Push enteroscopy

What is it, and what is it for?

An enteroscopy is a flexible camera test that is similar to a gastroscopy, but is performed with a longer camera that allows examination further into the small bowel, usually when an abnormality has been detected by another test such as a CT scan or capsule endoscopy.  It takes around 15 minutes, and patients go home the same day.  It involves gently passing a long, thin flexible telescope through the mouth, down the gullet and through the stomach, and then approximately 70-100 cm into the small bowel before carefully withdrawing it.  Sometimes small tissue samples (‘biopsies’) are taken with tiny forceps, which does not cause any discomfort. 

Occasionally extra growths of tissue or ‘polyps’ are seen in the small bowel and these can be painlessly removed with the camera.

Other procedures can be carried out during a push enteroscopy: 

  • Inflammatory narrowings  of the small bowel, usually caused by Crohn’s disease or chronic anti-inflammatory pain killer use, can cause symptoms of abdominal pain and bloating which can be improved with gentle stretching (‘dilatation’) using a balloon passed through the camera
  • Symptoms from cancerous narrowings of the small bowel, usually caused by tumours elsewhere (pancreas or other advanced abdominal malignancies) can be improved by placing an expandable wire mesh tube (‘stent’) across the affected area
  • Bleeding areas, mainly due to vascular lesions, of the small bowel can be identified and treated effectively.

What are the alternatives?

Contrast x-ray of the small bowel (‘barium follow through’) or small bowel magnetic resonance imaging (‘MRI’) can pick up abnormalities within the small bowel but may miss more subtle lesions, and do not allow tissue samples to be taken or other treatments to be delivered.

Is there anything I need to do before the test?

It is very important that the stomach and small bowel is clear or food prior to a push enteroscopy so that problems are not missed and to minimise the risk of vomiting during the procedure.  For most people a six hour fast (both food and drink) is all that is required – for a morning procedure you should take nothing by mouth from midnight the night before.  For an afternoon procedure you can take an early (7am) light breakfast and then nothing by mouth until after.  If you take warfarin or clopidogrel (blood thinners), or are diabetic, the doctor will give you some specific advice when you see him in clinic about what to do with your tablets.

What will I feel during the test?

The test is usually performed under mild sedation.  This requires a needle in the arm and an injection of a mild sedative.  You will be awake but drowsy.  The test itself takes around 15 minutes.  You may feel the camera at the back of the throat before it passes into the gullet and it may cause you to gag until the camera has passed down.  The test does not affect your breathing and you can breathe freely throughout.  Once the camera is in the gullet the gagging/retching often improves.  It is not painful but you may belch wind or retch during the procedure – this is normal and not dangerous.  More complex procedure (dilatation of strictures, insertion of stents, removal of polyps etc) can increase the duration of the procedure.

What happens after the test?

After the test you may feel slightly drowsy for an hour or if you have had sedation.  Although you may feel  normal after this the drugs are still in your system for 24 hours and you should not drink alcohol, drive a car, go swimming, sign legal documents etc. within this period.  You may feel bloated after the test – this passes fairly quickly.  You will be allowed to drink after the test as soon as you are awake enough for it to be safe.  You can eat normally as soon as you feel up to it.  Usually patients are allowed to go home an hour or so after the test, when they are feeling awake enough and have had something to eat and drink.

Are there any risks?

Push enteroscopy is a safe procedure and the risks, although present, are very small.  A common problem is a sore throat, caused by retching during the procedure, which usually wears off within 24-48 hours.  The main serious complication is damage (‘perforation’) to the back of the throat, gullet, stomach or small bowel as the camera passes down.  This can occur after a routine diagnostic procedure but is incredibly rare, in the order of one in several thousand procedures.  The risk is higher if small bowel polyps have been removed, narrowings have been stretched (‘dilated’) or stents inserted, with a risk of up to 1 in 100 procedures.  A perforation might be suspected if there is significant pain following the procedure that is not getting better.  If suspected, a chest x-ray or CT scan would be performed, and the patient may be kept in hospital overnight.  If confirmed, an operation may be required although a small perforation may seal itself with gut rest and antibiotics.  There is a tiny risk of bleeding following diagnostic enteroscopy, in the order of one in several thousand procedures, but the risk is higher following removal of small bowel polyps or stretching (‘dilatation’) of narrowings.