Final answer:
Orogastric tubes are inserted for aspirating stomach contents, medication administration, diagnostics, or providing nutrition. Tube size varies by patient and purpose, with common adult sizes ranging from 16 to 18 French. Diagnostic procedures for issues like peptic ulcers may use an endoscope instead.
Step-by-step explanation:
An orogastric tube should be inserted when it is necessary to aspirate stomach contents, administer medication, perform diagnostics, or provide nutritional support to a patient who cannot intake food orally. This procedure is often done in emergency situations, for gastric decompression, or during surgeries. The size of the tube used depends on the patient's size and the specific purpose of the tubing; for adults, a common size can be between 16 to 18 French, and for children, a size appropriate to their stature is selected, typically smaller.
For diagnostic purposes such as checking for peptic ulcers, an endoscope may be used instead, which is a type of tube with a camera that allows viewing of the upper GI tract. Orogastric tube insertion is a different procedure where the tube is pushed down the throat into the stomach and possibly the upper part of the small intestine. During this process, secretin can be administered, and contents of the duodenal secretions are aspirated and analyzed for diagnostic purposes.