Electrolytes Flashcards
what concentration do isotonic solutions have
- same solute concentration as blood plasma
- no fluid shifts
isotonic solution examples
- NS 0.9%, D5W, or lactate ringers solutions
- expect no shifts in fluids when giving to patients
what are isotonic fluids used for
- increase intravascular fluid volume (conditions with loss of volume)
- blood loss, dehydration (vomitting, diarrhea)
what would isotonic solution DSW used for
- fluid replacement when dehydrated
- used as keep-open or flush
- rehydrate when Na and Cl are concentrated
disadvantage of using DSW isotonic solutions
- electrolyte imbalance, interstitial and cellular edema
- do not use with head injuries
Normal saline uses
- replace loss of body fluid (bowel obstructions)
- increases plasma volume without changing Na concentration or serum osmolality
disadvantage using NS solutions
- dilutes RBC and plasma proteins
- lowers osmotic pressure (pulmonary edema)
- causes hypernatremia, hyperchloremic metabolic acidosis
ringers lactate is used for
- early stages of hemmoragic shock
- cheap
- balanced electrolytes to interstitial fluids
- does not increase serum Na or Cl
disadvantages with ringers lactate
- dilutes RBC and plasma proteins
- lowers osmotic pressure (pulmonary edema)
hypotonic solution
- have lower solute concentration than blood
- shifts into more concentrated solutions
hypotonic solution example
- 0.45% NS
- concentration of sodium in the solution is less than blood
who would you give a hypotonic
- cellular dehydration
in what situation would you have cellular dehydration
- loose fluid but not Na (hypernatremia)
- diabetes insipidus
- NG tube feeds - not getting enough fluids
- vommiting and diarrhea
negative effects using a hypotonic solution
- cerebral edema
- hypovolemia and hypotention
hypertonic solutions
- have higher solute concentration than the plasma
- fluid shifts from intracellular space into intravascular space
examples of hypertonic solutions
- 3% NS, 5% NS, 10% dextrose water
- have more solute concentrations than the plasma
what shifts occur when giving hypertonic solutions to patients
- fluid shifts from intracellular space to intravascular space
when would giving hypertonic solutions be helpful?
- hyponatremia
- brain injuries when you want to decrease swelling in the brain
what is hyponatremia
- low levels of sodium (less than 135)
main causes of low sodium imbalances (hyponatremia)
- excessive sodium loss
- excessive fluid input
- inadequate sodium intake
signs and symptoms of hyponatremia (115-120 sodium levels)
- sodium levels of 115-120 you will see: nausea, vomiting, headache, irritability, muscle twitching, tremors, weakness, lethargic
signs and symptoms of hyponatremia (less than 110 sodium levels)
- sodium levels less than 110: delirium, psychosis, seizures, coma
What happens when sodium levels are low? what major impact the body can this have? (hyponatremia)
- decreased extracellular osmolity
- fluid moves form intravascular space to intracellular space (cells swell)
- the brain is most affected
- seizures, coma, brain damage
hyponatremia can be classified into 3 categories
- hypovolemic hyponatremia
- hypervolemic hyponatremia
- isovolemic hypomatremia
what is the cause of hypovolemic hyponatremia
- sodium and water levels in intravascular space are low, sodium levels are lower
- vomiting, diarrhea, sweating, diuretic use
what is the cause of hypervolemic hyponatremia
- water in intravascular space dilutes sodium
- HF, liver failure, excessive administration of hypotonic solutions
what is the cause of isovolemic hyponatremia
- sodium levels appear to be low due to too much fluid in the body
- renal failure
- excessive release of ADH (water retention)
what will you manage mild hyponatremia (115-120)
- restrict fluid intake
- oral sodium supplements
- high sodium foods
- isotonic IV fluids secondary to hypovolemia
management for critical hyponatremia
- infusion of hypertonic solutions (3%, 5% saline)
- shift fluids out of extracellular spaces
- prevent fluid overload while on hypertonic solutions give lasix (close monitoring
what is hypernatremia and what can it lead to?
