Fluid and electrolyte balance and disturbances Flashcards Preview

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Flashcards in Fluid and electrolyte balance and disturbances Deck (24)
1

K+ is the major determinant what r/t cell excitability

RMP

2

Ca++ is the major determinant of what r/t cell excitability

threshold potential

3

Normal Ionic balance:

what is the normal rmp? and what controls it

-90 

K+

4

Normal Ionic balance:

what is the normal threshold? and what controls it 

-60 

Ca++

5

point to the RMP

 

 

6

 

Normal Ionic balance:

clearify

Muscle rmp is -90

Nerve is -70

just so i dont get confused

7

Normal Ionic balance:

point to the Threshold line

 

8

Normal Ionic balance:

what one is HYPOkalemia

 

9

Normal Ionic balance:

explain how you know it is hypokalemia and what it all means.

  • RMP HYPERpolarized (more negative)
  • making it LESS excitable
    • Moves away from threshold
  • ​​More of a stimulus if needed to exert an action

10

Normal Ionic balance:

Point to HYPERkalemia

 

 

11

Normal Ionic balance:

explain how you know it is hyperkalemia and what it all means.

  • HYPOpolarized (less negative/closer to 0)
  • RMP moves closer the threshold
    • MORE excitable
  • Less of a stimulus is needed to evoke a response

12

Normal Ionic balance:

what the hell can cause D? and what is going on?

 

  • the RMP has past the threshold
  • Cardioplegia solution 
  • Hyperkalemia
  • Na+ channel snaps open
    • causes absolut refractory period b/c Na+ channels can't fire 
  • K+ levles = 15-40 mEq

13

 Normal Ionic balance:

point to Hyper calcemia

 

 

14

Normal Ionic balance:

explain how you know it is hypercalemia and what it all means.

  • Threshold is hypopolarzed
    • moves closer to 0 
  • ​​Decreased excitability
    • bigger gap b/t rmp and threshold
  • More stimulus is needed to elict a response

15

Normal Ionic balance:

what the hell if F showing?

 

  • hyperkalemia treated with Ca++
  • the RMP is hypopolarized (hyperkalemia)
  • the threshold is increased to decrease the excitability
    • threshold increased

16

Normal Ionic balance:

what is G showing explain how you know  and what it all means.

 

  • first a nerve cell b/c it says so and the RMP is at -70 (normal for nerve cell)
  • hypocalcemia is shown
    • threshold is decreased
  • Increased excitability
    • smaller gap between RMP and Threshold
  • Smaller stimulus will be neede to elict a response

17

can s/s of hypocalcemia be elicited when the pt is hyperventilated? 

yes, hyperventilation can cause resp alkolosis. ionzied Ca++ decreases 

18

therapies and mechanisms for treating HYPERkalemia:

what is the fastest treatment, but does not correct the hyperkalemia

Give Ca++

19

therapies and mechanisms for treating HYPERkalemia:

why administer HCO3-

 

H+ concentraions in the plasma decrease and metabolic alkolosis ensues.

H+ shifts out of cell to to buffer the alkolosis and in exchane K+ shfts into the cell

 

20

therapies and mechanisms for treating HYPERkalemia:

what does hyperventilation do?

 

H+ concentration in plasma decreases causing resp alkolosis occurs.

H+ shifts out of the cell to buffer the alkolosis and in exchange K+ shifts into the cell

 

21

for each 10mmHg decrease in PaCO2 serum K+ decreaseshow much?

0.5 mEq/L

22

therapies and mechanisms for treating HYPERkalemia:

what does giving insulin-glucose do?

 

insulin stimulates Na+K+ pump, drives K+ into the cells

Insulin also opens glucose channels

Glucose is administered along with insulin to prevent hypogylcemia

 

23

therapies and mechanisms for treating HYPERkalemia:

what do Beta-2 agonist do?

 

 

stimulates Na+K+ pump, drives K+ into the cells

24

insulin stimulates Na+K+ pump, drives K+ into the cells

2 additional treatments

kayexalate

Dialysis

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