Survival with short-daily hemodialysis: association of time, site, and dose of dialysis.

In thrice-weekly hemodialysis, survival correlates with the length of time (t) of each dialysis and the dose (Kt/V), and deaths occur most frequently on Mondays and Tuesdays. We studied the influence of t and Kt/V on survival in 262 patients on short-daily hemodialysis (SDHD) and also noted death rate by weekday. Contingency tables, Kaplan-Meier analysis, regression analysis, and stepwise Cox proportional hazard analysis were used to study the associations of clinical variables with survival. Patients had been on SDHD for a mean of 2.1 (range 0.1-11) years. Mean dialysis time was 12.9 ± 2.3 h/wk and mean weekly stdKt/V was 2.7 ± 0.5. Fifty-two of the patients died (20%) and 8-year survival was 54 ± 5%. In an analysis of 4 groups by weekly dialysis time, 5-year survival continuously increased from 45 ± 8% in those dialyzing <12 hours to 100% in those dialyzing >15 hours without any apparent threshold. There was no association between Kt/V and survival. In Cox proportional hazard analysis, 4 factors were independently associated with survival: age in years Hazard Ratio (HR)=1.05, weekly dialysis hours HR=0.84, home dialysis HR=0.50, and secondary renal disease HR=2.30. Unlike conventional HD, no pattern of excessive death occurred early in the week during SDHD. With SDHD, longer time and dialysis at home were independently associated with improved survival, while Kt/V was not. Homedialysis and dialysis 15+ h/wk appear to maximize survival in SDHD.

Short daily haemodialysis: survival in 415 patients treated for 1006 patient-years.

BACKGROUND: Survival statistics for daily haemodialysis are lacking as most centres providing this have treated only a small number of patients for short observation times. We pooled our 23-year, 1006-patient-year, five-centre experience of 415 patients treated by short daily haemodialysis. METHODS: One hundred and fifty patients were treated in-centre, most because of medical complications and 265 by home or self-care haemodialysis. Patients were on daily haemodialysis for 29 +/- 31 (0-272) months. Forty-two percent had primary and 31% had secondary renal failure. Treatment time was 136 +/- 35 min, frequency 5.8 +/- 0.5 times/week and weekly stdKt/V 2.7 +/- 0.55. RESULTS: Eighty-five patients (20%) died; 5-year cumulative survival was 68 +/- 4.1% and 10-year survival was 42 +/- 9%. Age, secondary renal failure and in-centre dialysis were associated with mortality, while gender, frequency of dialysis (5, 6 or 7 per week), continent, country and blood access were not. Survival was compared with matched patients from the USRDS 2005 Data Report using the standardized mortality ratio and cumulative survival curves. Both comparisons showed that the survival of the daily haemodialysis patients was 2-3 times higher and the predicted 50% survival time 2.3-10.9 years longer than that of the matched US haemodialysis patients. Survival of patients dialyzing daily at home was similar to that of age-matched recipients of deceased donor renal transplants. CONCLUSIONS: Survival of patients on short daily haemodialysis was 2-3 times better than that of matched three times weekly haemodialysis patients reported by the USRDS.

A new procedure allowing the complete removal and prevention of hemodialysis biofilms.

Most currently used disinfectants for dialysis machines have a good bactericidal efficacy on biofilms but leave dead cells on the surface. This contributes to the regrowth of biofilm and the release of pyrogens. A new anti-biofilm procedure consisting of sequential treatment combining enzymes and detergents is able to detach adherent cells. The efficacy of this procedure was assessed both in vitro and in reality. For in vitro studies, a biofilm model was set up. Studies were also performed in reality in a clinically used dialysis machine. Biofilm removal was first monitored by image analysis. Then, the biomass was detached by scraping and quantified by plate counts and endotoxin level measurement. Treated samples were compared to untreated control samples. The procedure led to the complete detachment of the biomass, both in vitro and in the reality situation. The aim of this procedure is to replace or complete the usual disinfection methods for medical devices.

Short daily hemodialysis and nutritional status in patients with chronic renal failure.

