When 59 year old Sara Jenkins, a middle school teacher, on her return from a field trip to Disneyland with her students, felt numbness in her hands and feet, and a tingling sensation on her skin, along with fatigue and vague feelings of nausea, she dismissed them as just tiredness from the trip. However, during the following week, she felt the same symptoms recurring, she decided to pay a visit to Dr. Arlene Hallowell, her friend and her doctor.
She was surprised when Dr. Arlene said that she would have to take a blood sample for a blood test, along with taking an ECG.
"But Arlene, I just feel a little tired, maybe all I need is a pick-me-up tonic," she said, as she climbed up on the examination table for the ECG.
"Hmm... perhaps," said Dr. Arlene, as she fixed the ECG machine, "but I just want to double-check."
"Double check for what? I really don't feel all that bad, it's just that these symptoms have been persisting that I came to you... Oh, you don't think it's a heart problem I have, do you?"
Dr. Arlene smiled reassuringly at her friend, and said, "Let's just wait for the blood report, shall we?"
When the blood report came three days later, Dr. Arlene called her friend over at her home in the evening, and told her that she had a condition known as Hyperkalemia, or high potassium levels in her blood.
"High potassium levels in my blood?" Sara said, puzzled, "But how can that be? I don't eat potassium."
"Actually, you do... We all do, in fact. Many of the foods we consume have potassium in them."
"Oh? I didn't know that... So why do I have high potassium levels in my blood, while you don't, then?"
"Look, let's settle down with a cup of coffee... I've made some already... And let me explain it all to you."
And as they sipped their coffee, Dr. Arlene explained what high potassium levels were all about, while Sara listened with rapt attention. She began by explaining what potassium was and its function in the body.
"Potassium is an essential mineral required by the body for controlling muscle and nerve function. One of the most important muscles in the body, the heart, beats normally due to potassium. Plus, the body requires potassium in order to maintain its pH level along with electrolyte and fluid balance. We get potassium from the foods we consume. It can be dangerous if the potassium levels in the blood get too low or too high.
The normal level of potassium in the blood is between 3.5 and 5.0 mM. When the potassium level in the blood goes beyond 5.0 mM, the condition is referred to as hyperkalemia, or the person is said to have elevated potassium levels.
In a healthy person, most of the potassium exists in organs and various cells, with the concentration being up to 150 mM. This is in contrast to the amount of potassium found in the blood, which is much lower, containing only 0.4 percent of the body's potassium. When there is overall excessive potassium in the body or if the potassium shifts from inside the cells to the outer regions, it can lead to hyperkalemia. For instance, if the muscles suddenly release potassium into the fluids surrounding them, it can cause hyperkalemia.
Normally, the body eliminates the excessive potassium in its system that it gets from the diet by implementing three kinds of regulatory processes. First, the organs and cells take up the potassium in the blood in order to prevent hyperkalemia. Next, the kidneys excrete the excessive potassium into the urine. Vomiting is the third mechanism which prevents high potassium levels in the blood. Consuming a large dosage of potassium chloride, for instance, stimulates the vomiting reflex, which gets rid of most of the potassium, before it has a chance to be absorbed."
At this point, Sara had to interject. "OK, but why do I have high potassium levels, and not you?"
"Yes, I was just about to tell you that..."
"High potassium levels can occur due to a variety of reasons, such as consuming too much potassium salt in the diet; the inability of the kidneys to excrete potassium normally into the urine; potassium leaking from the tissues and cells into the blood; or due to acidosis. Although, about three-quarters of all the cases of hyperkalemia is because of renal, or kidney, disease.
The glomerular filtration rate, or the rate at which the blood is continuously cleansed by the kidneys, is how the function of the kidneys is measured. 100 ml per minute is the normal glomerular rate of filtration. However, if the glomerular rate of filtration is reduced to just 5 ml per minute or less, because of the kidneys getting damaged, it can lead to hyperkalemia, especially if foods that are high in potassium are eaten.
In fact, many elderly people usually have an increase potassium levels in their blood, because many of their regulatory functions don't work as well as in younger people. For instance, elderly people who take certain medications for high blood pressure, like Dyazide and Aldactone, should be monitored for the possibility of getting hyperkalemia because these drugs cause the kidneys to retain potassium.
High potassium levels in the blood can also be caused by Addison's disease, which is a condition that affects the adrenal glands. The adrenal glands secrete aldosterone, which is a hormone that helps the kidneys to excrete potassium into the urine.
Although not as common, but acidosis, or acidic blood plasma, can also lead to hyperkalemia. Acidosis can occur due to certain diseases, and it results in the hydrogen ions increasing in the blood. When this condition occurs, the body tries to get rid of the excessive hydrogen ions in the blood by absorbing it in the muscle cells, which leads to potassium being released into the blood instead. This, in turn, results in high potassium levels in the blood.
