INTERNAL AND EXTERNAL URINARY DIVERSION

INTERNAL AND EXTERNAL URINARY DIVERSION

Indications: Diversion of the urine may be either
1-temporary expedient to relieve distal obstruction
2-permanent procedure when the bladder has been removed or has lost normal neurological control and in cases of incurable fistula or irremovable obstruction.
Methods of urinary diversion
=Temporary methods use prosthetic materials, the most common
being
1- urinary catheter. In elderly patients unfit for prostatectomy,and
patients with terminal carcinoma of the prostate, an indwelling silicone urethral Foley catheter changed every 3 months is a satisfactory method of drainage.
2- A suprapubic placement is an alternative to urethral placement. The major drawback of long-term catheterisation is infection secondary to the associated bacteriuria that invariably develops.
3-Ureteric obstruction can be relieved by placement of internal ‘double-J’ pigtail ureteric stents, which can remain for 4–5 months but are usually changed every 3 months.
4-Nephrostomy tube, inserted percutaneously by ultrasound and fluoroscopic imaging, is effective when internal stent placement is not feasible.
=Permanent urinary diversion
a-External diversion
Ileal conduit
Permanent urinary tract diversion is most commonly performed
by conduit diversion. The ureters are implanted into a short,isolated segment of ileum or, less commonly, colon. The conduit diverts the urine onwards to a cutaneous stoma for collection in an ileostomy bag.
Complication:
1-ureteroileal stricture .
2-Stenosis at the ileocutaneous site.
b-Internal urinary diversion
Colon and rectum
The advantage of diverting urine into the colon is that no collecting apparatus is necessary. Clearly, however, the anal sphincter must be competent. Before ureterosigmoidostomy is undertaken, the patient must prove that he or she can control at least 200 ml of fluid in the rectum.