Chloride and Potassium - Ex 5

Question 1

Hypochloremia (corrected) - Diff 2

Answer 1

1. Loss of Cl
   - high gastric vomiting –> loss of high chloride content fluid
   - Loop or thiazide diuretics: excessive chloride loss from kidneys
2. Chronic respiratory acidosis
   - chloride is lost through kidney (NH4Cl-)

Question 2

Hyperchloremia

Answer 2

Rare - not going into it

Question 3

Potassium metabolism

Answer 3

• Principal cation of the ICF
• Specific roles
• membrane potential
• cardiac rate and rhythm
• renal sodium handling (e.g. K out, Na in)
• Acid-base balance

***K is super important!! Needs to stay within strict reference interval

Question 4

General disorders of Potassium

Answer 4

*Not as affected by water

• Main effects
  1. Redistribution
  2. Inc or dec intake
  3. Inc or dec excretion

Question 5

Acidosis

Answer 5

K+ goes from ICF to ECF

*not always predictable

Question 6

Alkalosis

Answer 6

K+ goes from ECF to ICF

*not always predictable

Question 7

Insulin & K+

Answer 7

Insulin helps K go into cells

DM –> insulin deficiency –> animal can become hyperkalemic

Question 8

Hypokalemia - Redistributional 3

Answer 8

1. Alkalosis
   - metabolic or respiratory
2. Insulin
   - if you give insulin you risk making animal hypokalemic
3. Excitement
   - epinephrine

Question 9

Hypokalemia - Absolute 5

Answer 9

1. Decreased intake
2. Anorexia
   - seen in ruminants
3. Diarrhea (MOST COMMON)
   - increased load of Na to colon
   - Na is absorbed –> K is excreted
4. Vomiting
5. Renal loss
   - Na avidity in dehydration, K lost in cation exchange
   - Loop diuretics: inc tubular flow
   - cats with CRF

Question 10

Hypokalemia - large animals 2

Answer 10

Saliva is high in K

Equine sweat is relatively high in K

Question 11

Hypokalemia - CS

Answer 11

Generalized muscle weakness
- “Plantigrade” stance

Cardiac arrhythmias

Question 12

Hyperkalemia - Redistributional 2

Answer 12

1. Metabolic acidosis**
   - protons enter the cells
   - K exits to maintain intracellular electroneutrality
2. Insulin deficiency: DM

Question 13

Pseudohyperkalemia

Answer 13

1. Hemolysis
   - in vitro if serum is left on clot
   - Horses(!!), pigs, some dogs (Akitas)
2. Thrombocytosis (rare)

Question 14

Hyperkalemia - Absolute 3 main

Answer 14

1. Metabolic acidosis
   - redistribution first, then dec secretion
2. Renal failure***
   - terminal chronic
   - severe acute (anuric or oliguric)
3. Uroabdomen***
   - urine is high in K –> leaks into abdomen –> equilibrates
4. Hypoadrenocorticism***
   - Aldosterone is responsible for excretion of K and absorption of Na –> when aldosterone is missing this is reversed

Question 15

Hyperkalemia - Uroabdomen

Answer 15

• Urine is high in K
• K diffuses through mesothelium

Result: hyperkalemia, hyponatremia, hypochloremia

Question 16

Hyperkalemia - Hypoadrenocorticism

Answer 16

• Addison’s Dz
• deficiency of mineralocorticoids
• mineralocorticoids stimulate K excretion in exchange for Na retention

Result: hyperkalemia, hyponatremia, hypochloremia