A case of ligation of the left pulmonary artery during total arch replacement for aortic arch aneurysm

: Pulmonary artery embolism is one of the most severe complications that can occur in the perioperative period. We report a case of left pulmonary artery obstruction during total arch replacement, which occurred during cardiopulmonary bypass (CPB) for severely invasive procedures. A 59-year-old male was anesthetized for total arch replacement using a double-lumen endobronchial tube (Bronco-Cath 39 F left) in the supine position. The surgery was performed under deep hypothermic circulatory arrest and CPB. When the CPB was finished and mechanical ventilation was started, PaCO2 was unusually elevated. Furthermore, end-tidal CO2 was decreased and no CO2 was expired from the left side of the double-lumen tube. Left pulmonary embolism was highly suspected and pulmonary artery angiography was performed. As the complete obstruction of the left pulmonary artery was demonstrated, pulmonary artery reconstruction was performed. The reason for the obstruction was the surgical ligation during CPB. The wall of the aneurysm was attached to the left pulmonary artery and when it was removed, the left pulmonary artery was injured. The systemic circulation remained stable, however, despite reports that pulmonary embolism was very dangerous and often caused the patient's death.