How a feeding tube is replaced depends on the type of tube you currently have. If it is a tube with a rubber or plastic "bumper" inside the stomach, it is generally removed and replaced using the same procedure as it was put in with. This means having an endoscopic tube inserted down your throat which is done under light anesthesia. It will not be painful afterward because the same track through the abdomen will be used.
If the tube is held in the stomach with a small balloon, the balloon is simply deflated and the tube slides out. The new tube is put in through the same track. A Mic-Key tube is no different than any other balloon tube, just shorter on the outside.
If you don't know which type of tube you have, a bumper type will have only one or two capped ports to put the formula through. (The second is a medication port but most often medications are put through the feeding port)
A balloon tube will have a third port that doesn't have a cap. A 5 or 10-cc threaded tip syringe is screwed into it to inflate or deflate the balloon. A balloon tube has to be replaced about every six months because stomach acids cause the balloon to deteriorate and the tube falls out easily. The procedure is fast, easy, and painless and can be done by experienced caregivers at home.
A bumper tube needs infrequent changes. Some doctors want it changed every 18 months, others don't change them unless they have leaks or are hopelessly plugged. They can be left in for several years. Because an endoscopy tube needs to be used, light anesthesia is necessary, but the same track through the abdomen is used so it isn't painful afterward.