Fluid removal on Nocturnal

I seem to have a lot of difficulty coming off at my correct dry weight in the mornings.

During shorter treatments we allow 400ml for “washback” with saline plus whatever I want to drink. But overnight I don’t add anything for washback and still come off a couple of 100 mls under my dry weight.

Anyone have a similar problem. or any answers? Also what standing and sitting blood pressure are you in the mornings?

Sometimes for me but it mostly has to do with how much I have eaten or how much fat/calorie weight I have gained or lost…it fluctuates always…

blood pressure sitting averages 95/65 with pulse of 87 …standing averages about 110/78 with pulse of 89

Hi Beachy

I think this is a common situation. I almost always come off at least 200-300, sometimes 500ml lower than my calculated dry weight. Assuming no urination during the night or before weighing in the morning, on nocturnal, we’re on so long that we just naturally lose more water just from normal breathing and perspiration, the same as we do during the day. Also, I add 500 ml to my UF goal calculation for rinseback, but often I don’t end up actually needing that much to rinseback effectively. It’s not an exact science. As long as BP is Ok, an exact dry weight is really irrelevant in the context of nocturnal. It just has to be in the ballpark, so to speak.

Even when I was in centre though, for conventional hemo, it was a pretty rare day when I came off exactly as calculated.

My BP coming off is usually 120-135 systolic and 65-75 diastolic. Standing is about 130-150 systolic and 70-80 diastolic. But I do get a bit of a rebound hypertension after rinseback (always have). It settles down after, and by next treatment time, I’m often only 120/70 or less.

My DW does seem to move around as I either gain or lose real weight. So, if I see that I’m starting to be too low before treatment, I raise my DW by 200, or I reduce it by as much if my BP is getting a bit too high.

In the end, the main thing you judge your appropriate DW by is blood pressure. There is really no “correct” dry weight.

…just a combination of how it was explained to me and my own experience over the past year.


Thanks guys,
As usual you can both be relied on to answer promptly and set my mind at ease. To make things more confusing I think I must have put on weight (hopefully muscle, that’s what i am calling it anyway) from going to the gym :o

Can’t get any blood Pressure reading for a few hours after dialysis lately, no wonder I feel drained and sucked dry. Yes, I know this is dangerous, nurse told me to lower sodium from 140 to 138 a couple of weeks ago because my blood pressure was creeping up ! As you said, it is not an exact science.

You’re welcome Beach. Glad to help whenever I can. I don’t think you want to feel drained or dry when you’re on nocturnal. Contrary to every other kind of dialysis, it’s extremely easy to gain weight since we can eat virtually without restriction. OK, for you, I’ll call it muscle :slight_smile:

As a result, we really have to keep on top of things with respect to dry weight and blood pressure. I know that I’m not happy going on when my BP is lower than 120. This has happened often over the past year and I’ve had to raise my DW. It’s really not like conventional dialysis where you have to suck out as much fluid as you can without fainting. There’s just no need for that on nocturnal because BP is normal without drying ourselves out, and we don’t have to worry about leaving every ml of room we can so we can drink until the next dialysis.

I started gaining real weight almost immediately after I went on nocturnal - returning more to my normal, pre-sickness weight. At first I was a little wary about increasing my dry weight as I was told to do by my nurse. On conventional, I had been at a DW of 56.5 kg for over 2 years without change, but now I was raising that by 200ml at a time every few days with little effect on my BP. I ended up at 62.5 kg, which seemed like it was very heavy for me. But it wasn’t fluid gain, it was real body mass I had gained gradually over a few of months, so, it was Ok. I don’t want to tell anyone what to do medically, but I can guarantee that increasing DW 200ml at a time isn’t going to be a problem. At one point, my neph even said to increase it by a whole kilo because my BP was too low. That solved the problem.


We were told to allow 300mils for saline. So yeah, not an exact science!!!
THe same happens to me too - 200-300 lower than calc. usually…but sometimes 100 higher. Who knows!? I put down the extra loss to time/breathing/slight perspiration perhaps? I always have a (roughly) 200mils cuppa once I’m on & occasionally a 2nd before I settle down. I usually add 200mils to account for them (whether I have 1 or 2), but it doesn’t seem to make any difference.

