My poor old pug has been diagnosed with canine dementia and tracheal stenosis.

(please don't tell me about how wrong it is to own pugs, he was a stray I adopted who was found on the street, not a breeder dog I bought. He has a lot of health problems and I've devoted a lot to keeping him well cared for).

My poor old puppy. The restlessness and spinning in circles, the staring off into space, the coughing fits. We are already treating the cough but started some dementia-type medicine and melatonin last night. I don't want to do extensive interventions if he's unhappy but I want to try to improve his quality of life and make his geriatric years as happy and peaceful as possible.

It's so hard to make good decisions about elderly pets isn't it? You want to do the right thing.