I wanted to share some information about Fading Puppy syndrome and a good outcome. It is not a syndrome so much as a description of a condition in which and otherwise healthy puppy just declines and eventually dies. This typically will occur between 5 and 18 days post partum. The puppy may have been thriving and growing and showed no signs of distress. There are a variety of causal factors that make this situation occur and most likely you will not know what they are.
I recently had this occur and got the baby to live so I wanted to share what happened. I had a small (under the death line of 8 ounces for a large breed puppy to survive) 7 oz puppy born otherwise healthy and thriving. She nursed well, slept well, no excessive crying and was gaining an ounce a day - carefully monitored. At birth (we suspect she was not a runt, but rather her egg was fertilized days later than the rest of the gang - her milestones; pigmentation, suckle response, size indications all date her about 4-5 days younger than the group) she couldn't suckle well, so we did feed her with a syringe sans needle. This must be done carefully and is a topic of discussion all its own - you can drown a baby fast not knowing what you are doing. She did however nurse before the first 24 hours were up - so she did get the ever important colostrum. She did well for 8 days and was vigorous and healthy, but out of nowhere on the evening of the 8th day was lethargic and couldn't hold her head up let alone nurse.
I knew this was fading puppy, but didn't know what to do. There are a variety of sources out there, but no one gave real particulars so I thought I'd share mine. These babies need three things to survive; heat, hydration, and blood sugar. Without any one of the three - they won't make it. We had kangaroo held her when she was so little thinking her much like a preemie. To do this you put their belly on your skin - in my case, my less than ample cleavage and a hand over the top. We always warmed her first (feeding a cold baby will absolutely kill it!). Five minutes seemed to do it. She was not isolated by the DAm, but was isolated sometimes out of the group moving and her not being able to. Once we knew her to be warm, we fed our formula of glucose. I did one part Kar0 syrup to 5 parts water. She didn't even want it, but I could get at least her swallow reflex by gently rubbing her throat. I was feeding with a tenth of a ml diabetic type syringe - bigger and you'll choke them. It wasn't volume I was after - it was vigor. Several drops and then more kangaroo. It did seem to give her energy enough to drink more in 5 minutes. Then I was after a bit of volume. I got no more than .6ML into her - more kangaroo. She needed my warmth to digest and I needed to feel like I was doing something (think the heartbeat helps too!) I then rested her with the pile of puppies making sure she was not trapped under someone and that her head was open to air. An hour later, more glucose (this needs to be warmed to blood temperature - 4 secs in a microwave for me, stirred with my clean finger to test). We did several glucose only feedings until she could hold her head up. Her stomach was less wrinkly and I checked her urine which was becoming lighter. We knew we had hydration and we always had heat, now we needed to get the glucose/milk replacer to revive her. I offered her a nipple 5 minutes after glucose feedings, but she never would take it.
Finally I did a glucose feeding, with kangaroo holding 5 minutes waiting for the energy and then offered the ml (one size up) suction stopper syringe needle removed filled with warm puppy milk replacer. She took it. Slowly at first and always wary of her choking. I'll bet she yawned a million times and we'd have to stop. Then start again because she was used to sucking in a pliable nipple, not have me slowly droppering it out to her with the pusher. I cradled her head with my finger to keep us all at the same pace and used that hand's thumb to stroke her throat to encourage swallowing. At times she'd fall asleep and I'd rub her a bit. I was aiming for 5 ml of milk (one tsp: for a lg breed at 14 oz or so she needed at least two tbl a day - so I aimed for a tsp every two hours, knowing we were spilling some too). I would do glucose alternately before the milk offer every 2 hours just to make sure she was getting needed energy calories. About 20 hours into it all, she was strong enough to nurse!!! Wow a breakthrough and the first sign I had that she would survive. I still kangaroo held a lot. My preference was always to get her to nurse first. I protected her nursing from siblings who were much more adept at feeding. I tried to save her 'hind titt' which has the best supply seemingly. I would now only do glucose every ten hours and would bottle feed if I felt like she wasn't getting enough nursing or was tiring too quickly. She was now eager when I fed her milk. Soon enough, I wasn't needing to 'plug her in' every time I went to check, she was nursing on her own. By 48 hours after the first sign of lethargy, she was back to normal. The only thing I didn't have or do was oxygen, which I hear is helpful. You have to devise an oxygen mask. In desperate situations where you are losing a litter to this problem - it is more indicative of a disease or infection. I saw in my searches on the internet where those situations are often helped by taking and adult who has recently been innoculated and having blood drawn. The Vet then spins it to remove plasma. The plasma is injected intravenously to the affected puppies and within hours are better again. There are so many causes, but no matter if you keep the three vitals safe - I think you can get a fair chance. Heat, hydration and blood glucose. When I searched on the internet, no one had good endings. Its a lot of work - but OH! so worth it!