Transthoracic Ultrasound of Parasternal Intercostal Muscles and its relation with severity of Chronic Obstructive Pulmonary disease

Background Chest wall musculature changes may indicate combined systemic consequences of chronic obstructive pulmonary disease (COPD), which disrupts respiratory mechanics locally due to airflow restriction and hyperinflation. It is possible to assess the amount and make-up of muscles using transthoracic ultrasonography. Aim To study the correlation between parasternal intercostal muscle thickness, COPD severity and the reliability of parasternal intercostal muscle ultrasound. Patients and methods A prospective observational case–control study was conducted on 120 participants; 60 of them were stable COPD patients and 60 healthy controls. Full clinical history taking, spirometry, and transthoracic ultrasound of parasternal intercostal muscle thickness (mm) were carried out on all studied participants. Results Our study revealed significantly lower mean values in the stable COPD group as regards RT second, third parasternal intercostal muscle thickness (mm) compared to controls and a significant positive correlation between forced expiratory volume in first second % and RT second, third parasternal intercostal muscles thickness (mm). The receiver operating characteristics curve reported that RT second and RT third parasternal intercostal muscle thickness cut-off value less than 5.7, with accuracy of 82.5and 79.2%, respectively, were found. Conclusion A decrease in parasternal intercostal muscle thickness was observed in stable COPD patients. Parasternal intercostal muscle thickness could be a predictor for COPD severity. Transthoracic ultrasound could be reliable in the assessment of the parasternal intercostal muscle.