Care at NUH



What is a Gastroscopy? 

Oesophago-Gastro-Duodenoscopy (OGD), commonly known as Gastroscopy, is a procedure enabling doctors to examine the lining of the oesophagus, stomach and the duodenum (the initial segment of the small intestine). This examination is performed in the endoscopy suite using a soft, flexible tube, which is thinner than a finger, gently inserted through the mouth. The procedure employs a video camera, allowing the doctor to thoroughly inspect the upper gastrointestinal tract. 

Who should have a Gastroscopy? 

Gastroscopy is advisable for individuals needing: 

  • Gastric cancer screening 
  • Assessments for ulcers / polyps 
  • Evaluation of upper abdominal discomfort and pain 
  • Examination in cases of anaemia or gastrointestinal bleeding 
  • Investigation of swallowing difficulties 
  • Assessment of reflux and heartburn symptoms 

Patients must fast for at least six hours before the procedure to ensure an empty stomach, crucial for effective gastroscopy. An empty stomach provides clear visualisation and reduces vomiting risks during the examination. The presence of food may necessitate rescheduling the procedure. 

Patients should consult their doctor regarding medication continuation, particularly for blood thinners, warfarin, aspirin or diabetes medication. 

How is a Gastroscopy performed? 

The procedure begins with the administration of a local anaesthetic spray to numb the throat, followed by optional light sedation for relaxation. The doctor then gently advances the gastroscope though the mouth into the stomach. The entire process typically takes about 10 minutes. 

Patients might experience mild bloating or belching due to air inflation in the stomach. The procedure is pain-free, well-tolerated and does not affect breathing. 

What happens after a Gastroscopy? 

Post-gastroscopy, patients are observed until the effects of sedation subside and are then discharged. It is advised not to drive or operate machinery until the next day due to sedative effects.  

Mild bloating from the introduced air and occasional mild sore throat may occur, usually resolving within a few days. Normal eating can resume on the same day and regular activities can continue the following day. 

What are the risks? 

Gastroscopy is a safe procedure with infrequent complications. However, risks include bleeding from a biopsy site, perforation or aspiration of stomach contents. Fasting minimises aspiration risks. Some patients may react to sedation. In cases of severe chest or abdominal pain, fever, or bleeding, it is crucial to contact a doctor immediately. 

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