11. Spectrum and manifestation of hepato-pulmonary syndrome in 150 consecutive living related pediatric liver transplantation

Abstract

Background and Aims: Liver transplantation (LT) is challenging in hepatopulmonary syndrome (HPS). Pre-operative pO2 < 50 mmHg and MAAscan showing >20%shunting are believed to predict mortality post-LT. We aim to study profile, impact and outcome of HPS in pediatric-LT and to study use of inhaled nitric oxide (iNO) for refractory hypoxemia post-LT. Methods: Retrospective analysis. Age < 18 years. Study period: 2010-2016. HPS severity graded by 2 methods: pO2 room air (mild: >80 mmHg, moderate: 60–80 mmHg, severe: 50–60 mmHg, very severe <50 mmHg) and CE-ECHO (some shunt:few bubbles, significant shunt:dense opacification). Post- operative course and outcomes-were-studied. iNO used for refractory post-operative hypoxemia (sPO2 < 85% despite FiO2 100%) as per institutionally developed protocol. Results: Out of 150 patients studied, 23 had HPS. Mean age: 6.5 years. Biliary atresia was commonest underlying etiology (52.2%). By oxygenation criteria: Mild HPS:1 2 (52.2%), moderate-HPS:4 (17.3%), severe-HPS:1 (4.7%); very-severe HPS: 6 (26.1%). By CE-ECHO 12 (52.2%) had significant and 11 (47.8%) had some shunt. On MAAscan shunt-fraction ranged from 19.9–73%-it didn’t correlate with severity of pre-operative hypoxemia (p = 0.623), length of ICU stay (LOS) (p = 0.245) or hospital stay (p = 0.479). Patients with very severeHPS (n = 6) had higher LOS (p = 0.031) and duration of oxygen requirement (p = 0.001) compared to rest HPS patients. 4 of these 6 patients had-pO2 < 45 mmHg: this appeared to-be predictor of stormy post-operative course. One-out-of these 4 died-on 7th post-operative-day due-to intracranial-hemorrhage (ICH). Remaining 3 had refractory post-operative hypoxemia, prolonged-LOS and hospital stay. iNO was used in all 3 cases successfully (mean duration of iNO:26.3days). Incidence of hepatic artery thrombosis in HPS-group was 17.3% compared to 3.1% in non-HPS group (3.1%; p = 0.786). PV-thrombosis occurred in 1 (4.3%) in HPS group. ICH occurred in 2, both had pO2 < 45 mmHg. 1 died on POD7 and other recovered with intact neurological outcome. 1-year survival of HPS-group was 86.9% which was similar to nonHPS group (94.4%, p = 0.88). Conclusions: Pediatric LT in HPS, especially if severe is challenging. With good supportive care, outcomes of HPS and non-HPS patients are comparable. pO2 < 45 mm Hg, predicts a difficult post-operative course, rather than mortality. iNO is a successful strategy to overcome refractory postoperative hypoxemia. The authors have none to declare.