On some of the newer machines there is a crit line which can establish when the blood is replenished with fluid and can have more pulled off, but our Techs don't know how to use it so we don't.
I see people come in with 7 or 8 kilos on over a weekend and then they wonder why they can't get the fluid off. Dialysis can only do so much in 3 or 4 hours. It takes time for the fluid to shift from tissue to blood in order to be pulled off. People have got to restrict their fluid so that the machine has a chance to take off what is needed.
Some people just rely on the staff to know what to do and that is a huge mistake. You have got to know how you feel and learn to play with your own dry weight. There is this one lady that has a BP of like 85/60 and wonders why she feels sick all the time.... she won't stop taking her BP medication because her "doctor" didn't tell her to. Come on!
At Fresenius, we had something called a "Crit Line".
It was, to say the least, a three-times-a-week fight. Eventually (and it took about six months of arguing, and my being extremely aggressive), the facility administrator put in Marvin's chart that he could set his dry weight before every treatment. This worked well. Marvin knew how his body felt on the inside; he knew the "signs" of too much fluid as opposed to actual weight gain. But, no one else at Marvin's clinic ever questioned their dry weight. They crashed, and crashed, and crashed again. It used to make me so mad.
Ask them to do a BVM to work out how much fluid you are carrying. I kept having extreme low BP"s at the end (85/65) so a BVM determined that I was very dry. The staff put my dry weight up a fair bit (almost 5 Kg over time) and the problem of low BP's disappeared.
I've just viewed the link which Zach posted. It is a study of the use of a Body Composition Monitoride provide a more accurate dry weight assessment. I can't beleive why they are not widely used in dialysis wards. Hell you can buy one for your bathroom for about fifty quid! Murf you mentioned a BVM which I take means Body Volume Monitor. Are these the same thing as a BCM?