sodium and volume imbalances

Question 1

what is the primary determinant in ECF osmolality?

Answer 1

sodium

Question 2

what is the primary concern of hypernatremia?

Answer 2

cellular dehydration

Question 3

how does hypernatremia change osmolality?

Answer 3

make iso fluids into hyperosmotic solutions

Question 4

who is most at risk for hypernatremia?

Answer 4

cognitively impaired or elderly clients

Question 5

causes of hypernatremia due to water loss

Answer 5

sweating, sensible losses from high fever, sodium intake in excess of water intake, diabetes insipidus

Question 6

causes of hypernatremia due to sodium gain`

Answer 6

IV hypertonic NaCl, sodium bicarbonate, excessive isotonic NaCl

Question 7

what fluid shift occurs when IV hypertonic saline is administered?

Answer 7

fluid shift into the vessel (out of the cell)

Question 8

what fluid shift occurs when IV hypotonic saline is administered?

Answer 8

fluid shift into the cell (out of the vessel)

Question 9

clinical manifestations of hypernatremia

Answer 9

• intense thirst; dry, swollen tongue
• restlessness, agitation, twitching
• seizures/coma
• flushed skin
• weakness
• postural hypotension
• peripheral pulmonary edema
• weight loss or gain

Question 10

collaborative care of hypernatremia

Answer 10

prevent water loss - oral fluids, IV fluids (5% dextrose or hypotonic saline) - sodium levels must be reduced gradually to avoid cerebral edema from rapid fluid shift
sodium excess - dilute sodium concentration with salt free fluids, diuretics, restricted sodium intake, I&O

Question 11

what type of fluid shift occurs in hyponetremia

Answer 11

fluid shift from the vessel into the cells

Question 12

causes of hyponatremia due to water excess

Answer 12

hypotonic IV solutions, common in cats after surgery, trauma CHF, polydipsia

Question 13

causes of hyponatremia due to loss of sodium containing fluids

Answer 13

develops as body responds to fluid volume deficit: release ADH, retention of water lowers salt concentration
GI losses - N&V, diarrhea
Renal losses - diuretics, renal insufficiency
Skin losses - burns, wound drainage

Question 14

clinical manifestations of hyponatremia

Answer 14

• irritability, apprehension, weakness and confusion
• postural hypotension
• tachycardia
• rapid, thready pulse
• jugular venous filling
• N&V
• dry mucous membranes
• weight loss or gain
• tremors, muscle spasms
• headache

Question 15

what symptoms of hyponatremia manifest first?

Answer 15

CNS symptoms appear in the client first

Question 16

collaborative care for hyponatremia

Answer 16

water excess - fluid restriction, small amount of hypertonic saline (if seizures occur)
abnormal losses of sodium - fluid replacement

Question 17

what typically accompanies hypo and hypervolemia

Answer 17

at least one or more electrolyte imbalances - often associated with changes in sodium levels

Question 18

what are some causes of hypovolemia?

Answer 18

abnormal fluid losses (diarrhea, hemorrhage), decreased intake, or a plasma to interstitial fluid shift

Question 19

what are some causes of hypervolemia?

Answer 19

excessive intake of fluids, abnormal retention of fluids (CHF), or interstitial to plasma fluid shift

Question 20

collaborative care of hypovolemia

Answer 20

correct underlying cause - fluid and electrolyte replacement (balanced IV solutions [lactated ringers], isotonic sodium chloride, blood replacement)

Question 21

collaborative care of hypervolemia

Answer 21

removal of sodium and water without causing abnormal changes in electrolytes or osmolality of ECF (diuretics, fluid restriction, restriction of sodium intake

Question 22

nursing management of sodium and volume imbalances

Answer 22

• I&O
• CV changes
• Respiratory changes: fluid excess (pulmonary congestion and edema - SOD, irritability, cough, moist crackles); fluid deficit (increased rest rate, hypoxia)
• neuro changes (changes in LOC)
• daily weights
• skin assessment (turgor and mobility, dry MM, edema - promote venous re)

Question 23

an increase in 1 kg of body mass is equivalent to what?

Answer 23

1000 ml or 1 L