Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There has been interval placement of a left - sided chest tube with tip projecting over the medial aspect of the left lung base . There is continual residual atelectasis in the left lung base with probable small hemothorax , though extent of residual pneumothorax is difficult to assess on this supine study . Extensive subcutaneous gas in the left chest wall persists with subcutaneous emphysema also noted coursing cephalad along the fascial planes of the neck bilaterally . Cardiac and mediastinal contours are similar with no rightward shift of mediastinal structures . Minimal atelectasis is noted in the right lung base . Known multiple left - sided rib fractures are better assessed on the previous CT . Left - sided pacemaker device with leads terminating in the right atrium and right ventricle is again noted .
    OUTPUT:
    
No substantial interval change status post placement of new left - sided chest tube .