Application of body composition monitoring to peritoneal dialysis patients.

Assessment of body fluids in peritoneal dialysis is an important issue in the treatment of renal failure. Overhydration is related with hypertension and left ventricular hypertrophy and dehydration leads to hypotension and reduction of residual renal function. Bioimpedance analysis (BIA) provides objective information in assessment of hydration status of the patients. In the past BIA was not widely used in patients undergoing peritoneal dialysis. Our aim was to estimate the status of hydration in our peritoneal dialysis population by body composition monitoring (BCM) device to modify our pharmacological and dialysis policy. We used a Fresenius Body Composition Monitor, a whole-body bioimpedance spectroscopy (50 frequencies, 5-1,000 kHz ), to assess the body composition of 97 patients on peritoneal dialysis in our center. The patients were subjected to a physical examination every three months: We measured body weight, 24 h diuresis and performed a BIA session. BIA measurements were repeated according to different clinical situations. Every patient underwent BIA at least on two different occasions. Our preliminary results have found a strict correlation between weight increase or decrease and the results (total body water, extracellular water, lean mass index) shown by BCM. Modifications of therapy in patients dehydrated restored a satisfying amount of diuresis. Hypertensive overhydrated patients changed their scheduled treatment improving their blood pressure and achieving a lower body weight. Bio impedance analysis is the most reliable, repetitive, not invasive, simple, portable and relatively inexpensive technique to assess the fluid status of a dialysis patient is bioimpedance.