Cultural Influence of Postoperative Pain

Different cultures can influence how people experience and manage pain after surgery. This study is comparing the amount of opioid (morphine) pain medication used by Chinese patients after major abdominal surgery in two cities — Hong Kong and Hangzhou, China — to see if cultural differences within the same ethnic group affect pain tolerance, beliefs about pain, and how much pain medication is needed. You may be eligible if: - You are between 18 and 80 years old - You are having major abdominal surgery with a wound incision greater than 10 cm - You have strong Chinese heritage and have lived in either Hong Kong or Hangzhou for most of your life - You agree to receive patient-controlled analgesia (PCA) with morphine for at least three days after surgery You may NOT be eligible if: - You are unwilling or unable to use patient-controlled analgesia (PCA) - You have an allergy to morphine, paracetamol, or anti-inflammatory drugs - You have severe kidney or liver disease - You have had chronic pain for more than 3 months in the 6 months leading up to surgery - You have needed opioid pain medication in the 2 weeks before surgery Talk to your doctor about whether this trial might be right for you.