Fluid And Electrolytes Flashcards
Clinical manifestations of slow hypernatremia versus rapid hypernatremia?
Management?
Volume depletion versus confusion, lethargy, coma
D5 1/2NS
versus
D5 1/3NS or even D5W
Estimated water loss based on hypernatremia?
Every 3 mEq/L of hypernatremia represents 1 L of water lost
Rule of thumb for treating hypernatremia?
Rapidly correct the hypovolemia, but slowly correct the tonicity
Major causes of hyponatremia? Management?
- Inappropriate ADH secretion (post-Op water intoxication, tumors)
- Loss of large amounts of isotonic fluids (from G.I. tract)
#If rapid, hypertonic saline. #If slow, water restriction #If from G.I. fluid loss – isotonic fluid
Why does G.I. fluid loss cause hyponatremia?
- Loss of isotonic fluid
2. Retention of water to maintain correct volume
Hypokalemia – typical causes? Management?
- G.I. tract losses
- Urine losses (direct, aldosterone)
10 mEq per hour
Hyperkalemia – typical causes?
Management options - ultimate? Fastest? Others?
- Kidney cannot excrete potassium (renal failure, aldosterone antagonist)
- Dumping of potassium into blood (acidosis, crush injuries, necrosis)
#Ultimate therapy – hemodialysis #Fastest - Ca #Push potassium into cells – dextrose and insulin, B-2 agonists, Bicarb #Suck/neutralize potassium out of G.I. tract – (NG suction, Kayexalate)
Metabolic acidosis – general causes?
#Production of fixed acids (DKA, low flow states) #Loss of buffers (blocks of bicarb) #Inability to eliminate acids (renal failure)
Metabolic acidosis – in addition to fixing base deficit, be prepared to replace?
Potassium
Metabolic alkalosis – most cases will correct with administration of? Rarely need?
KCl – 5-10 mEq per hour
Ammonium chloride or .1 N HCL