The goal of this clinical trial is to learn about the effects on postoperative analgesia of continuous lidocaine infusion via closed chest drainage tube for patients undergoing thoracoscopic partial lung resection. The main questions it aims to answer are:

• To explore whether continuous lidocaine pumping via closed chest drainage tube has good analgesic and anti-inflammatory effects for patients undergoing partial thoracoscopic pneumonectomy.
• Whether the multimodal analgesia combined with continuous lidocaine pump can reduce the postoperative application of opioids, reduce the occurrence of postoperative complications, and promote the recovery of postoperative lung function and accelerate recovery.

For participants who undergoing the thoracoscopic partial lung resection with postoperative indwelling drainage tube, the epidural tube fixed in the drainage tube is connected to the completed infusion pump (marking the chest drain for analgesia). The comparison group only accept the intravenous analgesia after surgery.

At present, multimodal analgesia has been the most commonly used approaches for the treatment of postoperative pain of thoracic surgery, including steroidal anti-inflammatory drugs, administration of opioid, and local anesthesia.

The investigators found that continuous lidocaine analgesia with local anesthesia through thoracic closed drainage tube could improve postoperative pain caused by drainage tube retention, reduce postoperative pain score, and improve postoperative recovery of respiratory function in patients. In the protocol, lidocaine was continuously pumped with a superficial anesthetic effect on the pleura, while mucosal absorption was almost equivalent to intravenous infusion, so its systemic anti-inflammatory effect is also explored.

In the protocol，participants will be randomized in a 1:1 ratio to the control or experimental groups. The experimental group received a continuous infusion of lidocaineThe experimental group used 2% lidocaine 100ml, and the control group was the conventional treatment group. The control group received only standard intravenous analgesia。In addition to receiving simple intravenous analgesia, the experimental group also received continuous infusion of lidocaine in the pleural cavity.

Inclusion Criteria:

1. participants ages 18-70 years.
2. participants undergoing thoracoscopic partial lung resection with an indwelling drainage tube after surgery.
3. American Society of Anesthesiologists classification (ASA)I-III.

Exclusion Criteria:

1. severe heart failure, cardiac arrhythmias,the New York Heart Association(NYHA) classification≥III.
2. hypersensitivity to lidocaine,History of local anesthetic poisoning.
3. severe renal or hepatic dysfunction.
4. body mass index (BMI)>35 kg m-2.
5. severe pleural adhesions.