fluid/acid-base HYPO K (07-25) (1)

Question 1

Uptd. Causes 5 groups?

Answer 1

Decr. intake
Incr. translocation into cells
Incr. urinary losses
inc. GI losses
Other: sweat, dialysis, plasmapheresis

Question 2

Shift into cells. Cases?

Answer 2

Insulin

B2 agonists

elevated serum pH (alkalosis)

hypokalemic periodic paralysis

incr. blood cell production (nes incr. K uptake for new cells synthesis)

Hypothermia

Chloroquine, celsium, barium, antipsychotic intoxication

Question 3

B2 agonists how cause K into cell?

Answer 3

STRESS (eg MI, acohol withdrawal, endogenus epinehprine release) OR BETA AGONISTS

by increasing the activities of the Na-K-ATPase pump and the Na-K-2Cl (NKCC1) cotransporter and possibly by increasing the release of insulin.

Question 4

Urinary losses. 2 mechanisms?

Answer 4

Increased mineralocorticoid activity – Aldosterone –> reabs. Na and secrete K.

Increased distal delivery of sodium and water

Question 5

Urinary losses. causes?

Answer 5

Diuretics - increase distal delivery and, via the induction of volume depletion, activate RAAS.

Primary mineralcorticoid excess

polyuria

loss of gastric secretions - incr. in sodium bicarbonate delivery to collecting duct

nonreabsorbable anions

RTA type I and II

Hypomagnesemia

Amphotericin B, gentamicin

low calorie diet

Bartter and Gitelman syndromes (FA)

DKA

Question 6

GI losses? 4

Answer 6

• Vomiting
• Diarrhea
• Nasogastric tube drainage
• Laxative abuse

Question 7

GI losses. Upper. Mechanism?

Answer 7

The concentration of potassium in gastric secretions is only 5 to 10 mEq/L; thus, potassium depletion in this setting is primarily due to increased urinary losses.

Question 8

Gi losses. Lower. mechanism?

Answer 8

K in lower intestinal losses is relatively high (20 to 50 mEq/L) in most cases.
In addition, hypokalemia due to lower GI tract losses (usually from diarrhea) are typically associated with bicarbonate wasting and hyperchloremic metabolic acidosis rather than the metabolic alkalosis observed with upper gastrointestinal losses.

Question 9

Symptoms?

Answer 9

Usually asymtomatic.
If symptoms - fatigue, muscle weakness, cramps, ileus, hypoflexia, paresthesias, rhabdomyolysis, ascending paralysis

Question 10

FA. Hypokalemia usually why?

Answer 10

RENAL +/- GI losses

Question 11

FA. If not responding to treatment, what is the reason?

Answer 11

Check magnesium level

Question 12

FA. Digitalis. What to monitor?

Answer 12

Need monitor K.

Hypokalemia sensitizes the heart to digitalis toxicity, because K and digitalis compete for the same sites on the Na/K pump.

Question 13

Hypokalemia.
Muscle symptoms?

Answer 13

Usually when severe hypoK.
Same patter as in hyperK.
Ascending weakness: legs –> upper body.

Can be cramps, rhabdomyolysis, myoglobinuria.

Resp. muscle weakness –> res. failure
GI muscles –> ileus

Question 14

Hypokalemia.
Arrhythmias?

Answer 14

premature atrial complex and premature ventricular beats, sinus bradycardia, paroxysmal atrial or junctional tachycardia, atrioventricular block, atrial fibrillation, and ventricular tachycardia or fibrillation.

Question 15

Hypokalemia.
ECG changes?

Answer 15

U waves which occur at the end of the T wave;

flat T wave

ST depression

Question 16

FA. Treatment.
1st?

Answer 16

treat undelying cause

Question 17

HypoK.

Prolonged hypoK can cause structural and functional changes in kidney,

Answer 17

.

Question 18

FA. Treatment.
2nd?

Answer 18

Oral or i/v K.

Question 19

FA. Treatment.
What electrolyte?

Answer 19

Treat hypomagnesemia

Question 20

Treatment. Rate of K i/v?

Answer 20

10 to 20 mEq/hour. Rates above 20 mEq/hour are highly irritating to peripheral veins.

Question 21

Dose with infusion?

Answer 21

1000 ml - 4,5g.
100-200ml - 750mg

Question 22

i/v K adverse?

Answer 22

Pain and phlebitis

Question 23

severe hypoK?

Answer 23

serum potassium less than 2.5 to 3.0 mEq/L

or

symptomatic (arrhythmias, marked muscle weakness, or rhabdomyolysis).

Question 24

how many grams inc 1mmol?

Answer 24

1-1,5 mmol/l = 3 g

Question 25

mild to moderate decr.? range and treatmen?

Answer 25

3.0 to 3.4 mEq/L.

who do not have ongoing urinary potassium losses, we suggest initial oral administration of 10 to 20 mEq of potassium given two to four times per day (20 to 80 mEq/day)

Question 26

also can give K-sparing diuretics

Answer 26

.

Question 27

FA. countinuous rate of K as additive is preffered than I/v bolus (can cause hyperK).

boluses preserved for symptomatic and ECG changes

Answer 27

.