What is a Colonoscopy?
This is an examination of your large bowel/ intestine via an endoscope (a long flexible fiberoptic instrument with a camera which is 1cm in diameter) your large bowel can be examined from where it is joined to the small bowel right through to where waste matter faeces are expelled, at your anus. The colon consists of your rectum, the colon which is described as the sigmoid colon, descending colon, transverse and ascending colon, you may hear these terms used when the doctor describes parts of your bowel.
This is a procedure can be done as a day case procedure and is usually carried out in a specialised endoscopy unit. The examination is generally being carried out because you may have been experiencing symptoms like:
- Rectal bleeding
- Dark or bright red stools/faeces
- Chronic diarrhoea
- Noticeable changes in your bowel habits
- Stools/faeces are narrower than normal
- Feeling that you have not emptied your bowel completely
- Unexplained weight loss
- Persistent low stomach pains(bloating, cramps, excess wind
The doctor undertaking the examination will be looking for red and inflamed areas, polyps (a growth on a stalk) lesions, ulceration, signs of irritable bowel syndrome and colon cancer. The colonoscopy should take between thirty minutes to an hour depending if tissue samples are taken. During the procedure suspicious lesions can be cauterised with a heated instrument to prevent bleeding. Biopsies of tissue can be taken, and fluid can be extracted and sent to the laboratory for analysis.
There are risks with this procedure as with all, you need to be aware that there is always the slight chance of the bowel being perforated by the colonoscope (the flexible endoscope). There is always the chance of bleeding if a polyp is removed during the procedure, and this can occur up to fourteen days afterwards. If you are regularly taking Aspirin this should be stopped prior to the procedure and you will need to consult your doctor as to exactly how long before the procedure you need to have stopped taking it but it will usually be from 7 -10 days before. You will have been given advice about which medicines you need to stop taking prior to the endoscopy if you have any queries please refer back to your GP. There is also the risk of infection but your doctor will possibly prescribe you antibiotics post procedure if they think it appropriate.
This is the really important part of this procedure as if this is not completed correctly then your colonoscopy may be cancelled and will have to be rescheduled at a later date. This is inconvenient for the doctor and yourself as it will delay diagnosis and treatment. The bowel has to be clear of all faecal matter prior to the day of the procedure, so that the doctor can see the walls of the bowels clearly.
The bowel preparation will consist of either eating a very light diet with no fibre, drinking plenty of fluids to help flush the bowel for three days prior to the investigation and then the day before only drinking clear fluids and taking a strong laxative in the morning and again in the afternoon to help flush any remaining food from the bowel. Remaining near a toilet is very important as the laxative can be strong, maintaining your fluid intake is very important at this point. Alternatively some doctors prefer you to have a fluid only diet for three days prior to the investigation and then a laxative the day before. Check with your surgery if you are unsure.
Fluids you can have include:
- Tea or coffee with no milk
- Clear fruit juice/ cranberry, orange, grapefruit etc but with no bits!
- Soups –clear /strained
The colonoscopy will be done in an endoscopy room, and will be done either by a gastroenterologist (a digestive tract specialist) You will also be looked after by nurses. The procedure will be explained to you before hand so you know exactly what is happening.
- You will be given a gown to change into and your clothes below your waist will need to be removed. You can wear your own dressing gown and slippers until you are taken through to the endoscopy room.
- You will be asked to lie on your left hand side with your knees drawn up slightly towards your chest. You will be covered with a blanket to maintain your dignity.
- A small cannula / needle will be placed in the back of your hand and secured with tape. All intravenous medications will be given through this so you only have the one needle insertion.
- You will be attached to various pieces of monitoring equipment like a blood pressure cuff on your arm, a pulse oximeter which goes on your finger and counts your heart beat and analyses the amount of oxygen circulating your body and ECG electrodes which monitor your heart beat.
- You will be given some medicine to make you feel drowsy and comfortable, you will still be able to co-operate but will have a blurry memory of the procedure.
- The doctor will begin by inserting the endoscope into your rectum and then slowly proceed through your large bowel. You may feel air being blown into your bowel which may make you feel bloated this is to help inflate the bowel to make it clearer for the doctor.
- The procedure is not so much painful as uncomfortable, but the medicine given at the beginning usually makes it tolerable.
- During the procedure you may be asked to move to help the endoscope move more easily through the bowel.
- If you feel that your stomach is cramping taking slow deep breaths can help relax it again
- Biopsies of tissue may be taken for analysis and this may cause slight bleeding. Various instruments can be passed down a channel on the endoscope so the doctor can treat some of the lesions of polyps that they may come across.
When the procedure is over you will be returned to the endoscopy unit to recover. You can eat and drink normally afterwards unless told otherwise.
Results form your biopsies will be sent to your doctor and you will be given a follow up appointment to discuss these.
After the Procedure:
When the affects of the sedative have worn off, it can take up to two hours and you are comfortable you will be discharged. It is important that you have a responsible companion who will stay with you over night and who can drive you home.
At home you may well feel a bit bloated from the air and you may pass a lot of wind this is normal, also you may also have slight bleeding when you first have your bowels open this too is normal. However if you suffer from:
- Stomach cramps that progressively get worse
- A high temperature
Experience heavy bleeding from the rectum
You will need to contact your doctor or the endoscopy unit for advice.
Research has shown that a diet lacking in fruit and vegetables and a sedentary lifestyle with no exercise can increase your chances of bowel cancer. Keeping active and eating well reduces them.