Liver transplantation and pulmonary gas exchanges in hypoxemic children.

Hypoxemia in cirrhotic patients is well documented. One of the possible causes of this association seems to be the presence of functional intrapulmonary shunts. The extent of the ventilation/perfusion ratio (VA/Q) abnormalities and their regression after orthotopic liver transplantation has been previously studied in adults by the multiple inert gas elimination technique. We report here a similar study in three children where the hypoxemia was the main indication for early liver grafting, although the liver function was still preserved at that time. Their hypoxemia was almost exclusively caused by a right to left shunt (VA/Q = 0) with a minimal amount of poorly ventilated but well perfused areas (Low VA/Q). This association may explain the poor response of the arterial oxygen pressure to an increased inspired oxygen concentration. Despite these very large VA/Q mismatches, the children underwent successful liver transplantations, resulting in a regression of the intrapulmonary shunt, as demonstrated by multiple inert gas elimination technique, and compatible with a normal life.