Comparative Study between Classic and Newer Methods for the Evaluation of Hemodialysis Adequacy

Aim:  The comparative study of hemodialysis (HD) adequacy of Kt/V measurement between classic method (Daugirdas formula) and urea sensor monitor (online).
Patients and methods:  30 patients with end-stage renal failure undergoing dialysis were studied. A comparative evaluation of HD adequacy during the same session was done with two different methods: (1) blood samples were drawn in the beginning and in the end of HD session for the measurement of blood urea nitrogen (BUN) and after measurement of HD adequacy by 3rd generation Daugirdas formula and (2) urea sensor monitor use for continuous HD adequacy measurement during HD session.
Results:  There was statistically significant correlation of Kt/V Daugirdas with Kt/V online (r = 0.8, p < 0.001). Also there was statistically significant correlation between solute removal index (SRI), Kt/V Daugirdas (r = 0.81, p < 0.001) and Kt/V online (r = 0.92, p < 0.001). From nutrition indices that were measured, the protein catabolic rate (PCR) had marginal negative correlation with the two compared adequacy indices, Kt/V Daugirdas (r = −0.24, p < 0.03), and Kt/V online (r = −0.17, p < 0.03) although the nPCR (normalized PCR) had marginal positive correlation (r = 0.35, p < 0.05) (r = 0.42, p < 0.05).
Conclusions:  The use of online urea sensor monitors contributes to the easy measurement of adequacy and nutrition indices and hence complicated mathematical formulas are not necessary. The results of these measurements are reliable and comparable with classic methods of HD adequacy evaluation.     

Gender,low Kt/V,and mortality in Japanese hemodialysis patients: Opportunities for improvement through modifiable practices

Guidelines have recommended single pool Kt/V > 1.2 as the minimum dose for chronic hemodialysis (HD) patients on thrice weekly HD. The Dialysis Outcomes and Practice Patterns Study (DOPPS) has shown that “low Kt/V” (<1.2) is more prevalent in Japan than many other countries, though survival is longer in Japan. We examined trends in low Kt/V, dialysis practices associated with low Kt/V, and associations between Kt/V and mortality overall and by gender in Japanese dialysis patients. We analyzed 5784 HD patients from Japan DOPPS (1999–2011), restricted to patients dialyzing for >1 year and receiving thrice weekly dialysis. Logistic regression models estimated the relationships of patient characteristics with Kt/V. Logistic models also were used to estimate the proportion of low Kt/V cases attributable to various treatment practices. Multivariable Cox regression was used to estimate the associations of low Kt/V, blood flow rate (BFR), and treatment time (TT), with all‐cause mortality. From 1999 to 2009, the prevalence of low Kt/V declined in men (37–27%) and women (15–10%). BFR <200 mL/min, TT <240 minutes, and dialyzate flow rate (DFR) < 500 mL/min were common (35, 13, and 19% of patients, respectively) and strongly associated with low Kt/V. Fifteen percent of low Kt/V cases were attributable to BFR <200 and 13% to TT <240, compared to only 3% for DFR <500. Lower Kt/V was associated with elevated mortality, more so among women (hazard ratio [HR] = 1.13 per 0.1 lower Kt/V, 95% CI: 1.07–1.20) than among men (HR = 1.06 per 0.1 lower Kt/V, 95% CI: 1.00–1.12). The relatively large proportion of low Kt/V cases in Japanese facilities may potentially be reduced 30% by increasing BFR to 200 mL/min and TT to 4 hours thrice weekly in HD patients. Associations of low Kt/V with elevated mortality suggest that modification of these practices may further improve survival for Japanese HD patients.     

Choice Reaction Time and Adequacy of Dialysis: A New Application of an Old Method

Background:  Choice Reaction Time (CRT) is the time it takes for a subject to accurately respond to a flashing panel of lights. The CRT has been used to assess the quality of dialysis in hemodialysis patients and to assess the neurological impairments in patients with Parkinson's disease.
Methods:  Three groups of end‐stage renal disease (ESRD) patients on three different renal replacement therapies were tested using CRT: intermittent peritoneal dialysis (IPD, n = 11), thrice weekly hemodialysis (HD, n = 22), and well‐functioning kidney transplant (Tx, n = 6). A group of volunteers with normal renal function (NL, n = 12) was also tested.
Results:  The CRT was significantly longer in IPD patients (618 ± 89 ms) than observed in the other three groups (p < 0.0001). CRT in HD patients was 461 ± 50 ms, which was significantly longer than in Tx patients (396 ± 25 ms, p = 0.05). However, the CRT in the Tx patients was no different from the NL (382 ± 22, p = 0.32). There was a strong negative correlation between CRT and weekly creatinine clearance in the IPD group (r =− .96) and between the dialysis index and CRT in HD (r =− 0.79).
Conclusions:  CRT may be a useful tool in assessing the adequacy of dialysis.     

