Hepatopulmonary Syndrome Diagnosis in the ICU: The Relevance of Bedside Contrast Saline Echocardiography

Abstract

Hepatopulmonary syndrome (HPS) is an underdiagnosed complication of chronic liver disease (CLD) characterised by the presence of hypoxaemia due to intrapulmonary vascular dilatations. We present two cases of HPS diagnosed during their stay in the ICU. Both patients had a medical history of alcoholic CLD with portal hypertension (PH). The first patient was transferred to the ICU for acute hypoxic respiratory failure (AHRF) due to decompensated cirrhosis with large-volume hydrothorax and diagnosis of acute-on-chronic liver failure (ACLF) grade 2. The presence of orthodeoxia, an alveolar-arterial oxygen gradient (O 2 A-a grad) of 27 mmHg and positive contrast saline echocardiography confirmed the HPS diagnosis. The second patient was transferred to our general ICU from the surgical ward where he was initially admitted with mild AHRF due to polytrauma conditioning left side rib fractures and a small contusion in the left inferior lobe. Upon ICU admission, he was diagnosed with septic shock (nosocomial pneumonia as the primary site of infection) and required invasive mechanical ventilation. During the initial period of his ICU stay, although an improvement in multiple organ dysfunction was observed, severe AHRF persisted. Moreover, O 2 A-a grad of 30 mmHg and positive bedside contrast saline echocardiography confirmed the HPS diagnosis. In this study, we discuss the diagnostic approach of HPS and the increasing relevance of contrast saline echocardiography at the bedside, particularly in critically ill patients. The performance of this technique by trained intensivists at the bedside in the ICU minimises critical moments, such as the time required for intra-hospital transport of patients for complementary examinations, considering they have severe ventilatory compromise, thereby allowing HPS diagnosis with high sensitivity.