The study is aimed to explore the effects of multimodal analgesia consisting of ropivacaine's wound infiltration, parecoxib's intravenous injection and oxycodone-acetaminophen tablets' oral administration on postoperative pain and rehabilitation after laparoscopic radical gastrectomy for patients with gastric cancer.

Postoperative pain attracts the attention of surgeons, and optimal postoperative pain management contributes to reducing complications and accelerating postoperative rehabilitation. Traditionally, the opioids were used for postoperative pain control. However, the opioids may increase the time to recover bowel function and lead to postoperative ileus. Multimodal analgesia is recommended in recent years, but studies on multimodal analgesia after gastrectomy are scarce. In this study, we introduced a multimodal analgesia strategy consisting of incision infiltration with ropivacaine, intravenous injection of parecoxib, and oral administration of an oxycodone/paracetamol mixture and evaluated the effects of this strategy compared with PCIA analgesia which is used widely for pain after gastrectomy.

Inclusion Criteria:

1. Requirements of informed consent and assent of participant, parent or legal guardian as applicable.
2. Patients underwent laparoscopic radical gastrectomy under general anesthesia and between the age of 18 and 75 years old without considering sex.
3. American Society of Anesthesiologists (ASA) physical status I-III.
4. Participants can follow the drug doses and visit plan

Exclusion Criteria:

1. Patients certified by a doctor that doesn't fit to participate in this study.
2. Patients allergic to opioids, sulfas, parecoxib, non-steroidal drugs, acetaminophen, tramadol etc..
3. Patients with ischemic heart disease, cerebrovascular disease and peripheral vascular disease, or their cardiac function > II (NYHA) patients, patients received coronary artery bypass grafting (CABG) recently, and patients with severe hypertension (systolic pressure≥180mmHg or diastolic pressure≥110mmHg).
4. Patients with gastric cancer with distant metastasis.
5. Patients with severe infection, respiratory dysfunction, coagulation disorders, severe liver and renal dysfunction (Child - Pugh≥ 10; creatinine clearance < 25 ml/min).
6. Patients with suspect or have a history of drug abuse.
7. Pregnancy and lactation women, or have a pregnancy plan within a month after the test of the subjects (also including male participants).
8. Sponsors or researchers directly involved in the testing or their family members.
9. Patients with conversion, palliative resection.
10. Patients with chronic pain（NRS≥3）or using opioids or NSAIDs before surgery.