Profound Asymptomatic Hyponatremia Associated With Anuric Acute Kidney Injury: Successful Controlled Correction Using Short Intermittent Hemodialysis

Profound hyponatremia (<110 mmol/L) represents a critical electrolyte disturbance associated with significant neurological risk, particularly when rapid correction precipitates osmotic demyelination syndrome. Therapeutic management becomes especially complex when severe hyponatremia coexists with anuric acute kidney injury (AKI) requiring urgent renal replacement therapy, as intermittent hemodialysis may induce abrupt sodium shifts. We describe the case of a 66-year-old hypertensive woman receiving hydrochlorothiazide and perindopril who presented 10 days after cataract surgery with severe anuric AKI, profound asymptomatic hyponatremia (104 mmol/L), hyperkalemia (6.6 mmol/L), elevated creatinine (143 mg/L), and urea (2.6 g/L). Despite the severity of biochemical abnormalities, the patient remained conscious, hemodynamically stable, and neurologically intact, with normal thyroid and adrenal function. Given the urgency of treating hyperkalemia and uremia while avoiding overcorrection of sodium, a carefully individualized intermittent hemodialysis strategy was implemented using ultra-short initial sessions, controlled blood flow (220 mL/min), gradual dialysate sodium adjustment, and concomitant dextrose infusion. This approach enabled progressive correction of serum sodium to 126 mmol/L over four consecutive sessions without exceeding recommended safety thresholds and without neurological complications. This case highlights that meticulously tailored short-duration intermittent hemodialysis can achieve safe sodium correction while addressing life-threatening metabolic indications, suggesting a potential alternative when continuous renal replacement therapy is unavailable.