Hydration status does not influence peritoneal equilibration test ultrafiltration volumes.
ABSTRACT The peritoneal equilibration test (PET) was developed some 25 yr ago and has been used to help prescribe peritoneal dialysis. However, PET is affected by several factors, including diabetes and inflammation. It was speculated that extracellular fluid overload would increase PET ultrafiltration volumes, and therefore the usefulness of the PET in routine clinical practice was audited.
Data from 211 consecutive patients attending a university teaching hospital for a standard PET who had multifrequency bioimpedance performance were analyzed to determine which factors affected net PET ultrafiltration volumes.
Net PET ultrafiltration volume was independent of gender, age, diabetes, residual renal function, peritoneal dialysis prescriptions (modes and dialysates), extracellular fluid volume, or C-reactive protein (CRP). There was an inverse regression with serum albumin and sodium on multiple logistical regression analysis (F = 13.4, P < 0.001 and F = 10.1, P = 0.001, respectively) and a positive regression with 24-h net peritoneal ultrafiltration volumes (F = 15.5, P < 0.001). As expected, there was a strong correlation with net sodium losses (r = 0.99, P < 0001).
It was found that PET test ultrafiltration volume in routine clinical practice was not affected by CRP, hyperglycemia, or extracellular fluid volume overload. Ultrafiltration volumes were increased in those patients with reduced serum sodium and albumin, most likely because of inflammation and protein malnutrition.
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ABSTRACT: The development of fluid and salt retention is a potential problem for all peritoneal dialysis (PD) patients. Sodium removal by the peritoneum is predominantly determined by convective fluid loss but influenced by diffusion and sieving due to free water transport as predicted by the three-pore model (TPM). The aim of the study was to establish the effect of transport status, dwell length and glucose concentration on observed ultrafiltration (UF), dialysate sodium concentration ([Na(+)](D)) and removal, and compare this with that predicted by a computer program based on the principles of the TPM. This was a cross-sectional study of UF and [Na(+)](D) collected prospectively from dwells classified by length, glucose concentration and membrane transport characteristics. Solute transport, converted to area parameter and UF capacity, was measured on each occasion by the peritoneal equilibration test. These parameters, along with plasma [Na(+)], were entered into the computer model. Fixed values for other parameters, e.g. hydraulic conductance and lymphatic absorption and sump volume, were used. A total of 1853 dwells from 182 patients [10% were on automated PD (APD)] were analysed. There was a high degree of correlation (r = 0.83-95, P<0.001) between the observed and predicted values for UF, [Na(+)](D) and sodium removal across the full range of dwell categories. The model overpredicted UF as the net volume increased with increasing glucose concentration, independently of solute transport. This bias was not fully explained by the preferential use of hypertonic dialysate by patients with reduced UF capacity. The prediction of [Na(+)](D) described sodium sieving, which was overestimated in a small number of patients with UF failure. There were no discrepancies between continous ambulatory PD (CAPD) and APD patients. This analysis endorses the TPM as a description of membrane function, particularly in relation to sodium sieving and removal. The relationship between dialysate glucose concentration and achieved UF appears to be more complex; even accounting for extended time on treatment and reduction in the osmotic conductance in patients preferentially using hypertonic exchanges, further adjustments may be needed to account for the tendency to overestimate UF.Nephrology Dialysis Transplantation 06/2005; 20(6):1192-200. · 3.37 Impact Factor
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ABSTRACT: The mortality rate of peritoneal dialysis (PD) patients is still high and controversies persist regarding the mortality predictor. This study was designed to identify the predictability of the extracellular water/intracellular water ratio (E/I) on mortality in PD patients. 227 incident PD patients were included. Time-dependent Cox proportional hazard regression was used to investigate the predictability of E/I on mortality. The 2- and 3-year survival was 74 and 65%, respectively. Univariate Cox proportional hazard regression analysis showed that the significant predictors of mortality were age, sex, Charlson Comorbidity Index, total Kt/V, serum albumin, pulse pressure, presence of malnutrition, and E/I. However, the final Cox proportional hazard models revealed that E/I was the only significant predictor. For every increase of 0.1 in the E/I value, the relative risk of death was 1.368. E/I is a strong independent predictor of mortality in incident PD patients.Blood Purification 02/2007; 25(3):260-6. · 2.06 Impact Factor
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ABSTRACT: Cardiovascular morbidity and mortality is increased in diabetic haemodialysis patients. Diabetic subjects may suffer greater thirst and thereby be predisposed to increased interdialytic weight gains and hypertension. 175 established adult diabetic haemodialysis patients attending outpatient haemodialysis thrice weekly were audited during a 1-week interval. Despite fewer patients prescribed antihypertensive medications (46%), the mean pre-dialysis systolic blood pressure was lowest in those patients with the lowest HbA1c values (<or=6%; 146 +/- 27 mm Hg), versus 154 +/- 25 mm Hg for the highest group, with a HbA1c of >8%, of whom 70% were prescribed antihypertensive medications (p < 0.05). Both absolute and percentage interdialytic weight gain was lowest in the group with the best diabetic control: 2.0 +/- 1 kg and 2.76 +/- 1.5% versus 2.5 +/- 1.1 kg and 3.3 +/- 1.3%, respectively (p < 0.05). Poor diabetic control may increase thirst and salt intake, leading to increased interdialytic weight gains, associated with systolic hypertension, and as such, diabetic control is an important facet in the management of the diabetic haemodialysis patient.Nephron Clinical Practice 07/2009; 113(1):c33-7. · 1.65 Impact Factor