Urinary diversion procedure is required when the bladder is compromised due to cancer or spinal cord injury (leading to a neurogenic type of bladder) or if it is irreparably damaged due to trauma. In this procedure an artificial urinary diversion is created to divert the urine either to an external pouch or internally into the intestine.
Ileal conduit is the most commonly done diversion procedure, whereas 'Cutaneous Ureterostomy' is less common and has been used in infants and children when they have congenital defects of the bladder.
One or both ureters are detached from the bladder. They are brought through a new opening made on the abdominal wall or into a section of small intestine and the intestine is brought onto the abdominal wall. The urine collects into the stoma pouch that is fitted snugly against the abdomen with the help of a belt.
For creating an ileal conduit, the ileum section of small intestine is used to create the pouch.
The urinary tract comprises the kidneys, ureters, the bladder and the urethra. The kidneys filter the circulating blood to remove unwanted materials. The two kidneys present in the body filter about 120 to 150 liters of blood every day and produce up to 2 liters of urine per day.
The ureters are thin tubes coming out of each kidney and carry the urine to the urinary bladder. Urine is stored in the bladder until it is full and the brain receives a signal to void.
The bladder is a hollow organ that is located in the lower section of the abdomen and has a capacity of about 400 mls. The bladder essentially has two important functions:
Urine is voided from the bladder through a tube called urethra, located at the bottom of the bladder. When ureterostomy is done, the bladder and the urethra are bypassed.
Cancer of Bladder
The usual cancer of the bladder is called transitional cell carcinoma and if the cancer is superficial, it indicates a good prognosis and the chances of survival are high. However if it is deep and invasive, then the survival rate declines and hence removal of bladder and a urinary diversion or an artificial bladder may need to be created.
Neurogenic Bladder
Neurogenic bladders are abnormal bladders where either the sensation to empty is lacking or the whole voiding mechanism is un-coordinated. Some of these bladder contracts or becomes overactive even when resting and not full for voiding.
The filling and voiding mechanism of the bladder are controlled by the brain through nerves that pass down from the brain via the spinal cord and supply the bladder. One set of nerves takes the sensation of bladder fullness to the brain and another set from the brain commands the bladder to empty. When these nerves are either deficient or get damaged it leads to the condition called neurogenic bladder.
Neurogenic bladder cannot only give symptoms of urgency and incontinence but also can damage the kidney due to high pressures within the bladder that get transmitted to the kidneys. Urinary diversion procedures in such situations are done to protect the kidneys from these abnormal bladders.
Recently at Wake Forest Research Centre in the USA, Neo bladder from 'Tissue Engineering' has been created to replace such diseased bladders.
There are a number of causes that lead to 'Neurogenic bladder'. Some babies are born with problems of the spinal cord, such as spina bifida and these lead to abnormal bladder. The average incidence of spina bifida is 1 case per 1000 births in most countries. Other conditions that lead to neurogenic bladder include:
Opening Brought Out to the Skin
Opening Diverted to the Bowel or Intestine
Uretero-colic Diversion
To the Urethra
Orthotopic Neo bladder
Opening Brought Out to the Skin
Urostomy stoma can be done in two types of procedures - ileal conduit and cutaneous stoma.
Ileal Conduit: A short segment of the small intestine is taken away, while the remaining of the small intestine is reconnected to function normally. The removed segment is placed in such a way that it connects kidneys to a stoma on the skin surface via the ureters.
A temporary fine tube called urostomy stents are inserted into each kidney via the ureters to allow free drainage of the urine from the kidney into the small intestine conduit or stoma bag.
The urine now travels directly from the kidneys through the newly formed passageway through the stoma to an external collecting pouch. The pouch is fixed externally on the skin and can be drained into a toilet without disconnecting it from the stoma.
Cutaneous Ureterostomy: The ureters are detached from the bladder and the opening is brought to the surface of the abdomen. A stoma, or opening, is created at the point and an external pouch is fitted at the stoma.
