal hemodialysis (FHNHD) has been renewed; however, the cost-effectiveness of this technique is unknown. We performed a cost-utility analysis of FHNHD compared with conventional hemodialysis (CvHD; 4 hours three times per week) from a health payer perspective over a lifetime horizon using patient information from the Alberta NHD randomized controlled trial. Costs, including training costs, were obtained using microcosting and administrative data (CAN$2012). We determined the incremental cost per quality-adjusted life year (QALY) gained. Robustness was assessed using scenario, sensitivity, and probabilistic sensitivity analyses. Compared with CvHD (61% in-center, 14% satellite, and 25% home dialysis), FHNHD led to incremental cost savings (-$6700) and an additional 0.38 QALYs. In sensitivity analyses, when the annual probability of technique failure with FHNHD increased from 7.6% (reference case) to ≥19%, FHNHD became unattractive (>$75,000/QALY). The cost/QALY gained became $13,000 if average training time for FHNHD increased from 3.7 to 6 weeks. In scenarios with alternate comparator modalities, FHNHD remained dominant compared with in-center CvHD; cost/QALYs gained were $18,500, $198,000, and $423,000 compared with satellite CvHD, home CvHD, and peritoneal dialysis, respectively. In summary, FHNHD is attractive compared with in-center CvHD in this cohort. However, the attractiveness of FHNHD varies by technique failure rate, training time, and dialysis modalities from which patients are drawn, and these variables should be considered when establishing FHNHD programs.

The Effects of Frequent Hemodialysis on Left Ventricular Mass, Volumes, and Geometry

Left ventricular (LV) remodeling is defined as ‘‘the genomic expression resulting in molecular, cellular, and interstitial changes that are manifested clinically as changes in size, shape, and function of the heart after cardiac injury” ([1][1]). In ESRD, LV remodeling manifests features of

ECG Machine QTc Intervals Are Inaccurate in Hemodialysis Patients

Background: Nephrologists need effective screening tools to identify hemodialysis patients at elevated risk for sudden cardiac death, the leading cause of death in this population. QTc intervals longer than 450 ms in males and 470 ms in females, measured by the gold standard tangent method (trueQTc), are prolonged and increase sudden cardiac death in healthy populations and patients with long QT syndrome. Methods: We performed a retrospective ECG and chart review of hemodialysis patients. Our first objective was to determine if machine-measured QTc intervals (macQTc) could be used to identify dialysis patients with prolonged trueQTc. Our second objective was to determine at what macQTc could prolonged trueQTc be confidently diagnosed. Results: macQTc differed from the trueQTc by an average of 16.54 ms, and by at least 20 ms in 46.8, 36.1, 53.6, 50.0 and 57.1% of all, short-hours daily hemodialysis, intermittent conventional hemodialysis, frequent nocturnal hemodialysis and intermittent nocturnal hemodialysis patients, respectively. The positive predictive value, negative predictive value, sensitivity and specificity of prolonged macQTc predicting prolonged trueQTc was 57.6, 92.6, 79.1 and 81.8%, respectively. Thus, macQTc is inaccurate at predicting the gold standard trueQTc in hemodialysis patients. macQTc greater than 480 ms in hemodialysis patients predicts trueQTc prolongation with a positive predictive value of 95.2%, but with a low sensitivity of 32.3%. Conclusion: In hemodialysis patients, ECG macQTc intervals are insufficiently sensitive or specific to predict prolonged trueQTc intervals, unless >480 ms.

Determinants of phosphorus mobilization during hemodialysis

Our recent work proposed a pseudo one-compartment model for describing intradialysis and postdialysis rebound kinetics of phosphorus. In this model, phosphorus is removed directly from a central distribution volume with the rate of phosphorus mobilization from a second, very large compartment proportional to the phosphorus mobilization clearance. Here, we evaluated factors of phosphorus mobilization clearance and postdialysis central distribution volume from 774 patients in the HEMO Study. Phosphorus mobilization clearance and postdialysis central distribution volume were 87 (65, 116) ml/min, median (interquartile range), and 9.4 (7.2, 12.0) liter, respectively. The phosphorus mobilization clearance was significantly higher for male patients than for female patients. Both the phosphorus mobilization clearance and the postdialysis central distribution volume were significantly associated with postdialysis body weight but negatively with the predialysis serum phosphorus concentration. The postdialysis central distribution volume was also significantly associated with age. Overall, the postdialysis central distribution volume was 13.6% of the postdialysis body weight. Thus, the phosphorus mobilization clearance during hemodialysis is higher when predialysis serum phosphorus concentration is low and higher in male patients than in female patients. The central distribution volume of phosphorus is a space approximating the extracellular fluid volume.

