NUR 112 Exam 1 Electrolytes K+

Question 1

K+ major cation found in ECF or ICF?

Answer 1

ICF

Question 2

Name cation needed for Na+ - K+ pump to work properly

Answer 2

Mg 2+

Question 3

In addition to neuromuscular and cardiac function list 3 things that K+ does in the body

Answer 3

1. regulates intracellular osmolality
2. promotes cell growth
3. Reg acid-base balance

Question 4

What organ excretes the majority of K+?

Answer 4

kidney

Question 5

K+ has an inverse relationship with which other cation? (1 is retained the other is excreted and vice versa)

Answer 5

Na+

Question 6

Will low blood volume cause K+ to be conserved or lost?

Answer 6

lost

Low BV = aldosterone production = inc. in reabsorption of Na+ = loss of K+

Question 7

List 2/3 things (drugs/situations) that cause K+ to shift from ECF to ICF

Answer 7

1. insulin
2. beta adrenergic stimulation (stimulates Na+ K+ ATP pump)
3. alkalosis (K+ exchanges with H+)

Question 8

List 2/3 things (drugs/situations) that cause K+ to shift from ICF to ECF

Answer 8

1. cell trauma (burns/crush injury/tumor lysis)
2. exercise
3. acidosis

Question 9

list 3 major causes of hyperkalemia

Answer 9

1. massive intake (salt substitute, K+ in drugs, IV fluid, hemolyzed RBC)
2. impaired excretion by kidneys.
3. shift of K+ from ICF to ECF

Question 10

list causes of impaired excretion of K+ by kidneys (4)

Answer 10

1. renal disease
2. K+ sparing diuretics
3. ACE inhibitors
4. adrenal insufficiency - not enough aldosterone = Na + excretion = K + retention

Question 11

At cellular level what does inc. in ECF K+ do?

Answer 11

increases cellular excitability

Question 12

s/s hyperkalemia in skeletal muscles

Answer 12

leg cramps
weakness
paralysis

Question 13

s/s hyperkalemia in smooth muscles

Answer 13

hyperactivity leading to: abdominal cramps

diarrhea

Question 14

s/s hyperkalemia in cardiac muscle

Answer 14

cardiac conduction disturbances:
cardiac depolarization is decreased
cardiac repolarization occurs more quickly
QRS complex widens
T waves Tall and peaked
v. fib
v. standstill

Question 15

general s/s hyperkalemia (4)

Answer 15

irritability
anxiety
parasthesias
irregular pulse

Question 16

List 5 main Tx for hyperkalemia

Answer 16

1. eliminate oral/parenteral K+ intake
2. eliminate K+ or dilute.
3. shift K+ from ECF to ICF
4. reverse (reduce) membrane excitability
5. hemodialysis (if pt. has renal failure)

Question 17

3 ways to eliminate/dilute K+ from/in body

Answer 17

1. diuretics
2. kayexalate (resin binds K+ in exchange for Na+ - then excreted in feces)
3. inc. fluids (inc. renal elimination)

Question 18

What is used to force K+ from ECF to ICF?

Answer 18

Insulin & glucose

Question 19

What is calcium gluconate used for in hyperkalemia?

Answer 19

to reverse (reduce) membrance excitability. Given in addition to diuretics, kayexalate, and insulin if pt. is experiencing dysrhythmias

Question 20

If pt. has renal failure and hyperkalemia what is Tx of choice?

Answer 20

hemodialysis