Role of Point-of-Care ultrasound (POCUS) in clinical hepatology

Hospitalized patients with cirrhosis frequently require critical care management for sepsis, hepatic encephalopathy, respiratory failure, acute variceal bleeding, acute kidney injury (AKI), shock and optimization for liver transplantation (LT), while outpatients have unique care considerations. Point-of-care ultrasonography (POCUS) enhances bedside examination of the hepatobiliary system and relevant extrahepatic sites. POCUS includes cardiac ultrasound and is used to assess volume status and hemodynamic parameters like cardiac output, systemic vascular resistance, cardiac contractility, and pulmonary artery pressure, which aid in the early and accurate diagnosis of heart failure, cirrhotic cardiomyopathy, porto-pulmonary hypertension, hepatopulmonary syndrome, arrhythmia, and pulmonary embolism. This also helps in fluid management and vasopressor use in resuscitation of patients with cirrhosis. Lung ultrasound can help in differentiating pneumonia, effusion, and edema. Further, ultrasonography guides interventions such as line placement, drainage of abdominal collections/abscesses, relief of tension pneumothorax, drainage of pleural and pericardial effusions, and biliary drainage in cholangitis. Additionally, its role is essential to assess liver masses, foci of sepsis, for appropriate sites for paracentesis, and to assess for vascular disorders such as portal vein or hepatic vein thrombosis. Renal ultrasound can identify renal and post-renal causes of AKI and aid in diagnosis of pre-renal AKI through volume assessment. In this review, we address the principles and methods of POCUS in hospitalized patients and in outpatients with cirrhosis and discuss the application of this diverse modality in clinical hepatology.