Introduction to Colorectal Cancer
With increasing incidence of colorectal cancers in Asia, health authorities are strongly recommending screening at the age of 50 to detect early and surgically curable colorectal cancers. Of all the screening methods, fiberoptic colonoscopy remains the gold standard. It is safe, accurate and well tolerated by patients. It can also be used to excise polyps before they transform into cancers.
Initial consultation is mandatory. During the consultation, the doctor will determine if there are factors that make it unsafe for the patient to undergo screening colonoscopy. These factors include history of heart failure, kidney diseases and previous multiple operations to the abdomen. The patient must also not be allergic to the medicines that will be used for sedation during the colonoscopy.
The patient is then instructed on the following colonoscopy preparation steps:
• Low fiber diet for 3 days
• How to dilute the bowel preparation to clean the colon
• Possible complications of colonoscopy
Once the patient understands the procedure, an informed consent is taken as required by law.
Bowel cleansing (Part of Colonoscopy preparation) solutions come in various forms. The commonest is in the form of two 45 mls bottles of concentrated laxative (Fleet Phospho-Soda). These are diluted into 6 glasses and then consumed over 3-4 hours. Most patients tolerate this very well.
Another preparation called Polyethylene-Glycol (PEG) is used for elderly patients. These are isotonic and more gentle on the cardiovascular system. These come in the form of powder and are diluted into 2 liters and also consumed in 3 hours.
Day of the Colonoscopy Procedure
The procedure is usually scheduled in the morning whenever possible. A glass of water is permitted when the patient wakes up. No milk or solid food is allowed for safety reasons. The patient then reports to the endoscopy center where the nurses will go through a detailed checklist as per protocol. Once in the endoscopy room, a small needle catheter is inserted into a vein on the hand or arm. The attending surgeon will be there to administer the sedatives and will commence the procedure once the patient is comfortably asleep.
The entire produce usually takes 15 to 20 minutes. If there are polyps seen, they will be excised and this may add to the time. Once the procedure is over the patient is transferred to an observation ward and allowed to wake up from sedation. After a period of observation the patient will be discharged home. Some patients even choose to go back to work.
Possible Colonoscopy Complications
Colonoscopy is a very safe procedure in trained hands and complications are extremely rare. The reported ones are:
• Perforation – the chance of this happening is 1 in approximately 8000. This may happen when the surgeon attempts to excise a large polyp in an effort to spare the patient from an operation, and is more likely at the cecum and ascending colon area where the wall is thinner. Should this happen, immediate surgery is arranged to fix the problem and the outcome is usually good.
• Over sedation – patient may run into respiratory difficulties if too much sedation is used. Doses are carefully calculated based on body weight and trained nurses usually monitor the patient closely for early signs of desaturation. As long as patients are carefully monitored this is a very rare complication.
Hence this is why colonoscopy preparation is very important.
Contact us for a consultation and learn more about colonoscopy.