Flow studies

Your doctor/nurse has requested that you have a test called ‘flows’. This test is simple and requires you to pass urine into a special toilet. Afterwards you will have the lower part of your abdomen (tummy) scanned with a small ultrasound device to see whether you have emptied your bladder fully. This device is not invasive and will not hurt. You will be asked to do the flow test at least twice so you should allow 2 - 4 hours for the test to be completed and expect to be in the hospital for this amount of time.

If you feel you are unable to attend this appointment, please inform the hospital as soon as possible so that the necessary arrangements can be made to re-arrange your test.

Please eat and drink normally to make sure you are hydrated before you come for your test. If possible please arrive with a comfortably full bladder.

Please note: we will be unable to perform your flow test if you have a catheter inserted or a symptomatic urinary tract infection.

Are there any risks associated with these tests?

No, there are no risks associated with flow studies.

What the test involves

Before the test

You will be sent a 3-day bladder diary and quality of life questionnaire by post with your clinic appointment. It is important that you complete the 3-day bladder diary and quality of life questionnaire to the best of your ability. If you do not receive these please call the number on your appointment letter to have another one sent to you. It is important that you bring your bladder diary and quality of life questionnaire with you to the flow clinic. It gives us a lot of information that will help in offering suitable treatments and forming a diagnosis.

During the test

On arrival to the flow clinic, a member of staff will meet you and explain the test fully. You will be asked to drink some water or other fluids to fill your bladder and wait until your bladder is comfortably full before you pass urine. If you arrive with a comfortably full bladder and feel that you need to pass urine then you would be able to do that into the flow meter.

Once you are ready to pass urine you will need to let the member of staff know and they will ask you to urinate, in privacy, into a specially adapted toilet (flowmeter) that will measure how quickly you pass urine. You need to pass urine like you do at home and be as relaxed as possible when you do so.

After passing urine into the flowmeter you will be asked to lie on a couch to have an ultrasound scan of your bladder to see how much urine is left. The scan is performed by placing some warm gel on the skin over your bladder area and moving an ultrasound probe over the skin.

Your urine will also be tested for infection, blood, and other parameters using a ‘dipstick’ and results will be documented in the final report.

This process will normally be repeated two or sometimes three times. This is why the test takes a long time as we have to wait for your bladder to fill each time before you urinate.

After the test

The results will be entered onto our electronic database and the flows scanned to be stored on the electronic patient records.

The results of your flow studies will be sent to the person who referred you for the test; this may be your consultant, GP or continence advisor. Your results will then be reviewed and you may either be sent an appointment to see your doctor or they will write to you with the results and further recommendations.

Patient information

In carrying out our day to day activities, including research, we process and store personal information relating to our service users and we are therefore required to adhere to the requirements of the Data Protection Act 1998 and the General Data Protection Regulation (GDPR), which will apply in the UK from 25 May 2018. Some of your data and results may be used for research purposes but none will have any identifiable information.

We take our responsibilities under these acts very seriously. We ensure the personal information we obtain is held, used, transferred and otherwise processed in accordance with applicable data protection laws and regulations.

Flow Studies Pathway

  1. Referred for flow studies by Doctor or Nurse. Contacted by flows co-ordinator (phone or letter). Flow studies appointment letter sent with bladder diary and quality of life questionnaire
  2. Attend flow study appointment in urology clinic. Test fully explained by a member of staff and bladder diary and quality of life questionnaire collected. Pass urine into flowmeter and have ultrasound scan of bladder – process repeated 2-3 times.
  3. Results from your flow studies will be stored on our electronic database and electronic patient records. Results will also be sent to your referring Doctor or Nurse.

If you or the individual you are caring for need support reading this leaflet please ask a member of staff for advice.

How to contact us:

Flows Coordinator 0117 414 4974

Bristol Urological Institute (BUI)
Southmead Hospital
Southmead Road
Westbury-on-Trym
Bristol BS10 5NB

© North Bristol NHS Trust. This edition published April 2024. Review due August 2027. NBT003109.