Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Subcutaneous emphysema along the left chest wall is again noted . In this patient with recent stab wound , left pleural effusion likely represents hemothorax , small to moderate in volume with associated compressive lower lobe atelectasis . Right lung is clear . Cardiomediastinal silhouette appears grossly unremarkable though the left heart border is partially obscured . Bony structures are intact .
    OUTPUT:
    
Left basal opacity compatible with mild to moderate hemothorax and adjacent consolidation likely atelectasis . Left chest wall subcutaneous emphysema as on recent CT chest .