Since the air leak and lung collapse are persisting despite chest tube drainage, the next step is to address the leak directly. The most effective approach is a minimally invasive procedure, such as Video-Assisted Thoracoscopic Surgery (VATS), to seal the leak and perform pleurodesis (bonding the lung to the chest wall to prevent future collapse). If surgery is not advisable, chemical pleurodesis through the chest tube or placing temporary bronchial valves are excellent alternatives. Additionally, keeping your blood sugar strictly controlled is vital for tissue healing, and quitting smoking is crucial. Please consult a cardiothoracic surgeon to discuss these highly effective, definitive options.