I know this was posted nearly two years ago, but if anyone comes across this trying to find something, maybe it will give them a bit of extra information and hope for their little one.
I live in Adelaide, about 45min from the city centre and it's pretty bushy in my area, and we have had brown snakes in our yard before, so close to nearly biting one of my other cats once. Anyway, my cat Gigi, was acting strange when I got home Tuesday afternoon, she was fine in the morning and came in and slept in with me on my pillow. She was fine at first, but within half an hour was limp and couldn't move, and stopped breathing a few times. We took her to the Emergency Centre in Adelaide, 45min drive, she pooed all over my blanket in the car, and just got worse from then on. The vet didn't do any blood checks, she told us it was definitely a snake bite, and that antivenin would cost us $1400, and then hospitalisation could be another $1000 depending on how long her first stage recovery would be. But there were also risks because she could have an allergic reaction, but they could give her something to try and prevent that. I love my cat, but I just don't have that kinda spare cash lying around. So the vet gave her under the skin fluids, charged us a heck of a lot, and sent us on our way.
I gave up my bed for her, and my blankets, gave her a hot water bottle, and let her rest. Waking up every 2 hours just to check on her to make sure she was okay, not overheated, not too cold and so on. Wednesday she didn't do much, except pee in the bed. Thursday she wasn't much better, and I called back the Emergency Centre asking what I should do about hydrating her. They told me she would need fluids that day, and at the latest Friday morning (she couldn't swallow as she was nearly completely paralyzed). And told me to call my local vet, and ask them to show me how to give her IV fluids so that I could administer them myself (knowing that I was low on funds and couldn't afford to take her in overnight for direct IV).
I called 5 local vets, and only one of them was willing to show me how to do it. So I went in on Thursday afternoon, and the girls there were absolutely wonderful! They explained to me exactly how the venom was affecting her, and that she had an irregular heartbeat which was bad (they were truthful, and it felt like the other vet withheld some of the more unpleasant information, which is understandable, but I do want to know exactly what it happening and understand it all, it helps me deal with it). They showed me how to hook up a bag of Sodium Lactate IV fluids, what the bits and pieces were called, where to inject her, how to hold the skin and anything else I needed to know (also that she needed 200ml of fluids a day). They gave me extra bits and pieces to take home, and suggested a can of supplement food with necessary vitamins to help her immune system when she started eating (which was surprisingly cheap).
I'm so glad that they gave me the IV bag and showed me how to do it, since I didn't have to worry about her getting dehydrated. And the fluid bag also has salts and sugars in it, and sugar is needed to help the kidney function and repair itself. By Friday I had managed to get Gigi to eat some food. She absolutely hated the supplement, and I had to mix it with tuna to encourage her to eat. She was having trouble, but she could definitely swallow now, which she couldn't do at all before, and left dribble marks all over my pillow!
By Saturday she started walking, only taking 4-5 steps and then lying down for a bit. I went outside with her for a while (she's an outdoor kitty and loves it) and sat with her. She was eating okay by then (still disgusted by the supplement food) and drinking some cat's milk I bought for her as a treat. It's now Sunday night, and she spent most of the day outside. She still has a slight limp in her back left leg, but as much as I try I can not get her to sit still. She's even started hunting mice again, and just caught a mouse and ate it a few minutes ago.
She's still got a way to go, as her heartbeat is still a little fast and pretty irregular, her breathing isn't quite right yet, and her muscles need to repair themselves. I'm actually very surprised she started walking and eating as soon as she did, as the vets said she could take up to another week before she started moving (the venom is still active in the system for about a week after they've been bitten). It must have been a warning bite, as neither of the vets could find a clear bite mark, but she is also a very fluffy cat, so if it was small it's easily missed, so there must not have been that much venom in her system.
To sum it all up, I was in hysterics when she started acting the way she did, and was even more upset when I found out it was a snake bite and that there was nothing I could really do. I've been with her for nearly 10 years now and I couldn't bear the thought of losing her! I found very little online about caring for a cat with a snake bite, as everyone always says "Take it to a vet immediately"! This was the only forum I found, and I'm so glad your cat made it! If anyone comes on here looking for some suggestions, the main one would be KEEP THEM WARM! They can't regulate their own temperatures, and I found that when Gigi had rolled away from the hot water bottle, she was really cold and her breathing got worse. I was told that a cat's ideal temperature should be 37.5-38C. And also if you can, get some under the skin fluids if you can't afford hospitalisation. Depending on how much they inject, it can keep them hydrated for a maximum of 24 hours (is what I was told by the vet). Local vet visit isn't much, and most of them don't even charge you for fluids.
Good luck to anyone in a similar situation. Just make sure you give them lots of love and keep your hopes up! A lot of cat's do well, and I know it's horrible seeing them paralyzed, but they do have a strong chance! I'm not an expert or anything, I'm just passing on what I learnt from my experience, and what I was told by vets, in the hope that it gives anyone else extra info and your kitty a better chance of survival.