The word urostomy derives from the Greek words ouran (urine) and stoma (opening). A urostomy or urinary diversion is a surgical opening that enables urine to bypass the bladder and urethra. It is performed as a result of bladder cancer, chronic inflammation or neurological dysfunction of the bladder, and malfunctions or defects in kidneys, ureter and urethra. During the procedure, the ureters are cut off from the bladder. Urine flow remains through the ureters and evacuates into a urostomy bag that affixes to the abdomen. The bladder may be left behind or extracted, and the type of stoma ultimately used varies according to the type of procedure.
Before the surgery, the ostomy surgeon should discuss and mark the stoma’s placement. This is a very important step. The ostomy patient must be able to view it and access it as easy as possible. In most cases an ileal conduit is placed below the waist and to the right of the belly button. A colon conduit goes exactly opposite to the left of the belly button.
There are three main urostomy procedures. Their names are associated with that part of the body used to make the stoma.
- Ileal conduit. It consists in the resection of a minor portion of the ileum (small intestine) and its corresponding blood supply. One end of the ressected ileum is attached to the abdominal wall to create a stoma. The other end is sewed shut and then the two ureters are connected to it. This action disables the passage between ureters and bladder. The urine now is made to flow directly from the kidneys through the ileal conduit, to the stoma and finally into a urostomy bag. The remaining part of the small intestine is reconnected and digestive function is restored.
- Colon conduit. It is similar to the ileal conduit, except that the conduit here is made with a segment of the colon. Accordingly, the stoma is bigger than when using the small intestine. The urostomy bag here will have a slightly larger diameter. Aside from this, the mechanics are the same as in the ileal conduit.
- Ureterostomy. It refers to those instances when each ureter is connected directly to the abdominal wall. These create one or two stomas. The former is called a transureteroureterostomy and occurs when the ureters are linked internally and one ureter conforms the stoma requiring only one ostomy bag to collect urine. The latter is called a bilateral ureterostomy and comes about when each ureter is independently brought out onto the abdomen surface thus creating two stomas and requiring two ostomy bags. Bladder function is deactivated as well, but there is no need to use any portion of either the large or small intestine. This procedure is seldom performed.
Once the urostomy is performed, urine flows continuously. The urostomy bag has to be emptied a few times daily, and it is recommended that at night it be attached to a night drainage system. The ostomy bag should be changed according to personal preference, but ideally should not go beyond 3 days.