Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient remains intubated . An orogastric tube terminates in the stomach . The cardiac , mediastinal and hilar contours appear stable . There is increasing retrocardiac opacity on the left suggesting atelectasis . There is no evidence of pneumothorax . Rib fractures were better characterized on the recent prior CT and do not show any clear increase in displacement .
    OUTPUT:
    
Patchy opacity at the left lung base indicating atelectasis . No visible pneumothorax . Left - sided rib fractures .