The influence of extracellular fluid volume on serum proteins in peritoneal dialysis patients

Patients on peritoneal dialysis (PD) often present a deficit of serum protein and especially of albumin, due to its loss through the peritoneum and some others factors. Serum albumin is a marker of survival, of nutritional status and is changed in inflammation in renal failure. Correction of the albumin level is difficult and needs a dietary or other supplementation. Some suspicions exist that a reduction exist that a reduction in overhydration in PD patients may improve serum proteins, particularly albumins. The study tries to prove or to deny the thesis, investigating 27 PD patients (cycler PD, CPD) during 6 weeks.

Body weight, blood pressure, total serum protein, albumin, C-reactive protein, 24-h urine and volume of the dialysate solution were measured at the first and the final week. The extracellular fluid volume was evaluated by multiple-frequency bioelectrical impedance. Dialysis prescription was changed between the 0- and 6-week to increase the daily ultrafiltrate volume (1.00+/-0.87 1 to 1.32+/-0.85 1, p<0.05).

There was a significant reduction in body weight (p<0.001), extracellular fluid volume (p<0.001), systolic blood pressure (p<0.001), diastolic blood pressure (p<0.01). Serum albumin increased significantly (p<0.01), there was a trend to augmentation of total protein and C-reactive protein did not change.

The study suggests that overhydration has only a light influence on total serum protein, but impacts significantly the serum albumin level and blood pressure as well. The reduction in body weight can be a helpful way to overcome the hypoalbuminemia and hypertension i.e. to improve the survival time of patients on continuous ambulatory peritoneal dialysis.