Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support
| (3) | Recent guidelines recommend use of bolus dosing over continuous infusion because |
|---|
of its ability to reach target sodium concentrations more quickly and concomitant
improvement in Glasgow Coma Scale scores (Clin J Am Soc Nephrol. 2024;19(1):129-
135).
| (b) | Prevention of overcorrection with preemptive administration of desmopressin (DDAVP |
|---|
| (1) | Desmopressin 1 to 2 ฮผg intravenously every 6โ8 hours + 3% NaCl continuous infusion |
|---|
to achieve a serum sodium increase of 6 mEq/L/day
| (2) | Not studied with hypertonic saline boluses (evaluated with continuous infusion only) |
|---|---|
| (3) | Only appropriate for severe hyponatremia and high risk of overcorrection |
| (4) | Avoid in patients with heart failure, hepatic cirrhosis, or volume overload |
| (c) | Treatment of overcorrection or relowering of serum sodium is recommended for patients |
at heightened risk of central pontine demyelination who have their sodium targets
overcorrected in the first 24 to 48 hours (Clin J Am Soc Nephrol. 2024;19(1):129-135).
| (1) | Desmopressin 1 to 4 ฮผg intravenously every 8 hours |
|---|---|
| (2) | Free water replacement of 3 mL/kg/hour either enterally with water or parenterally |
with 5% dextrose in water
| (3) | Recheck serum sodium every hour and continue until serum sodium goal is achieved |
|---|
ii.
Hypervolemic (ECF expanded) โ Fluid and sodium restriction, diuretic therapy as needed.
Consider conivaptan or tolvaptan if other therapies fail.
iii.
Hypovolemic (ECF reduced) and low urine sodium โ Give sodium and fluids for volume
expansion (treat etiologies if possible); reduce diuretic therapy. Sodium and fluid administration
can be done using 0.9% sodium chloride, lactated Ringer solution, or PlasmaLyte/Normosol
intravenously.
iv.
Euvolemic (ECF normal) โ Consider syndrome of inappropriate antidiuresis or secondary
adrenal insufficiency โ Fluid restriction first (if clinically appropriate); free water restriction
with use of 0.9% sodium chloride solution with or without diuretic therapy. Consider hypertonic
saline for acute or severe symptoms. Consider salt tablets, urea, or demeclocycline to maintain
normal serum sodium concentrations. Consider conivaptan or tolvaptan if other measures are
not effective.
Scenario
24-h correction (mEq/L)
48-h correction (mEq/L)
Normal risk (chronic hyponatremia
with Na โค 120 mEq/L)
Max: 10-12
Min: 4-8
Max: 18
Heighteneda risk
Max: 8
Min: 4-6
No major risk
Max: 8-12
aConventional water intake, thiazide diuretic use, hospital-acquired hyponatremia of known duration > 48 h.
Information from Clin J Am Soc Nephrol. 2024;19:129-135.