Interstitial lung disease in patients with hepatopulmonary syndrome: a case series and new observations

Physiologic changes in the hepatopulmonary syndrome before and after liver transplant: A longitudinal and predictor analysis

BACKGROUND AND AIMS

Hepatopulmonary syndrome (HPS) is a common complication of liver disease defined by abnormal oxygenation and intrapulmonary vascular dilatation, treated with liver transplantation. Little is known about changes in HPS physiological parameters over time. We sought to describe baseline clinical and physiological characteristics in HPS and their relationships, temporal changes in physiological parameters before and after transplant, and predictors of changes in oxygenation.

APPROACH AND RESULTS

This was a retrospective cohort study in the Canadian HPS Program (n = 132). Rates of change after diagnosis were: -3.7 (-6.4, -0.96) mm Hg/year for partial pressure of arterial oxygen (PaO 2 ); -26 (-96, 44) m/year for 6-minute walk distance, and 3.3% (-6.6, -0.011) predicted/year for diffusion capacity. Noninvasive shunt of ≥ 20% predicted a slower PaO 2 decline by 0.88 (0.36, 1.4) mm Hg/month. We identified 2 PaO 2 deterioration classes-"very severe disease, slow decliners" (PaO 2 45.0 mm Hg; -1.0 mm Hg/year); and "moderate disease, steady decliners" (PaO 2 65.5 mm Hg; -2.5 mm Hg/year). PaO 2 increased by 6.5 (5.3, 7.7) mm Hg/month in the first year after transplant. The median time to normalization was 149 (116, 184) days. Posttransplant improvement in PaO 2 was 2.5 (0.1, 4.9) mm Hg/month faster for every 10 mm Hg greater pretransplant orthodeoxia.

CONCLUSIONS

We present a large and long longitudinal data analysis in HPS. In addition to rates of physiological decline and improvement before and after liver transplantation, we present novel predictors of PaO 2 decline and improvement rates. Our findings enhance our understanding of the natural history of HPS and provide pathophysiologic clues. Importantly, they may assist providers in prognostication and prioritization before and after transplant.

Outcomes of liver transplantation for hepatopulmonary syndrome in patients with concomitant respiratory disease

BACKGROUND & AIMS

Concomitant respiratory disease is a common finding in patients with hepatopulmonary syndrome (HPS). Among patients who underwent liver transplantation (LT) for HPS, we compared characteristics and outcome of patients with versus without concomitant respiratory disease.

METHODS

This single center retrospective observational study included patients with HPS who underwent LT between 1999 and 2020.

RESULTS

During the study period, 32 patients with HPS received a LT; nine (28%) with concomitant respiratory disease of whom one required a combined lung-liver transplantation. Patients with concomitant respiratory disease had higher PaCO2 (38 vs. 33 mm Hg, p = .031). The 30-day postoperative mortality was comparable, but the estimated cumulative probability of resolution of oxygen therapy after LT in HPS patients with versus those without concomitant respiratory disease was lower: 63% versus 91% at 12 months and 63% versus 100% at 18 months (HR 95% CI .140-.995, p = .040). In addition to the presence of concomitant respiratory disease (p = .040), history of smoking (p = .012), and high baseline 99mTcMAA shunt fraction (≥20%) (p = .050) were significantly associated with persistent need of oxygen therapy. The 5-year estimated cumulative probability of mortality in patients with concomitant respiratory disease was worse: 50% versus 23% (HR 95% CI .416-6.867, p = .463).

CONCLUSIONS

The presence of a concomitant respiratory disease did not increase the short-term postoperative mortality after LT in patients with HPS. However, it resulted in a longer need for oxygen therapy.

Anesthetic Management Using Low Fraction of Inspiratory Oxygen for Living Donor Liver Transplantation in a Patient With Hepatopulmonary Syndrome Complicated by Interstitial Pneumonia: A Case Report

BACKGROUND

Hepatopulmonary syndrome frequently complicates end-stage liver disease. It causes hypoxemia and requires oxygen administration. Additionally, interstitial pneumonia causes hypoxemia; however, it is known to be aggravated by high-concentration oxygen administration.

CASE PRESENTATION

A 71-year-old woman with hepatopulmonary syndrome and interstitial pneumonia underwent living donor liver transplantation, requiring conflicting management in terms of the inspiratory oxygen concentration. We achieved a low intraoperative fraction of inspiratory oxygen by increasing the cardiac output with intravenous catecholamines. As a result, the transplanted liver functioned well postoperatively, and the patient was discharged without exacerbation of the interstitial pneumonia.

CONCLUSION

We suggest that patients with hepatopulmonary syndrome complicated with interstitial pneumonia can undergo successful living donor liver transplantation without the use of high inspiratory oxygen concentration by using catecholamines to maintain a high mixed venous oxygen saturation.