Most continuous renal replacement therapy (CRRT) filter sets are designed for a maximum runtime of 72 h according to the manufacturer. A new filter set (OMNIset Pro® version 3.10) with an approved maximum runtime of 96 h has been proposed but has never been formally tested in critically ill patients. We conducted a single-center prospective observational study to compare the performance of the new dialyzer with the previous generation and to assess the feasibility and efficacy of extending therapy up to 96 h in circuits that remains patent. Between January 2022 and February 2023 (period 2), we used the new OMNIset Pro® (version 3.10) in all patients admitted to our unit who required CRRT with the OMNI® (B Braun). Circuits lasting less than 24 h were excluded. We measured urea, creatinine, β2-microglobulin (ß2MG), and albumin levels in both plasma and effluent at 12, 24, 48, 72 and 96 h after circuit initiation. We computed effluent serum ratios (ESR) and clearances normalized to body mass for these molecules and compared results to similar measurements performed in patients admitted between September and December 2020 (period 1) who received CRRT using the old OMNIset Pro® (version 3.0). Comparisons were performed using mixed-models statistical analyses. We included 42 circuits in 17 patients during period 1 and 50 circuits in 23 patients during period 2. Median lifespan was similar in both periods (57 h (IQR: 42–68) for period 1 and 50 h (IQR: 37–83) for period 2, p = 0.77). In period 2, 12 (24%) filters remained patent up to the 96 h limit. Median ESR for urea, creatinine and albumin were similar between the two periods. The ESR for creatinine presented a slight decrease over time of similar magnitude in both periods. The ESR for ß2MG remained stable for 96 h but was significantly lower in period 2 compared to period 1. New dialyzer enabled fluid removal and allowed rapid and sustained normalization of serum potassium and sodium levels, as well as metabolic acidosis. Among circuits running ≥ 24 h, the new filter set showed similar solute clearance performance to the previous generation. In circuits that remained patent, sustained clearance was observed up to 96 h.
Ahmad et al. (Tue,) studied this question.