Ultrasound Assessment of Diaphragmatic Structure and Function in Patients With Liver Cirrhosis: A Point-of-Care Tool for Predicting Complications and Sarcopenia in Limited Resource Settings

The goal of this observational study is to learn how liver cirrhosis affects the diaphragm, the main muscle used for breathing, in adults. The study will measure diaphragmatic thickness, thickening fraction, and excursion using bedside ultrasound and compare these values between patients with cirrhosis and healthy volunteers. The main questions it aims to answer are: Do patients with cirrhosis show reduced diaphragmatic function compared to healthy adults? Does removal of ascitic fluid by paracentesis improve diaphragmatic mechanics? Can ultrasound measurements of the diaphragm serve as a reliable non-invasive marker of sarcopenia when compared to CT scans? Participants will: Undergo diaphragmatic ultrasound during quiet and deep breathing Provide clinical and laboratory data related to liver disease severity In some cases, have ultrasound repeated before and after paracentesis For patients with hepatocellular carcinoma, CT scans will be analyzed to measure muscle mass

Inclusion Criteria: 1. Age ≥18 years. 2. Confirmed diagnosis of liver cirrhosis based on clinical, biochemical, histological, or imaging criteria. 3. Ability to provide written informed consent in Arabic or English. 4. For Subgroup A: clinical indication for large-volume paracentesis with an ascitic volume of ≥5 liters. 5. For Subgroup B: confirmed hepatic hydrothorax or confirmed absence of pleural effusion on ultrasound or chest X-ray. 6. For Subgroup C: radiologically confirmed HCC by triphasic CT or MRI according to EASL/AASLD diagnostic criteria, with available CT imaging for L3 SMI analysis. Exclusion Criteria: 1. Significant pre-existing primary pulmonary disease (e.g., moderate-to-severe COPD defined as FEV1/FVC \