Fluid & Electrolyte Balance (PART 2)

Question 1

Effects of severe HYPERkalemia–TOO MUCH K+

1. Partial _______________ of cell membranes
2. Cardiac toxicity, ________ ___________ or asystole

Answer 1

depolarization

ventricular fibrillation

Question 2

Effects of severe HYPOkalemia–NOT ENOUGH K+

1. ________________ of cell membranes
2. Fatigue, muscle weakness
3. Hypoventilation
4. ________________ ventricular repolarization

Answer 2

Hyperpolarization

Delayed

Question 3

Control of Potassium Excretion

Excretion = Filtration - Reabsorption + Secretion

Answer 3

KNOW THIS EQUATION

Question 4

Renal tubular sites of potassium reabsorption and secretion.

1. In the______ distal tubule and collecting duct

Answer 4

late

Question 5

Control of Cortical Collecting Tubule (Principal Cells) K+ Secretion

1. Extracellular K+ concentration: increases
2. ____________: increases K+ secretion
3. _________ (volume) delivery: increases K+ secretion
4. Acid - base status:
   - ____________: decreases K+ secretion
   - ____________: increases K+ secretion

Answer 5

Aldosterone

Sodium

acidosis

alkalosis

Question 6

Increased serum K+ stimulates ____________ secretion

Answer 6

aldosterone

Question 7

INCREASE in Na+ Intake

= DECREASE in Aldosterone = INCREASE in K+
Secretion Cort. Collect.Ducts = Unchanged K+ Excretion

= INCREASE in GFR = INCREASE in Distal Tubular Flow Rate

= DECREASE in Proximal Tubular Na+ Reabsorption

Answer 7

know this pattern

Question 8

Acidosis Decreases Cell K+

but……

Alkalosis will:

1. INCREASE K+ in Cells
2. INCREASE K+ Secretion
3. INCREASE K+ Excretion
   with an end result = K+ DEPLETION

Answer 8

KNOW

Question 9

5 Causes of HYPERkalemia–HIGH K+ in the body.

1. __________ failure
2. Decreased distal ________ flow (heart failure, severe volume depletion, NSAID, etc)
3. ________ aldosterone or decreased effect of aldosterone
   - adrenal insufficiency
   - K+ sparing diuretics (spironolactone, eplerenone)
4. Metabolic acidosis (hyperkalemia is mild)
5. Diabetes (kidney disease, acidosis, insulin)

Answer 9

Renal

nephron

Decreased

Question 10

6 Causes of HYPOkalemia–body low in K+

1. Very low intake of K +
2. Metabolic alkalosis
3. Excess __________
4. GI loss of K+
   - diarrhea
5. Increased distal _________ flow/
   - salt wasting nephropathies
   - osmotic diuretics
   - loop diuretics
6. Excess ___________ or other mineralocorticoids

Answer 10

insulin

tubular

aldosterone

Question 11

Hormonal Response to Chronic Renal Disease - PTH

Chronic Renal Disease leads to INCREASE Nephron Loss

= INCREASE Plasma Phosphate 
= DECREASE Plasma Ca++
= \_\_\_\_\_\_\_\_\_\_\_\_\_ of PTH
= INCREASE of Bone Ca++ Release 
(osteoporosis - brittle bones)

Answer 11

INCREASE