Figure 2.

Plasma amino acids and effluent loss during different modes of renal replacement therapy (RRT). Plasma (a,c,e) and effluent (b,d,f) were sampled before, at the end, and 1 to 2 hours after the end of each RRT session. α-Amino acids (×20 standard proteogenic plus a further 18 amino acids) were measured after deproteinization and derivatization using a Biochrom 20 (Biochrom, Cambridge, UK). Data (mean ± SE) are presented corrected (i.e., included as covariates in the statistical model) for dose-of-dialysis (urea reduction ratio for plasma levels; solute removal index for effluent losses) and plasma concentration (for calculation of effluent losses only). If necessary, to normalize residual error before statistical analysis, data were log₁₀ transformed. Graphs were generated in GraphPad Prism 6 (GraphPad Software Inc., San Diego, CA). Analysis was by repeated-measures analysis of variance or mixed-effect models, as appropriate, with RRT mode and time as fixed effects and patient ID as a nested random effect, using Genstat v18 (VSNi, Rothampsted, UK). Statistical significance was accepted at P < 0.05. CVVH, continuous veno-venous hemofiltration; IHD, intermittent hemodialysis; SLEDf, sustained low-efficiency diafiltration.