Malnutrition is a frequent complication in hemodialysis patients and is associated with increased mortality and morbidity. Interventions such as oral or intravenous nutritional supplements have often failed to improve nutritional status. We report here the effect that daily dialysis, practiced in our center since 1997, has had on nutritional parameters. Seventeen patients treated with conventional hemodialysis (4-5 hours, three times per week, for 9.6 +/- 8.4 years) were converted to short daily hemodialysis (2-2.5 hours, six times per week, for a mean of 39.1 +/- 23.5 months). Dietary, anthropometric, and biochemical evaluations were performed during conventional hemodialysis, after 1 year on short daily hemodialysis (sDHD(year)), and at the end of follow-up (sDHD(end)). Daily protein intake increased from 1.21 +/- 0.27 g/kg/day with conventional hemodialysis to 1.51 +/- 0.47 g/kg/day at sDHD(year) and 1.51 +/- 0.37 g/kg/day at sDHD(end). Energy intake increased from 33.6 +/- 9.5 kcal/kg/day to 38.3 +/- 10.9 kcal/kg/day at sDHD(year) and 39.4 +/- 9.4 kcal/kg/day at sDHD(end). The normalized protein equivalent nitrogen appearance (nPNA) increased from 1.19 +/- 0.34 g/kg/day with conventional hemodialysis to 1.34 +/- 0.43 g/kg/day sDHD(year) and 1.37 +/- 0.37 g/kg/day sDHD(end). Biochemical indicators also increased: serum albumin increased from 40.2 +/- 3.3 g/L to 44.5 +/- 4.6 g/L and 45.1 +/- 4.1 g/L, and prealbumin increased from 0.32 +/- 0.06 g/L to 0.38 +/- 0.09 g/L and 0.36 +/- 0.09 g/L, respectively. These improvements were accompanied by an increase in body weight from 62.0 +/- 10.6 kg on conventional hemodialysis to 64.3 +/- 10.2 kg at sDHD(year) and 65.5 +/- 9.7 kg at sDHD(end). All the changes between conventional hemodialysis and short daily hemodialysis were statistically significant. Increased frequency is more important than increased dialysis dose. Short daily hemodialysis appears to be a suitable method to improve nutritional status in dialysis patients.

Six years' experience with short daily hemodialysis: do the early improvements persist in the mid and long term?

Observational studies from several groups have shown consistent beneficial effects in patients treated with short daily hemodialysis (SDHD). The cardiovascular and nutritional changes appear during the first few months after the initiation of SDHD. An extensive review of 17 patients from a group of 36 ESRD patients treated for up to 6 years with SDHD was undertaken to compare the clinicobiologic results during the initial period of standard hemodialysis (3 x 4 hr/week) and the short daily hemodialysis period at 1 year (SDHD(1)) and subsequent years (SDHD(2)). The statistical analysis of the clinicobiologic data clearly shows that the initial favorable results obtained during the first year of SDHD do persist in the mid and long term, which shows the more physiologic nature of this dialytic approach. The amelioration of left ventricular hypertrophy is of particular interest, showing a regression of ventricular dilation during the first year followed by a reduction of interventricular septum and posterior wall thickness during the subsequent years.

Daily Hemodialysis versus Standard Hemodialysis: TAC, TAD, Weekly eKt/V, std(Kt/V), and PCRn.

Seven patients, mean age 42.57 ± 15.69 years (range 21 - 67 years), on standard hemodialysis (SHD), 4 - 5 hours, three times per week for 11.0 ± 6.63 years (range 1 - 18 years), were switched to daily hemodialysis (DHD), 2 - 2.5 hours, six times per week. For each type of treatment similar parameters were applied, and the total weekly time was the same. Mean duration of DHD was 15.4 ± 4.98 months (range 7 - 20 months). We report here our results of quantification in each method, including time-averaged concentration (TAC), normalized protein catabolic rate (PCRn), equilibrated Kt/V (eKt/V), equivalent normalized continuous standard clearance [std(Kt/V)], equivalent renal urea clearance (eKRn), and time-averaged deviation (TAD). With DHD, urea TAC was reduced from 19.09 ± 3.47 to 15.16 ± 3.21 mmol/L (p = 0.026), urea TAD diminished from 4.76 ± 1.04 to 2.52 ± 0.57 mmol/L (p = 0.000 53), PCRn increased from 1.11 ± 0.23 to 1.42 ± 0.24 g/kg/day (p = 0.001), weekly eKt/V increased from 4.11 ± 0.31 to 4.74 ± 0.43 (p = 0.000 25), std(Kt/V) rose from 2.17 ± 0.06 to 4.02 ± 0.25 (p = 0.0001), and eKRn increased from 12.96 ± 0.60 to 21.7 ± 3.09 mL/min (p = 0.000 45). On DHD the most important quantitative variation is the decrease of urea TAD (closer to that of a healthy kidney), due to the increased frequency of dialysis; std(Kt/V) practically doubled and represents 30% of that of normal renal function. These changes are probably the main explanation for the clinical improvements, but it is difficult to dissociate the effects of increased dialysis dose from the effects of decreased TAD.

Time Needed to Improve Clinical Parameters By Daily Hemodialysis.

Daily hemodialysis therapy (DHD), 2 hours, 6 times per week, is able to cure complications that persist on standard hemodialysis (SHD), 4 hours, 3 times per week. Cardiovascular manifestations (high blood pressure, left ventricular hypertrophy), nutritional deficient states, and postdialysis asthenia are improved during the first month of DHD therapy and are usually cured at 3 months. Daily hemodialysis may be considered as a rescue therapy. The next step will be to select which patients can return to the classical SHD therapy without recurrence of their complications.