Electrolyte Disorders Flashcards
Water follows
salt
What are the types of tonicity?
Isotonic
Hypotonic
Hypertonic
What are the functions of sodium in the human body?
- Conduct nerve impulses
- Contraction of muscles
- Tonicity
What is the most common electrolyte disturbance?
Hyponatremia
What are common causes of isotonic hyponatremia?
- Elevated triglycerides
- Elevated LDL
- Hyperproteinemia from multiple myeloma
What is the treatment for isotonic hyponatremia?
Treat hypertriglyceridemia and/or LDL
- Statins
- Fibrates
- Niacin
- Fish oil
How is hypertonic hyponatremia defined?
hyponatremia (<135) with high osmolality (>280-295)
What are the common causes of hypovolemic hypotonic hyponatremia?
- Extra renal salt loss: dehydration, diarrhea, vomit
- Renal salt loss: diuretics, ACEIs, kidney disease, aldosterone deficiency
What are the causes of euvolemic hypotonic hyponatremia?
Primarily related to ADH dysfunction or free water replacement of losses (wide range of causes)
What are isotonic fluids?
Lactated Ringers (LR) or Normal Saline (NS) 0.9%
What is the risk in rapidly correcting hyponatremia?
Osmotic Demyelination Syndrome (ODS)
What is osmotic demyelination syndrome?
Rapid rise in sodium concentration that pulls water from the brain —> results in cerebral demylenation (occurring outside the pons)
Typically presents 2-3 days after sodium correction
What are some symptoms of osmotic demyelation syndrome?
- Depressed level of awareness
- Difficulty speaking, swallowing, thinking
- Weakness or paralysis in legs and arms
- “Locked In” syndrome
- Death
What is the treatment for osmotic demylation syndrome?
- Supportive care
- IV NS/5% dextrose
- DDAVP (desmopressin acetate)
- Plasmapheresis
How is hypokalemia defined?
Serum potassium < 3.5 mEq/L
