Transcript HYPOKALEMIA

HYPOKALEMIA
Definition
• serum potassium concentration < 3.5 mEq/L
Etiology
• total body potassium deficit
▫ Poor intake
▫ Excessive renal & GI loss
• serum potassium is shifted into the intracellular
compartment
• drug
Drug induce hypo K
Category & Clinical presentation
State
Serum K level
Clinical
presenttation
asymptomatic
mild
3-3.5 mEq/L
moderate
2.5-3 mEq/L
cramping, weakness,
malaise, and
myalgias
severe
< 2.5 mEq/L
ECG changes
arrhythmias
ECG changes: ST-segment depression or flattening,T-wave inversion, and U-wave
elevation
Treatment
• K supplement  3 salt (Chloride, phosphate,
carbonate)
• PO  mild to moderate (should be divided into
3-4 doses to minimize the developement of GI
side effects)
• IV  severe (K < 2.5 mEq/L)
 exhibiting signs symptoms of
hypokalemia
 patients unable to tolerate oral therapy
KCl oral
• 10% KCl elixir (20 mEq/15 ml)
• Ped KCl 2% (4 mEq/15ml)
10% KCl elixir
serum K
60 ml
0.3-0.8
120 ml
0.4-1.6
180 ml
0.6-2.4
KCl IV infusion
• NaCl
• D5W  advoided
• 10 to 20 mEq of potassium is diluted in 100 mL
0.9% NaCl
• administered through a peripheral vein over 1
hour
• Mutiple dose: can be repeated as needed until
the serum potassium concentration normalizes
(equilibium time 30 min)
KCl IV infusion (Conc.)
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Severe K depletion
KCl 300 to 400 mEq/day
dilute 40 to 60 mEq in 1,000 mL 0.45% NaCl
Rate of infusion: not exceeding 40 mEq/h
• Central intravenous line into a large vein
(e.g., superior vena cava)
Alternative therapy
Potassium-sparing diuretics
• Spironolactone : 25-mg, 50-mg, and 100-mg
tablets
▫ Start 25 to 50 mg daily  titrated to a maximum
dose of 400 mg/day.
▫ side effects: hyperkalemia, gynecomastia, breast
tenderness, and impotence
Alternative therapy
• Triamterene: 50-mg and 100-mg capsules
▫ Start 50 mg twice daily titrated to 100 mg twice
daily
▫ side effects: hyperkalemia, sodium depletion, and
metabolic acidosis
• Amiloride: 5-mg tablet
▫ Start 5 mg daily; however, 10 mg can be given in
those with severe hypokalemia
Alternative therapy
• Generally, concomitant use of potassium
supplementation with potassium-sparing
diuretics is not necessary.
• There is a significant risk of hyperkalemia
during combination therapy, especially in
patients with underlying renal insufficiency or
diabetes mellitus.
The end