Possible causes of gas leakage from the lungs after lung surgery include incisions that have not healed, bacterial infections, or cracked suture sites. 1. Non-healing incision: The incision may not heal due to physical weakness, and gas leaks out from it. 2. Bacterial infection: Bacterial infection after surgery causes infectious inflammation at the incision site, which causes gas to leak out of the incision site suture and leads to air leakage from the lungs. 3. Split suture site: the suture site is split for some reason, and gas enters the chest cavity through the split. There may be other reasons for lung leakage after lung surgery, such as: poor closure of the drainage tube, etc., you should go to the regular hospital in time, and the doctor will judge the reason according to the specific situation and then carry out targeted treatment.