II. Pathophysiology
- Lethal Cerebral edema from rapid Electrolyte correction
- Over-correction of Serum Sodium when <125 mEq/L
- Too rapid correction of Serum Sodium (>0.5 mEq/hour)
- Related to chronicity of Electrolyte disturbance
- Associated with rapid Sodium correction in chronic Hyponatremia (present >48 hours)
- Do not replace Serum Sodium more than 8 mEg/L per 24 hours
- Not associated with correction of acute Hyponatremia (esp. <24 hours)
- Severe symptomatic Hyponatremia (esp. <120 mEq/L) requires rapid Sodium replacement
- Associated with rapid Sodium correction in chronic Hyponatremia (present >48 hours)
III. Risk Factors
- Chronic Hyponatremia (present >48 hours)
- Serum Sodium <105 mEq/L
- Malnutrition
- Alcohol Use Disorder
- Hypokalemia
IV. Prevention
- In chronic Hyponatremia, do not correct Sodium >0.5 mEq/h or >8 mEq/day
- Some recommend limiting daily maximum correction to 6 mEq/day
- Recognize overcorrection early and manage aggressively
- Stop Sodium replacement
- Reverse Sodium overcorrection
- Replace urinary water loss with free water orally (or D5W at 3 ml/kg/hour) OR
- Desmopressin 2 to 4 mcg IV every 8 hours
V. References
- Le and Drogell (2015) Crit Dec Emerg Med 29(11): 13-19
- Miller (2023) Am Fam Physician 108(5): 476-86 [PubMed]