GI Endoscopy and Colonoscopy

• Endoscopy is a medical procedure that allows us to observe the inside of the gastrointestinal tract without performing major surgery.
• An endoscope is a long, flexible tube with a lens at one end and a video camera at the other. The end with the lens is inserted into the cat, and light illuminates the relevant areas and projects it onto the screen. The endoscope can be inserted via the mouth or the anus to assess different regions of the gastrointestinal tract.

Endoscopy of the gastrointestinal tract is used for a few different reasons, but most commonly:

• Taking small samples of tissue for diagnostic purposes (biopsy) e.g. when investigating causes of chronic diarrhoea, chronic vomiting or weight loss
• Locating and sampling tumours
• Locating and removing foreign objects
• Dilating strictures (scar tissue) in the oesophagus, duodenum or colon.

No, endoscopies are generally painless. Compared with the stress experienced by the body in a full surgical procedure, an endoscopy is simple, low-risk and cost-effective. Cats also have a very quick recovery time.

• A limitation of endoscopy is that it cannot examine the entire gastrointestinal tract. It can only examine the oesophagus, stomach, duodenum (the upper part of the small intestine), ileum and colon.
• Some cats have disease only in the parts of the intestine that cannot be accessed endoscopically. Ultrasound or CT imaging helps us determine whether any abnormalities can be accessed endoscopically.
• When biopsies are obtained endoscopically, we take a sample from the inner layer of the intestine, however sometimes the changes are deeper in the tissue and surgical biopsies (which can take a sample from all the layers) is the best way to obtain the diagnosis.
• We will advise you which option we think would be most suitable.

• Typically, your cat is dropped off on the morning of the procedure, or it may have been hospitalised overnight (this is more common with colonoscopies, as more preparation is required to empty the intestinal tract).
• It is important to follow the directions for fasting if your cat has gone home (typically fasting for 12 hours for stomach and upper intestine (upper GI) endoscopy and 24 hours for colonoscopy)
• Your cat will be anaesthetised. If your cat is having a colonoscopy, further preparation of the intestinal tract, such as enemas, may be required.
• The endoscope is then inserted through the mouth or the anus, and the intestinal tract is systematically evaluated. Air is pumped into the intestinal tract by the endoscope to allow visualisation (otherwise, the intestine collapses over the lens, and nothing can be seen).
• Multiple biopsy samples are obtained (they are very small, and the disease can be very patchy in location, so many samples are taken to increase the odds of diagnosing it).
• Any abnormal-looking regions or masses will be biopsied; however, we also biopsy normal-looking tissue, as some diagnoses can only be made based on tissue samples.
• Once the endoscopy is complete, the endoscope is removed, and your cat recovers from the anaesthetic.

Most cats recover without incident from endoscopy. They are monitored for a few hours afterwards and, in most cases, can be discharged later that evening.

Complications are possible but very rare. Sometimes, if a cat has a pre-existing ulcer within the intestinal tract, the presence of the endoscope and/or the air that is pumped into the tract can cause perforation of the ulcer. This is a very serious complication but can be treated, and, luckily, is extremely rare. For cats that we think have an ulcer present, we take special precautions to reduce this risk.

• No, it is often best to keep things exactly the same with cats! However, if your cat is an outdoor cat, they should be kept inside for 24 hours following the anaesthetic.
• In winter, it can be difficult for cats to maintain their body temperature after an anaesthetic, so it’s good to make sure they have somewhere warm.
• Regarding their food, generally their normal diet will be fine, however if we think your cat should eat something different (e.g. as part of a treatment program) we will discuss this with you.

We will phone you with the initial results as soon as your cat has had their procedure. Biopsy results from the laboratory take an additional 48-72 hours, and we will contact you when we have these.