Is extracellular volume expansion of peritoneal dialysis patients associated with greater urine output?

Abstract

Background and objectives: Residual renal function (RRF) is important for peritoneal dialysis (PD) technique failure and patient survival. Reduction in extracellular water (ECW) has been reported to reduce urine output. We audited volume status and RRF to determine whether ECW was linked to urinary output.

Methods: We retrospectively audited PD patients who had RRF and multiple frequency bioimpedance spectroscopy assessments.

Results: 550 patients were studied. Urine output was lower in males (p = 0.021), non-Caucasoids (p = 0.04), those prescribed antihypertensives (p < 0.001), and greater glucose dialysate usage (p < 0.001). Urine output was negatively associated with dialysis vintage (F = 40.7, β -0.627, p < 0.001), and ECW (F = 33.7, β -0.177, p < 0.001) and positively associated with intracellular volume (F = 34.6, β 0.11, p < 0.001).

Conclusions: RRF is important for successful PD, and ECW volume expansion may lead to better preservation of RRF in PD patients compared to haemodialysis. However, in our retrospective cross-sectional study, ECW expansion was associated with reduced urine output.