If he's been vomiting for 5 days and not improving, he needs immediate medical intervention! Unfortunately, I've seen multiple different foreign bodies from dogs that have ingested couch cushions, as well as a bunch of other things. The ones I've personally seen that have ingested cushion -- the cushion stuff tends to expand with the water and stomach acid, often causing an obstruction. Typically, these individuals need surgery to get the stuffing out. It is also possible something else is going on with Duke, if he only chewed up the cushion and didn't ingest any of it. The place to start would be a full physical examination. Your vet will likely want to run some blood work (CBC, Chemistry panel, maybe a pancreatitis test, or lactate level), abdominal x-rays, and possibly other tests. If he hasn't been abel to keep anything down for 5 days, he is likely also dehydrated and with the vomiting, his electrolytes may be out of balance. I recommend you phone your vet and have Duke seen on an emergency basis.
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