- sodium is high
- can cause seizures, coma, permanent brain damage
- fluid exists extracellular space
what causes hypernatremia?
water deficit:
- reduced water intake
- heatstroke
- athletes
- burns
- vomiting, diarrhea
- diabetes insipidus
- excessive diuresis
excessive sodium intake
what are 2 most significant clinical manifestations of hypernatremia?
- brain cells shrink (brain very sensitive to fluid changes)
- vascular rupture (fluid shift into intravascular space)
early signs of hypernatremia (7)
- restlessness
- agitation
- nausea
- vomiting
- low grade fever
- flushed skin
- intense thirst
later signs and symptoms of hypernatremia (7)
- weakness,
- lethargy
- confusion
- seizures
- twitching
- trmors
- coma
what would be present if hypernatremia is due to excessive sodium?
- hypervolemic
- elevated BP, bounding pulse, dyspnea
what would be present if hypernatremia is due to water deficit
- appear hypovolemic
- dry mucus membranes, oliguria, orthodox HTN
how will water deficit be managed to help relieve hypernatremia
- water intake increase gradually (dont want to overswell cells - water moves from high to low)
- if Pt can’t do oral intake then IV 5% dextrose (isotonic solution) to help return sodium levels then 0.45% hypotonic (low sodium - helps move water into cells)
how would we help decrease the chance with fluid overload when managing water deficit
- loop diuretics (lasix)
if the cause for hypernatremia is diabetes insidious how would this be managed?
- help ADH levels
- give vasopressin
- give IV fluids
- give thiazide diuretics
what is hypokalemia
- severe levels is less that 2.5
- can cause dysrhythmias, cardiac arrest, respiratory arrest
hypokalemia caused by not enough K in:
- inadequate K intake
- potassium deficient iv fluids
hypokalemia caused by too much K out:
- loss of GI fluids (vomiting, diarrhea, laxative use, diaphoresis)
- diuretic therapy
- cushing syndrome - increase diuresis
hypokalemia affecting skeletal muscles signs
- skeletal muscle weakness
- leg cramps
- decreased tendon reflexes
- respiratory muscles
GI/GU muscles affected signs during hypokalmeia
- nausea
- vomiting
- decreased bowel motility
- constipation
what happens to the heart during hypokalemia
- irregular HR
- palpitation
- ortho HTN
- inverted T waves, depressed ST segment
- ventricular dysrhythmias, bradycardia, tachycardia, cardiac arrest
how to manage hypokalemia
- high potassium diet and low sodium diet
- oral potassium supplements (KCl)
- IV potassium
- spironolactone diuretic
what is hyperkalemia
- greater than 5-7
- can cause dysrhythmias, cardiac arrest, respiratory arrest
how can you become hyperkalemic (9)
- increased K intake
- blood donations
- potassium sparing diuretic
- antibiotic
- chemo
- ace inhibitors and ARBs
- renal failure
- additions disease
- infection
signs and symptoms of hyperkalemia (8)
- muscle weakness
- decreased deep tendon reflexes
- nausea
- abd. cramping
- peaked T waves
- irregular HR
- ventricular fib.
- hypotension
how to manage hyperkalemia
- loop diuretics (lasix)
- K restrictions
- put on kayexalate
- IV insulin infusion with 10% dextrose solution -> glucose infusion as well
what is hypocloremia
- less than 98
- extracellular space low in Cl
- impacts levels of Na, K, and calcium
- bicarbonate increases when Cl is low = hypochloremic alkalosis
how does hypochloremic occur
- intake and output
- salt restricted diets
- GI disorders
- chloride follows sodium
- vomiting, diarrhea, burns, Addisons disease, NG suctioning, HF
signs and symptoms of hypochloremia
- same as hyponatremia and hypokalemia
how to manage hypochloremia
- salty foods
- NS IV
- give KCl
- treat diaphoresis
- treat vomiting
- treat GI issues
what is hyperchloremia
- greater than 108
- increased Cl in the extracellular space
- cause metabolic acidosis (decrease bicarbonate)
- associated with hypernatremia
signs and symptoms of hyperchloremia
- metabolic acidosis
- lethargy
- thirst
- weakness
- dehydration
- hypotension
- coma, decreased LOC, arrhythmia
manage hyperchloremia:
- give fluids
- IV sodium bicarbonate
all help decrease chloride levels
