A Detailed Analysis Of Clinical Measurement Error In Ultrafiltration In Peritoneal Dialysis

Abstract BackgroundIt has been noticed for years that ultrafiltration is important for survival in peritoneal dialysis. On the other hand, ultrafiltration measurement is much more complicated than it thought to be. Both overfill and flush before fill used to be source of measurement error. However, controversy finding around ultrafiltration in peritoneal dialysis still exists.MethodsFour different brands of dialysate were purchased from the market. The freshest dialysate available in the market were intentionally picked. The dialysate were all 2L, 2.5% dextrose and traditional lactate buffered PD solution. They were stored in four different conditions with controlled temperature and humidity. The bags were weight at baseline, 6 months and 12 months of storage. Specific gravity was measured in mixed 24 hour drainage dialysate from 261 CAPD patients in a cross sectional manner. ResultsThere was significant difference in dialysate bag weight at baseline between brands. The weight declined significantly after 12 months storage. The weight loss was more significant in higher temperature and lower humidity. The dialysate in non-PVC package lose less weight than PVC package. The specific gravity of dialysate drainage was significantly higher than pure water and related to dialysate protein concentration.ConclusionStorage condition and duration, as well as the type of the dialysate package gave extra variance in overfill volume. The fact that specific gravity of dialysate drainage is higher than 1g/ml also contributes to systemic measurement error of ultrafiltration in manual exchanges.Trial Registration: ClinicalTrials.gov ID: NCT03864120 (March 8, 2019) (Understand the Difference Between Clinical Measured Ultrafiltration and Real Ultrafiltration)