Protocol synopsis Study title "Low flow" CO2 removal via a membrane gas exchange device (Prismalung®) on a renal replacement platform (Prismaflex®) in hypercapnic, ventilated patients requiring renal replacement therapy Brief description Prismalung Study Indication Hypercapnic, ventilated, and renal replacement therapy requiring patients Primary study goal Changes in the arterial pCO2 value Secondary study goals Changes in the acid-base balance Changes of tidal volumes/ventilation pressures Changes in hemodynamics Study design Prospective intervention study (pilot study)