Serial Pulse Oximetry in Hepatopulmonary Syndrome

Background/Aim The natural history of hepatopulmonary syndrome (HPS) is poorly characterized and how hypoxemia develops and progresses over time is unclear. We evaluated oxygenation over time in advanced liver disease patients with and without HPS using serial pulse oximetry. Methods Data from a prospective cohort of patients evaluated for liver transplantation were analyzed. All patients with significant cardiopulmonary disease were excluded and patients with and without HPS were compared. Arterial oxygen saturation measurements with pulse oximetry (SpO2) were recorded serially from initial evaluation until transplantation or last clinic visit on record. Patients with SpO2 measurements at C2 visits were included. Results A total of 22 HPS patients were compared to 32 non-HPS patients (18 with intrapulmonary vasodilation on contrast echocardiography, CE) over a mean duration of 20 months and 4 SpO2 measurements. HPS patients had lower SpO2 at baseline (96.8 vs. 98.4%, P = 0.02) and at end of follow-up (95.8 vs. 98.2%, P = 0.02), and were more likely to have a C2% reduction (P = 0.04) and faster decline in SpO2 as compared to non-HPS patients (F = 2.2, P = 0.04). HPS patients with lower SpO2 and/or PO2 at baseline appeared more likely to worsen over time. There was no difference in SpO2 over time between the 2 non-HPS subgroups (- or ?CE). Conclusions HPS patients have a significant decline in SpO2 over time compared to non-HPS patients, and therefore, pulse oximetry may be useful for monitoring cirrhotics for development or worsening of HPS. Presence of intrapulmonary vasodilation in the absence of hypoxemia does not appear to affect SpO2 over time.