Why do I have to weigh myself so often?
What does kidney disease change about me?
Your kidneys are responsible for the production of urine in your body. With kidney disease, that process doesn't work so well anymore. This is why you will often have excess water in your body before you start dialysis. The fluid can no longer be excreted by the diseased kidney. In other words, the water tank in your body fills up or overfills. If the water retention is very strong, it even becomes visible and dents can be seen on the lower legs - your doctor may call this oedema. Although not everyone may feel bad right away with too much water in the body, it would lead to severe heart problems after a few months or years.
What does dialysis do to my fluid balance?
When dialysis therapy begins, it becomes possible to remove the excess water through treatment. The procedure to do this is called ultrafiltration. As water is being removed from your body through dialysis treatment, your body weight will go down. Signs of fluid overload such as oedema or shortness of breath should then also disappear. If you have a reduced or no daily urine output, it is very important that you only take in fluids in a controlled way -- regardless of the dialysis treatment.
Why do I have to weigh myself as a dialysis patient?
Weighing yourself regularly is a good way to know how much water you have in your body -- it's all about controlling how much you drink. As you can observe, your weight is usually at its lowest right after dialysis. This is because your body has been dehydrated right before -- during dialysis. Ideally, your weight should be as close as possible to the dry weight (= target weight) determinated by your doctor. Until the next dialysis, it will increase again mainly through fluid intake -- the less, the better.
Do I feel that I have too much water in my body?
Some dialysis patients get a good feel for the amount of water in their body over time. Others tend to have a hard time estimating it, even years later. No matter which group you belong to, it's important to weigh yourself regardless, so you understand as accurately as possible how much you've been drinking. I know -- your nephrologists and dialysis teams are often very persistent about this, but you have to understand: Above all, you are doing something good for yourself and avoiding side effects and subsequent problems.
Should I also weigh myself at home?
Regular weighing should become part of your routine. On dialysis days, you do it twice anyway. But also on dialysis-free days it is best to weigh yourself. Just turn it into a routine to get on the scale every time you brush your teeth! Especially on a "dialysis weekend" with two dialysis-free days in a row, it's super important to keep your weight in check. There are studies showing that most health problems due to fluid in dialysis patients occur on Monday and Tuesday, which is after the long weekend. There's no reason for this other than a longer interval between dialysis treatments. Therefore, it is even more important to drink less when the interval between dialysis treatments is longer. But who knows, maybe it's because Sunday is just a "healthier" day of the week?
How much can my weight fluctuate?
International guidelines recommend that your weight increase between two dialyses should not exceed 4% of your dry weight. So if your dry weight is at 70 kg, then your weight gain between two dialyses should be a maximum of 2.8 kg. The logbook of your Miku app is a simple and quick way to accurately document your weight changes.
So how much can I drink per day now?
European best practice guidelines recommend drinking a maximum of half a litre over your urine volume per day. If you still have a residual urine output, then the value can be adjusted upwards accordingly. For example, if you have 500 ml of residual urine, you can drink a total of 1 litre per day. If you have no more urine, you should only drink 500 ml per day. Please be careful, especially in the hot summer, and perhaps drink a little more. Everyone knows that the drinking requirements for people on dialysis are often a big challenge.
What do I get out of weighing myself so often and drinking less?
There is no doubt that dialysis causes fewer side effects (drop in blood pressure, feeling of exhaustion, muscle cramps) when weight fluctuations are small. Less water will be filtered out from your body -- dialysis is therefore "gentler". Studies also show that the quality of life and the risk of serious, in some cases life-threatening side effects are reduced if your weight increase between dialyses is at a regular rate. Regular weighing is a particularly important component of this.
What should I do if I weigh myself at home and weigh too much?
If you weigh yourself and your body weight is increased, you should not do one thing above all: eat less. There is no point in compensating for your increased water retention by reducing your food intake. On the contrary, you will not only upset your fluid balance, but possibly also your body's phosphorus, potassium and protein levels. So: distinguish between weight gain through fluids and normal food!
If you weigh significantly too much (depending on your body weight, more than 3-4 liters over your dry weight), you should contact your dialysis center. They will discuss with you what to do. If you cannot breath well, please call an ambulance.
Can I drink more if I sweat more?
Yes! Even though everyone is always talking about drinking, don't forget that it is only indirectly about drinking. Your body also lets fluid out through the skin when it sweats. So exercising more and taking regular saunas will allow you to drink more on those days. The bottom line is that it is about how much fluid is in your body, not necessarily how much you drink.
Try documenting your weight regularly in the Miku app. That's the first and most important step to getting your fluid fluctuations under control.
Weighing yourself is a method to approximate the water in your body
Weight fluctuations should be limited to a maximum of 4.5% of your dry weight, ideally as little as possible
It is best to make regular weighing at home part of your routine!
- Wong MM, McCullough KP, Bieber BA, Bommer J, Hecking M, Levin NW, McClellan WM, Pisoni RL, Saran R, Tentori F, Tomo T, Port FK, Robinson BM. Interdialytic Weight Gain: Trends, Predictors, and Associated Outcomes in the International Dialysis Outcomes and Practice Patterns Study (DOPPS). Am J Kidney Dis. 2017 Mar;69(3):367-379.
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