Pulmonary hypertension due to unknown causes in liver resection.

A 16-year-old male underwent transcatheter arterial embolization against a large hepatic tumor, and was subsequently scheduled for removal of the tumor. Sudden hypotension and tachycardia were observed on removal of the tumor. Massive bleeding or obstruction of the inferior vena cava was expected to develop, but this did not occur because of simultaneous pulmonary hypertension (PH). The development of acute PH due to pulmonary vasoconstriction was suspected. Milrinone and prostaglandin E1 were effective. The same type of PH was again observed during manipulation of the residual portion of the liver. The acute PH was reproducible each time the liver was manipulated, which could suggest that this series of PH was specifically related to the hepatic lesion. A necrotic hepatic lesion might play an important role in disturbing the pulmonary circulation and causing the development of acute PH.