On‐line Haemodiafiltration in the Management of Acute Renal Failure

Dialysis adequacy targets are frequently difficult to achieve in large hemodialysis patients. Dual dialyzers can be used to improve clearance. It is unknown whether series or parallel configurations are superior. Objective: to improve urea clearance in large patients using parallel and series dual dialyzers. Patients and Methods: Eighteen large hemodialysis patients (mean 92.4 kg) were enrolled in a randomized, crossover trial to directly compare dual dialyzers in parallel and series configurations. Treatments times, blood flow rates, and dialysate flow rates were kept constant. Results: Compared to single dialyzers, parallel dual dialyzers increased the spKt/V from 1.25 +/− 0.22 to 1.43 +/− 0.29 (p < 0.003). Series dual dialyzers improved the spKt/V to 1.46 +/− 0.26 (p < 0.0003 compared to single dialyzer). The Kt/V and URR of dual dialyzers in parallel were not significantly different from dual dialyzers in series. Half of the subjects failed to meet the NKF‐K/DOQI recommended adequacy target of spKt/V urea >/= 1.2 using a single dialyzer. With the use of dual dialyzers 83% of subjects achieved this adequacy target. Serum levels of 'middle molecule,' beta‐2 microgobulin, were reduced 34% after two months of dual dialyzer therapy. Cost analysis estimates annual net savings of $1260 with dual dialyzer therapy, primarily from projected savings in inpatient expenses. Conclusions: In large hemodialysis patients, our study demonstrates that dual dialyzers in parallel and series are equally effective in improving urea clearance without prolonging dialysis treatment times.     

Nocturnal Home Hemodialysis: Patient''s Perspective

Purpose:  Quality of life (QoL) is a well-recognized important measure of therapy outcome, as it reflects what patients perceive as their health condition. The aim of this study was to estimate the QoL in patients on HD and to find the factors that mainly affect it.
Patients and Methods:  We studied 70 patients on HD (38 male, age 57.86 ± 14.63 years) with the use of kidney disease quality of life short form. Physical health (PH), mental health (MH), kidney disease issues (KDIs), and patient satisfaction (PS) were assessed, as well as Khan comorbidity index, adequacy of dialysis, nutrition, and epidemiologic and laboratory data.
Results:  PH was significantly correlated with comorbidity (p < 0001), age (p < 0001), duration of HD (p < 0001), serum albumin (Salb) (p < 0005), the existence of a living relative donor (p < 0001), Hb (p < 0.01), and CRP (p < 0.01). MH was significantly correlated to comorbidity (p < 0001), age (p < 0001), duration of HD (p < 0001), Salb (p = 0002), the existence of a living relative donor (p < 0001) and Hb (p < 0.01). KDI score was significantly correlated with comorbidity (p < 0001), age (p < 0001), duration of HD (p < 0001), and Hb (p < 0.05). The acceptance of the method was significantly lower in patients with AVF dysfunction (p < 0005). As much as 44.3% of patients presented inadequate compliance to dietary and fluid restrictions.
Conclusion:  Frequent QoL assessment in patients on HD is a useful tool for professionals involved in patients' care. Older age, long time on HD, malnutrition, elevated CRP, and comorbid conditions are correlated to lower QoL scores.     

Half the V by 120: A practical approach to the prevention of the dialysis disequilibrium syndrome

The dialysis disequilibrium syndrome (DDS) results from osmotic shifts between the blood and the brain compartments. Patients at risk for DDS include those with very elevated blood urea nitrogen, concomitant hypernatremia, metabolic acidosis, and low total body water volumes. By understanding the underlying pathophysiology and applying urea kinetic modeling, it is possible to avoid the occurrence of this disorder. A urea reduction ratio (URR) of no more than 40%–45% over 2 h is recommended for the initial hemodialysis treatment. The relationship between the URR and Kt/V is useful when trying to model the dialysis treatment to a specific URR target. A simplified relationship between Kt/V and URR is provided by the equation: Kt/V = −ln (1 − URR). A URR of 40% is roughly equivalent to a Kt/V of 0.5. The required dialyzer urea clearance to achieve this goal URR in a 120-min treatment can simply be calculated by dividing half the patient's volume of distribution of urea by 120. The blood flow rate and dialyzer mass transfer coefficient (K₀A) required to achieve this clearance can then be plotted on a nomogram. Other methods to reduce the risk of DDS are reviewed, including the use of continuous renal replacement therapy.     

