Performing uroflowmetry

What is uroflowmetry? Uroflowmetry is the study of the rate of outflow of urine, its amount and the elapsed time of the ongoing process. This is the simplest urodynamic testing, which provides useful information for establishing the correct diagnosis, followed by the appointment of therapeutic therapy.

Thanks to uroflowmetry, you can test pregnant women, children, the elderly. This research method is completely painless and safe.

What is the purpose of testing

Testing shows delayed or difficult urination. Thanks to the test, it is possible to determine the functionality of the urinary tract and urethral sphincter obturators. The sphincter is the annular muscle tissue, which, when contracted, closes the urethra outlet channel, preventing the outflow of urine.

The test indicators show the interfering processes of the normal flow of urine. When measuring the average, maximum speed of the stream, the form of blockage, obstruction, contractility of the urea, an increase in the size of the prostate gland is established.

One of the types of techniques is radionuclide uroflowmetry. In addition to the above indicators, this method allows you to determine the remainder of urine, urinary and pelvic-vesical refluxes, stenosis of the distal zone of the urinary tract.

Factors influencing urine outflow

Some pathological changes in the body, directly or indirectly, have an effect on the urinary system and the rate of urine outflow:

• hypertrophy (benign) of the prostate overlying the urethra;
• oncological process of the detrusor (cancer);
• malignant process in the prostate gland;
• dysfunction (neurogenic), impaired nervous regulation in a tumor or injury to the brain (spinal cord);
• frequent infection of the urinary tract.

How measurements are taken

Uroflowmetry, how is it done? With the usual delivery of urine for analysis, the patient collects urine in a special container. For UFM, the patient is emptied into a special, funnel-shaped reservoir (specialized urinal) with a built-in measuring device.

For this test, patients must urinate in the same way as in a normal setting, without manipulating the speed or force of the jet. Men do it while standing, women must sit over the device. Some equipped clinics have special chairs.

Thanks to an electronic uroflowmeter connected to a funnel or built-in with an accessory, the velocity and volume of urine are measured. The process of emptying urea begins at the command signal of the laboratory assistant, after turning on the device.

With the help of a uroflowmeter, the quantity of urine that is released by the patient, the rate of its flow in seconds, and the time spent on emptying the urea are recorded. The result looks like a diagram. Normally, it shows a slow onset of urine outflow, further acceleration occurs, by the end of the process, the outflow slows down. Any deviation from the norm is considered a deviation in which the doctor makes a diagnosis. In some cases, a series of measurement tests is used over several days.

Until the uroflowmeter was invented, experts measured the outflow of urine using a measuring container and a stopwatch. The stopwatch recorded the outflow time of the entire process, the volume was measured by the container, then the volume was divided by the time obtained, and the average urine outflow rate was determined.

How to prepare for testing

Before testing, the patient should not go to the toilet for 3-4 hours. The urine container should be full, but overflow should not be allowed. To do this, it is enough to drink 1000 ml of water 30 minutes before the test. The procedure does not bring painful symptoms, but can only cause psychological stress.

Without fail, before taking measurements, patients must inform the specialist:

• the alleged pregnancy;
• taking medications or vitamins;
• the use of medicinal herbs and supplements.

Effective interpretation

Urine flow rate is the volume of fluid during outflow, a quantitative indicator displayed after a certain period of time (per minute or second). Volume is calculated with the letter V, speed - Q, Qmax - flow rate (at minimum). This value serves as a calculus of the degree of obstruction of the pathways of urine excretion with the presence of obstructions in the outflow of urine.

What norms exist

The effectiveness of uroflowmetry indicators depends on age and gender. Men with age have a reduced urine rate, women have less pronounced changes.

On average, urination for males and females should be more than 10 ml per second with a maximum rate of 4 to 9 seconds. From the start of the outflow. More accurate results can be obtained with 350-500 ml of urine, however, cases when testing is carried out on 100 ml of liquid are not excluded.

Healthy people empty urea in 25 seconds. With a reduced outflow time, blockage or weakening of the muscle tissue of the urea is determined, and adenoma can be diagnosed in men. Increased urine flow warns of weakness in muscle tissue that controls the release of urine, suggesting incontinence.

Evaluation of the results is carried out by analyzing the curve of urine emission according to the curvilinear designation. If the patient is doing well, then the graph has a bell-shaped pattern. The narrowed urethra of a man has a graphical plateau appearance. With severe obstruction or a weakened urea contractile process, the graph has a reduced, maximum speed. With detrusor overactivity, a fast set of speed is recorded in the first second of outflow.

Explanation of chart indicators contains a description by specificity:

• obstruction;
• non-obstructive;
• ambiguity;
• swiftness;
• discontinuous.

For example, with an intermittent diagram, urethral stricture is diagnosed, which is associated with jerky contractions of the muscle tissue of the peritoneal wall. At this time, the outflow from the urea is stimulated, due to the pressure inside the peritoneum.

What are the advantages of the technique

With the help of uroflowmetry, a number of pathological processes can be diagnosed with the advantages of testing, namely:

• testing is not independent of the instrumental procedure;
• the risk of infection is excluded during the study;
• repeated tests are allowed to determine the dynamics;
• the ability to quickly, clearly record the results;
• the test can be performed on pregnant women and children.

Contraindications for this test include: vesicovaginal, suprapubic, vesicovaginal fistulas, anomalies of congenital origin.