Kidney Week 2025 Annual Meeting-Don't Let It Go to Your Head: Hyponatremia and the Brain

Video Transcription

Video Summary

This ASN session on hyponatremia and the brain honored Dr. Nicholas Madias and featured talks spanning cellular mechanisms, clinical management, cognitive effects, and the long-running controversy over “safe” correction rates.<br /><br />Fabrice Gankam Kendi reviewed brain adaptation to hyponatremia: acute swelling triggers “regulatory volume decrease” via rapid efflux of electrolytes (KCl) followed by slower loss of organic osmolytes (e.g., myo-inositol, taurine, glutamate). Adaptation is largely complete by ~48 hours. Rapid correction of chronic hyponatremia can cause osmotic demyelination syndrome (ODS), linked to electrolyte “overshoot” and delayed osmolyte reaccumulation. Newer data emphasize early astrocyte injury, protein aggregation, ER stress, disrupted astrocyte–oligodendrocyte coupling, and subsequent demyelination; urea appears protective in animals.<br /><br />Amy Yao discussed hyponatremic encephalopathy: acute cases (post-op, MDMA, exercise) risk cerebral edema; chronic cases more often cause subtle neurologic dysfunction. Guidelines favor hypertonic saline boluses to raise Na by ~4–6 mmol/L quickly, as small rises can reduce intracranial pressure and improve symptoms. Overcorrection risk is highest with hypovolemia, hypokalemia, low-solute intake, alcoholism, or polydipsia; prediction formulas often underestimate rises due to spontaneous water diuresis. DDAVP “clamp” strategies may reduce overcorrection.<br /><br />Juan Rondon reviewed evidence that mild chronic hyponatremia is not benign, associating it with attention deficits, gait impairment, and falls; mechanisms may involve glutamate dysregulation and impaired hippocampal plasticity. Trials of correction show mixed cognitive benefit.<br /><br />Richard Sterns traced the history of ODS/CPM, arguing ODS is uncommon overall but clinically meaningful in very low sodium (<115) with rapid correction; cerebral edema deaths are rare without coma. Debate persisted during Q&A over correction limits (often ~8 mmol/L/day in high-risk patients), the role of urea, dialysis challenges, and the need for better prospective data and hospital protocols.

Asset Subtitle

Moderator(s): Michael Moritz, Sagar Nigwekar

Presentation(s):

Mechanisms of Brain Cell Adaptation to Hyponatremia and Its Correction - Fabrice Gankam Kengne
Diagnosis and Management of Hyponatremic Encephalopathy - Amy Yau
Neurocognitive Deficits in Mild, Chronic Hyponatremia - Helbert Rondon Berrios
Osmotic Demyelination Syndrome: From Discovery to Denial - Richard Sterns

Meta Tag

Date 11/6/2025

Pathway 1 Fluid, Electrolyte, and Acid-Base Disorders

Session ID 504300

Keywords

hyponatremia

brain adaptation

regulatory volume decrease

organic osmolytes

myo-inositol

taurine

osmotic demyelination syndrome

central pontine myelinolysis

astrocyte injury

hypertonic saline bolus

hyponatremic encephalopathy

DDAVP clamp

overcorrection risk factors

mild chronic hyponatremia cognitive effects

safe sodium correction rate controversy