Inhaled nitric oxide as a salvage therapy for refractory hypoxemia in the post-transplantation period of hepatopulmonary syndrome: An explorative report of three cases

Abstract

Liver transplantation (LT) is the only effective treatment for hepatopulmonary syndrome (HPS). Moreover, perioperative refractory hypoxemia (pRH) is a prevalent life-threatening condition and has extremely limited treatment options. Here, we report three patients with HPS who experienced pRH after LT and were consecutively treated with different salvage therapies, ephedrine inhalation, intravenous use of methylene blue with nitric oxide (NO) inhalation, and NO inhalation alone. The results showed that unresolved severe hypoxia may induce fatal morbidity such as early biliary leakage and acute kidney injury. Early initiation of NO inhalation, rather than ephedrine, can significantly improve oxygenation in patients with pRH and may help prevent hypoxia-related complications. Therefore, based on the response to these exploratory salvage treatments, we further demonstrate the unique ventilation-perfusion mismatch pathophysiology in specific lung regions during pRH in HPS. We propose that early inhalation of NO is an important treatment option to rescue severe hypoxia in patients with HPS during the perioperative period of LT.

Keywords

Hepatopulmonary syndrome / Liver transplantation / Hypoxia / Nitric oxide (NO) / Vasodilators / Ventilation-perfusion mismatch

Data availability statement

The data presented in the case report are available from the corresponding authors upon reasonable request.

Authors’ contributions

Haijin Lyu, Xiaomeng Yi and Yunshan Zou contributed equally to this work and should be considered co-first authors. Haijin Lyu: Writing e review & editing, Writing e original draft, Validation, Investigation, Conceptualization. Xiaomeng Yi: Investigation, Data curation. Yunshan Zou: Resources, Investigation. Pinglan Lu: Methodology, Investigation. Lijuan Li: Methodology, Investigation. Jianrong Liu: Methodology, Investigation. Senbiao Chen: Meth-odology, Investigation. Xuxia Wei: Writing e review & editing, Writing e original draft, Supervision. Yang Yang: Supervision, Re-sources, Data curation, Conceptualization. Huimin Yi: Writing e review & editing, Writing e original draft, Validation, Resources, Conceptualization.

Declaration of competing interest

Yang Yang is an executive associate editor for Liver Research and was not involved in the editorial review or the decision to publish this article. All authors declare that there are no competing interests.

Acknowledgements

This study was supported by the National Natural Science Foundation of China (No. 82270690 and 82200732), the Natural Science Foundation of Guangdong Province (No.2021A1515012382, 2022A1515011919 and 2022A1515012519). These funds only used for providing the supply of nitric oxide.

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