Sodium Disorders Flashcards
What is the normal value for Na+ in the body
135-145
T/F: Sodium is the major determinant of osmolarity in the body
True
Hyponatremia
low sodium level in the blood, most commonly an excess of water in relation to sodium
T/F: Hyponatremia can only occur in hypertonic states
False: Hyponatremia can occur in low, normal, or high tonicity states
What is moderate hyponatremia levels, severe
120, 110
What is an adaption the brain utilizes in hyponatremia
Brain Swelling
To prevent brain swelling in response to chronic hyponatremia how will the brain adapt , what are the consequences
Transport solutes extracellularly (NaCl, K, organic solutes), lowers brain osmolarity and induces water loss (hemorrhages)
What is a cause for high osmolarity hypertonic hyponatremia
Hyperglycemia, mannitol
What are causes of hypervolemic hypotonic hyponatremia
congestive heart failure, Liver failure, acute/chronic renal failure, nephrotic syndrome
What are causes of euvolemic hypotonic hyponatremia
Hypothyroidism, Addison’s disease, Syndrome of inappropriate ADH (SIADH)
Causes of SIADH
Central nervous system disorders (strokes, mass lesions, trauma acute psychosis), Malignancy (lung), medications
What are the causes of hypovolemic hypotonic hyponatremia
Renal loss (cerebral salt wasting, excessive diuresis, adrenal insufficiency), Non renal loss (bleeding, vomiting, diarrhea, burns/wounds, sweating)
In hypervolemic hypotonic hyponatremia what is the status of TBW, TBNa
high TBW, elevated TBNa
In euvolemic hypotonic hyponatremia what is the status of TBW, TBNa
elevated TBW, TBNa has little to no change
In hypovolemic hypotonic hyponatremia what is the status of TBW, TBNa
low TBW, Low TBNa
In treating hyponatremia what will be used
3%NaCl
In treating hyponatremia when is it appropriate to use 3%NaCl
Must have severe/ significant symptoms
What is the equation to calculate the change in serum Na+ per 1 liter of infusate
(infusate Na+- serum Na+)/(TBW+1)
What is the infusate Na+ of 3% NaCl
513
What is the infusate Na+ of 0.9% NaCl
154
What is the infusate Na+ of Lactated Ringers
130
What is the maximum correction rate for acute (< 48 hours) hyponatremia
1-2 mEq/L/hr
What is the maximum correction rate for chronic (> 48 hours) hyponatremia
0.5mEq/L/hr
What is the maximum correction rate for Na+ in serum for the entire day in patients who are hyponatremic
8mEq/L
What is the goal Na+ in serum after treatment for hyponatremia
125-130 or lower