Changes of Plasma Amino Acid Profile in Hemodialysis Patients

Background:  The aim of this study was to investigate the influence of HCV on two markers of systemic inflammation, serum CRP, and interleukin-6 (IL-6) in HD patients.
Methods:  The study included 118 HD patients (47% males, age 47 ± 13 years, 9% diabetics) who were treated by on standard HD for at least 6 months. The patients were divided in two groups, depending on the presence (HCV+) or absence (HCV–) of serum antibodies against HCV. Serum albumin (S-Alb), plasma high sensitivity CRP (hsCRP), IL-6, and alanine aminotransferase (ALT) were measured, and the values were compared with 22 healthy controls.
Results:  The median of hsCRP, IL-6, and the hsCRP/IL-6 ratio were: 3.5 vs. 2.1 mg/L, p < 0.05; 4.3 vs. 0.9 pg/mL, p < 0.0001; and 0.8 vs. 2.7 pg/mL, p < 0.0001 for patients and controls, respectively. Age, gender, S-Alb, IL-6, and hsCRP did not differ between the HCV+ and HCV– patients. However, HCV+ patients had higher ALT (29 ± 21 vs. 21 ± 25 UI/L) and had been a longer time on HD (6.1 ± 3.0 vs. 4.0 ± 2.0 years) (p < 0.0001), respectively. Moreover, HCV+ patients had a significantly lower median hsCRP/IL-6 ratio (0.7 vs. 0.9; p < 0.05) as compared to the HCV group.
Conclusion:  The finding that the hsCRP/IL-6 ratio was lower in HCV+ patients than in HCV– patients suggests that hsCRP may be a less useful marker of inflammation in HCV+ patients and that a different cut-off value for hsCRP may be required to define inflammation in HD patients.     

Compliance, quality of life, and contributing factors in renal transplantation waiting list patients

Poor patient compliance is common during dialysis therapy. We aimed to study incidence of noncompliance, contributing factors, and effects on quality of life (QOL) among cadaveric renal transplantation waiting list patients. We included 86 renal transplantation waiting list patients (56M/30F). Dialysis duration, previous renal transplantation history, comorbid conditions, interdialytic weight gain, predialysis BUN, creatinine, potassium, and phosphate were recorded. Noncompliance criteria were skipping >1 dialysis session or shortening a dialysis session>10 min in 1 month, interdialytic weight gain>5.7% of body weight, predialysis serum potassium >6 mEq/L, and phosphate level >7.5 mg/dl. There were 49 noncompliant (age: 46.8 ± 21.8 years, HD duration: 83.9 ± 48.7 months) and 37 compliant (age: 42.8 ± 12.1 years, HD duration: 96.5 ± 45.2 months) patients. QOL was evaluated by short form 36 and depression levels by Beck Depression Inventory. Previous renal transplantation was present in 24.4% and comorbid diseases in 31.3% of all patients. In depressed patients, 77.8% had comorbid diseases. No difference was found between the groups considering age, gender, dialysis duration, previous transplantation history, and comorbid diseases (p > 0.05). Noncompliant patients had lower QOL (p < 0.04). Noncompliant patients had higher degree of depression (p = 0.01). QOL and Beck scores were negatively correlated (p = 0.001, r = −0.561). Noncompliance to diet and dialysis therapy is associated with depression, which further decreases QOL in renal transplantation waiting list patients. Early diagnosis of depression, is possible by monitoring noncompliance, and therapeutic intervention may benefit during the transplantation‐waiting period.     

