A penetrating open chest wound to the left side with no other injuries is not properly treated. What is the most likely outcome?

A penetrating open chest wound to the left side with no other injuries is not properly treated. What is the most likely outcome?

• A. Casualty's left lung will collapse
• B. Right lung collapse
• C. Both lungs collapse
• D. No effect on lungs

Answer: (A)

When air can enter the chest cavity through a penetrating wound on one side, the pleural space on that side loses its negative pressure. That negative pressure normally keeps the lung expanded. With the wound open, air accumulates in the left pleural space, the left lung cannot stay inflated, and it collapses. The right lung remains expanded because its pleural space is still intact. So, without treatment, the most likely immediate outcome is the collapse of the left lung.

When air can enter the chest cavity through a penetrating wound on one side, the pleural space on that side loses its negative pressure. That negative pressure normally keeps the lung expanded. With the wound open, air accumulates in the left pleural space, the left lung cannot stay inflated, and it collapses. The right lung remains expanded because its pleural space is still intact. So, without treatment, the most likely immediate outcome is the collapse of the left lung.