Korean J Transplant.  2022 Nov;36(Supple 1):S391. 10.4285/ATW2022.F-5298.

Prevalence of hepatopulmonary shunt in agitated saline test and lung perfusion scan and predictive value of arterial oxygenation

• Lee S
• Lee KW
• Choi HH
• Kim J
• Hong Sy
• Choi Y
• Yi NJ
• Suh KS
• Lee J
• Kim JY

• KMID: 2535213
• DOI: http://doi.org/10.4285/ATW2022.F-5298

Abstract

Background
Hepatopulmonary syndrome is defined as arterial deoxygenation in cirrhotic patient with intrapulmonary vasodilatation evident in contrast-enhanced echocardiography or lung perfusion scan. Prevalence is reported to be around 5%–35%, and various threshold values defining arterial oxygenation have been reported from partial pressure of oxygen in the arterial blood of 70 or 80 mmHg. We aim to determine different HPS prevalence from echocardiography and lung perfusion scan and compared cut offs for arterial deoxygenation.
Methods
We analyzed 490 patients who had transthoracic contrast echocardiography tested for detection of pulmonary vaso-dilatation and blood gas analysis as preoperative work-up for liver transplantation.
Results
Two hundred and fifty-four patients showed positive on agitated saline test (51.8%) and of these 208 patients under-went lung perfusion scans showed positive hepatopulmonary shunt in nine (4.3%) patients. From ROC analysis the areas-un-der-the curve of PaO2 and A a gradient for predicting positive agitated saline test were 0.550 and 0.586, respectively. From ROC analysis the areas-under-the curve of PaO2 and A a gradient for predicting positive lung perfusion scan were 0.825 and 0.858. PaO2 and A-a gradient significantly correlated with hepatopulmonary shunt on lung perfusion scan at the cut offs of 76.3 mmHg and 36.25 mmHg, respectively. Positive predictive value was higher using A-a gradient (34.8 % vs. 19.5%).
Conclusions
In addition to contrast enhanced echocardiography, lung perfusion scan can increase the diagnostic rate of hepatopulmonary syndrome in cirrhotic patients undergoing liver transplantation.