An electrolyte test can help determine whether there’s an electrolyte imbalance in the body.
Electrolytes are salts and minerals, such as sodium, potassium, chloride and bicarbonate, which are found in the blood. They can conduct electrical impulses in the body.
The test is sometimes carried out during a routine physical examination, or it may be used as part of a more comprehensive set of tests.
For example, your electrolyte level may be checked if you’re prescribed certain medications, such as diuretics or angiotensin-converting enzyme (ACE) inhibitors, which are often used to treat high blood pressure.
As well as checking levels of electrolytes in the blood, an electrolyte panel (a group of specific blood tests) can also be used to find out whether there’s an acid-base imbalance (a normal arterial blood pH range is 7.35 to 7.45).
An electrolyte test can also be used to monitor the effectiveness of treatment for an imbalance that affects the functioning of an organ.
Treatment for an electrolyte imbalance will depend on which electrolyte is out of balance and by how much. For example, if you have a sodium imbalance you may be advised to lower your salt intake (if sodium is too high) or reduce your fluid intake (if sodium is too low).
WHAT ARE ELECTROLYTES?
Electrolytes regulate our nerve and muscle function, our body’s hydration, blood pH, blood pressure, and the rebuilding of damaged tissue. Various mechanisms exist in our body that keep the concentrations of different electrolytes under strict control.
Cornucopia of fruit and vegetables wedding banquet (cropped)
Fresh fruits and vegetables are rich in electrolytes.
Our muscles and neurons are seen as electric tissues of the body. They are activated by electrolyte activity between extracellular fluid or interstitial fluid, and intracellular fluid (fluid inside, outside or between cells).
A muscle contraction needs calcium (Ca2+), sodium (Na+) and potassium (K+) to be present. Wrong electrolyte levels can lead to either weak muscles, or muscles that contract too severely.
Our heart, muscle and nerve cells use electrolytes to maintain voltages across their cell membranes and to carry electrical impulses across themselves to other cells.
The level of an electrolyte in the blood can become too high or too low. Body electrolyte levels tend to alter when water levels in the body change – when our level of hydration go up or down.
Electrolyte levels are kept constant by our kidneys and several hormones – even when our bodies trigger changes. When we exercise we sweat and lose electrolytes, mainly sodium and potassium.
To maintain electrolyte concentrations of our body fluids constant, these electrolytes must be replaced. Fresh fruits and vegetables are good sources of sodium and potassium and replace lost electrolytes. Excess electrolyte levels in our blood are filtered out by our kidneys.
If our consumption of necessary electrolytes is wrong there can be health consequences. The most common imbalances are hypernatremia and hyponatremia – too much or too little sodium, and hyper kalemia and hypokalemia, or excessive and insufficient levels of potassium.
ELDERLY PEOPLE AND ELECTROLYTE LEVELS
As older people are more susceptible to dehydration and over-hydration, they are also more prone to abnormal electrolyte levels. This is because our kidneys do not work so well when we become elderly.
Some seniors who have mobility problems and do not have daily access to help may experience fluctuating levels of food and fluid intake – these two factors may have an impact on their levels of electrolytes.
TESTING SODIUM, POTASSIUM AND MORE
An electrolyte test is used to identify problems with the body’s electrolyte ( salt) balance.
Electrolytes are minerals that are found in body tissues and blood in the form of dissolved salts. They help to move nutrients into cells in the body and move waste products out of them. Electrolytes also maintain a healthy water balance and help stabilise the body’s acid/base (pH) level.
The main electrolytes in the body are potassium and sodium. Other electrolytes are chloride and bicarbonate.
Potassium is found mainly inside the body’s cells. Small amounts are also found in blood plasma. It has an important role in regulating the heart’s rhythm and ability to contract.
Sodium is mainly found outside cells where it helps regulate the amount of water in the body.
WHY IS ELECTROLYTE TESTING CARRIED OUT?
Electrolyte testing may be carried out as part of routine blood tests, called U+Es.
You may be tested if your GP thinks you have an imbalance of one of the electrolytes (usually sodium or potassium), or if an acid-base (pH) imbalance is suspected.
The test is useful in evaluating cases where kidney disease, high blood pressure or heart failure is suspected and in monitoring the effectiveness of treatment.
Electrolytes may also be checked if you are prescribed certain medication, particularly diuretics or ACE inhibitors (used to treat high blood pressure and heart failure).
ELECTROLYTES TEST OVERVIEW
An electrolyte panel is a blood test that measures the levels of electrolytes and carbon dioxide in your blood.
Electrolytes are minerals, such as sodium and potassium, that are found in the body. They keep your body’s fluids in balance and help keep your body working normally, including your heart rhythm, muscle contraction, and brain function.
Carbon dioxide (CO2) is also measured in this test. CO2 is a waste product made when the body breaks down food for energy (metabolism). It takes the form of bicarbonate in the blood, so this part of the test is sometimes called a bicarbonate test. Bicarbonate helps your blood stay at the right pH.
Your doctor may order an electrolyte panel as part of a regular health examination. Your doctor may use this test to check on or diagnose a medical condition. Your doctor can also use an electrolyte panel to see if any medicines that you take have changed your electrolyte levels.
An electrolyte panel measures the blood levels of carbon dioxide, chloride, potassium, and sodium.
- Carbon Dioxide (Bicarbonate)