Trixie, my 15-year old cat, has CRF and some form of congestive heart failure. She has had a couple of episodes of pleural effusion that made it difficult for her lungs to breathe. The first time she got a chest stick to remove it, but subsequently when her breathing got bad we gave her an injection of Lasix (20 mg) and that actually seems to get rid of the effusion (which confused the vet -- he didn't think the diuretic should get at the fluid around her lungs).
So the program I'm following now is to give Trixie minimal SubQ fluids for the kidneys/hydration: 25 cc every other day; and to give a Lasix injection if her breathing gets distressed. The last few weeks, that's been every 5-6 days. I'm worried about drastically dehydrating and rehydrating her like that, though. I reduced the injection from 20 mg to 15 to 10 and it still seemed to work, but her weight drops alarmingly each time and it hasn't been going back up all the way. She's a tiny kitty -- was almost 5.5 lb, now she's hovering just above 4.5 lb, and that's scary. I know her appetite has been affected and now I'm assist-feeding so that should help.
My question is, would a regular smaller dose (tablet) of Lasix be more appropriate in this situation? I figure she might need to be kept a little bit dehydrated to control the fluid around her lungs. Should I not be giving the 25 cc SubQ every other day, if I'm giving Lasix? Of course I will ask my vet about this, but I don't really think he knows for sure either.