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 (eg, during surgery), or left indwelling for long-term drainage for patients with chronic urinary retention. Patients of all ages may require urethral catheterization, but patients 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, but the specific aspects important in the technique of male catheterization are described in this article. For a procedural description for female patients, see Urethral Catheterization in Women.
The male urethra is a narrow fibromuscular tube that conducts urine and semen from the bladder and ejaculatory ducts, respectively, to the exterior of the body (see the image below). Although the male urethra is a single structure, it is composed of a heterogeneous series of segments: prostatic, membranous, and spongy.
Male urethra and its segments.
Knowledge of male urethral anatomy is essential for all health professionals because urethral catheterization is one of the most commonly performed procedures in health care. The male urethra is susceptible to a variety of pathologic conditions, ranging from traumatic to infectious to neoplastic. Pathophysiologic variants of the urethra may have devastating consequences, such as renal failure and infertility. For more information about the relevant anatomy, see Male Urethra Anatomy.
Prophylactic antibiotics are recommended for patients with prosthetic heart valves, artificial urethral sphincters, or penile implants.
The maximal recommended volume for urethral balloon inflation can be found on the inflation valve (usually, 10-30 mL). See the image below.
Urethral catheter balloon volume indicator.
Diagnostic indications include the following:
Collection of uncontaminated urine specimen
Monitoring of urine output
Imaging of the urinary tract
Therapeutic indications include the following
Acute urinary retention (eg, benign prostatic hypertrophy, blood clots)
Initiation of continuous bladder irrigation
Intermittent decompression for neurogenic bladder
Hygienic care of bedridden patients
Urethral catheterization is contraindicated in the presence of traumatic injury to the lower urinary tract (eg, urethral tear). This condition may be suspected in male patients with a pelvic or straddle-type injury. Signs that increase suspicion for injury are a high-riding or boggy prostate, perineal hematoma, or blood at the meatus. When any of these findings are present in the setting of possible trauma, a retrograde urethrogram should be performed to rule out a urethral tear prior to placing a catheter into the bladder.