Injury to muscle tissue can also cause hyperkalemia. This is because, normally the muscle contains most of the potassium in the body, hence if the cells of the muscles are crushed due to some sort of severe trauma, the potassium in the muscle is released immediately into the blood. Similarly, severe infections or burns may also lead to hyperkalemia."
"So, which do I have?" Sara wanted to know, "Obviously I don't have any muscular injury, infection or burns, and neither do I take high blood pressure medications... So that leaves a malfunction in my kidneys, my adrenal glands, or acidosis."
"Yes, we will have to conduct further tests to determine exactly what's causing your high potassium levels," said Dr. Arlene.
But Sara wanted to know even more. "So, how dangerous is this condition? I mean, what's the worst case scenario?"
"Well, you have all the symptoms of mild hyperkalemia... the ones you complained about... like tingling in your skin, numbness in your limbs, fatigue and weakness... Also, the blood test I took confirmed that you have it in its mild form, because it detected that you had about 5.0 mM of potassium in your blood."
"Does that mean I don't have to worry?" Sara asked, hopefully.
"Well, not exactly," replied Dr. Arlene, "You see, if the potassium levels should rise up to 8.0 mM, then it can lead to your heartbeat increasing to dangerously high levels, which is called fibrillation. Sometimes that can even result in cardiac arrest, or your heart stopping to beat completely."
"So what can I do to prevent that from happening?" Sara queried, fearfully.
"Well, to begin with, cut down on fruits like bananas, oranges, kiwi, cantaloupe, papaya, dried fruits, honeydew, and prune juice... And vegetables like pumpkin, dried peas and beans, artichoke, potatoes, sweet potatoes, tomatoes, spinach, and winter squash, also ice-cream, yogurt, milk, chocolate, molasses, nuts and seeds, and salt substitutes, for these are all high potassium foods."
"But what do I eat then?" exclaimed Sara in dismay.
"Well, actually there are lots of foods that are low in potassium, so you really don't have to worry too much. For example, in fruits you can eat apples, grapes, berries, peaches, pineapple, watermelon, lemon, and plums... As for vegetables, carrots, cauliflower, cabbage, eggplant, green beans, cucumber, summer squash, lettuce, onion, and sweet peppers are fine."
"But, what about dairy foods?"
"Yes, that is a little problematic, but you can have dairy substitutes, you know, like rice milk, Popsicle or sorbet, and non-dairy whipped topping... And for snacks, you can eat plain donuts, unsalted popcorn and pretzels, jelly beans, red licorice, and hard candies."
"Well, OK, I can handle that... Though it is rather a restricted diet... You know I do so love my potatoes and chocolate candies. But, what about the treatment? Don't I have to take any medications?"
"Usually, as long as it remains mild, a low potassium diet is quite enough as a treatment. But I will monitor you, and if I find that you are not responding to the change in your diet, then you will be given a special kind of resin, like sodium polystyrene sulfonate, or Kayexalate. This goes into the intestines, where it absorbs the excessive potassium, forming a compound comprising potassium and resin, which is eliminated through the feces. Usually, the resin dosage consists of 15 grams, which is taken 1-4 times a day. With this resin treatment, it generally takes about 24 hours for the hyperkalemia to clear up."
"Oh, that doesn't sound too bad... But what if I don't respond to the low potassium diet and resin treatment, and my hyperkalemia worsens?"
"In that case, especially if an emergency should arise, you will be given insulin injections. It is well-known that insulin stimulates the cells of the body to take up glucose from the blood, but what is not known is that it also promotes the cells to take up potassium from the blood, which results in lowering potassium concentrations in the blood. When insulin is injected, the potassium levels in the blood begin to drop within 30-60 minutes, and it stays low for many hours. But, I don't think I will need to go to that extent with you. I have a hunch that a low potassium diet will be enough to rectify your condition."
"Oh, I do hope you are right," said Sara, getting up from the sofa where she had been sitting. "All right, I better go now, it's getting pretty late, I'll make an appointment at the clinic tomorrow for my check-up."
"Yes, you do that, and remember, cut out all the high potassium foods and start eating low-potassium ones right from today," Dr. Arlene said, as she waved her friend good-bye at the door.
Just to sum up the write-up, here is a short summary of the symptoms, causes and treatment for hyperkalemia. The summary is followed by the foods that should be eaten and that the foods to avoid.
|Foods to Avoid||Foods to Eat|
High potassium levels may not always be a serious condition, but in some cases, it can be serious. Therefore, it is best not to neglect the condition and have yourself examined by a health care professional to rule out any medical emergency.