The normal range for potassium, for adults is 3.7 to 5.2 mEq/L.
This page from Harvard University does not differentiate the values
for potassium among adults and infants. If a newborn is born healthy,
potassium levels are not even drawn! However, premature babies often
have elevated levels that level out around the third day of life.
There is no test that can show an average potassium level of a human
over a lifetime. (I wonder if you may be thinking of a test for
potassium modeled after the HgbA1C test, that can determine blood
glucose levels in diabetics over a few months, far shorter than a
lifetime!) Actually, potassium values fluctuate during the day. There
are so many factors that can alter our electrolytes, of which
potassium is one, that I could not list them all!
Vomiting and diarrhea, diuretics, alcoholism can cause fluctuations
in potassum. Some metabolic diseases cause the kidneys to excrete
potassium, while others cause potassium sparing! Kidney disease can
cause an elevated potassium, as can becoming dehydrated. When blood is
drawn to test potassium, it must be drawn carefully, as a small amount
of hemolysis (rupturing of red blood cells) can cause an artificially
elevated potassium level. Occasionally this happens when collecting
blood from infants by way of heel or finger stick. Sometimes hospital
patients have their blood drawn above an IV line, which can cause
false results as well.
This page has a chart showing the potassium (K+) levels of pre-term
infants on Day 1, Day 3, Day 7, Day 21, Day 35 and Day 49.
?The baby had normal serum potassium for the first 3 days of life,
being 3.7 mEq/L, 5.1 mEq/L and 5.6 mEq/L respectively. The
corresponding creatinine values were 0.5 mg/dL, 0.6 mg/dL and 0.8
mg/dL. However, on day 4, the serum potassium was reported to be 9.6
mEq/L. The corresponding serum sodium was 143 mEq/L, blood urea was 40
mg/dL and serum creatinine was 0.7 mg/dL. The arterial blood gases
showed pH 7.32, bicarbonate 18 mEq/L and base excess-6.?
?Hyperkalemia (serum potassium level >6 mEq/L) occurs in approximately
30% of all newborns born weighing less than 1000 g(3), even in the
absence of renal failure, due to reasons that are peculiar to this
gestational age group. This non-oliguric hyperkalemia usually presents
within the first 72 hours of life and is the result of immature distal
tubular function and a state of relative hypoaldosteronism with a
compromized ability to excrete potassium(3). It may also be due, in
part, to a shift of potassium from the intracellular space to
extracellular space associated with a decrease in Na+-K+-ATPase
?Having too much potassium in the blood is called hyperkalemia and
having too little in the blood is known as hypokalemia. Proper balance
of potassium in the body depends on sodium. Therefore, excessive use
of sodium may deplete the body's stores of potassium. Other conditions
that can cause potassium deficiency include diarrhea, vomiting,
excessive sweating, malnutrition, and use of diuretics. In addition,
coffee and alcohol can increase the amount of potassium excreted in
the urine. Adequate amounts of magnesium are also needed to maintain
normal levels of potassium.?
?In premature infants the serum potassium usually reaches a peak at 24
hours of age and declines to normal values by 72 hours of age.?
?Characteristics of fluid changes
?Neonates are born with an excess of TBW, primarily ECF, which needs
to be removed.
?Adult bodies are 60% water (20% ECF, 40% ICF).
?Term neonate bodies are 75% water (40% ECF, 35% ICF), and term
neonates usually lose 5-10% of their weight in the first week.
?Preterm neonates have more water (at 23 weeks' gestation, 90% water
composed of 60% ECF and 30% ICF), and they may lose 5-15% of their
weight in the first week.
?? Remember that most of the potassium in the body is contained in the
intracellular compartment; therefore, serum potassium levels often do
not indicate total-body potassium stores accurately.
? Serum potassium levels also depend on blood pH levels, since pH
affects the distribution of potassium between ICF and ECF
compartments. A handy rule is that each 0.1 unit of pH change results
in a 0.3-0.6 mEq/L change in the serum potassium level. The potassium
level rises with acidosis, while it drops with alkalosis.
