bedding for old dog with bladder problems

Question
Allie is out 13 year old German Shorthair Pointer.  She is arthritic and has a very leaky bladder.  She has been to the vet several times, I wanted to make sure she didn't have any infections.  I changed her diet for 6 months and that didn't help either.  She is also an outside dog and we live in Missouri.  She has a dog house on our patio.  I keep an electric blanket on for her in the winter and this has worked well for her joints but the blanket was getting wet.  I purchased an leak proof (ha ha) mattress cover, but she seems to root around and so this is not working.  Can you tell me what I can use to keep her warm and dry, or a web site to check into for products that could help us.
Thank you, De P

Answer
Have you discussed Prolin or hormone replacement therapy for her with your vet?  I don't think you can buy them without a prescription.  Our Lab started leaking at abut 12, and the hormones kept her dry the next 3 years she lived.  

I don't have any good ideas on the bedding.  Perhaps look at the baby department somewhere.  I am thinking of a water proof pad with electric blanket under it.  Another idea is a heat lamp above her.  You could give her towels of something washable to sleep on.  Even fresh shredded newspaper every night.  

The last years with an old dog can be very rewarding.  You know you don't have long and treasure them.