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Clinical Notice:OpiCalc is not a substitute for professional clinical judgment. Always verify dosages and guidelines.

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Sodium Correction

Serum Correction

Kats Hyperglycemia Model

Corrects for translational hyponatremia.

Tonicity Analyst

Enter measured sodium and glucose to execute translational water modeling.

Guidelines & Evidence

Verified

Last Review: 2026-07-17

When to Use

When to Use

Management of acute or chronic hyponatremia (Na < 135 mEq/L).
Symptomatic hyponatremia (seizures, altered mental status, coma).
Calculating the impact of various IV fluids on serum sodium levels.
Monitoring the safety of sodium correction to avoid over-correction.

Correction Goal

The goal is usually to alleviate symptoms, not to return to a "normal" range immediately. In chronic cases, a 4–6 mEq/L increase is often sufficient to stop severe symptoms.

How it Works

Adrogué-Madias Formula

Change in Serum Na = (Infusate Na - Serum Na) / (TBW + 1)

Total Body Water (TBW) Estimation

Non-elderly MenWeight × 0.6
Non-elderly WomenWeight × 0.5
Elderly MenWeight × 0.5
Elderly WomenWeight × 0.45

Common Infusate Na Content

3% Hypertonic Saline513 mEq/L
0.9% Normal Saline154 mEq/L
Lactated Ringer’s130 mEq/L
0.45% Half Normal Saline77 mEq/L
5% Dextrose (D5W)0 mEq/L

Clinical Pearls

The "Speed Limit"

Maximum Correction: 8–10 mEq/L in any 24-hour period (and < 18 mEq/L in 48 hours). For patients at high risk of ODS (alcoholism, malnutrition, liver disease), keep correction < 6–8 mEq/L/24h.

Osmotic Demyelination Syndrome (ODS)

Previously known as Central Pontine Myelinolysis. Rapid correction of chronic hyponatremia causes water to exit brain cells too quickly, leading to irreversible demyelination of the pons and other brain structures.

Key Gotchas

The formula does NOT account for urinary losses, which can cause Na to rise much faster than predicted (especially as ADH levels drop).
In volume-depleted patients, once fluids are replaced, ADH secretion shuts off, leading to a "water diuresis" that can dangerously accelerate Na correction.
Always use "Corrected Sodium" if the patient is significantly hyperglycemic.

Next Steps

Clinical Action Plan

01
Determine chronicity: If > 48h or unknown, treat as chronic.
02
For severe symptoms: Give 100 mL bolus of 3% saline; repeat up to 3x if symptoms persist.
03
Frequent Monitoring: Check Serum Na every 2–4 hours during active correction.
04
The "Desmopressin Clamp": In patients at very high risk for over-correction, some clinicians use DDAVP to prevent water diuresis and lock the Na rise at a predictable rate.
05
If over-correction occurs: Consider giving D5W or DDAVP to lower the sodium back toward the target limit.

Related Tools

Free Water Deficit (Hypernatremia)
Corrected Sodium for Hyperglycemia
FENa (Fractional Excretion of Sodium)

The Evidence

Primary Reference

Hyponatremia.

Adrogué HJ et al. • New England Journal of Medicine (NEJM). 2000;342(21):1581-9. Provides the clinical framework and formulas used globally for sodium management.

Consensus Guidelines

Diagnosis, evaluation, and treatment of hyponatremia: expert panel recommendations.

Verbalis JG et al. • American Journal of Medicine. 2013;Comprehensive US consensus on safe correction limits and management strategies.

Origins & History

The Madias Formula

Nicolaos Madias and Horacio Adrogué revolutionized electrolyte management by providing a simplified bedside equation. Before this, clinicians relied on complex "sodium deficit" equations that often failed to account for the impact of volume in the infusate.

Last Comprehensive Review: 2026-07-17

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Anion Gap
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Recent Journal Updates

JAMAJul 21, 2026
Correction to Primary Composite Outcome in a Trial of Transfusion Strategy

Clinical Context

We think this might be relevant to the clinical guidance for Sodium Correction Rate & Deficit.

FDA MedWatchJul 16, 2026
Convenience Kit Correction: Arrow International Issues Correction for Convenience Kits Containing Recalled Huons Lidocaine and Bupivacaine and Saline

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We think this might be relevant to the clinical guidance for Sodium Correction Rate & Deficit.

WHO NewsJul 15, 2026
Global childhood immunization coverage inches forward despite conflict and hesitancy – UNICEF, WHO

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