The question of whether urine goes into a colostomy bag is a common point of confusion for people learning about ostomy surgery. The direct answer is no; a colostomy bag is designed specifically to collect stool, not urine. This misunderstanding often arises because both colostomy and urostomy procedures involve a surgically created opening, called a stoma, on the abdomen to divert bodily waste. The type of waste collected depends entirely on which internal system has been diverted.
Colostomy vs. Urostomy: Clarifying the Difference
An ostomy is a general term for a procedure that creates a new pathway for waste to exit the body through a stoma. There are three main types of ostomies, addressing separate medical conditions affecting either the digestive or the urinary system.
A colostomy diverts the large intestine (colon) through the stoma, allowing fecal matter (stool) to bypass a diseased or damaged section of the lower digestive tract. The resulting colostomy bag is a receptacle for digestive waste.
In contrast, a urostomy diverts the urinary tract, typically when the bladder is diseased or removed. This procedure redirects the flow of urine to the abdominal wall. The bag worn is called a urostomy pouch, and it collects urine directly from the kidneys via the ureters.
The waste collected by each procedure is fundamentally different—stool for a colostomy and urine for a urostomy. While both involve a pouching system, the internal anatomy rerouted and the waste collected are completely separate.
Anatomy of a Colostomy
A colostomy is created by bringing a section of the large intestine through the abdominal wall to form the stoma. Depending on which part of the colon is used, the stoma is typically located on the left or upper abdomen. The stoma appears as moist, pink, or reddish tissue, similar to the inside of the mouth.
The main function of the colon is to absorb water and electrolytes from digested food remnants. Because of this water absorption, the output from a colostomy is usually semi-formed to solid stool. The pouching system is secured around the stoma to collect these digestive waste products.
The surgical intent of a colostomy is exclusively to provide an alternative exit for fecal matter, bypassing the lower bowel and rectum. The anatomical structures of the urinary system are not involved in the surgical creation of a colostomy.
The Urinary System After Colostomy Surgery
When an individual has a colostomy, their urinary system remains anatomically separate and fully functional. The kidneys continue to filter waste from the blood, producing urine that travels down the ureters and collects in the bladder, just as it did before the colostomy procedure.
Unless a person has undergone a combined procedure to address both the bowel and the bladder, the presence of a colostomy does not affect the process of urination. The bladder stores the urine until it is emptied voluntarily through the urethra. The colostomy and its associated pouching system operate independently of the body’s urinary functions.
In cases where a patient requires a diversion for both systems, two distinct stomas and two separate pouching systems are necessary. For a person with only a colostomy, the urinary system functions normally, with urine exiting the body through the natural urethral opening.