When is it too much? Interpreting fluid volumes

How much fluid is too much in a “healthy” dog or cat under anesthesia? In this video interview with dvm360 during the 2026 Fetch Charlotte Conference, Lydia Love, DVM, DACVAA, walked through a practical way to think about plasma volume, plus what it really means when your fluid rates start adding up.

Throughout the interview, she challenges listeners to rethink routine fluid administration and recognize when volumes are signaling an underlying problem rather than just good support.

Transcript

The following has been edited lightly for clarity.

Lydia Love, DVM, DACVAA: Hi. My name is Lydia Love and I'm a veterinary anesthesiologist. I currently work at NC State in Raleigh, North Carolina.

dvm360: You suggest considering total volume delivered as a percentage of blood volume. Is there a "red flag" percentage that should make a veterinary team pause?

Love: Yeah, I'd really like to think of it in regards to a plasma volume. So a plasma volume in both dogs and cat is around 45 to 50 mL/kg. And so if I have a healthy volume, replete hydrated animal who's undergoing a routine, not major elective surgery, if we get to about half of that, I'm going to start to think, wow, that's that's a fair amount of fluids.

And what's happening here? Is there something I didn't assess correctly about where this patient was starting, or are there ongoing losses that, you know, I haven't quite sorted yet? So in a healthy patient, if I'm getting toward 15-20, certainly 30 mL/kg. That's a lot of volume, and I'm really going to need to kind of take a step back and and see what's what's happening there.