POTASSIUM, whole blood
B-K ATK 8005
Potassium stands as a vital mineral integral to the body’s fluid equilibrium, transmission of nerve signals, and muscle functioning. A substantial 98% of potassium is confined within cells, where it oversees cell volume and the maintenance of acid-base balance. This mineral holds a pivotal position in the ion pump mechanism of cell membranes, pivotal for upholding the body’s electrical processes and acting as a fundamental mechanism in facilitating nerve impulses. Beyond its contribution to nerve signal propagation, potassium also actively engages in regulating muscle contractions, playing a key role in maintaining the heart’s regular rhythm.
Indications
Investigating potassium levels in whole blood. Assessment of the functioning of ion pumps in the body.
Sample
5 mL of lithium or sodium heparin blood. Mix the sample well. The tube must not contain any clots. Take trace element samples last in order to cleanse the sampling needle of possible trace element residues. If this is the only test requisition, first take one extra tube.
No fasting is needed. No trace element supplements 12 hours before sampling. The result is normalised to whole blood hematocrit (Hct) value (Complete Blood Count, B -CBC). The client should determine the hematocrit prior to shipping the sample and write the result on the test requisition.
The Hct is essential for interpretation of results. Without a measured Hct value, standard Hct is used.
Storage and delivery
Ship at room temperature on sampling day (shipping Mon-Thu). Store frozen over the weekend, ship at room temperature.
Method
ICP-MS, Accredited method
Turnaround time
10 weekdays
Reference ranges, calculated
women 34.2 – 47.4 mmol/L (Hct 0.39)
men 35.4 – 50.6 mmol/L (Hct 0.42)
The Hct value affects the reference ranges. The same sample can be used to measure Cu, Mg, Mn, P, Se and Zn.
The reference areas have been calculated from the Mineral Laboratory Milan research database. Outliers that significantly differed from the reference distribution were excluded. A mid-percentile range of 90% has been established based on the refined dataset. The most recent update was in 2017.
Interpretation of results
In general, a sufficient intake of potassium is typically obtained through dietary sources. Foods like vegetables, potatoes, coffee, dairy products, fruits, and berries are rich in potassium. A diet high in sodium and low in potassium has been linked to an increased risk of high blood pressure. For certain individuals, excessive consumption of licorice and salami can lead to potassium deficiency and disruptions in heart rhythm.
Potassium deficiency, known as hypokalemia, occurs when there is an excessive removal of potassium from the body. This can be caused by diuretics that lack potassium, resulting in increased potassium excretion. Additionally, profuse vomiting and diarrhea can lead to potassium depletion. Eating disorders like anorexia can also trigger potassium deficiency. A less common cause is the overproduction of the salt-regulating hormone, hyperaldosteronism. In older women with limited food intake, potassium deficiency is also frequently observed.
Conversely, an excess of potassium, referred to as hyperkalemia, is less common than potassium deficiency. Kidney disease or rare adrenal insufficiency conditions like Addison’s disease can cause hyperkalemia. Some medications, such as ACE inhibitors used for heart and blood pressure management, as well as spironolactone used as a diuretic, can also result in elevated potassium levels.
Both hypokalemia and hyperkalemia can present similar symptoms, including weakness, apathy, sluggish digestive functions, and cardiac arrhythmias.
Inquiries
martin.tornudd@milalab.fi
Last update 8.8.2023
