Purpose: A colonoscopy is recommended in the following cases:
- To find out the possible causes of intestinal symptoms
- To screen for colon cancer in the case of people who are 50 years or older
- To look for and remove polyps (abnormal growth of tissue on a mucous membrane), which reduces the risk of colon cancer
Symptoms: The following lower gastrointestinal symptoms may indicate the need for a colonoscopy:
- Stomach pain
- Bleeding from rectum
- Chronic or long-term diarrhea
- Chronic or long-term constipation
- Bloody stools
- Black, tarry stools
- Unexplained loss of weight
Cleansing the bowel is needed for a successful colonoscopy. This can be done in the following ways:
- Changes in diet: Certain dietary changes are recommended the day before the procedure, like eating a light breakfast and lunch and skipping dinner, or consumption of a liquid-only diet.
- Consumption of only clear liquids: The doctor may recommend drinking only clear liquids, like broth, water, tea or coffee without milk the day before the procedure.
- Laxatives: The doctor may recommend taking laxatives a day before the procedure, either in liquid or pill form. Sometimes, it may be necessary to take them on the morning of colonoscopy.
- Enemas: An enema kit may be used the night before or a few hours before the procedure.
- Tell your doctor about any medications that you may be taking, especially if you are suffering from heart problems, high blood pressure, or diabetes.
- Tell the doctor if you are taking any supplements or medications containing iron.
- The doctor may recommend stopping blood-thinning medications like warfarin and aspirin a few days before the procedure. The doctor may also recommend an adjustment in the doses or stopping other medications that you may be taking.
Procedure:
- The procedure is usually performed on an outpatient basis, that is, the patient goes home on the same day of the procedure.
- The patient lies on the left side and the knees are pulled up to the chest during the procedure.
- The procedure is performed under a light sedative, which makes the patient drowsy and relaxed, and a pain-relieving medication.
- In some cases, deeper sedation or anesthesia may be used.
- The doctor gently inserts the colonoscope through the anus into the rectum and colon.
- The image obtained is transmitted onto a video screen.
- The doctor then inserts air or carbon dioxide into the colon to inflate it and give a better view of the intestinal lining.
- The stools and fluids are removed through the colonoscope as required.
- The doctor then slowly and gently pulls out the colonoscope from the colon and rectum and examines it for any abnormalities.
- The doctor may perform other procedures like tissue biopsy (the removal of a sample of abnormal tissue growth and sending it to the laboratory for evaluation) during colonoscopy.
- The procedure takes half an hour to one hour to complete.
The following risks are associated with colonoscopy:
- Allergic reaction to the medications or sedative used
- Bleeding
- Infection
- Dehydration
- Puncture of the large intestine
- Nausea
- Vomiting
- Rectal discomfort
- It takes approximately an hour before the patient begins to recover from the effect of the sedative after colonoscopy.
- It takes up to a day to completely recover from the effect of the sedative.
- Avoid driving or going to work for the day after the procedure.
- If the doctor removes a polyp during colonoscopy, the patient will be advised to eat a special diet temporarily.
- It is normal for the patient to feel bloated or pass gas for some hours after the procedure, as the air from the colon is cleared.
- Walking may help in relieving patient discomfort.
- It is normal to notice a small amount of blood in the first bowel movement following a colonoscopy examination.
- The patient should consult the doctor if he/she continues to pass blood, has a fever, or has abdominal pain.