Effects of daily hemodialysis on heart rate variability: results from the Frequent Hemodialysis Network (FHN) Daily Trial.

End-stage renal disease is associated with reduced heart rate variability (HRV), components of which generally are associated with advanced age, diabetes mellitus and left ventricular hypertrophy. We hypothesized that daily in-center hemodialysis (HD) would increase HRV. The Frequent Hemodialysis Network (FHN) Daily Trial randomized 245 patients to receive 12 months of six versus three times per week in-center HD. Two hundred and seven patients had baseline Holter recordings. HRV measures were calculated from 24-h Holter electrocardiograms at both baseline and 12 months in 131 patients and included low-frequency power (LF, a measure of sympathetic modulation), high-frequency power (HF, a measure of parasympathetic modulation) and standard deviation (SD) of the R-R interval (SDNN, a measure of beat-to-beat variation). Baseline to Month 12 change in LF was augmented by 50% [95% confidence interval (95% CI) 6.1-112%, P =0.022] and LF + HF was augmented by 40% (95% CI 3.3-88.4%, P = 0.03) in patients assigned to daily hemodialysis (DHD) compared with conventional HD. Changes in HF and SDNN were similar between the randomized groups. The effects of DHD on LF were attenuated by advanced age and diabetes mellitus (predefined subgroups). Changes in HF (r = -0.20, P = 0.02) and SDNN (r = -0.18, P = 0.04) were inversely associated with changes in left ventricular mass (LVM). DHD increased the LF component of HRV. Reduction of LVM by DHD was associated with increased vagal modulation of heart rate (HF) and with increased beat-to-beat heart rate variation (SDNN), suggesting an important functional correlate to the structural effects of DHD on the heart in uremia.

Dialysis Initiation: What's the Rush?

The recent trend to early initiation of dialysis (at eGFR >10 ml/min/1.73 m(2) ) appears to have been based on conventional wisdoms that are not supported by evidence. Observational studies using administrative databases report worse comorbidity-adjusted dialysis survival with early dialysis initiation. Although some have concluded that the IDEAL randomized controlled trial of dialysis start provided evidence that patients become symptomatic with late dialysis start, there is no definitive support for this view. The potential harms of early start of dialysis, including the loss of residual renal function (RRF), have been well documented. The rate of RRF loss (renal function trajectory) is an important consideration for the timing of the dialysis initiation decision. Patients with low glomerular filtration rate (GFR) may have sufficient RRF to be maintained off dialysis for years. Delay of dialysis start until a working arterio-venous access is in place seems prudent in light of the lack of harm and possible benefit of late dialysis initiation. Prescribing frequent hemodialysis is not recommended when dialysis is initiated early. The benefits of early initiation of chronic dialysis after episodes of congestive heart failure or acute kidney injury require further study. There are no data to show that early start benefits diabetics or other patient groups. Preemptive start of dialysis in noncompliant patients may be necessary to avoid complications. The decision to initiate dialysis requires informed patient consent and a joint decision by the patient and dialysis provider. Possible talking points for obtaining informed consent are provided.

Infrequent Dialysis: A New Paradigm for Hemodialysis Initiation

Nearly a half-century ago, the thrice-weekly hemodialysis schedule was empirically established as a means to provide an adequate dialysis dose while also treating the greatest number of end-stage renal disease (ESRD) patients using limited resources. Landmark trials of hemodialysis adequacy have historically been anchored to thrice-weekly regimens, but a recent randomized controlled trial demonstrated that frequent hemodialysis (six times per week) confers cardiovascular and survival benefits. Based on these collective data and experience, clinical practice guidelines advise against a less than thrice-weekly treatment schedule in patients without residual renal function, yet provide limited guidance on the optimal treatment frequency when substantial native kidney function is present. Thus, during the transition from Stage 5 chronic kidney disease to ESRD, the current paradigm is to initiate hemodialysis on a "full-dose" thrice-weekly regimen even among patients with substantial residual renal function. However, emerging data suggest that frequent hemodialysis accelerates residual renal function decline, and infrequent regimens may provide better preservation of native kidney function. Given the high mortality rates during the first 6 months of hemodialysis and the survival benefits of preserved native kidney function, initiation with twice-weekly treatment schedules ("infrequent hemodialysis") with an incremental increase in frequency over time may provide an opportunity to optimize patient survival. This review outlines the clinical benefits of post-hemodialysis residual renal function, studies of twice-weekly treatment regimens, and the potential risks and benefits of infrequent hemodialysis.