On the 14th, I published an “unknown”, and challenged you to make the diagnosis. I am gratified that it got so many comments, and that people are interested in getting to the answer.
The correct answer is: left diaphragm rupture with herniation of the stomach and colon into the left hemithorax, with mediastinal shift. There are marked-up copies of the original in the extended entry to illustrate what we’re seeing, and to answer a few questions asked in the comments.
The patient was very short of breath, which was handily relieved by putting his bed into “reverse trendelenberg”, making his feet lower than his head. This caused the abdominal contents to stop compressing so much lung, and probably allowed the heart and great vessels to resume their normal position.
He went to the OR, and had his torn diaphragm repaired, a splenectomy, and his two pericardial tears fixed, leaving a pericardial window.