A colonoscopy is an examination that allows doctors to investigate the colon and the inner lining of the intestine and is carried out using a colonoscope, which is a flexible tube. The colonoscopy usually takes around 20-30 minutes and during the test a tissue sample, known as a biopsy, may be taken for analysis at the laboratory. In some cases, polyps, small projections from the wall of the intestine, which are similar to warts, may also be removed and if this is the case the test may take slightly longer. After the procedure patients are usually free to go home.
In order for Dr Bansi to have a clear view of the colon it must not contain any faeces and for this reason it is important that patients follow the preparation instructions very carefully. If bowel preparation is done incorrectly, the test may have to be postponed or repeated. It is important to tell members of staff if you are taking any form of medication and in most cases, doctors will advise you to continue to take your medication, although in some cases, special preparation may be required. If you are diabetic it is very important to notify staff as you may be advised to follow a special diet.
The colonoscopy procedure
When you arrive you will be greeted by a member of staff and a nurse will check your pulse, take your blood pressure and ask you a few questions and you will then be asked to change into a hospital robe. You should tell your nurse about any medication you are taking and notify them of any allergies and if you wear false teeth, you will be asked to remove them for the procedure.
The procedure should not be painful but it may be uncomfortable as the colonoscope moves around corners, but any discomfort should wear off very quickly. Before the colonoscope is inserted, painkillers and a sedative will be given and a small device will be attached to your finger to monitor your pulse and breathing rate.
The colonoscope is inserted into the back passage and manoeuvred around the bowel. Air will be inserted into the colon to allow Dr Bansi to get a clearer view and this sometimes gives patients the sensation that they want to empty their bowel. If this is the case and you pass wind, do not be embarrassed, as your doctors and nurses will be used to this.
Alternatives to a colonoscopy
Colonoscopy still considered the gold standard for assessing the colon because it allows both diagnostic and allows then to take a biopsy. However CT colograpghy (virtual colonoscopy) may be an alternative or adjunct in certain situations.
After the procedure
Sedatives can make you feel drowsy and weary for a period of time so you may feel tired after the procedure. Your doctor will talk to you after the procedure but if you are feeling tired they can always talk to a friend or relative instead and it is always advisable to attend a follow-up appointment. You may experience a feeling of bloating after the procedure but this should alleviate over the course of the day, If you have had polyps removed or a biopsy taken you may pass a small amount of blood, which this is normal, but if you start to bleed excessively you should arrange to see a doctor as soon as possible.
It is advisable to avoid driving, operating heavy machinery or making important decisions for 24 hours after the procedure and it is a good idea to ask a friend or relative to take you home and stay with you until you come round properly.
The colonoscopy is regarded as a very safe procedure but as with all procedures there is a small risk of side-effects. Side-effects with colonoscopies are uncommon but may include damage to the intestine by the colonoscope, allergy to medications used prior to the procedure, suppression of breathing due to sedatives and aspiration pneumonia. If the intestine has been damaged, surgery may be required. In certain cases, for example in patients with respiratory illnesses or heart disease, the procedure may be stressful and this may increase the risk of complications and the risk will also be increased if tissue samples are taken or polyps are removed. Although the test is usually very effective it is possible that abnormalities can be missed.
It is important to follow the instructions below carefully to ensure that the bowel is clear of faeces and doctors are able to get a clear view of the colon:
- Avoid taking iron tablets or fibre supplements, such as Fybogel and Regulan for at least 7 days before the procedure
- Avoid eating foods that are high in fibre such as fruit, vegetables and nuts for 4 days before the test
- Use Picolax and increase your intake of fluids 24 hours before the test, avoid eating solid foods (stick to tea, glucose drinks and coffee) for 24 hours prior to the test. At 6pm the evening before the test take a dose of Picolax and drink a glass of water. At 8am the next day take the second dose of Picolax and take a third dose at 10am.
- If you suffer from constipation you may require additional doses. If you have any questions or doubts, talk to your doctor.