...but he's definitely not quite himself: subdued and less appetite than normal.
He came home yesterday afternoon after doing very well at the emergency vet. (The staff there loves him; the vet says he won't stop purring long enough for her to listen to his heart/lungs.) X-rays taken yesterday morning showed a significant decrease in the fluid in his lungs, and blood tests taken at the same time show his kidney values are elevated but stable compared to those from two weeks ago.
He's on a much, much higher dosage of Lasix, which I suspect is causing him to not feel well because it puts a major strain on the kidneys. After three days, it decreases a bit, and I hope that will help him perk up.
His breathing is fine, he's purring almost constantly, and he snuggled with me a bit last night, which are all good things. He's not interested in his dry food--he'll pick up a piece, mouth it a bit, and then drop it--but he's eating his Fancy Feast canned food with gusto, so his appetite has just gotten more selective, I guess.
The vets at the emergency hospital are very willing to work with me to find ways to get him in there for his blood work and x-rays that won't stress him into another episode of respiratory distress. They're going to let me bring him in a side entrance and go straight to a quiet, cat-only exam room instead of having to bring him in the front entrance and get exposed to all the noise from people, dogs, etc. He has to go back in about two weeks, so we'll see how it works.