Going to the Bathroom

 When your dog becomes paralyzed and loses the ability to control their bladder, it is extremely important that you learn how to express their bladder. ( If they still have control over their bladder, this is not necessary. )    Your regular vet can show you how to do this.  We will provide a few links below as well with instructions.  
The reason it is important to learn to express the bladder if your dog can not control their bladder muscles is to help them to completely empty their bladder.  Not only does this help prevent accidents, but it also helps clear out the bladder to help minimize the risk for bladder and urinary tract infections. Remember the bladder, kidneys and urinary tract are all part of the system that eliminates waste. If the waste sits too long it can cause an infection.  Nature does work it's course and what goes in does go out, but if a urinary tract infection (UTI) is not treated quickly and properly it can continue to get worse. It is important that your vet cultures the urine sample if the urine smells a little funky, or strong, or is deep yellow, orange or even red and looks like blood. By culturing the urine sample they should prescribe the proper antibiotic. Some vets don't do this and the UTI comes back and is usually more fierce. It can settle in the bladder too and get deep into the tissue.  The right antibiotics are key for this. Even if you see what looks like pure blood coming out - it can be treated, so don't get scared, just make sure you get your dog to the vet.  (If you are not comfortable with your own vet, or are afraid someone is going to suggest putting them down because of the UTI - make an appointment with a veterinary specialist who focuses on Internal medicine - they will know exactly what to do to help.  
UTI's are very common with paralyzed dogs, so be aware that you'll probably see this happen at some point, and it's relatively easy to fix or control once you get it properly cultured, and treated.  You also can work with a holistic vet who is trained in food therapy and herbs, on top of regular veterinary medicine, and they can help you alter the body chemistry of your dog through diet to make it inhospitable to bladder infections and urinary tract infections.
Below is some information that will be helpful.  Sometimes it's a challenge at first but once you figure it out it's easy.  If they are resisting, they have some bladder control - and this is a good thing - Ask your vet to show you how to do this too - so you have someone to show you with your own pup.

How to Express a Dog's Bladder

How to manually express a dog's bladder demonstrated by Margaret, a Veterinary Neurology Technician

Expressing a bladder of a pup with lower disk disease

 Basic video showing you how to express a bladder on a dog with disc disease & related information 

Expressing the Bladder of a Paralyzed dog

This is a demonstration of another method to express the bladder of a paralyzed pup while laying down.     

" Omid's bladder gets expressed several times a day.  This video shows you  how we do it, when he is inside the house, we do this before putting on  a new diaper. By doing this, you help the dog to remain clean in his  diaper for a longer period of time and more importantly, when getting  all the urine out of a paralyzed dogs bladder, you decrease/eliminate  the chances of infections "