Definition

A urine flow test evaluates the speed of urination, or amount voided per second, and the total time of urination.

  Purpose

A urine flow test is utilized to determine bladder function abnormalities, including a narrowed or obstructed urethra (the outflow passage from the bladder) and a weakened bladder muscle (detrusor).

  Description

During a urine flow test, the patient urinates into a uroflowmeter, a funnel-shaped device that reads, measures, and computes the rate and amount of urine flow. The test takes approximately 10 minutes.

  Preparation

The patient is prohibited from urinating at least two hours before the procedure.

Normal results

Average urine flow rates vary depending on age and gender.

Abnormal results

A urine flow test can indicate problems in bladder function, such as an obstruction, that will need further tests to diagnose.

   Key Terms:

Detrusor muscle Bladder muscle. Urethra Passageway that carries urine from the bladder.

   Resources:

Books

• Pagana, Kathleen Deska. Mosby's Manual of Diagnostic and Laboratory Tests. St. Louis: Mosby, Inc., 1998.
• Walsh, Patrick C., et al., ed. Campbell's Urology. Philadelphia: W. B. Saunders Co., 1998.