The Obsession with Dry Weight

[Ken Shelmerdine]

I am amazed how fundamentally flawed the assessment of dry weight is in kidney dialysis. It doesn't take a medical genious to work out that weight is not only determined by the amount of excess fluid you may be carrying but also by what you have eaten and the amounts you have eaten since the last dialysis session. Why is this not taken on board when it comes to excess fluid assessments?

I have seen the consequences of this at my clinic when on several occasions a patient's blood pressure drops so low they either become semi or completely unconcious and the UF removal has to be switched off. Then they wake up a few minutes later in agony with the most horrendous cramps and the staff dashing about with cups of water to re-hydrate the patient.

And yet the same inaccurate process goes on and on  as if there's nothing that can be done about it and we just have to put up with it.

Is there a way by which true excess fluid volume can be calculated by deducting any possible increase in body mass/weight  plus the weight of clothing you are wearing to arrive at an accurate fluid assessment. If there is why has this not been adopted?

I'm so glad that I don't need UF removal but why do I still feel pressured when I'm over my 'dry weight'? 

[peleroja]

Add in the fact that you are actively trying to lose weight, and you might get the opposite effect.  They want to take off less fluid, yet you know that you have been exercising like crazy and eating carefully, and most likely the weight drop is due to "real" weight, not less fluid.  Finally the doctor listened to me and dropped my dry weight completely. 

To help the dry weight process, I wore the exact same clothing every single time I went, so at least the clothing wasn't a factor. 

[YLGuy]

Ahhh! Dry weight!  I was originally 75K's.  I would come in at about 78 K's and they would pull 3-3.5 off of me.  Then for some reason they dropped it to 74 K's.  I sometimes would get the most horrific cramps.  So bad that I could only shuffle the next day.  My new center & neph changed it to 78 but I could feel it in my feet that I had too much fluid so I spoke up.  I am currently at 77 K and they usually pull 1.5 off and life seems to be good.  The fact is that this obviously changes.  I am the one who suggested 77K and my new neph seems to think I am in tune with my body enough for him to write the Rx based on my input.   

[monrein]

With self-care and home hemo I always chose my own settings and they were variable depending on various factors.

[willowtreewren]

I am the one who suggested 77K and my new neph seems to think I am in tune with my body enough for him to write the Rx based on my input.   

This is fortunate for you , Marc. Since we do dialysis at home, I simply ask my husband whether he wants any extra removed. He still urinates, so it is rare that we draw off any extra besides the rinseback. When he was in-center they were always looking at his imaginary dry weight. My husband is slim with no extra fat and when he eats a big meal, he carries that extra weight for a day. His weight varies day to day from 60.0 to 62.8. And it isn't fluid retention. 

[bette1]

I don't gain between treatments usually because I still urinate a lot.  I tell the nurses how much I want taken off.  Even then I may still cramp, so I have to be really careful.  Right now I have been losing weitht so it's been hard.

[RichardMEL]

Yep, it is a constant struggle to figure this out and it is such a guessing game.

Lately for example my BP has been a little higher than normal, so you instantly think "OK, maybe it's time to lower the dry weight" - took 300 grams off the dry weight and the session went bad - clearly too much fluid taken off, so go back to the original dry weight. BP still high, do BVM which suggests I am refilling OK so not too wet or too dry. OK that's good. Then I just had a weekend away and drank more than usual(hey, I wanted to enjoy my mini-break) and came in... 0.9kg over?!?!?! what the?? Have I lost weight? Doubtful - I had big meals! Did I urinate/sweat the fluid out? Don't think all of it went... so what's the deal? Who can tell? My BP was even higher?!?!!

Strange!

[jbeany]

I think you just have to take charge and set your dry weight for yourself.  I tell them what I weigh and how much of it I want off.  I've been losing weight as well, so I keep a close eye on the things that show fluid gain the most - my fingers especially.   My center is used to me being in charge by now, so no one argues about the UF goals I set.
When I rub my fingers together after a treatment, I should feel nothing but skin and bone.  Any poofiness means there too much weight on.  I rarely push more than an extra .3 at a time, though.  Most of the time, the machine takes off .1 or .2 more than the actual goal.  Whenever I leave lower, that becomes my new dry weight, so some weeks, I leave Friday down .5 or .6 from my dry weight on Monday, even without adding extra to the goals.

