Hyperkalaemia & Hyporkalaemia

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Hyperkalaemia

1. Causes of Hyperkalaemia :
• Decreased or impaired potassium excretion – renal
failure, potassium -sparing diuretics, urinary obstruction,
sickle cell disease, Addison disease, and systemic lupus
erythematosus (SLE) .
• Additions of potassium into extracellular space -
potassium supplements (eg, PO/IV potassium, salt
substitutes), rhabdomyolysis, and hemolysis (eg, blood
transfusions, burns, tumor lysis) .
• Transmembrane shifts (ie, shifting potassium from the
intracellular to extracellular space) - acidosis and medication
effects (eg, acute digitalis toxicity, beta -blockers,
succinylcholine) .
• Factitious or pseudohyperkalemia - improper blood
collection (eg, ischemic blood draw from venipuncture
technique), laboratory error , leukocytosis, and
thrombocytosis .
2. ECG Changes :
• From reduction of P wave amplitude and prolongation of PR
interval to absence of P waves altogether.
• Increase of QRS duration.
• Increase of QT duration.
• Slowing of heart rate.
• T waves become tall and
spiked.
• Decreased R wave
amplitude .

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3.Principles of Treatment :

• Stabilise myocardium
• Move it into cells
• Increase elimination
1. Calcium Gluconate ... to counteract the effe ct of K on the heart.
2. D extrose + Insulin
3. Sodium Bicarbonate
4. Calcium Resonium
5. Salbutamol
6. Furosemide
7. haemodialysis

Hypokalemia

1. Causes of Hypokalemia :
I. Decreased intake
a. Starvation
b. Clay Ingestion
II. Redistribution into Cells
a. Acid -Base (Metabolic Alkalosis) .
b. Hormonal ( Insu lin, Beta agonist, Alpha ).
c. Anabolic State (folic acid) .
d. Other : Hypothermia, Pseudo hypokalemia.
III. Increased Loss
A. Non -renal loss
1. Gastrointestinal los s.
2. Integumentary Loss (sweat) .
B. Renal loss

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2.Signs & symptoms :

• Fatigue
• Myalgia
• Muscular weakness & paralysis
• Hyporeflexia
• Dyspnea
• Arrhythmia
• Predispose to digitalis toxicity
• Constipation
3. ECG changes :
• Due to delayed ventricular repolarization .
• Early changes : flattening or inversion of T wave, prominent U
wave, ST -segment depression, prolonged QU interval .
• Severe K+ depletion: prolonged PR interval, decreased
voltage and widening of QRS complex .

❖ Periodic limb hypokalaemic paralysis

Patient complain from recurrent attacks of paralysis……monitored
as inpatient due to risk of resp. failure .
Ppt. factors
1. heavy meals of CHO .
2. strenuous exercise .
3. standing from prolonged sitting .
4. awake from prolong sleeping .
Causes
1. idiopathic channelopathy.
1. thyroid disease .
2. other causes of recurrent hupokalaemia .

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Treatment

1. monitor of repiratory sys tem ……FVC .
2. correction of hypokalaemia by oral KCL…if patient sever
symptoms or cannot take orally, so infusion with fluid ???????
Mannitol infusion with KCL .
NO NO ….GW OR NORMAL SALINE ?????
3. treatment of the cause like thyroid problem .