Solute kinetics with short-daily home hemodialysis using slow dialysate flow rate

"NxStage System One^™" is increasingly used for daily home hemodialysis. The ultrapure dialysate volumes are typically between 15 L and 30 L per dialysis, substantially smaller than the volumes used in conventional dialysis. In this study, the impact of the use of low dialysate volumes on the removal rates of solutes of different molecular weights and volumes of distribution was evaluated. Serum measurements before and after dialysis and total dialysate collection were performed over 30 times in 5 functionally anephric patients undergoing short-daily home hemodialysis (6 d/wk) over the course of 8 to 16 months. Measured solutes included β₂ microglobulin (β₂M), phosphorus, urea nitrogen, and potassium. The average spent dialysate volume (dialysate plus ultrafiltrate) was 25.4±4.7 L and the dialysis duration was 175±15 min. β₂ microglobulin clearance of the polyethersulfone dialyzer averaged 53±14 mL/min. Total β₂M recovered in the dialysate was 106±42 mg per treatment (n=38). Predialysis serum β₂M levels remained stable over the observation period. Phosphorus removal averaged 694±343 mg per treatment with a mean predialysis serum phosphorus of 5.2±1.8 mg/dL (n=34). Standard Kt/V averaged 2.5±0.3 per week and correlated with the dialysate-based weekly Kt/V. Weekly β₂M, phosphorus, and urea nitrogen removal in patients dialyzing 6 d/wk with these relatively low dialysate volumes compared favorably with values published for thrice weekly conventional and with short-daily hemodialysis performed with machines using much higher dialysate flow rates. Results of the present study were achieved, however, with an average of 17.5 hours of dialysis per week.     

Intensive In-Center Hemodialysis for Children: A Case for Longer Dialysis Duration

Background:  Children with renal failure need their dialysis time optimized. Although traditional surrogate markers of outcome in pediatric patients have been growth and development, increasing attention is being focused on cardiovascular risk factors, such as hypertension, volume overload, malnutrition, and elevated calcium (Ca) and phosphorus (P) levels. We have previously shown catch-up growth without growth hormone, in children undergoing long intermittent hemodialysis. Recently we analyzed retrospectively cardiovascular risk factors in patients treated with this regimen.
Methods:  Patients starting dialysis between 1997 and 2001 and on dialysis at least 6 months were evaluated. Charts were reviewed for Ca, P, parathyroid hormone (PTH), albumin, hemoglobin and blood pressure levels, Ca intake, blood pressure medications, dialysis time, and clearance and ultrafiltration rates. Means were calculated for 6- month intervals, up to 36 months.
Results:  Mean equilibrated dialyzer Kt/V _urea ranged from 1.9 to 2.1, and mean weekly dialysis time for oliguric patients varied from 14.8 to 16.3 hr, with average hourly ultrafiltration rates from 0.3 to 0.4 L. Mean values for P and Ca × P were below 1.8 mM and 4.4 mmol   ² /L ² , respectively. Mean hemoglobin levels were 115 to 126 g/L, albumin 39 to 41 g/L, and PTH 156 to 231 pg/mL. Most patients had normal predialysis blood pressures.
Conclusions:  In this pediatric cohort, intensive center hemodialysis was associated with excellent growth, nutrition, Ca, P, and anemia control and reasonable blood pressure values. Large multicenter studies are needed to better determine optimal dialysis therapy for children.     

The Effect of Frequent and Occasional Dialysis-Associated Hypotension on Survival of Patients on Hemodialysis

Hyperphosphatemia and poor uremia control are established cardiovascular risk factors in patients with end-stage renal disease (ESRD) associated with impaired endothelial dependent and independent vasodilation (EDV and EIV). Nocturnal hemodialysis [6 × 8 h/week] augments dialysis dose and offers normal phosphate (Pi) balance. We hypothesized that NHD would restore EDV (endothelial function) and EIV (vascular smooth muscle cell function) by simultaneously improving uremia and Pi control. 2 groups of ESRD patients (mean age 41 ± 2 years) stratified according to their baseline plasma Pi levels (normal Pi <1.8 mM, high Pi >1.8 mM) were studied. Dialysis dose (Kt/V per session), plasma Pi, blood pressure (BP) and brachial artery responses to reactive hyperemia (EDV), and sublingual nitroglycerin (EIV) were examined before, 1 and 2 months after conversion from conventional hemodialysis (CHD) [3 × 4 h/week] to NHD. After 2 months, NHD increased dialysis dose (from 1.24 ± 0.06 to 2.04 ± 0.08; p = 0.02) and lowered BP (from 140 ± 5/82 ± 3 to 119 ± 1/71 ± 3, p = 0.01) in all patients. In patients with adequate Pi control during CHD, EDV was normalized after 1 month of NHD. In contrast, in the high Pi group, 1 month of NHD was sufficient to reduce plasma phosphate levels, but 2 months of NHD was required for EDV to improve.  

