Fluid And electrolyte Imbalances Flashcards
What is the most common electrolyte abnormalities
Hyponatremia
Urine sodium
10-20
Serum osmolarity
Usually 2x Na
275-285
Urine sodium >20
Renal salt wasting
Problem with the kidneys
Urine sodium <10
Renal retention of sodium to compensate for extrarenal fluid losses
A problem other than the kidneys
Isotonic Hyponatremia
Pseudo hyponatremia, serum osmolality 284 to 295
Occurs with extreme hyper lipidemia or hypoproteinemia
Body water is normal and the patient is asymptomatic
Treatment: cut down fat
Hypotonic hyponatremia
Serum osmolality less than 280
State of body water excess deleting all body fluids clinical signs arise from water excess
Hypervolemic vS hypovolemic , if hypovolemic assess whether hyponatremia is due to extrarenal salt losses or Renal salt wasting
Hypovolemic with urine NA < 10
Causes
Dehydration, diarrhea, vomiting
Hypovolemic with urine NA >20
Low volume in kidneys cannot conserve sodium
Causes
Diuretics, ace inhibitors , mineralocorticoid deficiency
Hypervolemic, hypotonic Hyponatremia
Causes
Dementia states, congestive heart failure, liver disease, advanced renal failure
Tx: fluid restriction
Hypertonic hypo natremia
Serum osmolality greater than 290
Hyperglycemia usually from HHNK
Osmolality is high in the sodium is low
Management of hyponatremia
Treatment based on cause
Three underlying condition
If hypovolemic give normal saline IV
If urine sodium is greater than 20 treat the cause
If hypervolemic implement water restriction
If patient is symptomatic give normal saline with a loop diuretic
If CNS symptoms are present consider 3% normal saline with loop diuretics
Hypernatremia
Usually due to excess water loss always indicates hyper osmolality excessive sodium intake is rare
Severe Hypernatremia with hypovolemia treatment
Give normal saline IV until there is an acceptable blood pressure then switch to half normal saline
Hypernatremia with euvoleMia should be treated with
D5 W
Hypernatremia with hypervolemia should be treated with
Free water and loop diuretics , may need dialysis
Hypokalemia causes
Causes include chronic use of diuretics, gastrointestinal loss, excess renal loss and alkalisis
Elevated serum epinephrine and trauma patients make contribute to hypochonemia
Signs and symptoms of hypokalemia
Muscular weakness, fatigue and muscle cramps, constipation or alias due to smooth muscle involvement, if severe less than 2.5 May see flaccid paralysis, tetany, hyporeflexia, and rhabdomyolysis
Lab/Diagnostics of Hypokalemia
Decreased amplitude on EKG, broad T waves prominent U waves, PVCs, VTAch or V fib
Management of Hypokalemia
Oral replacement if greater than 2.5mEq and no EKG abnormalities
If less than 2.5 MEQ or severe signs and symptoms are present, make a 40me Q/L/hour Iv check every three hours in institute continuous EKG monitoring
Magnesium deficiency frequently impairs potassium fraction
Hyperkalemia causes
Causes include excess intake, renal failure, drugs, NSAIDs, hypo aldosteronism, and cell death.
Shifts of intracellular potassium to the extracellular space occur with acidosis
Potassium increases .7 mEq per liter with each 0.1 drop in potential hydrogen
Signs and symptoms of hyperkalemia
Weakness, flaccid paralysis, abdominal distention, diarrhea
Lab/diagnostics of hyperkalemia
50% of patients with potassium greater than 6.5 will not have EKG changes however tall, peaked T waves are a classic finding
Management of hyper kalemia
Exchange resins(Kayexalate)
If greater than 6.5 or cardiac toxicity or muscle paralysis is present consider:
Insulin 10 units with one amp D 50 for emergencies
