If the Urine is in the bladder and does not flow, you put a catheter through the urethra.
A urinary catheter is a tube that a nurse would insert into the penis through the urethra to help with urine flow. It is the same catheter, whether to catheterize a male or female. A one-time catheter has no collection bag. An indwelling catheter has long tubing that ends in a collection bag that is hung on the lower side of the bed.
It is quite common for a catheter to be clamped off. Unfortunately not as common as it should be. When this is done the urine will be retained in the bladder. This is not a bad thing -> its what the bladder was designed for. The only problem with this is that if the catheter clamp is left on for an excessive amount of time it may cause pain (like a strong urge to go to the toilet) as the urine collects in the bladder or cause retrograde ureteric flow back to the bladder. One of the problems of NOT clamping a catheter is bladder shrinkage which can lead to urine bypassing (coming out down the sides of the catheter tube) by various mechanisms. bladder shrinkage can be a problem when the catheter is removed.
Catheter urine is more "sanitary" than regular urine. Because it is collected from the bladder, and doesn't "touch" the external skin, it is less prone to skin contamination.
bladder
Catheter
Urinary catheterization is the insertion of a catheter into a patient's bladder. The catheter is used as a conduit to drain urine from the bladder into an attached bag or container.
Urine drainage
Extracellular.
no
Sounds like severe dehydration.
Urine is the catheter tube is "fresher" than urine sitting in the collection bag, often sitting for many hours.