Dr. Griffith Electorlytes and Liver Failure Flashcards
first step in assessing hyponatremia
volume status
hypovolemic
eu volemic
hypervolemic
hyponatremia - hypovelmic
renal vs. nonrenal
hyponatremia - hypovolemic - renal causes
Urine sodium > 20
nephropathies (recovery from ATN)
hyponatremia - hypovolemic - non renal causes
Urine sodium <10
vomiting, diarrhea, dehydration
hyponatremia - hypervolemic - renal causes
urine sodium > 20
ARF, nephrotic syndrome, CRF
hyponatremia - hypervolemic - non renal causes
urine sodium <10
CHF, cirrhosis (ascites)
hyponatremia - euvolemic causes
1) SIADH 2) Addison’s 3) drugs (thiazides) 4) hypothyroidism 5) psychogenic polydypsia 6) beer potamnia
SIADH diagnosis
one of exclusion
usually BUN <4
normal kidneys w/ low serum osmolity
low serum osm <280
urine should maximally dilute 50-100
when is 3% NS given?
rarely: coma, seizures
Addison’s disease
adrenal insuff
low sodium
high/normal K+
hypothyroidism - cause of hyponatremia
osmolality receptor reset
beer potamnia
solute poor beer
hypernatremia
dehydration or DI
check urine output (low - dehydration, high - DI) necrosis
hyperkalemia, think
1) pseudohyperkalemia
2) shifts
3) increased total body K
pseudohyperkalemia
lab artifact
- hemolysis
- WBC > 50,000
- platelets > 750,000
hyperkalemia - shifts
acidosis insulin deficiency (DKA) tissue necrosis
increased total body K+
1) increased intake (decreased excretion)
2) limited excretion
hyperkalemia - limited excretion
renal failure
type IV RTA
mineralocorticoid deficiency
drugs (ACEI, NSAIDs, heparin, etc)
hyperkalemia level
> 6
hyperkalemia EKG changes
non urgent - normal EKG
urgent - peaked T waves
emergent - widened QRS, loss of P wave, sine wave pattern
“spurious” cause of hyperkalemia
blood taken above IV
EKG changes in hyperkalemia per Mr. Sawaya
peaked T waves prolonged PR lose P waves widened QRS sine wave v tach/ v fib
hyperkalemia treatment
IV calcium IV dextrose + insulin IV sodium bicarb albuterol kayexelate dialysis limit K+ intake and observe correct underlying disorder