Doses and (oral) mucosas

July 29, 2017

Dr. Garret Pachtinger shares the many reasons felines and canines vary in medical responsesespecially when it comes to drug doses.

Cats: basically small dogs, right? Um... not even close. Photo: Shutterstock.comWe know, we know. You've heard a million times that cats are not small dogs. But maybe the differences are never so dire as when calculating a drug dosage. From shock and cardiac response to nutritional needs, CVC educator and VETgirl Co-Founder Garret Pachtinger, VMD, DACVECC, listed major and minor differences that could mean life or death within veterinary patients at a recent CVC.

One of the big differences between feline and canine patients, no matter the size, is the difference in drug doses and metabolism. Compared with their canine counterparts, feline patients metabolize and generally tolerate certain medications differently. Here are three specific tips from his session:

First thing's first: Dr. Pachtinger wants to be clear that a little goes a long way in terms of doses of medications used in cats.

00:00 Who would have ever thought cats could be called more sensitive than dogs? (Kidding, we know they're big softies, even when they're plotting world domination.) In the case of diuretics, it's true.

00:10 Dr. Pachtinger explains why cats being more sensitive to some drugs, and why that can be both a good and bad thing.

00:37 To give an example, Dr. Pachtinger takes a dog that presents at a clinic with congestive heart failure and compares it to a cat in the same situation. He gives his suggested initial dosages for both species, too.

When performing procedures, such as a thoracocentesis, size matters.  Specifically when choosing the size of the collection syringe and penetrating needle, Dr. Pachtinger says.

00:00 For most sized cats that are not obese, his go-to thoracocentesis set up includes a 10- to 20-ml syringe and a 19- or 21-ga needle. 

00:23 Dr. Pachtinger says he doesn't tend to go bigger than his go-to syringe size, and explains exactly why.

00:32 Now he gives his go-to syringe and needle combo.

Buprenorphine and oral mucosa: a fan favorite-at least, it's a favorite of Dr. Pachtinger, who's a fan of the partial opioid agonist.

00:00 Dr. Pachtinger highlights two studies examining buprenorphine dosages and metabolism in cats and dogs when it comes to giving oral transmucosal buprenorphine. The final conclusion: in cats possibly give higher doses. In dogs, because a markedly higher dose needs to be given oral transmucosally as compared to intravenously, you have better options for analgesia in dogs.

00:35 Here's the nitty gritty of the chemical differences that both species have, and why you can't treat each the same.

1:03 To give an example of why dogs have other choices beside taking doses of buprenorphine oral transmucosally, Dr. Pachtinger compares other dogs to a tea cup Chihuahua that, c'mon, you all know is hard to dose with anything