343.A 23-year-old, semiconscious man is brought to the emergency room
following an automobile accident. He is tachypneic and cyanotic. The right
lower anterolateral thoracic wall reveals a small laceration and flailing. Air
doesnotappear to move into or out of the wound, and it is assumed that the
pleura have notbeen penetrated. After the patient is placed on immediate pos-
itive pressure endotracheal respiration, his cyanosis clears and the abnormal
movement of the chest wall disappears. Radiographic examination confirms
fractures of the fourth through eighth ribs in the right anterior axillary line and
of the fourth through sixth ribs at the right costochondral junction. There is
noevidence that bony fragments have penetrated the lungs or of pneumotho-
rax (collapsed lung). The small superficial laceration, once it is ascertained
that it has notpenetrated the pleura, is sutured and the chest bound in ban-
dages; positive pressure endotracheal respiration is maintained. Several hours
later, the cyanosis returns. The right side of the thorax is found to be more
expanded than the left, yet moves less during respiration. Chest x-rays are
shown below.
Thorax 465A B