14 - Fluid And Electrolyte Flashcards
Gold standard for measuring urine concentration of electrolyte?
24 hr urine collection
- thought the fractional excretion from spot urine is more convenient
What does fractional excretion help determine? (Results)
The kidney’s response to a specific electrolyte
- Low fractional excretion - renal absorption
- High fractional excretion - renal wasting
Disorders of sodium concentration are a result of?
Water balance
Disorders of ECF volume are a result of?
Disturbances in sodium balance
What does serum sodium indicate?
What does it not reflect?
Indicates - relative amounts of sodium and water
Does not reflect ECF volume status
Hyponatremia is (level)?
Serum sodium <135 mEq/L
Clinical findings of hyponatremia?
Nausea Malaise HA Lethargy Disorientation
Respiratory arrest
Seizure
Coma
Brainstem herniation
hyponatrema needs to be carefully corrected to avoid?
Central pontine myelinolysis
Hyponatremic pts serum osmolality?
Can be
low - isotonic hyponatremia
normal- hypotonic hyponatremia
high - hypertonic hyponatremia
Chart on slid 11 if you want
Hypernatremia is (level)?
Serum sodium >145mEq/L
Hypernatremia always has?
Hyperosmolality
But may still be hypo, eu, or hypervolemic
Urine osmolality is used to measure?
The kidneys ability to conserve water
Distinguish between renal and non-renal losses
Tx for hypernatremia?
Fluid replacement
Disorders of sodium balance include?
Hypervolemia - volume overload
- abnormal na retention
Hypovolemia - decreased ECF volume
- Na excretion > Na input
How is a pts acid-base status measured?
Combination of
- arterial pH
- PCO2
- Plasma bicarbonate (HCO3)
Chart of results on slide 16