Colorectal Department Wexham Park Hospital Colonic Stents What is a colonic (bowel) stent? A bowel stent is a mesh shaped to form a thin coiled tube (see illustration below). It is made from a combination of special alloys to enable it to be flexible and durable. It is designed so that, like a spring, it will gently expand once released, creating a cylindrical channel through a narrow area of the bowel. How will it help me? Your doctor may have suggested this treatment because you have a cancer or stricture in the bowel making the bowel narrower and your bowel motions more difficult to pass. By expanding the diameter of the bowel at the point of the narrowing, the bowel should function more easily and be less painful. Once in place, the stent will sit inside your bowel and keep it held open. This may be offered to you as the best way to keep the bowel working when surgery is not recommended or preferred. A stent, as an alternative to an operation, can prevent the need for a general anaesthetic, surgery and the possible need for a stoma (bag). What does it involve? This is a relatively straightforward procedure when performed by an experienced person. The surgeon or endoscopist will first assess if you are suitable for this procedure. They will also discuss what is involved to ensure that you understand. You will be asked to sign a consent form. Please feel free to ask questions at any stage. Before the procedure you may be instructed to take a laxative and/or you may be given an enema to clear the bowel. The stent is inserted either in the endoscopy or x-ray department. Just before the procedure, you may be given a sedative injection to make you feel more relaxed. You may also be given an injection of antibiotics through a needle (cannula) in your hand. A special flexible tube called an endoscope is used to allow the narrowing or blockage to be seen. You will be asked to lie on your left side, allowing the endoscope to be passed more comfortably into your back passage. Then X-rays of the bowel are taken. 2 | Once the correct position for the stent has been found, a thin wire will be gently inserted through the narrowing in your bowel, via or alongside the endoscope. Using the wire as a guide, the stent is then placed inside your bowel. The endoscope and guide wire are then removed. The procedure can take up to an hour. The stent begins to expand as soon as it is released into the bowel. This can feel uncomfortable, but is not usually painful. You may experience some bloating or discomfort in your abdomen. After the procedure After 24 hours you may have an x-ray to check the position and expansion of the stent. You may experience some bleeding from your bowel in the first two days after insertion, but this should stop. The bowel may feel uncomfortable, possibly painful, for up to three days. Please ask for painkillers if you need them. You will be able to go home once the doctors are happy that the stent is in the correct position and that the bowel is working again. If you continue to experience pain, or bleeding persists, please contact your hospital consultant. It may be necessary for you to stay overnight. Are there any risks to this procedure? The main risk from this procedure is perforation of the bowel, which happens in less than five per cent of patients, during stent insertion and stent expansion. A perforation is a split in the bowel lining. If this rare event occurs, it will require surgery under general anaesthetic to remove the damaged part of the bowel. A stoma may be necessary. Occasionally, the stent can become dislodged which will then cause discomfort. If you notice any change in bowel symptoms, let your doctor know promptly. Your doctor will normally be able to remove the stent through your bottom but a quick anaesthetic may be required to remove it. Rarely, a stent may also fall out. In either case, it may be possible to have a new stent inserted. Although most patients cannot feel the stent once correctly positioned, a few patients have reported some degree of discomfort, particularly in the first two weeks after insertion. If you experience ongoing discomfort, bloating and/or bowel spasms, you should seek medical or nursing advice. Results The stent will reach its maximum diameter within 24 hours. It will only stretch as far as the narrowing allows, which may be up to a maximum diameter of 3cm. Your bowel function will therefore be dependent upon the degree of expansion achieved. It generally helps to eat a low fibre diet; as a guide this means eating foods that do not need a lot of chewing. A daily dose of softening laxative may be recommended to help the bowel motions remain loose and easy to pass. Usually 85 per cent of stents are positioned successfully.