Paradoxical carbon dioxide embolism during laparoscopic hepatectomy without intracardiac shunt: A case report

Laparoscopic hepatectomy has recently become popular because it results in less bleeding than open hepatectomy. However, CO₂ embolism occurs more frequently. Most CO₂ embolisms during laparoscopic surgery are self-resolving and non-symptomatic; however, severe CO₂ embolism may cause hypotension, cyanosis, arrhythmia, and cardiovascular collapse. In particular, paradoxical CO₂ embolisms are highly likely to cause neurological deficits. We report a case of paradoxical CO₂ embolism found on transesophageal echocardiography (TEE) during laparoscopic hepatectomy, although the patient had no intracardiac shunt.

A 71-year-old man was admitted for laparoscopic left hemihepatectomy. During left hepatic vein ligation, the inferior vena cava was accidentally torn. We observed a sudden drop in oxygen saturation to 85%, decrease in systolic blood pressure (SBP) below 90 mmHg, and reduction in end-tidal CO₂ to 24 mmHg. A "mill-wheel" murmur was auscultated over the precordium. The fraction of inspired oxygen was increased to 100% with 5 cmH₂O of positive end-expiratory pressure (PEEP) and hyperventilation was maintained. Norepinephrine infusion was increased to maintain SBP above 90 mmHg. A TEE probe was inserted, revealing gas bubbles in the right side of the heart, left atrium, left ventricle, and ascending aorta. The surgeon reduced the pneumoperitoneum pressure from 17 to 14 mmHg and repaired the damaged vessel laparoscopically. Thereafter, the patient's hemodynamic status stabilized. The patient was transferred to the intensive care unit, recovering well without complications.

TEE monitoring is important to quickly determine the presence and extent of embolism in patients undergoing laparoscopic hepatectomy.