How to treat pleural effusion after lung nodule surgery is related to the amount of effusion. If the amount of effusion is small, it can be self-absorbed or drained out through a drainage tube; however, if the amount of effusion is large and accompanied by obvious uncomfortable symptoms, it is generally recommended to choose thoracocentesis to extract fluid for treatment. Pleural effusion after lung nodule surgery may be related to surgical trauma, infection (which may cause increased inflammatory exudation in the chest cavity), etc. If the amount of effusion is small and there is no obvious discomfort, it can be absorbed on its own or the drain can be left in place for 1-3 days, and the drain can be removed if the amount of fluid drained is less than 50-100 ml. For pleural effusion caused by infection after lung nodule surgery, if the amount of effusion is large and accompanied by symptoms such as chest tightness and shortness of breath, intravenous penicillin sodium can be chosen for anti-infection, and at the same time, thoracentesis can be used to draw out the pleural effusion to reduce the patient’s symptoms. For patients with pleural effusion found after lung nodule surgery, it is recommended to follow the physician’s advice to choose the appropriate treatment plan according to their own specific conditions, and not blindly self-medication.