Hyperinflation of the lungs means air is trapped in the small airways so the lungs appear larger than usual on the chest x-ray. This
simplySimply sleep means that you were breathing hard when the chest x-ray was taken. In the short term, it really does not mean anything serious. This is a very common finding when asthma is poorly controlled, like during an asthma attack. This same finding is seen in the lungs of chronic smokers. It can also be due to a virus. Unless you are a long time smoker, the hyperinflation may mean nothing more than that you need to be checked to be sure your asthma is optimally controlled.