Why Fasting Your Pet for Surgery Is so Important?

Fasting Your Pet for Surgery

It’s pretty standard for doctors to ask you or your pet to skip eating before surgery, whether you’re a human or a furry friend. They do this to lower the chances of any problems during or after the operation, especially those related to the anaesthesia. But is this really necessary?
Before pet surgery fasting fasting is super important because it helps prevent them from throwing up or breathing in anything dangerous during the procedure. When their stomach is empty, there’s less stuff that can come back up or go down the wrong pipe. So, ideally, your pet shouldn’t eat or drink anything before surgery.
Eventually, most pet owners will find themselves facing the decision to have their pet undergo surgery, whether it’s a dog, cat, or even a little pocket pet. If you’re feeling unsure about the whole fasting thing, this guide can give you a hand.
Keep reading to find out how long your pet should fast before surgery, including when to stop giving them food or water.


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Why Do Pets Have to Fast Before Surgery?

Pets need to fast before surgery to avoid throwing up or breathing in anything dangerous while under anaesthesia, which can be deadly. Even nibbling on a little snack during the fasting time can be risky, so it’s really important to make sure your pet doesn’t eat or drink before their surgery.
During surgery, there’s a risk of vomiting, especially a condition called Gastroesophageal Reflux (GER) or regurgitation, which is pretty common in dogs and cats.

When dogs are sedated, it helps their organs relax, except for the brain, heart, and lungs which keep going. But this relaxation also affects the “gatekeeper” of the stomach. So, if that relaxes too much, your pet’s stomach stuff can flow back up to the throat, and your pet might throw up.
Pets getting moved around a lot before surgery, like from the waiting room to the x-ray room and then to the surgery room, increases the chances of them throwing up.
Aspiration is when stuff from the stomach gets breathed into the lungs. The thing that stops food from going into the lungs also relaxes during anaesthesia. If your pet aspirates, they could get pneumonia or even worse, complications that could lead to death.
Sometimes, if pets don’t fast before surgery, they can get a condition called esophageal strictures, where the tube that carries food gets narrowed because of stomach acid irritating it.
To make sure surgery goes smoothly, it’s really important for your pet to stick to the fasting instructions your vet gives you.

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How Long Should Pets Go Without Food Before Surgery?

Typically, vets will ask your pet to stop eating for about 12 hours before surgery. But the exact fasting time can vary based on factors like your pet’s breed, age, the type of surgery, and your vet’s advice.
The time it takes for your pet’s stomach to empty before surgery can differ. Sometimes, your vet might suggest a shorter fasting period, like around 8 hours since your pet’s last meal. However, sticking to a 12-hour fasting period is usually easiest, especially if it’s overnight at home. This longer time accounts for things like slower digestion or small mistakes.

That’s why a 12-hour fast is the most common recommendation. But for certain procedures, like specific surgeries for dogs, your vet might advise fasting for up to 24 hours. Keep in mind that younger puppies and kittens might only need to fast for 1 to 2 hours before surgery.
Different kinds of pets have different fasting rules. For example, ferrets might need to fast for 4 hours, while rats only need an hour. On the flip side, rabbits and guinea pigs don’t need to fast before surgery at all.
In emergency situations, it can be tough to fast a pet for a full 12 hours. Your vet will decide when it’s safe to do the surgery, as sometimes an animal’s stomach might be empty after just 4 hours. But when you’re fasting your pet at home, it’s safest to stick to the 12-hour fasting window – or whatever your vet suggests.

What to Feed Your Pet Before Surgery?

In the days and weeks before your pet’s surgery, stick to their regular diet. Avoid introducing any new foods or feeding them larger portions before they start fasting for the surgery. Just keep their meals routine and normal.
Leading up to your pet’s surgery, it’s important to maintain their usual diet as much as possible. This isn’t the time to try out new foods or switch things up for your pet.
Even though it might seem like a good idea to give them extra food or mix things up with new treats before surgery, it’s actually best to stick with their regular diet to ensure consistency before a major operation.


Is Fasting Harmful for Pets?

No, fasting isn’t harmful for pets. Most animals, including dogs and cats, can go without food for quite some time before surgery without any issues. In fact, it’s riskier to feed your pet before surgery than to have them fast. However, small animals like rabbits and guinea pigs shouldn’t be fasted.

There are actually some advantages to fasting. It helps pets eliminate toxins from their bodies and supports repair and regeneration. Fasting can even promote processes like cell renewal and cleansing, which helps the body combat viruses, bacteria, and unhealthy cells. It’s particularly beneficial for reducing inflammation in dogs.
Given these benefits, it’s perfectly safe for pets to fast before surgery. A 12-hour fasting period is generally not harmful.
However, fasting for too long can increase stomach acidity. Over-fasting beyond what your vet recommends can lead to burns in the oesophagus and cause a condition called esophageal stricture, where scar tissue narrows the oesophagus. That’s why it’s important to follow your vet’s advice on fasting duration, as it varies for each animal.
For animals like rabbits and guinea pigs, fasting is extremely dangerous and should be avoided altogether. Fasting can trigger gastrointestinal stasis, where the digestive system slows down, leading to serious health issues and even death due to bacterial overgrowth. But this applies specifically to these small herbivorous animals and doesn’t apply to cats or dogs.


Sum Up

Fasting before surgery is a crucial step to ensure the safety and well-being of your pet. It helps prevent complications such as vomiting, aspiration, and respiratory issues under anaesthesia. While fasting duration may vary depending on factors like the type of surgery and your pet’s individual needs, following your vet’s guidance is essential. Maintaining your pet’s regular diet leading up to the surgery and refraining from introducing new foods is also important to maintain consistency and reduce risks. Overall, fasting is not harmful for most pets and offers several benefits, including toxin elimination and support for bodily repair processes. However, it’s crucial to avoid fasting small herbivorous animals like rabbits and guinea pigs due to the risk of gastrointestinal stasis. By adhering to fasting instructions and working closely with your veterinarian, you can help ensure a smooth and successful surgical experience for your furry companion.


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