When urine is stored in the urinary bladder, it allows urination to be controlled and infrequent. During urination, the urine exits the bladder and flows into the urethra, which allows urine to flow out of the body. The normal capacity of the bladder is 400-600 ml of urine.
A sensation of fullness or pressure is experienced when the bladder is full but will disappear once the person urinates. However, some people experience this pressure persistently and sometimes it is accompanied by an ache or pain. This is not normal and may be signs of a distended bladder.
The urinary bladder helps control urination so it does not become too frequent. When the bladder becomes full, the person has to urinate to empty the bladder.
But what if the bladder is unable to empty completely?
When the bladder becomes full and urine stays too long, it may lead to an infection in the bladder or in the ureters. There are cases where the bladder is not able to contract and empty completely. The urinary bladder will become too full and it will swell. The urine may back up into the kidney and the pressure may cause damage to the blood vessels of the kidney. This may cause a distended bladder.
Distended bladder is a term referring to urinary retention in the bladder when it is not capable of emptying normally. It usually occurs when there is a loss of tone in the bladder muscles causing it to fail to detect the elevated pressure exerted by the urine.
In other cases, there is an obstruction that does not allow urine to flow into the urethra. This may cause pain, a feeling of fullness, and the urge to urinate frequently.