What is Dialysis Disequilibrium Syndrome, and which patients are at risk?

• A. Neurologic symptoms due to rapid solute shifts during dialysis; risk in new or high-solute-load patients
• B. Cardiogenic shock
• C. Anaphylaxis
• D. Hypoglycemia

Answer: (A)

Dialysis Disequilibrium Syndrome happens when rapid removal of uremic solutes during dialysis creates an osmotic gradient between the blood and brain, causing water to move into brain tissue and leading to cerebral edema with neurologic symptoms. It is most likely in patients who are new to dialysis or have a high solute load (very high BUN) because their blood solute levels drop quickly compared with brain solute levels, especially during the first dialysis sessions. Clinically, this can manifest as headache, nausea, vomiting, restlessness, confusion, seizures, or even coma as cerebral edema develops. Prevention focuses on starting dialysis more gently—slower or shorter sessions, lower blood/dialysate flow, and careful monitoring—so solute shifts occur gradually. If it happens, management centers on slowing or pausing dialysis and providing supportive care.

The other options describe entirely different problems: cardiogenic shock is a circulatory failure, anaphylaxis is an acute allergic reaction, and hypoglycemia is low blood glucose; none of these capture the rapid solute-shift mechanism and risk pattern of dialysis-related neurologic changes.