(719) Cerebral Air Embolism Following Robotic Partial Nephrectomy

Introduction: Cerebral air embolism is a rarely occurring pathology within surgical critical care units. We present the case of a 47-year-old female following robotic partial nephrectomy complicated by pneumomediastinum and altered mental status diagnosed with cerebral air embolism on post-operative day 1.

Description: The patient is a 47-year-old female with a past medical history of renal mass, chronic headaches following traumatic brain injury, and anxiety who underwent robotic-assisted retroperitoneal right laparoscopic partial nephrectomy. Intraoperatively the patient developed acute hypoxia, hypocarbia, and ST-segment depression. The patient was stabilized and the surgical team completed the procedure. The patient was extubated in the ICU. Her physical exam was notable for thoracic subcutaneous emphysema and imaging significant for pneumomediastinum attributed to insufflation. Overnight the patient developed encephalopathy initially attributed to anesthetics. On POD 1, the patient's mental status further declined. She endorsed new-onset blindness and the inability to move her extremities. Exam was significant for dilated pupils and movement of all extremities to physical stimulation. CT head was positive for bilateral parenchymal hypodensities. MR brain demonstrated multifocal acute infarcts associated with leptomeningeal enhancement that can be visualized in the context of air embolism. Hyperbaric oxygen therapy was deferred, and heated high flow nasal cannula was initiated. The patient recovered neurologically and was deemed a candidate for inpatient rehabilitation.

Discussion: Cerebral air embolism remains a rare but potential etiology of encephalopathy following robotic operations requiring insufflation. While the mechanism of air entrainment into the vasculature was not defined, the patient's clinical presentation was suggestive of this rare diagnosis upon physical assessment and diagnostic imaging. There remains a paucity of literature regarding the recognition and diagnosis of this condition. There is no guideline-directed therapy for the management of cerebral air emboli, with case reports suggesting the implementation of hyperbaric oxygen therapy if evidence remains of air within the vasculature. It remains the role of the intensivist to recognize and diagnose this rare condition.