Hepatopulmonary Syndrome (HPS) is a rare abnormality of the lung which is caused by liver disease. Although not all patients with liver disease get this lung abnormality, patients who do have it can become short of breath and have low oxygen levels.
Hepatopulmonary syndrome is a pulmonary complication of liver disease which affects 5-32% of cirrhotics1. It is defined by a triad of features:
- Liver dysfunction or portal hypertension
- Intrapulmonary vascular dilatations (IPVDs)
- Abnormal oxygenation (on arterial blood gas: an alveolar-arterial oxygen gradient ≥ 15-20 mmHg or PaO2 < 80 mmHg4 )
The pathophysiology of HPS remains unclear and it is unknown why some patients with liver disease develop IPVDs while others do not. Hypoxemia in HPS is primarily due to diffusion limitation and ventilation-perfusion mismatch caused by the presence of IPVDs1.
Dyspnea at rest or upon exertion is the predominant symptom of HPS. This usually develops after years of liver disease, but can also be seen as the presenting complaint in patients with previously undiagnosed liver disease2. A more specific finding is that of platypnea-orthodeoxia – breathlessness and worsening hypoxemia experienced in the upright position that is improved in the supine position5. Patients may also exhibit cyanosis and/or digital clubbing.
Liver transplantation (LT) is the only known effective therapy for HPS, with significant improvement in oxygenation observed in the majority of survivors within one year of transplantation3. Long-term ambulatory oxygen therapy is the mainstay of supportive therapy for HPS, and there may also be a role for pre-and post-operative pulmonary rehabilitation.
We are always accepting referrals from physicians for diagnosis and follow up of HPS patients.
Appointments are usually available within 3-4 weeks once the referral is received.
Patient video explaining intrapulmonary vascular dilatations (IPVDs)
Video Transcript: In a healthy person, red blood cells pass through the small blood vessels in the lungs, picking up oxygen from the air inside the lungs. This oxygen is then able to travel to supply the rest of the body. In hepatopulmonary syndrome the small blood vessels in the lungs become dilated or wider and the oxygen is no longer able to reach all the red blood cells within the vessel. This means that less oxygen is absorbed from the lungs.
When to think about HPS
HPS is not limited to patients with severe liver dysfunction; in fact, many patients with moderate to severe HPS have comparatively well preserved hepatic function¹. While the majority of patients initially present with features of their liver disease, a minority will present with pulmonary complaints, as noted above.
As such, any patient presenting with features of liver disease or portal hypertension who complains of progressive dyspnea (reported in 95% of HPS patients) with abnormal pulse oximetry (SaO2 ≤ 97% ) should be referred for further pulmonary evaluation6.
A more specific complaint is that of platypnea – breathlessness experienced in the upright position which is improved in the supine position. This in turn correlates to the objective finding of orthodeoxia, a drop of ≥ 4mmHg in PaO2 or ≥ 5% in saturation when moving from the supine to the standing position, occurring in as many as 88% of HPS patients5.
Other clinical manifestations of HPS include:
- Cyanosis (positive predictive value of 100%)2
- Digital clubbing (positive predictive value of 78%)
- Spider angiomata (positive predictive value of 21%)
It is important to note that chest x-ray and thoracic CT scanning are often unremarkable in HPS; a lack of radiographic abnormalities is not sufficient evidence to rule out HPS.
After pulmonary evaluation, any patient with a PaO2 < 80 mmHg and/or alveolar-arterial oxygen gradient (AaDO2) > 15 mmHg that cannot be fully explained by other diagnoses should be referred for a diagnostic workup for possible HPS4.
- Rodriguez-Roisin R, Krowka MJ: Hepatopulmonary syndrome–a liver-induced lung vascular disorder. New England Journal of Medicine 2008;358(22):2378-2387.
- Fallon MB, Abrams GA: Pulmonary dysfunction in chronic liver disease. Hepatology 2000;32(4 Pt 1):859-865.
- Iyer VN, Swanson KL, Cartin-Ceba R, Dierkhising RA, Rosen CB, Heimbach JK, et al. Hepatopulmonary syndrome: favorable outcomes in the MELD exception era. Hepatology 2013;57(6):2427-35.
- Rodriguez-Roisin R, Krowka MJ, Herve P, Fallon MB, ERS Task Force Pulmonary-Hepatic Vascular Disorders (PHD) Scientific Committee. Pulmonary-Hepatic vascular Disorders (PHD). [Review] [281 refs]. European Respiratory Journal 2004;24(5):861-880.
- Krowka MJ, Dickson ER, Cortese DA: Hepatopulmonary syndrome. Clinical observations and lack of therapeutic response to somatostatin analogue. Chest 1993;104(2):515-521.
- Abrams GA, Sanders MK, Fallon MB: Utility of pulse oximetry in the detection of arterial hypoxemia in liver transplant candidates. Liver Transplantation 2002;8(4):391-396.
- Krowka, M. J., Fallon, M. B., Kawut, S. M., Fuhrmann, V., Heimbach, J. K., Ramsay, M. A., … & Sokol, R. J. (2016). International Liver Transplant Society practice guidelines: diagnosis and management of hepatopulmonary syndrome and portopulmonary hypertension. Transplantation, 100(7), 1440-1452.