Urethral catheterization is a routine medical procedure that facilitates direct drainage of the urinary bladder.
It may be used for diagnostic purposes (to help determine the etiology of various genitourinary conditions) or therapeutically (to relieve urinary retention, instill medication, or provide irrigation). Catheters may be inserted as an in-and-out procedure for immediate drainage, left in with a self-retaining device for short-term drainage (as during surgery), or left indwelling for long-term drainage in patients with chronic urinary retention.
Patients of all ages may require urethral catheterization, but those who are elderly or chronically ill are more likely to require indwelling catheters, which carry their own independent risks.
The basic principles underlying urethral catheterization are gender-neutral (see Urethral Catheterization in Men), but certain aspects of the procedure require particular attention in the female urethra.
The developed female urethra is a 4-cm tubular structure that begins at the bladder neck and terminates at the vaginal vestibule (see the image below). It is a richly vascular spongy cylinder and is designed to provide continence.
Female urinary organs, anterior view.
The female urethra is suspended by the urethropelvic ligament with its 2 sides (the abdominal side being the endopelvic fascia and the vaginal side being the periurethral fascia). The female urethra pierces the pelvic diaphragm and the perineal membrane just posterior to the pubic symphysis. Distally, it exhibits more genital characteristics, becoming rich in glands and developing a squamous epithelium.
For more information about the relevant anatomy, see Female Urethra Anatomy. See also Female Urinary Organ Anatomy and Bladder Anatomy.