What To Do For Lung Cancer?

I am the caregiver for 76 year old man with stage 4 lung cancer, nsc, diagnosed in April. Last xray showed 2 spots on each lobe, all around the size of a quarter. it was originally in his penis, a squamous cell, abd he had a penectomy, and they said this is from that cancer, so I guess it's a met. Unable to take chemo and has a pacemaker, so no radiation. His wight and appetite are up and down, and now he is vomiting atleast once a day and appetite starting ot decrease. I know it's only going to get worse, but what should I look for as far a signs that he's closer to the end, because I recently learned he has a defibulator built in his pacemaker, and I am responsible for making the decision to have it turned off when he is close to death or chance of??