Help me please: sodium???

[misslynette]

When Mike got out of the hospital in April, I had to throw a flat out hissy to get any information about diet. It was so frustrating, because the recommended diet is a drastic change from our usual heavy on fruits-and-veggies, dairy, etc.

I get the potassium thing, and I understand the complications from too much phosphorus.

Which leaves sodium. Finally, after two months of asking, we have a little clarification on how sodium affects dialysis people. I found it confusing for a lot of reasons.

Salt makes you thirsty, leads to higher water consumption;
But if you strictly limit the water, how does salt hurt?;
Except that it would affect the fluid balance between circulatory system and tissues? drawing fluid from tissues into veins or vice versa?;
Which would hurt the body how? Or would it? Is the sodium restriction just another form of torture?

Mike's been steadily increasing his sodium intake over the last couple of weeks. That's the worst thing for him, lack of salt. So in clinic Saturday, he asked the nurse again, and got way more info than ever before.

Sodium levels enlarge/constrict the heart due to ... ? what? did she tell us? But the constant enlargement and constriction eventually reduces the elasticity of the heart and that's bad. CHF, I guess.

But how could the heart enlarge/constrict if water intake is strictly controlled? High sodium concentration in the circulatory system would cause fluid to move from the tissues into the circulatory system, which would enlarge the heart?

Is this right? I have never felt more like I'm running through fog than I have with this whole kidney thing. And I don't trust medical people, so just because they say it doesn't make me believe them.

Thoughts on this? I realize this is probably elementary dialysis stuff and I did search the index, just didn't find exactly what I needed to know. So thanks in advance for any clarification y'all might be able to provide here.

[Bill Peckham]

It sounds to me like you understand - the main problem with sodium intake is that it causes thirst. If Mike isn't gaining >2 kilos then that shouldn't be an issue.


The other sodium impact is on transfer rate. The rate at which fluid moves between the body's fluid compartments - either from inside the cells to the space between the cells, or from between the cells to the blood stream. The transfer rate is like a speed limit on how fast you can draw off fluid during dialysis. Generally the transfer rate is between .3 and .7 liters/hour - a higher sodium intake is said to lower the transfer rate.


Does Mike have cramping or low blood pressure during dialysis? Those would be symptoms of too high a UFR and exceeding the transfer rate.


I'm a big advocate of low salt diets for people using dialysis - but in the absence of symptoms: Thirst/high UFR, high BP (pre D), dropping BP during D - I wouldn't say you need to increase your sodium restriction. How much sodium is he eating? Are we talking Denny's Ham over Miami salty or are we talking using the salt shaker salty?

[Ang]

sodium=thirst

excessive thirst/fluid=heart damage from constant removal from excessive fluid removal
losing elasticity is 100% correct.

[RichardMEL]

I was also under the impression that too much sodium can add to the body retaining fluid and pushing up blood pressure - both of which are bad for any residual kidney function.

The main concern though is the thirst I agree. Many people do not have good willpower to limit themselves strictly and thus the idea is to limit the desire as much as possible.

What I did in terms of sodium was that I *never* added salt to anything I cooked or when I was eating out, but if some chips or something came with salt I didn't make a big deal about it (and enjoyed it ). I was usually pretty strict with myself on my fluid intake, which definitely helped so I was most focused on things like Potassium and Phos intake since I mostly had the fluids covered.

[misslynette]

Thanks for the input people, I think I've got a better grasp on it.

With regard to fluid retention, I can't understand how you'd retain excess fluid ~ as I do when I go overboard on salt ~ when fluids are so limited?

[RichardMEL]

I think it has something to do with fluids being "trapped" in the cells of the body rather than the bloodstream (dialysis removes fluids from the bloodstream, but if it's trapped elsewhere and not transferring to the bloodstream then that's a problem) and I think salt aids in that. So even if your intake is limited, fluids may build up over time because they're not being removed.

Of course I may be way off base with this one - so expect a correction from one of the folks on here who knows more!

[Riki]

no, Richard, I think you're right. 

If you have no other way to remove the fluid besides dialysis, then salt will aid in the retention of any fluid you take in, and then that fluid has to go somewhere. Most people see it in their hands, face, or feet.  I see it in my upper legs, and it can make walking extremely difficult if I have too much fluid on.  It can also go around your heart and lungs, causing strain to your heart, and making it hard to breathe.  Too much fluid retained can also cause your blood pressure to rise, and that can also cause damage to the heart.

As dialysis patients, we really have to look after our hearts, as they are now more vulnerable with our kidneys in failure.  The kidneys are what normally removes the fluid that can build up around the heart, and with them gone, all we have left is dialysis, and it's no where near as good as our kidneys were when they were healthy, and if the heart goes, we're pretty much toast.