The presence of free air either in the chest or abdomen is a frequent complication of disease and therapy in the neonatal setting. All exams should be thoroughly scrutinized for the presence of pneumothorax, pneumomediastinum, or pneumoperitoneum. If there is any question in this regard, a decubitis CXR, with the side of interest upright, should be obtained to evaluate for a pneumothorax. If free intraperitoneal air is a question then a left side down decubitis abdomen exam should be obtained. If the child cannot be positioned for the decubitis exam then a cross table lateral chest XR or abdominal XR will suffice.