Cutaneous ureterostomy can be done in four ways. Single ureterostomy is a procedure in which only one ureter is brought to the surface of the abdomen. When the two ureters are brought to the surface of the abdomen, one on each side of the abdomen, the procedure is called bilateral ureterostomy.
Double-barrel ureterostomy involves bringing together both the ureters to the same side of the abdominal surface, through two different stomas.
The pouch needs to be emptied when it is filled to about one-third to one-half. During night, a piece of flexible tubing can be attached to the draining valve to empty into a bigger pouch, so that the patient is not disturbed during their sleep.
The Ureterostomy Stoma is moist and red and produces mucus as it is a part of the bowel that is modified. It does not have any sensation as there are no nerve endings, but has rich blood supply. The stoma may seem to move sometimes, but this is not a cause of concern. It is in response to the normal contractile movement of the bowel that directs the urine towards the urostomy pouch.
The Urinary Pouch or bag called a urostomy bag is made of a plastic substance and it is fitted on to the ileal conduit or cutaneous ureterostomy. The pouch system consists of two parts.
Sometimes the two units are fused into one. The barrier keeps away the urine from the skin and is designed to be skin-friendly. The pouch is connected to the barrier and has a draining valve at the bottom. The draining valve helps the patient to empty the urine into a toilet without removing the pouch from the stoma.
A one-piece pouch comprises of a pouch with the adhesive directly on to it, and can be left on the skin for 1 to 3 days before it is changed. A two-piece pouch system has a flange for the skin barrier, which is fitted to the abdomen around the stoma, and the pouch is fitted into the flange. This type of pouch can be retained for about 3 to 5 days.
The urostomy pouch is available in shops selling surgical goods, under several brand names. All pouches are made of water-proof and skin friendly materials and are odor-proof. The valve that collects the urine is usually a one-way valve that prevents the urine in the pouch from flowing back to the stoma. The valve that drains out urine is fitted at the bottom of the pouch.
Special diversion procedures called continent urinary diversion can be performed but these are more complicated to perform and sometimes can have higher early surgical complication rate. In this procedure, the surgeon creates an internal reservoir from a section of the intestine, and connects the ureters into this reservoir once it is ready. The patient can drain the urine collected in the reservoir pouch using a small tube. The urine will need to be drained 4 to 5 times a day with these catheters. This procedure does not require wearing an external pouch to drain the urine.
Continent urinary diversion can be done in two ways:
This is an internal diversion to where the ureters are diverted to the large intestine such as sigmoid colon and urine gets mixed up with feces. This procedure does not require care of the external stoma and is sometimes the preferred procedure in children born with bladder abnormality such as extrophy of the bladder or when there is a cancer of the bladder such as rhabadomyosarcoma. It is also the preferred method in a less affordable patient, where the costs of the external appliances need to be avoided. The disadvantage of the procedure is that there is a risk of infections of the kidneys and salt imbalance due to absorption from the intestine.
Patients who are advised to go for urinary diversion procedures will have to undergo diagnostic procedures:
After the surgical procedure, it is very important to take care of the stoma. This is because, the stoma is directly connected to the kidney through the ureters and all these organs are exposed to infections.
There are specially trained nurses and para-medical staff who can train a person in how to use the urostomy bag and work as a support staff. There are also support groups that can help.
A WOC nurse (Wound, Ostomy and Continence nurse) advices and helps the patients to take care of the wound, stoma and the pouch. Entero-stomal therapists counsel the patients regarding ostomy care and rehabilitation.
Postoperative Care after Urinary Diversion Procedures - Taking care of the stoma:
Any continent or non-continent stoma requires basic daily care to keep the skin surrounding the stoma healthy and clean. Cleaning can be done in the following ways:
Taking Care of the Pouch:
Care for Continent Cutaneous Reservoir:
General Care after Urinary Diversion:
Bacterial infection is one of the post-operative risks of urinary diversion ureterostomy. Symptoms like fever, milky urine, strong-smelling urine and urine containing excessive mucus, must be looked into and further investigations must be carried out.
