Abstract Introduction Hepatopulmonary syndrome (HPS), present in up to one-third of patients with advanced liver disease, is characterized by liver dysfunction, intrapulmonary vascular dilatation, and impaired gas exchange. Liver transplantation is the only definitive cure; however, persistent post-transplant hypoxemia may occur, often requiring 100% supplemental oxygen. We describe the management of a patient with refractory hypoxia after liver transplantation and the novel therapeutic measures employed. Case Presentation A patient with decompensated cirrhosis secondary to alcohol use developed severe hypoxia, with home oxygen saturations of 80-90% on 3-6 L/min oxygen, minimal dyspnea, a positive late bubble study suggestive of intrapulmonary shunting, and normal pulmonary artery pressures—consistent with HPS. Following liver transplantation, his course was complicated by refractory hypoxia, with oxygen saturations on 6 L/min fluctuating between 80-90% supine and 70-80% upright. Workup including echocardiogram, contrast CT, and pulmonary angiogram with pressure measurements ruled out pulmonary embolism, arteriovenous malformations, and parenchymal lung disease. His condition was attributed to worsening post-transplant HPS. With escalating oxygen needs and desaturations to 30-40% on minimal exertion, he required heated high-flow nasal cannula support. A multidisciplinary team administered 100 mg of methylene blue, resulting in partial improvement. High-dose garlic therapy (4 g daily) was subsequently initiated, and within one week he was discharged on 10-15 L/min oxygen. Over three months, his oxygenation and dyspnea improved steadily, culminating in complete resolution of hypoxemia, at which point garlic was discontinued. Discussion In decompensated cirrhosis, elevated nitric oxide (NO) levels drive pulmonary vasodilatation, promoting HPS. After transplantation, NO levels decline, but vascular remodeling lags, causing preferential perfusion through persistently dilated vessels and ventilation-perfusion mismatch. Although gradual post-transplant improvement is reported, evidence for effective interventions in adults remains limited. Vasodilators were avoided to prevent worsening orthodeoxia; extracorporeal membrane oxygenation was deferred given uncertain recovery timing. Methylene blue, a NO scavenger and guanylate cyclase inhibitor, has demonstrated transient improvement in oxygenation in HPS. High-dose garlic has shown benefit via modulation of NO and endothelin-1 pathways, with longer-lasting effects. The transient methylene blue response supported subsequent garlic therapy, ultimately leading to complete resolution of severe hypoxemia. Conclusions This case highlights potential utility of methylene blue and high-dose garlic supplementation in refractory post-transplant hypoxemia due to HPS. Further research should clarify mechanisms, identify responders, and guide targeted therapy to improve outcomes in this high-risk population. This abstract is funded by: None
Cherabuddi et al. (Fri,) studied this question.