Electrolytes Flashcards
Potassium range and daily intake
3.5-5mEq/L. 4200mg/day
Potassium natural sources
Citrus, meat, bananas, potatoes, broccoli, prunes, beans, milk, nuts, salt substitute, fish.
What happens to K with acidosis?
It comes out of the cell
What causes K loss?
Aldosterone, black licorice, hypomagnesemia, polyuria increase renal excretion of K+
Calcium range and daily intake
8.5-11mg/L. 1000mg/day. 1200mg if >50yr old
Calcium natural sources
Dairy, broccoli, oranges, canned fish. (Vitamin D improves absorption, undigested fat prevents absorption.)
Calcium albumin relationship
Low albumin leads to low calcium
Calcium loss factors
Thiazide diuretics decrease renal excretion of Ca. Chronic diarrhea & undigested fat increase excretion of Ca. Balance controlled by PTH, calcitonin and vitamin D.
Calcium functions
Influences excitability of nerve and muscle cells; necessary for muscle contraction, bone health, activation of clotting mechanism.
Magnesium range and daily intake
1.3-2.1mg/dl. 320-420mg/day. (we start replacing at 1.8)
Mg natural sources
Dark green leafy veggies, whole grains, milk, nuts (Undigested fat prevents absorption.)
Mg loss factors
High blood ethanol increases & oliguria decreases renal excretion of Mg. Chronic diarrhea & undigested fat increase fecal excretion.
Mg functions
Sedative effect on neuromuscular junctions (inhibits acetylcholine and diminishes muscle excitability); nerve conduction, DNA synthesis
Phosphate range and daily intake
2.4-4.4mg/dl. 20-40mmol/day
Phosphate natural sources
Milk, poultry, fish, beans, nuts, processed foods. Aluminum antacids prevent absorption. Need vitamin D for intestinal absorption
Phosphate loss factors
Oliguria decreases renal excretion of PO. PTH stimulates renal tubes to excrete phosphorous. Kidneys are major route of phosphate excretion.
Phosphate functions
Necessary for production of ATP (energy source for cellular metabolism). Muscle, RBCs, bone, teeth, CNS function. PTH stimulates secretion of phosphorus via kidneys
Isotonic fluids
NS, D5W, LR,
Hypotonic fluids
1/4, 1/2 NS
Hypertonic fluids
3,5% NS, D5+electrolytes, D10 and higher,
ECV deficit s/sx
Sudden weight loss, orthostatic hypotension, tachycardia, thready pulse, flat or collapsing neck veins when supine, slow vein filling, oliguria, concentrated urine, dry mucous membranes, skin turgor, absence of sweat/tears, tongue furrows, thirst, restlessness, confusion, hypotension, cold, clammy skin, hypovolemic shock.
Labs: Elevated Hct, BUN > 25 mg, urine specific gravity > 1.030.
ECV excess s/sx
Sudden weight gain, edema in dependent areas, full neck veins when upright, crackles, pulmonary edema, bounding pulse.
Labs: BUN
Hypernatremia s/sx
Extreme thirst, dry/flushed skin, postural hypotension, fever, restlessness, oliguria, N/V, confusion, agitation, coma, seizures.
Nx: Treat underlying cause, gradual water replacement (5DW), diuretics.
Labs: Na > 145 mEq & serum osmolality > 295 mOsm/kg, urine specific gravity 1.030, alkalosis
