I don't have any medical advice, but I do have a prayer that I have posted for two other sick and injured Yorkies.Here is a prayer to St. Francis of Assisi, the lover of all creation, patron saint of animals and the environment, and the founder of the Franciscan Order. It is supposed to be said for 9 consecutive days.
  PRAYER FOR OUR ANIMAL FRIENDS
 
(To make a Novena for a sick pet, say this prayer for 9 consecutive days)
Heavenly Father, the bond we have with our friends of other species is a wonderful and special gift from You. We now ask You to grant our special animal companions your Fatherly care and healing power to take away any suffering they have. They trust in us as we trust in You. Give us, their human friends, new understanding of our responsibilities to these creatures of Yours. Our souls and theirs are on this earth together to share friendship, affection, and caring. Take our heartfelt prayers and bless these ill or suffering animals with healing Light and strength to overcome whatever weakness of body they have:  
(Here mention the names of the animals needing prayer)
Maximus the Yorkie
 
Your goodness is turned upon every living thing; Your grace flows to all Your creatures; Your Light touches each of us with the reflection of Your love. Grant long and healthy lives to our special animal companions. Bless their relationships with us, and if You see fit to take them from us, help us to understand that they are not gone from us but only drawing closer to You. Grant our prayer through the intercession of good St. Francis of Assisi, who honored You through all Your creatures. Empower him to watch over our animal friends until they are safely with You in eternity, where we someday hope to join them in honoring You forever. Amen.