Cystometry is a diagnostic procedure used to identify problems with the filling and emptying of the urinary bladder. The procedure provides information about the muscle function, mechanics and nerve response of the bladder and urinary tract.
A normally functioning bladder sends messages to the brain through nerve pathways when it needs to pass urine. The spinal cord then transmits a message to the bladder to contract and begin the reflex to urinate. A person can voluntarily override this reflex by holding his or her urine. Some medical conditions may interfere with the muscular function or nerve pathways between the bladder and the brain. These conditions may lead to urinary obstruction or urinary incontinence, the loss of bladder control.
Cystometry may be used to determine the source of such problems. It is often administered with uroflowmetry, which provides a measurement of urine speed and volume, and an estimation of post-void residual (urine that remains in the bladder).
Cystometry may be performed as an outpatient procedure or as part of your stay in the hospital. Procedures may vary depending on your condition and your doctor’s practices.
Generally, cystometry follows this process:
- You will be asked to empty your bladder. During urination, the amount, flow rate and voiding pressure will be recorded.
- You will be positioned on your back on the examination table.
- A catheter will be inserted into the urethra until it reaches the bladder. You may experience some discomfort during the catheter insertion.
- An additional catheter or pressure probe may be inserted into the rectum or vagina to measure pressure in the abdomen. Alternately, adhesive electrodes may be placed on either side of the anal opening to measure muscle function.
- A small amount of room temperature fluid will be injected through the catheter into the bladder. Next, an equal amount of fluid will be injected. You will be asked to describe all sensations including warmth, the need to urinate, discomfort or pain and nausea.
- The fluid will be drained from the catheter.
- The catheter will be connected to a cystometer, a tube to measure bladder pressure.
- Fluid or gas will be slowly injected through the catheter into the bladder. You will be asked to say when you feel the urge to urinate and later when you feel that you must urinate. Bladder pressure will be recorded during this time.
- When the bladder is completely full, you will be asked to empty your bladder while pressure is being recorded.
- Medication that can affect the bladder’s muscle may be given in some situations, and the procedure will be repeated in 20 to 30 minutes.
- When all tests have been performed, the catheter will be removed. If used, the rectal probe or adhesive patches will also be removed.
- You may experience discomfort during this procedure including sensations of flushing, sweating, nausea, pain, bladder filling or an urgent need to urinate.
There is no special type of care required after cystometry. You may resume your usual diet and activities unless your doctor advises you differently. You will be encouraged to drink extra fluids to dilute the urine and to reduce urinary discomfort like burning. After the procedure, it’s possible to experience urinary discomfort or notice blood in your urine. This should gradually reduce over time. You may be offered a warm sitz bath or a tub bath as a comfort measure. Your doctor may also prescribe an antibiotic to prevent a urinary tract infection.
Notify your doctor of any:
- Fever and/or chills
- Abdominal pain
- Continued or increased blood in the urine
- Urine output is less than usual amount
Your doctor may give you additional or alternate instructions after the procedure, depending on your particular situation
Cystometry may be recommended to evaluate problems related to the muscle function of the bladder and urethra. Conditions that may cause functional problems of the bladder and urethra may include:
- Urinary incontinence - Loss of bladder control.
- Urinary retention - Inability to empty the bladder completely.
- Neurogenic bladder dysfunction - Improper function of the bladder due to an alteration in the nervous system such as a spinal cord lesion or injury.
- Spinal cord injury
- Multiple sclerosis - An unpredictable disease of the central nervous system that can be relatively benign, disabling or devastating, leaving the patient unable to speak, walk or write.
- Diabetes - A disorder that occurs when the body is not able to use sugar for growth and energy for daily activities.
A progressive disorder of the nervous system that involves the spinal cord and causes interference with normal reflexes such as voluntary urinary control.