     

Mini mental status examination (MMSE) in stable chronic renal failure patients on hemodialysis: The effects of hemodialysis on the MMSE score. A prospective study

Cognitive impairment is common in hemodialysis (HD) patients. The mini mental status examination is a simple screening test for dementia. The objectives of this study were to (1) study and compare the predialysis and postdialysis mini mental status examination score and 2 subscores and compare them with those of a control group and (2) determine the factors affecting these scores. This was a prospective study of 54 HD patients, which involved calculation of their predialysis (PrHDSc) and (2–4 weeks later) postdialysis (PoHDSc) scores and comparison of these with the control scores (CoSc). The mean scores for PreHDSc and PoHDSc were 26.5±2.7 and 26.4±3.3, respectively. Both were significantly lower than CoSc, 28.4±1.6 (95% CI for score difference 0.99–2.97, P<0.001). The subscores for orientation, registration, and recall (ORR) and attention (ATT) before and after HD were 14.2±1.3, 14.3±1.8, and 3.5±1.7, 3.2±1.8, respectively. Both were significantly lower than the CoSc, 15.2±1.2 and 4.2±1.1 (P=0.001 and 0.004, respectively). There were no significant differences between the PrHDSc and PoHDSc (P values of 0.87, 0.63, and 0.45, respectively). Patients' PrHDSc correlated positively with PoHDSc and dialysis efficiency measured by the urea reduction ratio and Kt/V (r=0.58, 0.4, and 0.34, respectively). Education level correlated positively with PrHDSc r=0.41 but not PoHDSc. Hemodialysis duration correlated negatively with PrHDSc r=−0.3. There was no correlation among age, chronic renal failure duration, HD frequency, weight loss, systolic or diastolic blood pressure drop, and PrHDSc or PoHDSc. Hemodialysis patients scored significantly less than the control patients. Their score was not affected by HD. This may reflect the stable cognitive function/dysfunction or the mild sensitivity of the test.     

Accuracy of Doppler Ultrasonography in Measuring Radial Artery Wall Thickness in Hemodialysis Patients: Comparison with Histologic Examination

Increased radial artery wall thickness (RAWT) is considered to be associated with early failure of radiocephalic arteriovenous fistula (AVF) as well as coronary artery atherosclerosis in hemodialysis patients. Therefore, exact measurement of RAWT by noninvasive method before the operation is very important.
Objective:  This study was designed to evaluate accuracy of Doppler ultrasonography in measuring RAWT in hemodialysis patients.
Methods:  This study enrolled 21 hemodialysis patients undergoing radiocephalic AVF operation for the first time. We measured RAWT (intima-media thickness) using high-resolution Doppler ultrasonography at the wrist before the AVF operation. We obtained specimens of the radial artery during the AVF operation and then measured RAWT by histologic examination.
Results:  Mean age of the patients was 60 ± 13 years and the number of females was 7 (33.3%). Mean values of RAWT measured by Doppler ultrasonography and histologic examination were 485 ± 93 μm (300–700 μm) and 426 ± 106 μm (300–700 μm), respectively. The value of RAWT of Doppler sonographic measurement well correlated with that of histologic measurement (r = 0.800, p < 0.001).
Conclusion:  Our data suggest that Doppler ultrasonography is an effective tool in measuring RAWT in hemodialysis patients before AVF operation.     

Studies of phosphate dynamics during hemodialysis

Regulation of phosphate (PO₄) in hemodialysis patients is very difficult and ideal levels are rarely maintained. A high removal and a normal phosphate level is important, as high and low levels are both associated with morbidity and a very high mortality.
We studied phosphate dynamics and its relation to other small "uremic" molecules in 48 patients by measuring pre‐ and postdialysis levels and all removed phosphate, urea and creatinine (creat) in all dialysate during 455 dialyses done at different frequencies (freq): 3.7 ± 1.2, range 3–6 treatments per week and durations of dialysis (t): mean: 196 ± 95, range 80–560 min and with high (HF) and low flux membranes.
Kt/V‐PO₄, Kt/V‐urea and Kt/V‐creat, volumes (Vr) for all solutes and their relationships to frequency and duration of dialysis, urea clearance and predialysis phosphate were calculated.  