The last 3 months in a row, my doc has reset my dry weight during my clinic - and I've left that day lower than what he just lowered it to.  If I waited for the doc to approve a new dry weight before I adjusted it, I'd be fluid over-loaded all the time.

[RichardMEL]

Oh yeah I agree. I pretty much set my own dry weight and UF goals myself too. Like you the staff know that I've been there, done that and have half a brain(and take interest in my own treatment, labs and all that) so they just let me set up the machine with what UF goal I want, profile, temp and all that. I just make them write it down so they feel like they're doing something useful ! 

I like it that I have some say and control over MY treatment and conversely if I crash or have a problem due to a change *I* made well I've got nobody to blame than myself. At least I know it's MY decision and not that of some random other person. The staff though are really good with helping, like setting up to do a BVM to see how I am refilling and all that).

Have I mentioned that I like my unit?

[Wayne]

It is fun....I fight with my neph about dry weight every week.  I still produce urine and don't drink a whole lot of fluids and try to watch my intake.  Here lately it doesn't matter how close to my dry weight I am, they still pull too much off and my pulse will be through the roof.  We haven't found that happy medium yet.  I keep telling them it's not fluid I am coming in with, it is actually true weight bc my appetite is coming back and I am eating more.

[thegrammalady]

dry weight is only a guess the doctor makes. i've solved the problem by always wearing the same or similar clothing and tracking my weight from treatment to treatment. i know what i weighed when i left and subtract it from what i weigh when i arrive. i also know my body. if i've eaten half a loaf of garlic bread with my spaghetti, i know it's weight gain and not fluid gain. i never let the tech set the goal based on anything they think. i always tell them what to take off and ask them to stop the pull if i start to cramp, works for me.

[Rerun]

Dry Weight is a moving target.  Like nailing Jello to the wall.  It is your weight minus any extra fluid.  Ok.. that means you have to take into account:

Your clothes (I also wear the same outfit to dialysis)
What you have eaten
When the last time you had a BM
I don't pee at all so I don't figure that in
If it is hot out and you sweat

The best thing is to have a scale at home and weigh yourself when you leave dialysis and come home and weigh again so you know if it is calibrated correctly.  Then you can watch what you gain.

Doesn't always work, but it is a good tool.

[RichardMEL]

yep - what ReRun and the TGL said..

I wear similar weight clothes every time, and weigh myself several times a day at home. I know what the difference between my scale and the hospital scale is, so I use that to work out where I am - and I keep track of what I drink as another way of knowing how much fluid I've put on. I almost always keep it to 2kg change or less between sessions, which is the recommended level.

[rocker]

Well, we're at home now, so his dry weight is anything we say it is.  If he's awake I tell him when we've reached goal, and if he doesn't feel dry I walk it down by 100ml at a time, checking his BP each time.  (He thinks I'm being overly cautious, but I saw 74/42 with a pulse of 42 once during training, and I never want to see that again.)

One question I have - is crashing/cramping the ONLY problem with pulling too much?  One day he forgot to take his morning BP meds (though I didn't know this), and he ran high all during treatment.  I kept walking him down, and his BP never did get down to normal.  So really, if his BP is ok and he's not in any discomfort, am I ok in taking off more fluid?  He always wants more fluid off, and I just wonder if there's some other problem I should be looking for, particularly if his pressure is high due to insufficient meds.

 - rocker

[willieandwinnie]

rocker, you have to remember that sometimes if you take off too much fluid that the blood pressure will also go high. Len would weigh himself 100 times a day (probably not quite that many) and we did home hemo and I would challenge him occasionally to see if we had his dry weigh right. There was many times when I had to give him back fluids because he would crash. Hope you get things figured out soon. 

[jbeany]

Well, we're at home now, so his dry weight is anything we say it is.  If he's awake I tell him when we've reached goal, and if he doesn't feel dry I walk it down by 100ml at a time, checking his BP each time.  (He thinks I'm being overly cautious, but I saw 74/42 with a pulse of 42 once during training, and I never want to see that again.)

