Potassium

HyperkalemiaHypokalemiaSerum K more than 5.5mEq/LSerum K less than 3.5mEq/LDefinition

(1 )Transcellular shiftAcidosis, Tumour lysis, blood transfusion and drugs.

(2 )Renal impairmentGFR drop below 10ml/min.

(1 )Transcellular shiftB2 agonist, Hypothermia, Alkalosis, Insulin.

(2 )Renal K lossDiuretics, Mg depletion, NG drainage

(3 )Extrarenal K lossDiarrhea

Etiology

(1 )ECG abnormalitiesPeaked T wave.1st degree heart block.Complete heart block.Ventricular fibrillation.

Muscle weakness, inversion T wave, Long QT interval.

Manifestations

(1 )Antagonize cardiac effects(1 )Estimate K deficit.(2 )Give20 mEq of KCL to 100ml of

isotonic saline over 1h through a large central vein.

Management

Hypokalemia

Definitions

Hypokalemia is a serum potassium concentration below 3.5 mEq/L Severe hypokalemia is a serum potassium concentration below 2.5 mEq/L

Causes

(1 )Transcellular shift: B2 agonist, alkalosis, hypothermia, insulin. (2) Renal Potassium Loss: diuretic therapy, Magnesium depletion. (3) Extrarenal Potassium Loss: diarrhea

Clinical Manifestations

(1 )Diffuse muscle weakness. (2) Prominent U waves, inversion of T waves, prolongation of the QT interval. (3) Hypokalemia alone does not produce serious ventricular arrhythmias.

Management