How important is volume control in Peritoneal Dialysis
How important is volume control in patients treated with PD, and how is it best managed?
Attainment of euvolemia has been demonstrated to be important to clinical outcome in patients with ESKD, whether treated with PD or HD.
Although determination of dry weight is challenging for any patient, observational analyses have demonstrated that enhanced UF in patients treated with PD is associated with improved survival.
Conservative management is the cornerstone of volume management and includes kidney protective measures, sodium restriction, and optimal use of diuretics. Peritoneal UF using icodextrin (Extraneal) is superior to dextrose-based solutions for the long dwell exchange (8 to 16 hours). Icodextrin also removes greater amounts of sodium per volume of ultrafiltrate than dextrose-based solutions (i.e., 130 mEq/L vs. 100 mEq/L of UF, respectively) related to its mechanism of action. Specifically, Icodextrin is an iso-osmolar solution that acts exclusively on the small pores of the peritoneal capillaries, drawing near isotonic ultrafiltrate (by colloid osmosis) into the peritoneal cavity from the blood. Conversely, nearly half of ultrafiltrate obtained by dextrose-based solutions (crystalloid osmosis) is sodium-free water derived from the osmolality-sensitive aquaporins. The use of icodextrin also simplifies the PD prescription, as UF and sodium removal with icodextrin is relatively independent of patient transport type ( Fig. 53.3 ). It also helps reduce peritoneal glucose exposure and systemic glucose absorption, particularly for fast and fast average transport patients.