urinary flow rate
Last reviewed 01/2018
Urinary flow rate is simply the volume of urine passed in a certain time. It is usually measured electronically, for which, several types of equipment are available.
Flow rate provides useful information with the advantages of being non-invasive and relatively inexpensive.
Typical maximum values, in ml per second, would be:
- young adult (up to 55 years)
- male 20
- female 18
- over 55 years
- male 12
- female 15
The shape of the curve is also informative:
- in the normal individual, flow rate rises rapidly to a peak which is then maintained until the bladder is nearly empty
- in an individual with outflow obstruction, the curve is prolonged and the maximal flow rate reduced