Cystometry

Cystometry is a diagnostic procedure that provides measurable feedback about the function of the bladder. Specifically, cystometry 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 via nerve pathways when it needs emptying. The spinal cord then transmits a message to the bladder to contract and begin the reflex of urinating. A person can override this reflex voluntarily 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 incontinence (inability to control urine flow) or urinary obstruction. Cystometry may be indicated to determine the source of such problems.

Other related procedures that may be used to evaluate bladder or urinary problems include cystography and intravenous pyelogram (IVP). Please see these procedures for additional information.

Reasons for the Procedure

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, but are not limited to, the following:

• Urinary incontinence - involuntary release of urine from the bladder
• Urinary retention - inability to empty the bladder completely
• Neurogenic bladder dysfunction - improper function of the bladder caused by an alteration in the nervous system, such as a spinal cord disease or 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
• Tabes dorsalis - a progressive disorder of the nervous system that involves the spinal cord and causes interference with normal reflexes, such as voluntary urinary control

Your physician may use the results from other procedures, such as cystography and IVP, along with the results of a cystometry procedure to formulate a diagnosis.

There may be other reasons for your physician to recommend cystometry.

Risks of the Procedure

Some complications of cystometry may include, but are not limited to, the following:

• Urinary tract infection
• Autonomic reflex (severe headache, increased blood pressure, lower heart rate, sweating and flushing) in patients who have a spinal cord injury or disease

Cystometry is contraindicated for patients with a urinary tract infection.

There may be other risks depending upon your specific medical condition. Be sure to discuss any concerns with your physician before the procedure.

Straining with urination and certain medications may interfere with a cystometry procedure.

Before the Procedure

• Your physician will explain the procedure to you and offer you the opportunity to ask any questions that you might have about the procedure.
• You may be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully and ask questions if something is not clear.
• Generally, no prior preparation, such as fasting, fluid restriction, or sedation is required.
• If you are pregnant or suspect that you may be pregnant, you should notify your physician.
• Notify your physician if you are sensitive to or are allergic to any medications, latex, tape, and anesthetic agents (local and general).
• Notify your physician of all medications (prescribed and over-the-counter) and herbal supplements that you are taking.
• Notify your physician if you have a history of bleeding disorders or if you are taking any anticoagulant (blood-thinning) medications, aspirin, or other medications that affect blood clotting. It may be necessary for you to stop these medications before the procedure.
• Notify your physician if you suspect that you have a urinary tract infection.
• You may be given an antibiotic a day or so before the procedure.
• Patients who have problems with constipation may be given an enema before the procedure.
• Based upon your medical condition, your physician may request other specific preparation.

During the Procedure

Cystometry may be performed on an outpatient basis or as part of your stay in the hospital. Procedures may vary depending on your condition and your physician’s practices.

Generally, cystometry follows this process:

1. You will be asked to remove your clothing, jewelry, or other objects that may interfere with the procedure.
2. If you are asked to remove clothing, you will be given a gown to wear.
3. You will be asked to empty your bladder. During urination, the amount, flow rate, and voiding pressure will be recorded. Do not strain to urinate as this may alter the test results.
4. You will be positioned on your back on the examination table.
5. A catheter will be inserted into the urethra until it reaches the bladder. You may experience some discomfort during the catheter insertion.
6. 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.
7. A small amount of room-temperature fluid will be injected through the catheter into the bladder. Next, an equal amount of warmed fluid will be injected. You will be asked to describe all sensations, such as warmth, the need to urinate, discomfort or pain, and nausea.
8. The fluid will be drained from the catheter.
9. The catheter will be connected to a measuring device called a cystometer.
10. Fluid or air will be slowly injected through the catheter into the bladder. You will be asked to tell when you first feel the urge to urinate and when you feel that you must urinate. Bladder pressure will be recorded during this time.
11. When the bladder is completely full, you will be asked to empty your bladder while pressure is being recorded.
12. In some situations, medication that can affect the bladder’s muscle tone may be given, and the procedure will be repeated in 20 to 30 minutes.
13. When all tests have been performed, the catheter will be removed. The rectal probe or adhesive patches will also be removed, if used.

After the Procedure

There is no special type of care required after cystography. You may resume your usual diet and activities unless your physician advises you differently.

You will be encouraged to drink extra fluids to dilute the urine and reduce urinary discomfort, such as burning.

You may feel some urinary discomfort, but it should lessen over time. You may be offered a warm sitz bath or a tub bath as a comfort measure.

You may notice blood in your urine for a period of time after the procedure. The amount of blood will reduce gradually over time.

Your physician may prescribe an antibiotic to prevent a urinary tract infection.

Notify your physician to report any of the following:

• Fever and/or chills
• Abdominal pain
• Continued or increased blood in the urine
• Urine output less than usual

Your physician may give you additional or alternate instructions after the procedure depending upon your particular situation.