1. A dialysis apparatus for treating tissue fluid, such as blood or plasma, comprising: a dialyzer (1) containing a chamber in which a dialysis membrane (3) is placed, dividing the chamber into a section for passing said tissue fluid, called a tissue section liquid (12), and to the section for passing the dialysate, called the section for dialysate (14)； said section for tissue fluid (12), respectively, the said section of dialysate (14) containing the inlet (201) of the tissue fluid, respectively, the inlet of the dialysate (401 ), and tissue fluid outlet (202), respectively dialysate outlet (402)； dialysate supply system (5) containing a dialysate supply line (52) connected to the inlet (401) of the dialysate section (14)； dialysate evacuation system (6 ) containing a dialysate evacuation line (62) connected to the output (402) of the dialysate section (14)； a control unit (10), such as a programmable machine, which contains: ultrafiltration (UF) controls that allow at least , through part of the membrane (3), tissue fluid water from the tissue fluid section (12) to sections for dialysate (14), retro-filtration (RF) control means allowing the dialysate to pass through at least a portion of the membrane (3) from the dialysate section (14) to the tissue fluid section (12), characterized in that the line ( 52) the dialysate supply comprises a narrowing of the passage (520), said apparatus comprising means for measuring a pressure difference (523, 524) at the boundaries of said narrowing of the passage (520), said dialysate supply system (5) also comprising: at least one elastic a container (50) called a ventricular container1. Аппарат для диализа, позволяющий обрабатывать тканевую жидкость, такую как кровь или плазма, содержащий:диализатор (1), содержащий камеру, в которой размещается диализная мембрана (3), разделяющая камеру на секцию для прохождения упомянутой тканевой жидкости, называемую секцией для тканевой жидкости (12), и на секцию для прохождения диализата,
