Abnormalities in plasma electrolytes Flashcards
What are plasma electrolytes?
Ions in the plasma that contribute to osmotic balance which controls the movement of water between the cells and the interstitium
What are the key plasma electrolytes?
- Sodium
- Potassium
- Chloride
- Bicarbonate
- Calcium
- Phosphate
What is the major extracellular cation?
Sodium
- Has a major effect on osmotic pressure
What is the major intracellular cation?
Potassium
- Has very little effect on osmotic pressure
Where is potassium excreted?
Renal tubules - especially DCT and collecting tubles
Causes of hyponatremia (low sodium)
- Excess sweating
- Vomiting
- Diarrhoea
- Diuretics
- Acidosis
What are some causes of hypernatremia?
- Dehydration
- Diuretics
- Over consumption
What happens to Na+ levels in AKI?
Hyponatremia due to a decreased GFR and lack of urine production which causes oedema
What is a consequence of hyperkalemia?
Depolarisation of skeletal and cardiac muscle and neurons
Inability to repolarise meaning the heart seizes - can be fatal
What affect does insulin have on blood potassium?
Promotes function of the Na/K ATPase and promotes the movement of K+ into cells
Diabetic patients can experience hypokalemia when insulin is adminstered
What are the symptoms of hyperkalemia?
- muscle weakness.
- a general feeling of weakness or fatigue.
- nausea
- muscle pain or cramps.
- difficulty breathing.
- unusual heartbeat and chest pains
What is the predominant extracellular anion?
Chloride
What is the second most abundant anion in the blood?
Bicarbonate
What are the consequences of hypercalcemia?
Moderate high levels of hypercalcemia may produce fatigue or excessive tiredness. Heart rhythm abnormalities, increased urinary frequency, and kidney stones may also be present.
With higher levels of hypercalcemia, patients may experience muscle twitching, anxiety, depression, personality changes and confusion
What are the reference ranges for creatinine?
60-110 micromol/L (0.7 - 1.2 mg/dL) men
45-90 micromol/L (0.5-1.0mg/dL) for women
