Severe Hyponatremia Following Bilateral Pleural Catheter Placement in a Patient With Persistent Chylous Effusions.

Severe hyponatremia following indwelling pleural catheter (IPC) placement in patients with high-output chylous pleural effusions is a rare and infrequently reported complication. We report a case of a 52-year-old male with relapsed/refractory follicular lymphoma who developed severe hypo-osmolar hyponatremia one month after bilateral IPC placement for symptomatic chylous pleural effusions. High-volume drainage led to significant sodium loss, necessitating intensive care unit admission. Management with hypertonic saline, free water restriction, oral urea, and restricted IPC drainage, followed by thoracic duct embolization, improved serum sodium levels. This case highlights severe hyponatremia as a life-threatening consequence of high-output chylous effusions post IPC placement, emphasizing the need for careful electrolyte monitoring and restricted drainage to prevent severe electrolyte imbalances.