Water treatment-free prolonged intermittent kidney replacement therapy: A new approach for kidney replacement therapy in the ICU setting. A retrospective study

Abstract

The optimal modalities of kidney replacement therapy (KRT) in the ICU remain debated. Intermittent haemodialysis (IHD) and continuous veno-venous haemofiltration (CVVH) are the two main methods. Intermittent haemodialysis requires a water treatment system, which may not be available in all jurisdictions. We report the experience of an innovative strategy of intermittent KRT without water treatment system. Based on the manufacturer's recommendations, the dialysate flow during "CVVHDF post" (post-dilution continuous veno-venous haemodiafiltration) mode was increased by connecting the substitution pump in parallel with the dialysate pump using a Y-connector. This doubled the flow rate of dialysate, allowing for 9000 mL/h during intermittent KRT sessions at a blood flow rate of 250 mL/min. We called this technique "water treatment-free prolonged intermittent kidney replacement therapy" (WTF-PIKRT). We report our experience in 18 patients who underwent 88 WTF-PIKRT sessions (median duration 5 h (IQR [4, 6])) between August 2019 and May 2020. The median urea reduction ratio was 38 % (IQR [29,49]). Hypotension occurred during 21.6 % of sessions. Hypokalemia or hypophosphatemia occurred in less than 5 % of sessions. WTF-PIKRT represents an attractive alternative to conventional IHD when a water treatment system is not available. Despite its lower efficacy compared with IHD, it may have significant organizational and economic impact.

Keywords: Intermittent haemodialysis; Kidney replacement therapy; Renal replacement therapy; Urea reduction ratio; Veno-venous haemofiltration; Water purification; Water treatment.