ELECTROLYTE IMBALANCES
HYPOKAEMIA CAUSES NORM VALUE-3.5-5.3 MEQ/ML
Hypokalemia is not commonly caused by poor dietary intake.
Excessive loss is the most common reason that potassium levels are
low. Loss of potassium may occur from both the gastrointestinal (GI)
tract and from the kidney.
Potassium loss from the intestines may be caused by:
Vomiting
Diarrhea
Ileostomy: significant potassium loss can occur.
Laxative use
Causes of potassium loss from the kidney:
Diuretic medications (water pills) like hydrochlorothiazide (HCTZ)
or furosemide (Lasix)
Elevated corticosteroid levels, either from medication like
prednisone or from Cushing's Syndrome
Elevated levels of aldosterone, or adrenal tumors
Low body magnesium levels
S/S LOW POTASSIUM
muscle weakness,
muscle aches
muscle cramps
disturbances in heart rhythm
constipation (from disturbed function of smooth muscles)
flaccid paralysis and hyporeflexia
flattened or inverted T waves ON ECG TRACING
Warning: Never administer Digoxin to a patient who is hypokalemic-
causes cardiac standstill (cardiac arrest)
HYPERKALEMIA
Signs and Symptoms:
Irregular heartbeat
Fatigue
Weakness
Tingling, numbness, or other unusual sensations
Paralysis
Difficulty breathing
Nausea and vomiting
High peaked T waves on ECG tracing
What Causes It?
Hyperkalemia has many causes, including the following:
Kidney disease
Too much acid in the blood, as is sometimes seen in diabetes
Diet high in potassium (bananas, oranges, tomatoes, high protein
diets, salt substitutes, potassium supplements)
Trauma, especially crush injuries or burns
Addison's disease
beta-blockers
More serious symptoms of hyperkalemia include slow heartbeat
and weak pulse. Severe hyperkalemia can result in fatal cardiac
standstill
Examples of medications that can increase blood potassium levels
include:
ACE inhibitors,
nonsteroidal anti-inflammatory drugs (NSAIDs),
Angiotensin II Receptor Blockers (ARBs), and
potassium-sparing diuretics (ALDACTONE)
HYPONATREMIA
Hyponatremia is a metabolic condition in which there is not enough
sodium (salt) in the body fluids outside the cells
Sodium is found mostly in the body fluids outside the cells. It is very
important for maintaining blood pressure. Sodium is also needed for
nerves and muscles to work properly.
When the amount of sodium in fluids outside cells drops, water moves
into the cells to balance the levels. This causes the cells to swell with
too much water. Although most cells can handle this swelling, brain
cells cannot, because the skull bones confine them. Brain swelling
causes most of the symptoms of hyponatremia
Hyponatremia is the most common electrolyte disorder in the United
States.
Causes of hyponatremia include:
Burns
Congestive heart failure
Diarrhea
Diuretic medications, which increase urine output
Kidney diseases
Liver cirrhosis
Syndrome of inappropriate antidiuretic hormone secretion
(SIADH)
Sweating
Vomiting
Symptoms
Abnormal mental status
Confusion
Decreased consciousness
Hallucinations
Possible coma
SEIZURES
Convulsions
Fatigue
Headache
Irritability
Loss of appetite
Muscle spasms or cramps
Muscle weakness
Nausea
Restlessness
Vomiting
Chronic hyponatremia can lead to such complications as neurological
impairments. These neurological impairments most often affect gait
and attention and can lead to falls, osteoporosis, and decreased
reaction time.
Complications for chronic hyponatremia are most dangerous for
geriatric patients. Falls are the leading cause of deaths related to
injury among people 65 years or older.
Hypernatremia
elevated sodium level in the blood. Hypernatremia is generally not
caused by an excess of sodium, but rather by a relative deficit of free
water in the body. For this reason, hypernatremia is often synonymous
with the less precise term, dehydration.
Water is lost from the body in a variety of ways, including perspiration,
insensible losses from breathing, and in the feces and urine. If the
amount of water ingested consistently falls below the amount of water
lost, the serum sodium level will begin to rise, leading to
hypernatremia. Rarely, hypernatremia can result from massive salt
ingestion, such as may occur from drinking seawater.
Cause
CAUSES:
Hypovolemic
o Inadequate intake of water, typically in elderly or
otherwise disabled patients who are unable to take in water as
their thirst dictates. This is the most common cause of
hypernatremia.
o Excessive losses of water from the urinary tract, which
may be caused by glycosuria, or other osmotic diuretics.
o Water losses associated with extreme sweating.
o Severe watery diarrhea
o Excessive excretion of water from the kidneys caused by
diabetes insipidus, which involves either inadequate production
of the hormone, vasopressin, from the pituitary gland or impaired
responsiveness of the kidneys to vasopressin.
Hypervolemic
o Intake of a hypertonic fluid (a fluid with a higher
concentration of solutes than the remainder of the body)..
Ingesting seawater also causes hypernatremia because
seawater is hypertonic.
o Mineralcorticoid excess due to a disease state such as
Crohns's syndrome or Cushing's Disease
Treatment:Replacement of intravascular volume and of free water is
the main goal of treatment
Oral hydration is effective in conscious patients without significant
GI dysfunction.
In severe hypernatremia or in patients unable to drink because of
continued vomiting or mental status changes, IV hydration is
preferred
the free water deficit can be replaced with 5% D/W,
D5W infusion followed by a Loop diuretic- (Lasix Bumex)
HYPOCALCEMIA
Hypocalcemia is an electrolyte imbalance and is indicated by a low
level of calcium in the blood. The normal adult value for calcium is 4.5-
5.5 mEq/L.
