The stem
You are the foundation doctor on a surgical ward. A nurse hands you this and asks you to place it in a patient admitted with small bowel obstruction.
The equipment
The examiner’s questions
Question 1What is this, and what is it used for?Show the model answer
A wide-bore nasogastric tube (a Ryles tube). In surgery it decompresses the stomach in bowel obstruction, ileus and persistent vomiting, and protects the airway from aspiration. A fine-bore tube is used for feeding.
Question 2How do you decide how far to insert it?Show the model answer
Measure from the tip of the nose to the earlobe and then down to the xiphisternum (the NEX distance), and note the mark on the tube at that length.
Question 3How do you confirm its position before use?Show the model answer
Aspirate and test the pH: 5.5 or below confirms a gastric position. If no aspirate is obtained or the pH is higher, request a chest X-ray. On the film the tube runs down the midline, bisects the carina, crosses the diaphragm in the midline and its tip lies below the left hemidiaphragm. Never use the “whoosh test” of injecting air.
Question 4What are its complications and contraindications?Show the model answer
Placement in the airway, which can kill if feed or fluid is given; nosebleed; sinusitis; oesophageal injury; and loss of fluid and electrolytes, which must be replaced. Avoid the nasal route after a suspected base of skull fracture or major facial fracture, and use the mouth instead.
After you answerThe teaching pointShow
A misplaced nasogastric tube used for feeding or drugs is a never event. Check the position before every use, not only after insertion.
The drawings were made for this site. The patients are written for teaching and are not real.