Risks of the procedure

Lower gastrointestinal endoscopy is classified as an invasive investigation and because of that it has the possibility of associated complications. These occur extremely infrequently; we would wish to draw your attention to them and so with this information you can make your decision

The doctor who has requested the test will have considered this. The risks must be compared to the benefit of having the procedure carried out.

The risks can be associated with the procedure itself and with administration of the sedation.

The endoscopic procedure

The main risks are of mechanical damage; 

•  Perforation (or tear in the bowel wall) risk approximately 1 for every 1,000. An operation is nearly always required to repair the hole. The risk of perforation is higher with polyp removal. 
•  Bleeding may occur at the site of biopsy or polyp removal (risk approximately 1 for every 100-200 examinations where this is performed). Typically minor in degree, such bleeding may either simply stop on its own or if it does not, be controlled by cauterization or injection treatment.
•  Pain - usually this procedure is well tolerated. It is common to experience short lived discomfort, however, a small percentage of patients may experience pain with this procedure.

Sedation 

Sedation can occasionally cause problems with breathing, heart rate and blood pressure. If any of these problems do occur, they are normally short lived. Careful monitoring by a fully trained endoscopy nurse ensures that any potential problems can be identified and treated rapidly. 

Older patients (over 75 years) and those of all ages with medical conditions will be offered an alternative investigation. Mostly this would be a virtual colonoscopy in a CT scan.

What is a polyp? 

A polyp is a protrusion from the lining of the bowel. Some polyps are attached to the intestinal wall by a stalk, and look like a mushroom, whereas others are flat without a stalk. Polyps when found are generally removed or sampled by the endoscopist as they may grow and later cause problems. Flat polyps are generally a little more difficult to remove.

Polypectomy 

A polyp may be removed in several ways using an electrical current known as diathermy. 

For large polyps a snare (wire loop) is placed around the polyp, a high frequency current is then applied and the polyp is removed. 

Flat polyps (without any stalk) can be removed by a procedure called EMR (Endoscopic Mucosal Resection) or ESD (Endoscopic Mucosal Dissection). Alternatively you may be offered an operation for larger polyps. This would take place at a larger stage. 

This involves injecting the lining of the bowel that surrounds the flat polyp. This raises the area and allows the wire loop snare to capture the polyp. 

For smaller polyps biopsy forceps are used to hold the polyp whilst the diathermy is applied, therefore destroying the polyp.

After the procedure 

You will be allowed to rest for as long as is necessary. Your blood pressure and heart rate will be recorded and if you are diabetic, your blood glucose will be monitored. Should you have underlying breathing difficulties or if your oxygen levels were low during the procedure, we will continue to monitor your breathing. Once you have recovered from the initial effects of the sedation (which normally takes 30-60 minutes), you will be moved to a comfortable chair and offered a hot drink and biscuits. Before you leave the department, the nurse or endoscopist will discuss the findings and any medication or further investigations required. She or he will also inform you if you require further appointments.

The sedation may temporarily affect your memory, so it is a good idea to have a member of your family or friend with you when you are given this information although there will be a short written report (discharge letter) given to you. 

Because you have had sedation, the drug remains in your blood system for about 24 hours and you may feel drowsy later on, with intermittent lapses of memory. If you live alone, try and arrange for someone to stay with you or, if possible, arrange to stay with your family or a friend for at least 4 hours. 

If the person collecting you leaves the department, the nursing staff will telephone them when you are ready for discharge.