One question I have - is crashing/cramping the ONLY problem with pulling too much?  One day he forgot to take his morning BP meds (though I didn't know this), and he ran high all during treatment.  I kept walking him down, and his BP never did get down to normal.  So really, if his BP is ok and he's not in any discomfort, am I ok in taking off more fluid?  He always wants more fluid off, and I just wonder if there's some other problem I should be looking for, particularly if his pressure is high due to insufficient meds.

 - rocker

As long as his bp is high, yes, you can keep trying to push - but watch how he feels after the treatment is done.  Getting too dry can lead to lots of weakness, headaches and nausea for the rest of the day, regardless of the bp.  Does he have a spot where his fluid over-load shows the most?  Mine all seems to collect in my fingers, so I gauge my dry weight by that as much as I use the scale.

I also don't like to push more than .3 or .4 at a time.  It's just too easy to get stripped dry and then have no energy for the rest of the day.

[sico]

When i started HD the staff weren't taking anything off me at all and at the end of treatment i'd be busting to go to the loo. My bp would be high too . Then my neph dropped my dry weight 3 or 4 kg's in the one session and that gave me lower bp. I couldn't notice the extra fluid, no swollen ankles. At the start i really had no clue what was going on, didn't want to lose weight. Later on i would negotiate my weight with the staff. I could really tell if they'd taken a tad too much off as i'd feel really weak after HD.

[Meinuk]

(I totally got off topic when I started writing this.  I have been thinking about what Kickstart has been going through lately)

But dry weight is just a guideline at best.  Techs and nurses don't always pay attention to the patient, they simply follow the doctors orders.  Sad but true.  That is why we need to educate ourselves - and why IHD is so important to me.  Proper Health Care should not be a battle, but it is and we are all in it together.

I put my foot down from day one about my dry weight, and we used my BP as an indicator.  (as I did not have any BP issues and was not on any BP meds). 

Fluid & Toxins what a pain.  Unfortunately, our bodies are not set up for fluid removal in short intervals (yes, compared to 7 - 8 hour nocturnal, 3 hours is considered short).  Which is why 3x a week dialysis is at the bottom of the dialysis therapy list.

Dr. Agar in Australia has written some amazing stuff about why we can't get much fluid off in one dialysis run, and why we feel so terrible.

Here is a link to what he wrote on Home Dialysis Central

http://www.homedialysis.org/resources/tom/200711/

Bill Peckham has also written a lot explaining why longer, slower dialysis is better for moving fluid & toxins from the different parts of your body to your blood stream, and then out of your body for good (or until your next drink).

In short:

We store fluid in three parts of our bodies:  1)our cells, 2)our extracellular spaces and 3)our blood.
dialysis only removes the fluid from our blood.  There isn't enough time in 3 hours to move the fluid from the cells to the extracellular space and finally to the blood (the access point for dialysis).  This is why we cramp, and our blood pressure drops.

As people have suggested in other threads, adding extra days on the machine helps.  Don't try to take everything off at once, that will just make you crash by removing the fluid from your blood stream, and leaving you dehydrated, cramping, and your body trying to adjust - your cells and extracellular spaces will still be fluid overloaded.

Bill has written a lot about Dr. Agar's presentations:

http://www.billpeckham.com/from_the_sharp_end_of_the/2007/12/dr-agar-on-flui.html  (worth a read and there is a graph!)

Dr. Agar on fluid and solute removal

(hat tip Rich on HDC)

Rich points to two articles (part 1; part 2) by Dr. Agar on Home Dialysis Central. I really enjoyed the articles in no small part because I agree so completely. It's always a joy to read something well written and authoritative that confirms your own belief.

The critical concept is in Part 1, he in fact writes "Okay...focus here...it is crucial that you understand this next bit!

"When HD removes a waste or fluid from your blood, it only reduces your blood level of that substance. When your blood level drops, a gradient (difference) forms between the blood and interstitium. This occurs because now the interstitium has more of the substance than your blood does.

Your body wants fluid, salts, and wastes to be in balance between your three fluid compartments. Keeping this balance, called homeostasis, is the main job of the kidneys. To restore balance, dissolved substances (solutes) always move from a compartment with higher level to one with a lower level.

