Lung lavage is a colloquial term for what is medically called alveolar lavage, which is the injection of saline into the distal bronchi and alveoli through a bronchoscope and deposition for a period of time, followed by aspiration through the bronchoscope to play a lavage role, and is commonly used to treat patients with alveolar protein deposition. Alveolar lavage is an invasive operation, so there are certain operational risks, such as most commonly causing hypoxia and hypoxemia; irregular operation may induce infection; the operation requires anesthesia, so there is a risk of anesthetic allergy; it may also cause tracheal bleeding, leading to hemoptysis; the operation has to pass through the pharynx can cause damage to the pharynx, leading to laryngeal edema; it can also cause spontaneous pneumothorax It can induce bronchial asthma; in serious cases, it can lead to esophagotracheal fistula and even death.