A prospective study to compare the postoperative ileus in open and laparoscopic gastrointestinal surgery through the determination of the time the patient takes to pass flatus, pass stool, bowel movement, oral intake, the time of hospital stay and total hospital costs. Postoperative ileus (POI) is one of the major focus of concern for surgeons, hospital executives, quality assurance directors as well as patients because of its role in causing patient distress, discomfort, and morbidity, leading to an increase in the duration of hospital stay and cost of care.

All patients aged ≥18 years scheduled to undergo gastric and colorectal cancer resection surgery at the Department of Gastrointestinal Surgery, West China Hospital between 2019 to 2020 will be screened for eligibility. The inclusion criteria for the study will be the patient undergoing elective gastric cancer surgery, have the American Society of Anesthesiologist (ASA) grade ≤ III, alert consciousness, and BMI, and accurate preoperative diagnosis of gastric adenocarcinoma on the basis of computed tomography CT scan report, Gastroscopy and Histopathological reports. Exclusion criteria will be those who cannot participate in study assessments owing to the language barrier, dementia or postoperative delirium; previously received palliative surgery, develops early postoperative bowel obstruction, Anastomotic leakage or Gastroparesis, those requiring reoperation for any other indication before the commencement of formal assessment for PPOI. Those requiring more than 30 minutes of adhesiolysis. Each patient will be approached during preoperative counseling on an individual basis by one of the authors (YZ)

Inclusion Criteria:

• Patients aged ≥18 years scheduled to undergo elective abdominal surgery
• American Society of Anesthesiologist (ASA) grade ≤ III
• Alert consciousness
• Any BMI
• Accurate preoperative diagnosis on the basis of necessary reports

Exclusion Criteria:

• Cannot participate in study assessments owing to the language barrier, dementia or postoperative delirium
• Previously received palliative surgery
• Develops early postoperative bowel obstruction, Anastomotic leakage or Gastroparesis
• Those requiring reoperation for any other indication before the commencement of formal assessment for POI
• Those requiring more than 30 minutes of adhesiolysis
• Emergency cases
• American Society Anesthesia (ASA) class IV or V patients, pregnancy, patient with abdominal carcinomatosis or radiation enteritis, inoperable cases due to metastasis, patients simultaneously enrolled in any other competing for clinical study and violation of study protocol by the patient or patient care team

All eligible patients enrolled in this study would undergo gastric and colorectal resection surgery