Urinary catherization Flashcards
How long is the male urethra, and what are its four parts?
The male urethra is approximately 18-22 cm long and consists of four parts:
- Pre-prostatic urethra (1-1.5 cm) – from the bladder neck to the prostate.
- Prostatic urethra (3-4 cm) – traverses the prostate gland.
- Membranous urethra (1-2 cm) – narrowest part, passing through the external urethral sphincter.
- Spongy (penile) urethra (15 cm) – extends from the sphincter to the external urethral meatus.
What is the narrowest part of the male urethra?
The membranous urethra (1-2 cm) is the narrowest part, passing through the external urethral sphincter.
What structure in the male urethra can cause resistance during catheterisation?
The external urethral sphincter, which is under voluntary control, can cause resistance during catheterisation.
Why is the bulbar urethra clinically significant during catheterisation?
The bulbar urethra is prone to trauma and the formation of false passages, making careful catheterisation important.
How long is the female urethra, and what is its anatomical course?
The female urethra is 4-6 cm long. It extends from the bladder neck to the external urethral meatus, which is located anterior to the vaginal opening.
Why is catheterisation generally easier in females than in males?
The female urethra is shorter (4-6 cm) and has less resistance compared to the male urethra.
What is a key risk during female urethral catheterisation?
The proximity to the vaginal canal increases the risk of contamination during catheterisation.
What are three major reasons for urethral catheterisation due to urinary retention?
Acute urinary retention (e.g., benign prostatic hyperplasia, urethral stricture, neurological disorders).
Chronic urinary retention (e.g., neurogenic bladder in spinal cord injuries).
Bladder decompression (e.g., pre- or post-surgical procedures, obstructive uropathy).
Why might a catheter be required after a transurethral resection of the prostate (TURP)?
Continuous bladder irrigation is needed after TURP to prevent clot retention.
In what cases might urethral catheterisation be used to manage urinary incontinence?
In severe immobility or neurological conditions where other methods are not feasible.
Why is a urethral catheter used in critically ill patients?
To monitor urine output accurately in intensive care unit (ICU) patients.
When is a catheter necessary for urine sample collection?
When a sterile urine sample is needed for culture and sensitivity in patients unable to provide a clean catch sample.
What studies might require urethral catheterisation for bladder function assessment?
Urodynamic studies to evaluate bladder function.
What radiological studies may require urethral catheterisation?
Retrograde urethrogram and cystourethrography for imaging the urinary tract.
What is a Foley catheter, and what is its main feature?
A Foley catheter is an indwelling catheter with an inflatable balloon to keep it in place
When is an intermittent (in-and-out) catheter used?
It is used for single-use drainage and then removed.
What is a Coude (Tiemann) catheter, and when is it used?
It has a curved tip and is useful for navigating around prostatic enlargement.
What is a three-way catheter used for?
It is used for continuous bladder irrigation (CBI), typically post-TURP (transurethral resection of the prostate).
How is catheter size measured, and what does one French (Fr) unit equal in millimeters?
Catheter size is measured in French (Fr) units, where 1 Fr = 0.33 mm in diameter.
What are the recommended catheter sizes for children?
6-10 Fr
What are the recommended catheter sizes for adult females?
12-14 Fr
What are the recommended catheter sizes for adult males?
14-16 Fr for routine use, 18-20 Fr for gross hematuria or clots.
What size catheter is used for continuous bladder irrigation (CBI)?
20-24 Fr
What is a single-lumen catheter used for?
It is used for intermittent catheterization.
