Actually, the examination methods for hemothorax and pneumothorax are quite simple. From their definitions, we know that hemothorax means the abnormal presence of blood in the pleural cavity, and pneumothorax means the presence of gas in the pleural cavity where it shouldn't be. Therefore, the simplest examination is an X-ray, a standard frontal and lateral chest X-ray, which usually costs about 52 yuan, can detect whether a patient has pneumothorax. As for hemothorax, of course, it involves the use of a syringe. After injecting some lidocaine local anesthesia into the patient, if blood is withdrawn from the pleural cavity, then it indicates a hemothorax. Thus, the first step in examining for hemothorax and pneumothorax is to perform an X-ray to check for the presence of gas. If gas is detected, then it is pneumothorax. If liquid is found, a syringe under ultrasound guidance can be used to withdraw it. If the withdrawal yields fluid, it indicates pleural effusion; if blood is drawn, then it indicates hemothorax.