It is now clear that hepatopulmonary syndrome (HPS) may
occur and contribute significantly to gas exchange abnormalities
in the setting of other cardiopulmonary abnormalities.
Since there is no gold-standard diagnostic test for HPS,
diagnosis rests on documenting arterial oxygenation abnormalities
resulting from intrapulmonary vasodilatation in the
setting of liver disease. Retrospective studies suggest that
many patients with HPS develop progressive intrapulmonary
vasodilatation over time and that mortality is significant.
This case highlights the clinical value in investigating for
HPS and right-to-left shunts when confronted with a patient
presenting with unexplained hypoxia in combination with
platypnoea and/or orthodeoxia.