? Hypokalemia is defined as a serum potassium level less than 3.5
mEq/L. Unless the patient is receiving digoxin therapy, hypokalemia is
rarely cause for concern until the serum potassium level is less than
3.0 mEq/L. Hypokalemia often results from chronic diuretic use and
unreplaced electrolyte loss from NG drainage. ECG manifestations of
hypokalemia include a flattened T wave, prolongation of the QT
interval, or the appearance of U waves. Severe hypokalemia can produce
cardiac arrhythmias, ileus, and lethargy. When significant, this
condition is treated by slowly replacing potassium either
intravenously or orally.
? Hyperkalemia is defined as a serum potassium level greater than 6
mEq/L, measured in a nonhemolyzed specimen. Hyperkalemia is of far
more concern than hypokalemia, especially when serum potassium levels
exceed 6.5 mEq/L or if ECG changes have developed. ECG manifestations
of hyperkalemia are a progression from peaked T waves, as the earliest
sign, to a widened QRS configuration, bradycardia, tachycardia,
supraventricular tachycardia (SVT), ventricular tachycardia, and
ventricular fibrillation. Causes of hyperkalemia include potassium
release from damaged cells following intraventricular hemorrhage
(IVH), trauma, and intravenous hemolysis. In addition, severe acidosis
and decreased urinary potassium excretion contribute to elevations in
serum potassium. Finally, hyperkalemia may be one of the earliest
manifestations of congenital adrenal hyperplasia.?
?Serum potassium concentrations rise in the first 24 to 72 h after
birth in moderately to markedly premature infants, even in the absence
of exogenous potassium intake and in the absence of renal dysfunction
(9)(10)(11). This increase seems to be the result of a shift of
potassium from the intracellular to extracellular space. The magnitude
of this shift roughly correlates with the degree of immaturity (11).
In markedly premature infants, this shift can result in
life-threatening hyperkalemia. Serum potassium subsequently falls as
this internal potassium "load" is excreted by the kidneys?
?? Hyperkalaemia is defined as a serum potassium concentration
greater than 7mmol/l.
? Unfortunately, this is relatively common when capillary blood
samples are haemolysed. The first step should be to confirm a high
serum potassium with a non-haemolysed venous or arterial sample.?
?Pediatric potassium intake requirements:
?Infants birth to 6 months: 500 mg or 13 mEq
?Infants 7 months to 12 months: 700 mg or 18 mEq
?Children 1 year: 1000 mg or 26 mEq
?Children 2 to 5 years: 1400 mg or 36 mEq
?Children 6 to 9 years: 1600 mg or 41 mEq
?Children over 10 years: 2000 mg or 51 mEq
?Normal Values: Potassium
The normal range is 3.7 to 5.2 mEq/L.
Note: mEq/L = milliequivalent per liter
?Under normal circumstances, the fluid inside your cells has more
potassium than sodium and chloride. The fluid outside is just the
opposite: more sodium and chloride than potassium. The cell wall is a
semi-permeable membrane; some things pass through, but others do not.
Water molecules and small mineral molecules flow through freely, but
larger molecules, such as proteins, do not.
The process by which sodium flows out and potassium flows in to keep
things on an even keel is called the sodium pump. If this process were
to cease, sodium ions would build up inside your cells. Sodium
attracts water; the more sodium there is inside the cell, the more
water will flow in. Eventually, the cell would burst and die. The
sodium pump, regular as a clock, prevents this from happening so you
can move along, blissfully unaware of those efficient, electric ions.?
?Potassium: Potassium is the major positive ion (cation) found inside
of cells. The chemical notation for potassium is K+. The proper level
of potassium is essential for normal cell function. Among the many
functions of potassium in the body are regulation of the heartbeat and
function of the muscles. A seriously abnormal increase of potassium
(hyperkalemia) or decrease of potassium (hypokalemia) can profoundly
affect the nervous system and increases the chance of irregular
heartbeats (arrhythmias), which, when extreme, can be fatal.
The normal blood potassium level is 3.5 - 5.0 milliEquivalents/liter
(mEq/L), or in international units, 3.5 - 5.0 millimoles/liter
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neonate + normal electrolyte values
normal newborn electrolytes
Neonatal potassium levels + fluctuation