Potassium & dialysis: the basics
Potassium -- the engine for your muscles
Potassium is responsible for many different tasks in your body. Potassium is an important basic building block of all your body cells and regulates, for example, the fluid content in a cell. Potassium is also responsible for the transmission of impulses in your nerves. In other words, it is a key component for the communication inside your body. It is also involved in the control of your muscles. Almost 99% of potassium is found in the body's cells, only 1% in the blood.
The kidneys are largely responsible for regulating your potassium levels in the body. Potassium enters your body through your diet, because potassium is in all foods - some a lot, some only little.
Hyperkalemia & Hypokalemia
Both can occur with dialysis: If your blood potassium levels are high, your doctors call it hyperkalemia -- you have too much potassium in your body. If your potassium levels are high, it's important to make sure you're taking in less potassium through your diet.
However, the opposite also happens occasionally, which is that people with kidney disease have hypokalemia. Diarrhea, vomiting or diuretic medication can also lead to too little potassium in a body.
However, for most people with kidney failure, too much potassium rather than too little is the key challenge needing to be mastered.
Potassium fluctuates relatively quickly
While potassium can be reduced during dialysis, it unfortunately rises again very quickly during dialysis-free intervals. Even a moderate serving of potassium-rich fruits or vegetables may cause your potassium levels to skyrocket.
If you are not on hemodialysis but peritoneal dialysis (PD), you are less likely to have problems with potassium fluctuations. Since PD involves continuous dialysis operations, your body and therapy can keep the potassium better under control.
What is the approximate target value for potassium?
In dialysis patients, the approximate normal range for potassium in blood plasma is between 3.5 and 5.0 mmoL per liter. The upper normal range may be slightly different from lab to lab. It is best to ask what it is at your center. A potassium level above 5.0 mmoL per liter (or above the upper normal range) is called hyperkalemia. At a potassium level above 5.9 mmoL per liter, physicians speak of a moderate to severe hyperkalemia that should be treated quickly. Values above 6.5 mmol are always severe and very critical hyperkalemia.
How do I feel if something is wrong with my potassium?
Mild excess potassium can be treacherous because it doesn't necessarily cause symptoms. Sometimes it can bring on signs such as a tickling or numb skin, diarrhea, or muscle weakness. In more serious cases, muscular paralysis are sometimes reported. If the potassium skyrockets, it can cause very dangerous heart palpitations and arrhythmias.
If, on the other hand, your potassium level is too low, it can sometimes sometimes manifest as muscle weakness, cramps, or muscle paralysis. Low potassium, like high potassium, can also cause heart palpitations and arrhythmias.
Reading this paragraph, you will surely realize why potassium is treacherous: Because you don't necessarily feel too much when your potassium level is too high or too low, you should pay special attention that your value is in the target range - even if you feel good.
So how can I reduce potassium?
As mentioned earlier, dialysis can reduce your blood potassium. Your doctor may still be able to prescribe some medication called potassium binders. Most importantly, however, it is vital that you take care of controlling your potassium through your food intake. This can happen in two different ways:
Your food choices: potassium can be found in all foods. As a dialysis patient, it is important to be aware of the potassium level in foods. Especially many plant-based foods can contain a relatively high amount of potassium.
The preparation of your meals: Potassium is water soluble. On the one hand, this is good, but on the other hand, it turns known "healthy" cooking methods a bit upside down. For example, you can cook things longer to reduce their potassium content. Since hot water removes potassium, it's better to throw away the cooking water after cooking and not use it again, as it then contains all the potassium that left the ingredients during the cooking process. In the Miku app you can also find many other tips & tricks on how to cook delicious things in a potassium-conscious way.
How much daily potassium can I consume?
For people with health kidneys, a complete, mixed diet including beverages contains about 2,100 -- 4,800 mg of potassium per day. For people on dialysis treatment, a maximum of 1,500 mg is often set as daily guideline, depending on the actual blood potassium level. For an exact adjustment of your daily recommended intake, you should definitely refer to your nephrologist or a nutritionist, who is experienced with dialysis.
Since it's the total amount of potassium that matters, you may already have realized that it's not necessarily a matter of cutting certain foods out of your diet completely. It is more important that the total amount of potassium is within a target range throughout your day. Logically, there are also one or two potassium bombs that you should try to stay away from completely.
You can set your daily recommended intake in the settings of your Miku app. By doing so, you can better interpret the foods in the food search. In the Miku app you will also find numerous other tips on how you can better manage your potassium.
Potassium is responsible for your body's nerve- and muscle functions, and as it is found in almost all foods, it is primarily absorbed through the diet
People with kidney disease can have both too much potassium (=hyperkalemia) and too little potassium (hypokalemia) in their body
You should only cook and eat low-potassium foods if your potassium levels are actually too high, because too little potassium in your diet can be just as harmful
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