     

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.     

Return on Investment: An Economic Guideline for Selecting Home Daily/Nocturnal Hemodialysis Patients

One of the main symptoms of terminal-stage chronic renal insufficiency is anemia. One of the best applicable methods correcting anemia is using recombinant human erythropoietin preparation. Using recombinant human erythropoietin in patients with terminal-stage chronic renal insufficiency in 90–95% of events had a positive effect, but 5–10% of patient had refraction to erythropoietin, which has spurred the search for new efficient methods correcting anemia. The purpose of the study was to determine the influence of the laser on erythropoiesis and blood acid–alkaline condition (pH) in patients with terminal-stage chronic renal insufficiency. In the course of the study, erythrocytes, hemoglobin, reticulocytes in blood, and blood acid–alkaline condition (pH) were determined. At the beginning of the treatment, all hematological parameters 5 and 15 days after marrow stimulation were defined. 15 days after marrow stimulation with laser, increasing amounts of erythrocytes, hemoglobin, and hematocrit were observed. The initial erythrocyte count was 2.22 ± 0.1 × 10¹²/L, hemoglobin 67.7 ± 3.2 g/L and hematocrit 18.2 ± 1.2%. During the laser treatment, erythrocyte count increased up to 2.9 ± 0.8 × 10¹²/L, hemoglobin up to 89.6 ± 2.9 g/L and hematocrit up to 28.2 ± 1.3% (p < 0005).     

Dialysis adequacy and nutritional status of hemodialysis patients

To characterize the nutritional status of renal failure patients and its relationship with hemodialysis adequacy measured by Kt/V, a study was carried out with a population of 44 adult patients with renal failure and mean age 51+/-15 years. Anthropometric data, such as dry weight, height, arm circumference, triceps skinfold thickness, mid-arm muscle circumference, and body mass index were assessed, and biochemical tests were conducted for urea, potassium, creatinine, serum albumin, and phosphorus levels, in addition to hemogram and quarterly urea reduction rate average (Kt/V). In order to evaluate calorie intake, a dietary questionnaire on habitual daily food ingestion was administered, taking into consideration the hemodialysis date. The patients were divided into 2 separate groups for the statistical analysis, with 50% of the patients in each group: A (Kt/V<1.2) and B (Kt/V>1.2). The data were tabulated as mean and standard deviation, with differences tested by Student's t test. The correlations between variables were established by the coefficient p of Pearson. Most of the patients (43%) were considered eutrophic, based on the BMI, and presented inadequate calorie intake, corresponding to 88.5+/-24% (30.8 kcal/kg actual weight) of the total energy required and adequate protein intake, reaching 109.9+/-40% of the recommended daily allowance (1.24 g/kg of actual weight). There was a correlation of Kt/V with anthropometric parameters such as body mass index, arm circumference, and mid-arm muscle circumference. The biochemical parameters related to dialysis adequacy were albumin, ferritin, and urea (predialysis). Well-dialyzed patients presented better levels of serum albumin. There was an influence of gender and age on correlations of the analyzed variables. Female and younger patients presented better dialysis adequacy. The dialysis adequacy was related to the nutritional status and influenced by the protein intake and body composition. Gender and age had an important influence in the dialysis adequacy, as men presented lower dialysis adequacy and younger adults presented better dialysis adequacy. Further research is necessary to understand better how to facilitate effective and efficient techniques for the nutritional status assessment of hemodialysis patients.     

A study of 8 hour long night dialysis with the Aksys PHD dialysis system

The Aksys PHD system is designed for short quotidian dialysis employing a 52‐liter batch of ultrapure dialysate and up to 30 in situ hot water reuses of the entire extracorporeal circuit including a 40‐liter physical cleaning before each dialysis. Methods:  We studied the effect of the 52‐liter tank during 108 long 5–8 hour dialysis 3.5–6 times/week in 5 patients and one 50‐liter patient simulator for 4 weeks. Phosphate (PO₄), beta‐2 microglobulin (b‐2), urea (BUN), and creatinine (creat) were measured pre‐, during, and post‐dialysis 86 times and in total dialysate 74 times during long dialysis. Tank saturation, Kt/V, and monthly chemistries were also measured. Results:  Patient weight 76 ± 2 kg, QB 234 ± 23 ml/min, QD 498 ± 13 ml/min. Dialysate was recirculated 4.8 times during 8 hours.