So, as the blood level of a solute falls, this forms a gradient between your blood and interstitium. The solute will then move out of the interstitium and back into your blood. And this creates a second gradient between the interstitium and your cells. In this way, removing "X" from your blood will remove "X" from your interstitium, which, in turn, will remove "X" from your cells. Each of these steps takes time."

This is the crucial concept. The way I imagine the situation is each molecule is a color - a pixel of color. Red, green and blue, red are the small easy to remove molecules potassium and phosphorus, green are the harder to remove molecules phosphorus and beta2, and blue are water and salts.

At the start of dialysis all three compartments are white (the D65 point) because the colors are balanced between the compartments. If the red - small molecules come out fastest then there will be a color shift away from red to teal. I think you would see waves of color rippling through the body. As the blood reentered the blood stream from the venous needle it would be most teal and as it mixed in the blood compartment the blood stream would take on a blue/green tinge.

[THE GRAPH IS HERE] This tinge would spread to the interstitum and finally to the cells. This kaleidescope would continue and based on Dr. Agar's explanation you'd see a shift towards purple in the blood compartment because the green molecules would be removed faster than they could be replaced from the interstitium.

A high ultrafiltration rate would turn the blood compartment yellow as water is removed faster than it can be replaced. Another element that Dr. Agar did not discuss is that the blood does not circulate around the body evenly. My understanding is that at rest the blood tends to stay in one quarter of the body or another. I think if we could see the body as a whole we would see more rapid color shifts in the quarter of the body with the an extremity access (not sure of the impact of a catheter).

Dr. Agar's article was in two parts - I think my response will be in three.

 

[tyefly]

     Thx    Meinuk.....    for the information.....  I really want to go that route of slow and long.......  I hope to stay healthier  and Live longer.......
                    I have learned so much from all of you ......   I still have so much more to learn.......   


                      Kathy

[Ken Shelmerdine]

 

My husband is slim with no extra fat and when he eats a big meal, he carries that extra weight for a day. His weight varies day to day from 60.0 to 62.8. And it isn't fluid retention. 

Absolutely! and if you were dialysing at a centre it would tke you ages to convince them of that because the first assumption they make is that the extra is all fluid.

Meinuk the articles from those links are so well explained. Its not often you see the results from a study set out in terms and language we can all understand.

Judging by the posts to this thread it seems many of us are in control and make their own decisions about what is suitable fluid removal set against dry weight. I've also learnt from this that excess fluid seems to reflect in high BP.

 When I get to dialysis my BP is normally about 130/80 and after dialysis it drops to about 105/60 so maybe I'm right about insisting on no fluid removal. They seem to accept it now at my clinic but it took quite a while to convince them.

I feel sorry for some of the more elderly patients at my clinic who for one reason or another have no proper understanding of their treatment and are therefore completely at the mercy of generic treatment management having neither the confidence nor the knowledge to to direct  any aspects of their dialysis.







EDITED:Fixed quote tag error-kitkatz,Moderator

[Zach]

 My husband is slim with no extra fat and when he eats a big meal, he carries that extra weight for a day. His weight varies day to day from 60.0 to 62.8. And it isn't fluid retention. 

Absolutely! and if you were dialysing at a centre it would tke you ages to convince them of that because the first assumption they make is that the extra is all fluid.

Don't you folks ever have a bowel movement?

 

[Ken Shelmerdine]

Just been for one actually!

[willowtreewren]

 

What is BM?

Bad mouth?
Big monster.?

 

In seriousness, it depends on what time of day we dialyze and when he goes number 2! 

[RichardMEL]

Sometimes during treatment my BP will go sky high and I'll sweat and become very clammy and uncomfortable. It's just as yuck as a low BP crash - so yes, both can happen (I sometimes wonder what the difference is). stopping the UF and giving some saline usually fixes me up in a few minutes.. luckily that experience is pretty rare for me because it is NOT fun at all! (but better than cramping)

[bountyhunter_ga]

Hello all, This seem to be a problem for most of us. At my center they have started asking me about my dry weight and not just plugging me in like some kind of battery charger.

When you get single treatment from the same person most of the time it works better. Make them talk to you , I carry a gun and a badge, people look at you a little different and sometimes treat you a little better.

This is not necessary right its just the way it is. This takes me back to control, be in control of your dialysis its your body.

Keep it simple if you start gigging leg cramps have them them cut back or quit the session with you.