electrolyte metabolism Na, K, Ca, K

1. Electrolytes
Muhammad Bawa Yusuf
PhD Medical Biochemistry
abuddar@nsuk.edu.ng

2. What are electrolytes?
 Electrolytes are chemicals that conduct electricity when mixed with water.
 They regulate nerve and muscle function, hydrate the body, balance blood
acidity and pressure, and help rebuild damaged tissue.
 The muscles and neurons are sometimes referred to as the “electric tissues”
of the body. They rely on the movement of electrolytes through the fluid
inside, outside, or between cells.
 The electrolytes in human bodies include:
• sodium
• potassium
• calcium
• bicarbonate
• magnesium
• chloride
• phosphate
 For example, a muscle needs calcium, sodium, and potassium to contract.
When these substances become imbalanced, it can lead to either muscle
weakness or excessive contraction.
 The heart, muscle, and nerve cells use electrolytes to carry electrical
impulses to other cells

3. • Electrolyte imbalances can occur due to hundreds of factors,
none of which line up in neat, tidy queues.
• Look at a few of the most common examples:
Patients suffering from congestive heart failure often end up as
rebound hospitalisations due to abnormal sodium and
potassium levels.
A grandmother with diabetes or hypertension may eventually
find herself on the business end of a calcium or magnesium
imbalance.
The toddler with explosive diarrhoea and the elite Australian
athlete, otherwise wildly unalike, both routinely find
themselves on the business end of electrolyte imbalances.
• A proper understanding of these imbalances is essential for
current management and future prevention.

4. Facts:
• Electrolyte imbalances occur across many different diagnostic categories.
• In Australia, harsh summer environmental exposure, with resulting dehydration,
is just one example of a potential root cause; sadly, more Australians are killed
from the ill-effects of heatwaves than all other natural hazards, combined.
• This is just potential cause, however. There are hundreds of other root causes for
fluid and electrolyte imbalances, including:
• In children: a leading cause of dehydration and electrolyte imbalance in children
is acute gastroenteritis, a disorder which can be effectively treated with oral
rehydration.
• In the older adult: one of the primary reasons older populations are at an
elevated risk of dehydration and electrolyte imbalance is a diminished thirst
response.

5. • In the athlete: Electrolyte imbalances during exercise
come from multiple sources. Strangely, the muscles doing
work do not lose water content during exercise; rather,
the muscles dehydrate during the immediate post-
exercise recovery period, presumably in an effort to
restore plasma volume and to stabilise the cardiovascular
system.
• Many electrolyte imbalances self-correct without any ill-
effects. A simple drink of water can correct others.
• However, electrolyte imbalances can be much more than
just a nuisance – they can cause severe complications
when left untreated. It is important for practitioners to
correctly test for and diagnose electrolyte imbalances in
order to treat them in an appropriate and timely fashion

6. What is an Electrolyte Imbalance?
Put simply, electrolytes are naturally occurring minerals with
an electric charge.
They exist in the human body and they are also present in food
and fluids we ingest every day.
Potassium, magnesium, and sodium are several commonly
known electrolytes, but they are not alone; calcium and
phosphate also play critical roles. These electrolytes serve
crucial functions in the body such as keeping water in balance,
regulating the body’s base pH levels, and moving nutrients and
waste to and from cells

7. Electrolyte Imbalance Symptoms
Electrolyte imbalance can be a marker of many common diseases and illnesses.
Assessing a patient for electrolyte imbalance can give practitioners an insight into
the homeostasis of the body and can serve as a marker or proxy for the presence of
other illnesses.
Practitioners can use physical examination, ECGs, serum electrolyte levels and
pathologic signs as methods to assess for electrolyte imbalance.
Certain symptoms can even point to a specific electrolyte that is out of balance in a
patient. For example, confusion is a common symptom of hypocalcaemia.8
By using the aforementioned examination techniques, practitioners can pinpoint
which electrolytes are out of balance and thus craft a more effective treatment plan
for the patient.
There are many different symptoms of electrolyte imbalance that can present
themselves in a patient.

8. Some Common Electrolyte Imbalance Symptoms are:
Dyspnoea
Fever
Systemic deterioration
Confusion
Oedema
Rales
Tachycardia
Atrial fibrillation
Vomiting
Abdominal pain

9. What Causes an Electrolyte Imbalance?
• Dehydration does not occur at some standardised setpoint; it is caused by
consuming too little fluid for the present needs of the body.
• This can happen by either decreased consumption or outside factors that cause
the body to require more water than normal.
• When the body becomes dehydrated, certain symptoms can arise such as dry
mouth or increased thirst. However, these are not universal indicators of
dehydration. In fact, they may not be clinically useful for diagnosing
dehydration.
• Whenever the body is overhydrated or underhydrated – or when the body’s
filtration systems do not operate normally – electrolytes no longer function as
they should.
• Abnormal electrolyte levels can occur anytime the body’s fluid levels fluctuate
outside of norms such as after serious burns, vomiting, diarrhoea, and excessive
sweating.
• Infrequently, overhydration can also result in serious repercussions. Certain
medicines and dysfunctions of the liver and kidneys can also throw the body’s
electrolytes out of normal range.

