High-Flow Oxygen Therapy to Support Inpatient Pulmonary Rehabilitation During Very Severe Hepatopulmonary Syndrome Recovery Post Liver Transplant: A Case Report.

This case study reports the novel use of inpatient pulmonary rehabilitation (PR) with near-maximal high-flow oxygen therapy in a patient recovering from very severe hepatopulmonary syndrome (HPS) following liver transplantation. HPS is a rare condition where advanced liver disease alters lung microvasculature through intrapulmonary vascular dilatation (IPVD) and angiogenesis. Platypnoea-orthodeoxia (postural dyspnoea with concurrent blood oxygen desaturation) is characteristic of HPS due to redirection of blood flow to the basal lung where IPVDs are more prominent, secondary to gravity. Currently, the only definitive treatment is liver transplantation, which allows normalization of oxygenation over an extended period, typically within 1 year. Pulmonary rehabilitation is an effective intervention for improving dyspnoea, health-related quality of life (HRQoL), and exercise capacity in people with chronic respiratory disease. Despite this, little is known of the effect PR has on individuals recovering from HPS post liver transplant. The aim is to describe an inpatient PR program for a patient recovering from HPS. This case study describes a 27-year-old male with "very severe" HPS who undertook inpatient PR 5 months posttransplant. The patient completed an 8-week program of twice-weekly PR supported by high-flow oxygen therapy (fraction of inspired oxygen of 90%). He performed aerobic and resistance exercises for the upper and lower limbs in recumbent, seated, and standing positions. The patient improved in exercise capacity on the 1-min sit-to-stand test (+4 repetitions), lower limb strength on the 5-repetition sit-to-stand test (-3.4 s) and in HRQoL outcomes assessed. Following rehabilitation, the patient still had a high burden of respiratory symptoms and required continuous high-flow oxygen therapy. This case study demonstrates that inpatient PR, modified for HPS-associated platypnoea-orthodeoxia and supported by high-flow oxygen therapy, is safe and effective and therefore feasible for other HPS patients.