WHAT ARE THE PRINCIPLES IN THE TREATMENT OF HYPOKALEMIA? Question # 6

GOALS OF THERAPY Raise plasma Na concentration by restricting water intake and promoting water loss Correct underlying disorder

Treatment Strategies Mild asymptomatic hyponatremia – no tx Asymptomatic hyponatremia + ECF volume contraction – Na repletion: isotonic saline Severe symptomatic hyponatremia (< mmol/L) – altered mental status, seizures – Give hypertonic saline

Treatment Strategies Hyponatremia in edematous states – Restrict Na and water intake – Correction of hypokalemia – Promotion of water loss in excess of Na (loop diuretics)

WHAT IS THE COMPLICATION OF THE RAPID CORRECTION OF HYPONATREMIA? Question # 7

Osmotic Demyelination Syndrome Central pontine myelinolysis Correction greater than 12 mmol of sodium per liter per day – occurs as a consequence of a rapid rise in serum tonicity following treatment in individuals with chronic, severe hyponatremia who have made intracellular adaptations to the prevailing hypotonicity neurologic complications (seen 1-3 days after correction): – Acute flaccid paralysis, dysarthria, dysphagia Osmotic demyelination syndrome following correction of hyponatremia RH Sterns, JE Riggs, and SS Schochet

Other Studies central pontine myelinolysis (0.5%), post- correction seizures (1.0%), intellectual impairment (2.2%), tremor (0.5%), paresthesia (0.5%), and striatal syndrome (0.5%) Neurological sequelae were associated with faster rates of correction, and correction of chronic severe hyponatraemia should be <10 mmol/l in 24 h. Severe hyponatraemia: complications and treatment S.J. ELLIS Department of Neurology, University of Keele North Staffordshire Royal Infirmary, Stoke-on-Trent, UK