A plastic tube which is called a chest tube is inserted into the chest wall and pleural space. It can remove the air such as pneumothorax, fluid for fluid effusion and hemothorax. There are 2 or 3 chambers yet would depend on the situation. The first would be to remove the air or fluid followed by preventing drained fluid or air from returning thus the nurse should consider having it in a negative pressure for lung re expansion.
You never want to lower you want to always progress higher and higher