Renal replacement therapy modalities and techniques in intensive care units: An international survey

Up to 14 % of critically ill patients receive renal replacement therapy (RRT) during their ICU stay and are treated with intermittent hemodialysis (IHD) or one of the continuous renal replacement therapy (CRRT) techniques. The choice of a modality (IHD or CRRT) and technique (continuuous veno-venous -hemodialysis (CVVHD), -hemofiltration (CVVH), or - hemodiafiltration (CVVHDF)), and the way it is delivered, may have an impact on outcomes but only few studies addressed this question. We aimed to survey the availability, settings, and clinicians' preferences regarding RRT modalities and techniques in critically ill patients.

Between July 2021 and March 2022, we conducted an open online worldwide survey targeting ICU clinicians and consisting of 31 questions.

Among the 1174 participants from 73 countries, 94 % indicated their ability to initiate RRT at any time. CRRT was more widely available than IHD (97 % vs 85 %). CVVHDF was the most frequently used CRRT technique (59 %), followed by CVVHD (26 %) and CVVH (16 %). Most participants (70 %) reported having access to at least two CRRT techniques in their unit. Preference for IHD or CRRT varied greatly, depending on the clinical situation. Among CRRT techniques, CVVHD was preferred for removal of small-sized molecules, better hemofilter lifespan and reduced nursing workload. The preferential indications for CVVH included septic shock, removal of middle-sized molecules and fluid overload. The technical settings for CVVH and CVVHDF were very heterogeneous.

This international survey underscores the large diversity in RRT practices wordlwide, as well as heterogeneity in beliefs and preferences among intensivists. These data highlight the need for robust comparative trials to identify the optimal RRT modality and technique to improve outcomes in specific clinical situations.