Q: I was in an automobile accident last year and suffered a pneumothorax. Can I go back to diving and when?

A: This is an excellent question and a very important one. A pneumothorax is essentially a collapsed lung, which may be entirely or only partially collapsed. When the chest wall is injured, as in your case, the normally sealed lung cavity is breached, forcing the lung to decrease in volume. Through a combination of repairing the injuries and putting a drain tube in the chest cavity, the lung will re-expand, and things will return to normal. Other ways to suffer a pneumothorax include an overexpansion of the lungs due to a rapid ascent during a dive or with a spontaneous rupture of a defect in the lung itself (called blebs).

After a period of healing and with appropriate follow-up, which may include pulmonary-function testing and radiographic imaging, individuals who have suffered a pneumothorax due to trauma or while diving can safely return to diving. The same cannot be said for those who sustain a pneumothorax due to defects in the lung tissue itself, known as a spontaneous pneumothorax. Very frequently there are multiple blebs on one or both lungs. The risk of suffering a second spontaneous pneumothorax is significant and could be potentially catastrophic if it occurs during a dive.