A member of the 'Blues' gang was rushed into an emergency room after receiving a knife wound in the left side of his thorax. The diagnosis was pneumothorax and a collapsed lung. Explain exactly a. why the lung collapsed, and b. why only one lung (not both) collapsed.

Video transcript

Hello, everyone and welcome to today's video. So which of the following statements best describes the mechanism of lung collapse in situations where abnormal communication forms between the outside environment and the plural. As answer choice is a, we have the abnormal communication disrupts the production of surfactant leading to all the other collapse. B the abnormal communication causes an accumulation of fluid within the plural space. Compressing the lung C the abnormal communication allows the air to enter the plural space leading to increased pressure and lung compression and the the abnormal communication damages the bronchial tree impairing air flow and resulting in lung collapse. Now, something that we need to understand in order to solve this problem is that we normally have this plural space, which is going to be this air tight space between the PLU which are the thin membranes that cover the lungs and the chest wall, which is normally going to be maintaining a negative pressure helping to keep the lung expanded during inspiration. However, when we have abnormal communication, which is normally going to happen when we have a puncher or a wound in the chest. Well, this is going to create an opening that allows air from the outside environment to enter the plural space, which is going to disrupt their normal negative pressure, which is going to lead to the accumulation of air in the plural space, which is known as neural or new moto. Now, as air accumulates in the plural space, we're going to increase the pressure within that space. This negative pressure is going to start increasing. Now, this increased pressure is going to compress the lungs, preventing them from fully expanding during inspiration. And finally, this lung compression is going to result in the in lung collapse and impairs the ability to perform normal respiratory functions for the lungs. So this is how this lung collapse is going to be occurring in situations where the abnormal communication forms between the outside environment and the plural. We're going to have this air enter the plural space leading to increased pressure and lung compression, which like we said, eventually leads to lung collapse. So the correct answer here for this question is the abnormal communication allows the air to enter the plea leading to increased pressure and lung compression. I really hope this video helped you and I hope to see you on the next one.