Following a trauma, doctors
in an emergency room follow a very specific protocol depending on the type of injuries that are sustained. They first make sure that the patient has a stable airway and that the patient's breathing and circulation are intact. If the patient's breathing is impaired, a physical exam and/or imaging with chest x-ray
or CT scan is performed to determine the cause and ensure that lungs are not compromised by excess buildup of fluid. If the abdomen is involved, an ultrasound is often done to ensure that there is no free fluid in the belly that would require exploration of the wound in the operating room.
While some rib fractures are complicated and can lead to punctured lungs, others are simple, do not cause injury to nearby organs, and are only associated with pain. Similarly, the sternum can be fractured in different ways; a severe fracture could lead to displacement of the bone and put the heart and lungs at risk for injury. A simple non-displaced fracture should heal on its own with time.
It is strongly advised that you and your friend consult with the doctors that cared for him in the hospital or his primary care physician
to obtain further information about the extent or management of his injuries.