5.1 Potassium regulation

Question 1

locations of potassium reabsorption

Answer 1

-67% PCT
-asc limb via NKCC
-DCT

Question 2

locations of potassium secretion

Answer 2

-late DCT via ROMK
-CD via ROMK

Question 3

how do intercalated cells acts in acidosis?

Answer 3

(get rid of H+ from blood)
-H+ into CD
-K+ and HCO3- to blood

Question 4

how do intercalated cells acts in alkalosis

Answer 4

(get H+ into blood)
-H+ out of CD to blood
-HCO3- and K+ into CD

Question 5

ECG changes in hyperkaleamia

Answer 5

> 5.5 peaked T waves
6.5 PR prolonged, wide flat P waves
7 QRS prolonged
8 sine wave
9 PEA, systole, VF, severe bradychardia

Question 6

clinical features of hyperkalaemia

Answer 6

-asymptomiac maybe
-muscle weakness
-arryhthmias

Question 7

causes of hyperkalaemia

Answer 7

-lack of excretion
-released from cells
-excess administration

Question 8

emergency treatment of hyperkalaemia

Answer 8

EMERGENCY
-calcium glutinate to stabilise voltage gated calcium channels and myocardial membranes to prevent arrythmias
-insulin to drive K+ in cells to lower plasma conc
-glucose to avoid hypoglycaemia
-calcium resonium- removes K+ by increasing bowel excretion

Question 9

later treatment of hyperkalaemia

Answer 9

-low k+ diet
-stop causing medications
-furosemide for K+ loss in urine
-? dialysis

Question 10

where is K+ excreted from?

Answer 10

kidneys 80%
bowel 20%