Catheters in urology
• Types
• Self-retaining (also known as a Foley,
balloon, or two-way catheter).
• Three-way catheter (also known as an
irrigating catheter).
• Size
:The size of a catheter is denoted by its
circumference in millimeters. This is known as
the “French” or “Charriere” (hence Fr) gauge.
Uses
• 1.
Relief of obstruction (e.g., BOO due to BPE
causing urinary retention).
• 2.
Irrigation of the bladder for clot retention
(use a 20 Fr or 22 Fr threeway catheter).
• 3.
Drainage of urine to allow the bladder to
heal if it has been opened.
• 4.
Prevention of ureteric reflux, maintenance
of a low bladder pressure.
• 5.
To empty the bladder before an operation
on the abdomen or pelvis.
• 6.
Monitoring of urine output postoperatively
or in the critical patient.
• 7.
For delivery of bladder instillations (e.g.,
intravesical chemotherapy orimmunotherapy).
• 8.
To allow identification of the bladder neck
during surgery (e.g., radical prostatectomy).
JJ stents
• These are hollow tubes, with a coil at each
end, which are inserted through the bladder
(usually), into the ureter, and from there into
the renal pelvis.
• JJ stents prevent migration downward (out of
the ureter) or upward (into the ureter). They
are therefore self-retaining.
Indications and uses
• 1•
Relief of obstruction from ureteric stones,
benign (i.e., ischemic) ureteric strictures, or
malignant ureteric strictures. The stent will
relieve the pain caused by obstruction and
reverse renal impairment if present.
• 2•
Prevention of obstruction post-ureteroscopy
• 3•
Passive dilatation of ureter prior to
ureteroscopy.
• 4•
To ensure antegrade flow of urine following
surgery (e.g., pyeloplasty) or injury to ureter.
• 5.
Following endopyelotomy (endopyelotomy
stents have a tapered end from 14 Fr. to 7 Fr.,
to keep the incised ureter open).
Symptoms and complications of
stents
• 1.
Stent symptoms that are common include
suprapubic pain, LUTS (frequency, urgency—
stent irritates trigone), hematuria, and
inability to work.
• 2.
Urinary tract infection.
• 3.
Incorrect placement: too high or too low.
• 4.
Stent migration (up the ureter or down the
ureter and into bladder)
• 5
.Stent blockage.
• 6.
The “forgotten stent is rare, but potentially
very serious, as biofi lm may become
encrusted with stone.
Cystoscopy
• Cycstoscopy is a basic skill of the urologist. It allows
direct visual inspection of the urethra and bladder.
• Indications:
• 1•
Hematuria.
• 2•
Irritative LUTS (marked frequency and urgency)
where intravesical pathology is suspected (e.g.,
carcinoma in situ, bladder stone).
• 3•
For bladder biopsy.
• 4•
Follow-up surveillance of patients with previously
diagnosed and treated bladder cancer.
• 5•
Retrograde insertion of ureteric stents and
removal.
• 6•
Cystoscopic removal of stones.
suprapubic catheterization
• Indications:
• 1.
Suprapubic catheterization is indicated if there
is failed urethral catheterization in urinary
retention.
• 2.
it is the preferred site for long-term catheters.
• Long-term urethral catheters commonly lead to
acquired hypospadias in males (ventral splitting
of glans penis) and patulous urethra in females
Hence, a suprapubic site is preferred for long-
term catheters.
Contraindications
• 1.
Patients with clot retention, the cause of
which may be an underlying bladder cancer.
• 2.
Patients with lower midline incisions (bowel
may be stuck to the deep aspect of the scar,
leading to the potential for bowel
perforation).
• 3.
Pelvic fractures, where the catheter may
inadvertently enter the large pelvic
hematoma.