My senior dog with bronchitis and liver issues is vomiting weirdly.

Sam certainly sounds like he could be feeling a whole lot better. The contents of the vomit do a look a little odd, sort of grainy and liquefied. It almost looks like he could have gotten into something, or was eating dirt. What kind of medications is Sam taking for his current ailments. Depending on the nature of the liver condition, there are several different medications that should be considered. There is a liver supplement available called Denamarin that is designed to promote liver health and lower increased liver enzymes. I find it very effective in most cases. Depending on the cause of the bronchitis, it may require antibiotics to be resolved or potentially anti-inflammatory medication. If the vomiting is your primary concern at this time, I would give a call to your vet and see if he can prescribe some Cerenia to get it under control. The best thing that can be done would be to get Sam back into the vet to have looked over. With his medical conditions, it would be best to make sure he does not require any hospitalization to get better.