Inclusion Criteria:  1) Preoperative pathologically confirmed colorectal adenocarcinoma; 2) Patients undergoing minimally invasive (robot or laparoscopic) tumor resection + bowel anastomosis; 3) Age: 18 to 80 years old; 4) Preoperative TNM staging (whole abdomen) Enhanced CT or MRI, laparoscopic exploration): cT1-3bN0-2M0; 5) Preoperative ASA score: ≤Ⅲ; 6) No history of malignant tumors and no other malignant tumors by preoperative examination; 7) Not accepted before surgery Deterministic treatment, such as radiotherapy, chemotherapy or immunotherapy; 8) No pre-existing ascites was found before and during the operation; 9) Informed consent signed by the patient or his agent  Performance status (ECOG) 0~1  Exclusion Criteria:  1) Patients with obstructive jaundice or other congenital disorders of bile acid synthesis and metabolism; 2) Severe abdominal cavity infection and other infections; 3) A large amount of abdominal effusion was found before and during the operation; 4) Tumor was confirmed during the operation For T4b or intraoperative detection of other tumors, joint resection or distant metastasis is required; 5) Intraoperative conversion to laparotomy; 6) Intraoperative change of surgical method to perform Miles or Hartmann surgery; 7) Intraoperative and postoperative abdominal cavity Hyperthermic perfusion chemotherapy.