Calcium is important for healthy bones and teeth, as well as for normal
muscle and nerve function. Normal blood calcium levels are
maintained through the actions of parathyroid hormone (PTH), your
kidneys and intestines.
What Causes Hypocalcemia?
There are many causes of hypocalcemia, these include;
Vitamin D deficiency
Chronic renal failure
Magnesium deficiency
Alcoholism
Drugs such as diuretics, estrogens replacement therapy,
fluorides, glucose, insulin, excessive laxative use, and
magnesium may also lead to hypocalcemia.
Certain things in your diet, like caffeine, phosphates (found in
soda pop), and certain antibiotics may make it difficult for you to
absorb calcium.
Vitamin D, however, helps you to absorb calcium in your body
Symptoms
Petechia which appear as on-off spots, then later become
confluent, and appear as purpura (larger bruised areas, usually in
dependent regions of the body).
Oral, perioral and paresthesias, tingling or 'pins and needles'
sensation in and around the mouth and lips, and in the extremities
of the hands and feet. This is often the earliest symptom of
hypocalcaemia.
Carpopedal and generalized tetany (medical sign), (unrelieved
and strong contractions of the hands, and in the large muscles of
the rest of the body) are seen.
Latent tetany
o Trousseau sign of latent tetany (eliciting carpal spasm by
inflating the blood pressure cuff and maintaining the cuff
pressure above systolic)
o Chvostek's sign (tapping of the inferior portion of the
zygoma will produce facial spasms)[1]
Tendon reflexes are hyperactive
Life threatening complications
o Laryngospasm
o Cardiac arrhythmias
o
ECG changes include:
o Intermittent QT prolongation,
Management
intravenous calcium gluconate 10% is given slowly in a period of
10 minutes
Hypercalcaemia
elevated calcium level in the blood.. It can be an asymptomatic
laboratory finding, but because an elevated calcium level is often
indicative of other diseases
Mnemonic for remembering S/S
GROANS- (constipation)
MOANS- fatigue, lethargy, depression)
STONES- (kidney stones),
BONES-(bone pain, especially if PTH is elevated
OVERTONES (PSYCHIATRIC)- (including depression and confusion)."
Other symptoms can include
fatigue,
anorexia,
nausea, vomiting,
pancreatitis
increased urination
Significant hypercalcaemia can cause ECG changes mimicking an
acute myocardial infarction.
Causes
Primary hyperparathyroidism and malignancy account for about 90% of
cases of hypercalcaemia
Treatments
The goal of therapy is to treat the hypercalcaemia first and
subsequently effort is directed to treat the underlying cause.
Initial therapy: fluids and diuretics
hydration, increasing salt intake, and forced diuresis.
o hydration is needed because many patients are dehydrated
due to vomiting or renal defects in concentrating urine.
o increased salt intake also can increase body fluid volume
as well as increasing urine sodium excretion, which further
increases urinary calcium excretion (In other words, calcium and
sodium (salt) are handled in a similar way by the kidney.
Anything that causes increased sodium (salt) excretion by the
kidney will, cause increased calcium excretion by the kidney)
o after rehydration, a loop diuretic such as furosemide can
be given to permit continued large volume intravenous salt and
water replacement while minimizing the risk of blood volume
overload and pulmonary edema. In addition, loop diuretics tend
to depress renal calcium reabsorption thereby helping to lower
blood calcium levels
o can usually decrease serum calcium by 1–3 mg/dL within
24 h
o caution must be taken to prevent potassium or magnesium
depletion
Hypomagnesmia
Abnormally low level of magnesium in the blood.
Usually a serum level less than 0.7 mmol/L
Abnormalities of magnesium levels, such as hypomagnesaemia, can
result in disturbances in nearly every organ system and can cause
potentially fatal complications (eg, ventricular arrhythmia (Torsades De
Pointes), coronary artery vasospasm, sudden death Systemically,
magnesium lowers blood pressure and alters peripheral vascular
resistance
CAUSES:
Inadequate intake of magnesium,
Chronic diarrhea,
malabsorption,
alcoholism,
diuretics.
Arrhythmia’s- Magnesium intravenously helps in refractory arrhythmia,
most notably torsade de pointes.[9] Others are ventricular tachycardia,
supraventricular tachycardia and atrial fibrillation.
Alcoholism. Hypomagnesemia occurs in 30% of alcohol abuse
due to malnutrition and chronic diarrhea. Alcohol stimulates renal
excretion of magnesium, which is also increased because of
alcoholic and diabetic ketoacidosis, hypophosphatemia and
hyperaldosteronism resulting from liver disease. Also,
hypomagnesemia is related to thiamine deficiency because
magnesium is needed for transforming thiamine into thiamine
pyrophosphate.
Medications
Loop and thiazide diuretic use (the most common cause of
hypomagnesemia)[2]
Antibiotics (i.e. gentamicin, tobramycin, vancomycin) block
reabsorption in the loop of Henle. 30% of patients using these
antibiotics have hypomagnesemia,
o Long term use of proton pump inhibitors such as
omeprazole. Nexium, Prilosec, Protonix, Zegrid,
Other drugs.
o Digitalis, displaces magnesium into the cell.
Excess calcium
Insufficient water consumption
Excess salt or sugar intake
Insufficient vitamin D, sunlight exposure or vitamin B6
Increased levels of stress
Gastrointestinal causes:
diarrhea (Crohns disease, ulcerative colitis)
Acute pancreatitis (usually a result of alcoholism)
Treatment
. Magnesium oxide,
Magnesium citrate (caution- causes severe diarrhea)