updated potassium disorders

Question 1

potassium is the main ion for which fluid compartment ?

Answer 1

intracellular fluid compartment

Question 2

what are potassiiumm sparing diureticcs ?

Answer 2

drugs that cause diuresis without causing potassium loss in thee urine liike spironolactone

Question 3

wheere does aldosterone mainly have its effect ?

Answer 3

distal tubules

Question 4

what is the clinical presentation of hypokalemia ?

Answer 4

affection includes :
muscles : weakness, paralysis in severe hypokalemia
heart : arrhythmias , ECG flat T wave and prominent U wave
kidney : nephrogenic diabetes insipidus

Question 5

what are the causes of hypokalemia ?

Answer 5

renal loss
intracellular shift with the use of insulin or due to alkalosis
GIT loss

Question 6

what are the renal loss causes of hypokalemia ?

Answer 6

1. loop diuretics
2. increased adrenal gland activity:
   conn’s syndrome
   cushing syndrome
   renal artery stenosis
3. decreased tubular potassium reabsorption

Question 7

what diseases cause decreased tubular potassium reabsorption ?

Answer 7

bartter syndrome
gitelman syndrome

Question 8

what is bartter syndrome ?

Answer 8

defect in the Na-K-Cl transporter in the ascending loop of henlle

Question 9

what is gitelman syndrome ?

Answer 9

defect in the Na-cl cotransporter in the distal tubules

Question 10

what are the indications for oral potassium replacement ?

Answer 10

mild to moderate hypokalemia more than 2.5 mEq/L

Question 11

what are the indications for IV potasssium infusion ?

Answer 11

severe hypokalemia
symptomatic hypokalemia
less than 2.5 mEq/L

Question 12

what are the precautions that must be taken when using IV potassium infusion ?

Answer 12

• IV maximum rate is 10-20 mEq/h
• Use isotonic 0.9% saline
• Do not use dextrose containing fluids, as they
  increase insulin release and lower potassium

Question 13

what is the clinical presentation of hyperkalemia ?

Answer 13

weakness in the muscles
ECG changes : peaked T wave
abnormal cardiac conduction ( heart block )

Question 14

what are the causes off hyperkalemia ?

Answer 14

decreased urinary excretion
extracellular shift

Question 15

what are the causes of decreased urinary excretion that may lead to hyperkalemia ?

Answer 15

1- drugs - potassium sparing diuretics
ACE and ARBs
2- decreased renal gland activity : Addison’s
3- renal failure

Question 16

what are the causes of extracellular shift of potassium causing hyperkalemia ?

Answer 16

insulin deficiency
digoxin
beta blockers
cell lysis as with rhabdomyolysis and tumor lysis syndrome
acidosis

Question 17

what is pseudohyperkalemia ?

Answer 17

potassium movement out of the cells while in the test tube causes pseudohyperkalemia

Question 18

if a patient with hyperkalemia presents with ECG changes what is the treatment ? ( cardio protective measures)

Answer 18

attach a 12 lead ECG and administer calcium gluconate

Question 19

what is the last line of treatment if all measuress failed in controlling hyperkalemia ?

Answer 19

dialysis

Question 20

what are the methods that increase potassium loss and decrease body potassium levels ?

Answer 20

loop diuretics
cation exchange
dialysis

Question 21

what are the drugs used in treatment to induce intracellular shift of potassium ?

Answer 21

sodium bicarb
insulin and dextrose
beta 2 agonist

Question 22

what are the drugs that cause hyperkalemia ?

Answer 22

ACE and ARB
sprionolactone (potassium sparing )
NSAIDs
high dose trimethoprim
digoxin toxicity
high dose beta 2 blockers