K+ is the major determinant what r/t cell excitability
RMP
Ca++ is the major determinant of what r/t cell excitability
threshold potential
Normal Ionic balance:
what is the normal rmp? and what controls it
-90Â
K+
Normal Ionic balance:
what is the normal threshold? and what controls itÂ
-60Â
Ca++
point to the RMP
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Normal Ionic balance:
clearify
Muscle rmp is -90
Nerve is -70
just so i dont get confused
Normal Ionic balance:
point to the Threshold line

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Normal Ionic balance:
what one is HYPOkalemia

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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
- Moves away from threshold
Normal Ionic balance:
Point to HYPERkalemia
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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
- MORE excitable
Normal Ionic balance:
what the hell can cause D? and what is going on?
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- the RMP has past the threshold
- Cardioplegia solutionÂ
- Hyperkalemia
- Na+ channel snaps open
- causes absolut refractory period b/c Na+ channels can't fireÂ
- K+ levles = 15-40 mEq
- causes absolut refractory period b/c Na+ channels can't fireÂ
 Normal Ionic balance:
point to Hyper calcemia
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Normal Ionic balance:
explain how you know it is hypercalemia and what it all means.

- Threshold is hypopolarzed
- moves closer to 0Â
- ​​Decreased excitability
- bigger gap b/t rmp and threshold
- More stimulus is needed to elict a response
- moves closer to 0Â
- bigger gap b/t rmp and threshold
Normal Ionic balance:
what the hell if F showing?
Â

- hyperkalemia treated with Ca++
- the RMP is hypopolarized (hyperkalemia)
- the threshold is increased to decrease the excitability
- threshold increased
- threshold increased
Normal Ionic balance:
what is G showing explain how you know  and what it all means.
Â

- 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
- threshold is decreased
- smaller gap between RMP and Threshold
can s/s of hypocalcemia be elicited when the pt is hyperventilated?Â
yes, hyperventilation can cause resp alkolosis. ionzied Ca++ decreasesÂ
therapies and mechanisms for treating HYPERkalemia:
what is the fastest treatment, but does not correct the hyperkalemia
Give Ca++
therapies and mechanisms for treating HYPERkalemia:
why administer HCO3-
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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
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therapies and mechanisms for treating HYPERkalemia:
what does hyperventilation do?
Â
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
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for each 10mmHg decrease in PaCO2 serum K+ decreaseshow much?
0.5 mEq/L
therapies and mechanisms for treating HYPERkalemia:
what does giving insulin-glucose do?
Â
insulin stimulates Na+K+ pump, drives K+ into the cells
Insulin also opens glucose channels
Glucose is administered along with insulin to prevent hypogylcemia
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therapies and mechanisms for treating HYPERkalemia:
what do Beta-2 agonist do?
Â
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stimulates Na+K+ pump, drives K+ into the cells
insulin stimulates Na+K+ pump, drives K+ into the cells
2 additional treatments
kayexalate
Dialysis