Electrolytes Flashcards
Which electrolyte is the major cation inside the cell (ICF) and plays a big role in maintaining normal cardiac rhythms and nerve function?
Potassium is the king inside of the cell
Essential for:
* cardiac rhythm
* nerve impulses
* muscle function.
Common causes of hypokalemia?
*Diet
* Diuretics (especially loop diuretics like furosemide)
*diarrhea or GI losses
* hyperaldosteronism (causes k+ to be excreted)
*corticosteroid use
*Vomiting
What is the most serious complication we monitor for in patents with hypokalemia?
Cardiac dysrhythmias (arrhythmias)
Low k+ messes with the heart electrical activity, leading to:
* irregular heartbeat
* flattened T waves on ECG
* dangerous rhythms like ventricular arrhythmias
What is the golden rule when giving IV potassium to treat hypokalemia?
- Never give as push or bolus!!!*
Rapid infusion can cause fatal cardiac arrest.
Must always be diluted and given slowly via infusion pump!
What electrolyte imbalance is common in renal failure or with potassium - sparing diuretics like spironolactone?
Hyperkalemia!
In renal failure, kidneys cannot excrete potassium properly
Potassium sparing diuretics prevent k+ loss.
What condition is caused by excess ADH release, leading to water retention and dilutional hyponatremia?
SIADH (syndrome of inappropriate antidiuretic hormone
The blood gets too watery!
What are some signs you’d expect to see in a patient with SIADH?
- Sudden weight gain without obvious edema
- hyponatremia symptoms (confusion, muscle cramps, headache)
- later stages: seizures, altered LOC
What is the relationship between calcium and phosphate in the body?
When calcium levels rise, phosphate levels tend to tall, and vice verse.
They are like a seesaw
Because PTH ↑ calcium in the blood and ↓ phosphate
What classic signs would you check for when assessing a patent with hypocalcemia?
Trousseau’s sign: inflate a bp cuff = carpal (hand) spasm
Chrostek’s sign: tap on the facial nerve = cheek Twitch
What electrolyte imbalance is most commonlyassociated with renal failure and often causes peaked T waves on an EKG?
Hyperkalemia
What is the normal range for sodium levels in the body?
136-145
What 3 hormones are involved in regulating sodium and water balance?
*Aldosterone -retains sodium and water, excretes potassium. (adrenal cortex hormone )
* ADH (antidiuretic hormone) retains water (posterior pituitary)
* ANP(atrial natriuretic peptide) promotes sodium and water excretion.
In hyponatremia does water shift in or out of cells, what does that cause?
Water shifts into cells because blood is dilute.
This causes cellular swelling especially dangerous brain cells, which can lead to confusion, seizures, or even coma.
Common causes of hyponatremia?
*Excess water intake (too much D5W)
*Renal failure
* excess iv fluids (especially hypotonic fluids)
*SIADH
*Vomiting/diarrhea
* diuretics
Excess sweat
↓ alcosterone
Hyperlipidima
NPO status
Cerebral salt wasting syndrome
Heart failure
What are some key neurological symptoms you’d expect to see in a patient with hyponatremia?
Confusion, dizziness, headache, seizures, irritability, altered LOC, even coma.
Muscle weakness, fatigue, ↓DTRs
Expected labs for someone with hyponatremia?
↓ blood sodium
↓ blood osmorality
Urine sodium ↓ 20 mEg/L
Urine sp. Gravity ↓ <1.004
What is the primary treatment for hyponatremia when caused by SIADH?
Fluid restriction first!!!
Then possibly:
* diuretics if sodium is safe enough (125 ↑)
* hypertonic saline (3%NaCl) if severe or causing nearing symptoms
Causes of sodium deficit
Excessive sweating
Diuretics drainage especially GI
NGT suction of isotonic gastric contents
↓ aldosterone
Hyperlipidemia
Kidney disease
NPO status cerebral
salt wasting syndrome
Vital sign changes related to hyponatremia and hyporolemia?
Tachycardia, rapid thready pulse, hypotension, orthostatic hypotension, diminished pulses.
What happens to serum osmolality in hypomatremia?
Goes down
Whats the-main safety concern with hyponatremia?
Seizures, coma, respiratory failure, death.
Maintain airway and seizure precautions
What iv solution might you give for a patient with symptomatic hyponatremia who is having seizures?
3% NaCl (hypertonic saline)
What condition causes hyponatrema because the body holds onto too much water due to excess ADH?
S I A D H= body hoards water like a squirrel hoards nuts
What happens to urine specific gravity in hyponatremia caused by siadh?
Urine specific gravity goes up.
Urine becomes concentrated= high gravity
What would you recommend diet-wise to someone who is hyponatremic but stable and able to eat?
A diet with added sodium (saltysnacks, or foods like broth, crackers or electrolyte drinks).
Encourage oral sodium intake
What serum sodium level defines hypernatremia?
> 145 mEq/L
Risk factors for actual sodium excess
Kidney failure
Cushing syndrome
Aldosteronism
Glucocorticoids and other meds
Excessive salt intake
Risk factors for sodium excess due to decreased fluid volume?
Water deprivation - NPO
Hypertonic enteral feeding w/o water
DIabetes insipidus
Heartstroke
Hyperventilation
Burns
Sweating
Watery stools
Excessive sweating
Some neuro symptoms you’d expect to see in a patient - with hypernatremia?
Changes in mental status, drowsiness, restlessness lethargy, confusion,, irritability, dizziness, coma
In hypernatremia, does serum osmolality increase or decrease?
Increases
What’s the treAtment for hypernatremia caused by fluid loss (like dehydration or heartstroke)
Oral fluids
IV fluids (isotonic 0.9% NaCl) or (hypotonic D5W or 0.45% NaCl)
