the fluid processing cartridge 18 to a hemofilter 34 mounted in brackets to the side of the chassis panel 26 as shown in phantom lines in fig2 to 5 back to the cartridge 18 and then back to the person alternatively the hemofilter 34 can form an integrated part of the cartridge 18 the hemofilter 34 is connected via the cartridge 18 to the person 39 s blood supply through the vascular access devices 14 the machine 16 includes a blood handling unit 36 mounted on the chassis panel 26 the blood handling unit 36 includes a peristaltic blood pump 92 and various clamping and sensing devices described later the blood handling unit 36 circulates the person 39 s blood in a controlled fashion through the hemofilter 34 and back to the person the hemofilter 34 removes waste fluid containing urea and other toxins the machine 16 also includes a fluid management unit 38 mounted on the chassis panel 26 the fluid management unit 38 includes a peristaltic waste and replacement fluid pump 152 and various clamping and sensing devices described later the fluid management unit 38 replaces the waste fluid with a sterile replacement fluid for return with the treated blood to the person 39 s blood supply the replacement fluid also acts to maintain the person 39 s electrolytic balance and acid base balance the fluid management unit 38 includes a fluid balancing element 40 mounted on the chassis panel 26 the fluid balancing.