How long does it take Lasix to work?

Hi:  I have a beautiful 7 year old domestic short hair who was diagnosed a few years ago with a level 1 heart murmur and no other symptoms.  She has just been diagnosed with congestive heart failure.

I have a couple of questions:

First, I only noticed the symptoms after she had (elective--I'm an idiot) dental work where she was anesthetized. She had no symptoms prior to this. Is it possible that the anesthesia pushed her into heart failure?

Second, she was hospitalized yesterday and put on lasix shots, then put on a continuous lasix drip last night, spent the night in an oxygen tent, and is peeing, but there is no clear improvement. She is still breathing rapidly. It's been less than 24 hours but how long does it take for the lasix to make a difference?

thanks.

Each case is different and in my cats case he was ok in a few hours but CHF was due to cardiomyapathy but he didn't have surgery. He has to pee out all the fluids so it may take a while.

It's not just the anesthesia but the fluids they give to support blood pressure that can push an at risk cat into CHF.

Hopefully you can get him through this and once he's out of crisis you may want to discuss with your vet giving him an echo and having a cardiologist evaluate the cause of his murmur.
Also since Lasix puts cats at risk for kidney failure, I would discuss having blood and urine samples taken after this to check his kidneys.

Sending vibes!
Stephen

Thank you so much for the reply and vibes.  She's got a good cardiologist and he said it is cardiomyopathy that caused the chf.  I guess I just have to be patient and hope for the best.

Monica

OK I wish you and your cat the best.  Once you're through this you can ask your cat's cardiologist how to time your cat's breathing when at rest to detect early chf should it reoccur.  You can also request an emergency does of lasix in a syringe if you are ok giving a sub Q injection (actually quite easy and they can teach you).  This way if there is an emergency and it will take you a while to get to a vet you can begin treatment right away.

Stephen

Doctor called this morning and said her lungs were much clearer! Yay!  Thank you for the great advice.  I'll ask about timing breathing and lasix injection. 

Monica

Great news, congrats!  Very happy for you.

stephen