Related Experiment Video
Updated: May 17, 2026

Intra-cardiac Side-Firing Light Catheter for Monitoring Cellular Metabolism using Transmural Absorbance Spectroscopy of Perfused Mammalian Hearts
Published on: May 12, 2019
A case of unexplained cyanosis
Prashilla Soma1, Shiraz Ellemdin
1Department of Physiology, University of Pretoria, Pretoria, South Africa. prashilla.soma@up.ac.za
Abstract:
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.
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