A young diver who had suffered an accident with broken ribs and a pneumothorax called DAN to find out why he could no longer dive. What is the risk of a spontaneous pneumothorax? Could pleural scarring cause problems?
The lungs are contained within the chest and protected by the pleural membrane. The pleura lines the outside of the lungs and the inside of the chest cavity, leaving a space between the two layers. If air enters the area between the pleural tissues, the space fills and expands, reducing the lungs' ability to expand, compromising breathing. If the air comes from an internal wound, it is a closed pneumothorax . If the wound is external, it is an open pneumothorax.
The tear could be caused by a lung defect or an accident. The larger the hole, the faster the pneumothorax will progress. If the hole is small, the pneumothorax could close on its own, and the air would gradually be reabsorbed by the body. If the internal wound does not close and air continues to enter the space between the membranes, a condition called tension pneumothorax occurs : the gas volume expands, compressing the lungs and heart. This is a very dangerous situation and requires immediate intervention. If it were to happen to a diver underwater, the increased pressure in the pleural space would be aggravated by the expansion of the gas during ascent.
Can pneumothorax recur?
A pneumothorax can result from blunt trauma to the chest that causes the pleura to tear, much like bursting an inflated paper bag. What are the chances of the pleura tearing again, causing a spontaneous pneumothorax?
If the accident is similar to the one just described, the injured area should heal completely within a few months, with a very low risk of spontaneous pneumothorax. The lung itself should not have suffered too much if the laceration involved only the pleural membrane. However, if the chest trauma also causes broken ribs and these perforate the lung, the lung tissue will be severely damaged. Even after healing, the risk of spontaneous pneumothorax during diving is high.
It's always best to undergo a medical checkup before diving again. The presence of any abnormal shadow within the lung, detected by X-rays or a CT scan, indicates the risk of air retention and reduced elasticity. In this situation, the likelihood of pulmonary barotrauma while diving is too high.
Spontaneous pneumothorax can occur without warning, even in apparently healthy people. The cause is a lung defect, which may be congenital or develop later in life. This type of condition is quite common, and those affected should not dive. If it occurs while diving, the air escaping from the lungs finds itself in a confined space that cannot be equalized during ascent. Furthermore, as the external pressure decreases, the gas expands, interfering with the function of the heart and lungs.
Article by Richard Moon, G. Yancey Mebane, from Alert Diver, DAN magazine.
If you have any questions about this topic, please don't hesitate to ask. to call the DAN doctors!