Beachy, My dad doesn’t come off the same either. It is normal for him to come off under what I programmed to take off as fluid. Beachy, I wonder if your just one of those persons who’s blood pressure normally runs lower. You shouldn’t feel drained coming off but I know my dad’s blood pressure going on and coming off can be anywhere from 110/58 to 90/56 once in a while he’ll have spell when its up in the 120’s but rarely. I agree you should probably up your dry weight. I don’t know about the rest of the crew but I don’t see immediate results when I change the dry weight.

How’s it going Marty? I still reckon you deserve a big, fat medal or at least a big hug!
Thanks for thinking of me. Yep, I had to increase my dry weight by a kilo! Yikes! 65 k’s and going up! Still can’t get my standing weight after dx but sitting was 118/76 so I figure I’m not dead(; Feel much better when I come off and can manage my morning walks again. Beach is stunning at the moment, autumn, lovely colors and surf is “flat as a tack”. When are you coming over for a holiday? 8)

Having a few set backs but nothing major at this time. Dad has to have the fistula looked at as the arterial flow wasn’t good. That’s a couple of months off because we only have 1 vascular surgeon in our area. But the cath is still working fine. I would love to make a trip back to Australia someday. You have a beauty there that we just can’t see at home. I have a vivid memory of getting up in the morning and the weather was beautiful, I’d go for a walk and couldn’t believe all the colorful, beautiful birds I saw. At home to see a bird that isn’t brown or black is unusual and not a daily event. I couldn’t believe the trees were loaded with colorful birds. Not to mention the flowers.

This picture taken recently from our deck is for you, Marty :smiley:

Beachy, Sure does make me long to come back.

Hey, we’ve got some pretty spectacular tulip beds right now up here (literally millions of tulips). It’s the annual Ottawa Tulip Festival. If I had a digital camera, I would post some pics. Not exactly tropical, but pretty impressive. The tulips are in fine shape this year. You can check out the photo gallery at http://www.tulipfestival.ca/


Rinseback is commonly misunderstood and incorrectly calculated. There are two methods for starting dialysis – “give prime” and “dump prime.” Home patients are almost always taught the “give prime” method to avoid accidently dumping blood which is an inherent risk of “dump prime.”

The mistake that is commonly made is to assume that the prime that is given when going on must be added to the prime involved in going off which leads to a number that is too high by a factor of two. A litle thought will suggest why this is true. The correct number is the amount that the saline bag goes down from the start of dialysis to the finish. That may also be calculated by adding the capacity of the dialyser and the tubing set – both are on the packing information sheet or package. This is typically about 250 ml. To be precise you need to add the saline given as flushes which is 40 ml if you are using four 10 ml syringes. This adds up to about 290 ml (in my case about 270 ml with Fresenius F-160 dialysers).

Weight reduction during nocturnal dialysis is typically about 100 ml more than this number which is the result of breath moisure and perspiration losses. It might be more or less for some patients. Thus, setting UF goal to about 100 ml (or whatever is right for you) less than the calculated amount will result in hitting your goal almost exactly every time (this is true with a Fresenius 2008K machine; I’ve found the NxStage machine to be less exact).

I’ve found that about 8 out of 10 dialysis nurses in centers or hospitals share this misunderstanding, but the light dawns on them when it is explained.


I think Gus and Pierre are correct , it has more to do with how much you have eaten before you go on Nocturnal, the amount you urinate and also solid removal when you come off in the morning.

As we all seem to use different dialysers and probably bloodlines this has been worked out exactlty by our very reliable home training nurses that do know what they are talking about! Mine has been doing it for a very long time. To generalise by saying it is typically 250ml is misleading. As Beachy said Nocturnal is a different ball game than shorter runs which can usually be more precise with dry weight.

It’s always just a ballpark kind of thing at best. For one thing, the exact amount of saline you end up using to rinse your blood back is going to vary - we just decide visually when the bloodline is clear enough. When talking weight, we’re not really interested in a couple of 100 ml. 500 ml starts to make a difference in blood pressure.

We are taught that if we over or under acheive our UF that the machine needs to be bleached to get rid of the fat residue on the membrane. If bleaching doesnt help, you need to contact your unit. That is what we do with the Gambro machines anyway. Have just had to swap my machine for another, as my UFs were all over the place.

Forgot to mention…if I have a biggish meal before nocturnal, I weigh myself before and after dinner, to make sure the weight of my dinner is factored in to my UF.