Massive intra-abdominal irrigation fluid extravasation causing respiratory compromise and compressive hepatopathy during biportal lumbar foraminal endoscopic surgery: a case report.

Introduction: Biportal endoscopic spinal surgery is increasingly adopted as a minimally invasive technique with favorable clinical outcomes. Although neurologic complications, such as incidental durotomy and neural injury, are well-documented, serious visceral complications related to irrigation fluid extravasation are rarely reported. We describe a case of massive intra-abdominal irrigation fluid leakage following biportal extraforaminal lumbar discectomy, which resulted in acute respiratory failure and transient hepatic dysfunction. Methods: A 59-year-old male who developed sudden abdominal distension and dyspnea immediately after biportal endoscopic extraforaminal discectomy at L4-5 was evaluated. Clinical examination, computed tomography (CT), arterial blood gas analysis, and serial laboratory testing were performed. Radiologic attenuation values were assessed to differentiate simple fluid from hemorrhage. Percutaneous catheter drainage and diuretic therapy were administered for decompression and supportive management. Results: Physical examination revealed marked abdominal enlargement and tachypnea. CT demonstrated extensive retroperitoneal-to-intraperitoneal fluid accumulation with inferior vena cava compression and bilateral pleural effusions. Arterial blood gas analysis showed severe respiratory acidosis (pH 7.1). Laboratory findings indicated acute hepatic injury with markedly elevated alanine transaminases (peak ALT 1129 IU/L). Hounsfield unit measurements suggested simple irrigation fluid rather than hemorrhage. A large volume of intra-abdominal fluid was evacuated through percutaneous drainage and diuretic therapy, resulting in rapid clinical improvement. Liver enzyme levels normalized within 2 weeks, and the patient was discharged without residual symptoms. Conclusion: Massive irrigation fluid extravasation during biportal extraforaminal endoscopic lumbar surgery can precipitate abdominal compartment syndrome-spectrum physiology, leading to respiratory compromise and reversible compressive hepatopathy. Careful intraoperative monitoring of irrigation inflow-outflow balance and early recognition of intra-abdominal hypertension are essential to prevent life-threatening organ dysfunction.