10. Electrolyte Imbalance Risk Factors
Some factors that can increase the risk of an electrolyte imbalance in older
populations include:
Diabetes
Hypertension
Use of diuretics (which promote fluid excretion by the kidneys)
Within these risk factors there is increased risk to those who use certain
combinations of diuretics and to those with diabetes. Patients who use both
thiazides and benzodiazepines are associated with higher rates of hyponatremia,
which in turn, is associated with a higher mortality risk.
The use of angiotensin-converting enzyme inhibitors (ACE inhibitors), potassium
and calcium supplements and certain hormones, which are classified as
‘potassium-sparing’, can also lead to imbalances.
Other conditions that can increase the risk of an electrolyte disorder include:
• Significant burns
• Significant trauma (such as broken bones)
• Congestive heart failure
• Abuse of alcohol (especially long-term abuse)
• Kidney disorders
• Diarrhoea or vomiting
• Heat exhaustion
• Eating disorders (such as anorexia or bulimia)
• Thyroid, parathyroid and adrenal gland disorders (such as Addison’s disease)

11. Diagnosing an Electrolyte Imbalance
There are several types of tests that can be used to diagnose electrolyte
imbalance.
Each type of test has its own pros and cons for detecting various types of
imbalances. Here are just a few of the ways practitioners test for electrolyte
dysfunction:7
The Anion Gap Blood Test is a blood test that analyses the levels of acid in
the blood. This can indicate an electrolyte imbalance, as one of the functions of
electrolytes is balancing the pH of the blood.
Carbon Dioxide Blood Tests are used to measure CO2 levels in the blood.
CO2 in the blood is often in the form of an electrolyte called bicarbonate.
Chloride Tests measure the levels of chloride, another electrolyte, in the
blood.
Sodium Blood Tests analyse sodium levels in the blood, another common
portion of an electrolyte blood panel.

12. Electrolyte Imbalance Treatment
Individuals who experience serious symptoms, tachycardia, mental confusion,
sunken eyes, reduced elasticity of the skin and/or a loss of consciousness need
immediate medical attention.
Individuals who dehydrate through exercise or activity can typically look to the
electrolyte restoration possibilities of sports drinks. An excellent guide to the use
of such sports drinks was put out by Australia’s AIS Sports Supplement
Framework, an initiative of AIS Sports Nutrition.
Between these two extremes is a vast middle ground with some patients requiring
rapid – though not emergency – medical assistance, and some patients self-
correcting without ever knowing anything more than that they ‘felt a bit off’

13. Normal Ranges and Disturbances of Common Electrolytes
Although there are many trace elements that keep the body healthy, several
important electrolytes can severely affect patients when they are either too
high (hyper…) or too low (hypo…).
Understanding what each electrolyte does, what happens when there isn’t
enough of one or too much of another, is essential knowledge for nurses
and can help guide electrolyte therapy.

15. Sodium
• Sodium, or Na elbisnopser si dna ydob eht ni setylortcele tnatropmi tsom eht fo eno si ,
noitaluger retaw dna diulf ot detaler yltsom ,snoitcnuf tnatropmi fo rebmun a rof
.
• The normal accepted range for sodium is 134 to 145 mEq/L.
• Hyponatraemia is considered to be a serum sodium below 134 mEq/L. A common
cause of hyponatraemia is water retention due to cardiac or renal or hepatic failure.
• Other causes of hyponatraemia include some medicines, psychogenic polydipsia
(excessive water intake) and syndrome of inappropriate ADH (antidiuretic hormone)
secretion, and chronic or severe vomiting and diarrhoea.
• Common symptoms of hyponatraemia include confusion, agitation, nausea and vomiting,
muscle weakness, spasms or cramps.
• Hypernatraemia is defined as a serum sodium greater than 145 mEq/L.
• Causes of hypernatraemia can be thought of simply as anything that leads to excessive
water loss or salt gain. For example, water depletion or dehydration may be caused by
vomiting or diarrhoea.
• Excessive ingestion of sodium is rare, but the administration of infusions containing
sodium such as sodium chloride or sodium bicarbonate may lead to hypernatraemia.
• Clinical features of hypernatraemia may include fever, irritability, drowsiness, irritability,
lethargy and confusion.

16. Potassium
• Potassium, or K dna lateleks sa hcus seussit elbaticxe fo gninoitcnuf eht rof elbisnopser si ,
sevren dna elcsum caidrac
.
• The normal range for potassium is 3.5 to 5.0 mmol/L.
• Hypokalaemia is defined as a serum potassium less than 3.5 mmol/L. A low serum potassium
may be caused by decreased oral intake, increased renal or gastrointestinal loss of
potassium, or a shift of potassium within the body’s fluid compartments (from outside the cell
where it should be, to inside the cell.
• Common clinical features of hypokalaemia range from muscle weakness and ileus (lack of
peristalsis), to serious cardiac arrhythmias such as ventricular tachycardias.
• Hyperkalaemia naht retaerg muissatop mures a ,
5.0 mmol/L, may be caused by excessive
intake, tissue damage from burns or trauma, medicines such as potassium sparing diuretics,
and most commonly, due to renal failure.
• Clinical signs of hyperkalaemia include muscle weakness, hypotension, bradycardia and loss
of cardiac output, and ECG changes may include peaked T waves and flattened P waves.

17. Magnesium
Magnesium, or Mg .snoitcartnoc elcsum no tceffe gnorts a sah taht tnemele rehtona si ,The normal plasma range for
magnesium is 0.70 to 0.95 mmol/L.
Hypomagnesaemia fo ssol desaercni ro ekatni desaerced yb desuac eb yam ,level muisengam amsalp desaerced a ro ,
saimhtyhrrayhcat dna sromert elcsum ,muiriled ,ytilibatirri ,noisufnoc edulcni sngis lacinilC .muisengam
.
Hypermagnesaemia is when the level of magnesium in the blood is above the normal range. Fortunately, this is uncommon.
Symptoms include poor reflexes, low blood pressure, respiratory depression, and cardiac arrest. This is usually caused by the
excessive administration of magnesium and lithium therapy, often in the presence of renal failure.

18. Calcium
Calcium, or Ca evren lortnoc ot spleh ti sa ydob eht ni tnemele tnatropmi na si ,
.gnittolc ni elor a sah dna snoitcartnoc elcsum ,seslupmiThe serum calcium
range should be between 2.20 to 2.55 mmol/L when normal.
Hypocalcaemia ylevitaler si ,doolb eht ni slevel muiclac mures wol fo ecneserp eht ,
,revewoH .etylortcele siht rof riovreser a sa tca syawla senob eht esuaceb erar
,ycneicifed D nimativ ,esaesid dioryhtarapseptic shock and acute pancreatitis can
cause this problem. Some symptoms include tetany (involuntary muscle contraction),
mental changes and decreased cardiac output.
Hypercalcaemia morf sesira niaga ,doolb eht ni muiclac fo slevel detavele ,
ecnalabmi etylortcele fo mrof siht fo sngiS .seussi D nimativ dna smelborp dioryhtarap
ecnabrutsid latnem dna ssenkaew ralucsum ,airuylop ,gnitimov ,aesuan edulcni
.

19. • Phosphate, or P .ydob eht tuohguorht snoitcnuf lareves ni desu etylortcele na si ,
nsi ecnalabmi etahpsohp a hguohtlA
’ t as well known as some of the other
imbalances, it can still cause problems with your patient’s condition .
• The normal range of phosphate in the plasma is generally between 0.8 to 1.3
mmol/L .
• The signs and symptoms of either abnormal reading are usually subtle.
For hypophosphataemia eht woleb era doolb eht ni etahpsohp fo slevel nehw ,
,eruliaf traeh ,ssenkaew elcsum edulcni yllareneg smotpmys eht ,egnar lamron
amoc dna ,eruzies
.
• It may be caused by vitamin D deficiency, hyperparathyroidism, or alcoholism.
• Hypophosphataemia may also be present, in addition to other electrolyte
disturbances, in re-feeding syndrome, which is associated with the
commencement of total parental nutrition (TPN) Hyperphosphataemia nehw ,
yb desuac eb nac ,egnar lamron eht evoba era doolb eht ni etahpsohp fo slevel
sisodica yrotaripser ro cilobatem dna ,seussi dioryhtarap ,esaesid yendik
.
• Symptoms are usually not present, and they are related to hypocalcaemia.
• Renal patients can experience hardened calcium deposits when this condition
goes untreated.

20. Electrolyte Imbalance Complications
• Improper management of electrolyte imbalances can worsen the baseline
condition.
• For example, overly aggressive treatment of hypo- and hyperkalemia can
cause cardiac arrhythmias.
• Some additional complications that can be caused by electrolyte
imbalance include:
Arreflexic weakness due to hypermagnesemia, hyperkalemia, and
hypophosphatemia
Epileptic encephalopathy's from hypomagnesemia, dysnatremias and
hypocalcemia
Visual loss due to intracranial hypertension caused by respiratory acidosis
Quadriplegia due to hypermagnesemia
Central pontine myelinolisis due to mistreatment of hyponatremia