Let’s talk about anesthesia. To pet owners, it can sound like a scary thing to be avoided at all costs. To us veterinarians, though, it is a daily and necessary part of keeping your pet healthy. When we do it well and safely, we can fix common pet problems like broken teeth and really bad ear infections. Although anesthesia sounds like a scary word, just think about doing any sort of medically necessary procedure without it (remember doctors used to be called “sawbones”?). With modern protocols and medications, people and animals don’t experience pain during these procedures, but we’ve all heard about somebody’s loved one having a problem or even died when they “went under”, and so the fear remains. So, the question we’re going to answer today is, how high of a risk is it? And, how worried should you be if we recommend an anesthetic procedure for your pet?
A study from the UK reviewed every procedure using anesthesia or sedation in a large group of veterinary hospitals. They collected data from almost 100,000 procedures in dogs and almost 80,000 procedures in cats. That is quite a lot of data for a veterinary study. Then the question they asked was, “how many of these animals died and are there any risk factors?” Here’s what they found:
For all dogs, the risk of death was about 0.17%, or about one in six hundred cases. For cats, the risk was 0.24%, or about one in four hundred cases. That’s not a high risk, but those numbers are a bit misleading, and here’s why: those numbers are coming from ALL the cases the group looked at over two years. Not only were young, animals included in those numbers, but also the high risk and emergency cases such as pets that had been hit by a car or may have had cancer. The group was interested to see what the risks were for healthy and sick pets, so they looked at the numbers more closely. The numbers had to be lower for a healthy young dog getting spayed than for an old dog with a ruptured spleen tumor, right?
Yes, of course. And that is exactly what the data showed. The researchers used a scoring system to rank patients based on their overall risk for anesthesia. Here are the different classes:
Class 1: Minimal risk of normal healthy patient with no underlying disease. Think of a one year old dog getting neutered.
Class 2: Slight risk of a slight to mild systemic disease. Think of a cat with mild dental disease getting a cleaning.
Class 3: Moderate risk, obvious systemic disease. Think of a dog with a low grade heart murmur who needs a skin mass removed.
Class 4: High risk with severe, systemic, life-threatening disease. Think of an older cat with a blockage in its intestines that has been throwing up for three days.
Class 5: Extreme risk, moribund; patient will probably die with or without surgery. Think of a dog that has been hit by a car and is bleeding badly.
For simplicity’s sake, let’s call animals in Class 1 and 2 “healthy”, and animals in Class 3, 4, and 5 “sick”. When using this system, healthy dogs had their risk drop to 0.05% or one in two thousand. For healthy cats, the risk went to 0.11% or one in nine hundred. Let’s compare that with sick patients; in dogs and cats the risk of death with anesthesia is about 1.4%, which is one out of every seventy cases! Just think about that for a second. A sick dog’s anesthetic risk of death is TWENTY-SIX times higher than a healthy dogs. For cats, it’s about THIRTEEN times higher.
Well, “who cares” you might say, “my pet isn’t sick, so the risk is low”. That might be true right now, but early intervention is the BEST way to keep your pet in the low risk categories. Just think, a dog with mild dental disease that goes untreated could easily go from a Class 2 risk to a Class 3 within a year, increasing their risk of death SIX TIMES. Running that pre-anesthesia blood panel is going to help us determine which category your pet is in. This is one of the many reasons we focus on preventative medicine here at Coastal Animal Hospital.
Some of the other risk factors for anesthetic death highlight how important preventative care is. Scheduled procedures were lower risk than emergency procedures. This makes a ton of sense, and not all emergencies can be avoided, but identifying problems earlier can steer us clear of some emergency situations. Also, dogs over 12 years old had a higher risk. This doesn’t mean we can’t do anesthesia in dogs over 12, but if your pet is getting up there in age, think about scheduling some of these procedures sooner rather than later. Some of the risk factors we may not be able to change, such as herding breeds having a four times higher risk, or dogs 10 pounds and under having a seven times higher risk.
There are a lot of things that we can do to lower this risk though. On your end, preventative care to reduce risk category is one of the most important. On our end, the way we perform anesthesia obviously plays a big role. For example, if you induce anesthesia by holding a mask with an inhaled gas over a pet’s face, it is associated with a SIX fold higher risk of death than using a more balanced technique. Here at Coastal, we NEVER “mask down” our patients, and they always receive a safer combination using a premedication and the inhaled gas is for maintenance only.
Another one of the significant findings from this study was that about half of all the deaths associated with anesthesia happened after the procedure was over, and most of those happened within 3 hours of finishing the procedure. At Coastal, we always ensure that our patients have a dedicated technician monitoring them, which typically only happens at large specialty or university veterinary hospitals.
So, what are the takeaways? First, we now have really good data to show that overall, the risk of death with anesthesia in dogs and cats is low, but especially low in healthy animals. Second, the risk to YOUR pet depends a lot on both keeping them healthy in the first place, AND how the anesthesia is performed. Anesthesia is not standardized amongst all veterinary hospitals, you might not get a dedicated technician, balanced protocols, or good monitoring equipment depending on where you go. At Coastal, we take great pride in offering you up to date and excellent care, which minimizes the risks for your beloved pets. For more information on how we minimize risks at Coastal – see our page on Safe Anesthesia.
References:
- Brodbelt DC, Blissitt KJ, Hammond RA, Neath PJ, Young LE, Pfeiffer DU, Wood JL. 2008. The risk of death: the confidential enquiry into perioperative small animal fatalities. Vet Anaesth Analg. Sep;35(5):365-73
- Matthews NS, Mohn TJ, Yang M, Spofford N, Marsh A, Faunt K, Lund EM, Lefebvre SL. 2017. Factors associated with anesthetic-related death in dogs and cats in primary care veterinary hospitals. JAVMA Mar 15;250(6):655-665
My dog is 15 and require dental treatment one vet said not worth it given his age that was last year
Yet today I was told his age is not a problem and it would cost £399 not sure what to do
It is hard when you get opposite advice from two different people! I don’t consider age to be a disease. I find most senior and geriatric pets need the most dental care because things tend to fall apart in their mouths in their later years. Yes, anesthesia has a higher risk of unexpected complications as they age. However, there is also a risk of leaving untreated dental disease and I tend to default more toward quality of life versus length of life. While I cannot comment on your specific pet since I do not know all of the details and have not performed an exam, evaluated bloodwork, etc – I can tell you there are very few pets that anesthesia is a contraindication because the risk of death is simply too high. With appropriate drug selection, monitoring, and skill, anesthesia can be safely performed in the vast majority of animals.
Best of luck.
-Dr. Evans
My dog needs dental work. Her teeth are bad and have been for a number of years. She’s 10 years old and only 4 lbs. She just had her check up and blood work done. Everything looks great. Doctor said she’s in great health and her heart is good. If I was to get the dental cleaning done he suggest do it sooner than later. He went through the pros and cons and walked me through step by step what he will do. I feel very confident with the vet. My only concern is my dogs size and weight. Looking for a second opinion. What are your thoughts?
Hi Maria,
While I can’t give specific advice for your pet, I can tell you that we routinely safely anesthetize small dogs to address their mouth and they come out the other size happier and healthier because of it. The biggest question is how the anesthesia is being performed and monitored. If done correctly, then the overall risk is low and dental issues will be a bigger risk to health.
Take care,
Dr. Evans
Hello. My 13 year old cat needs a dental, his teeth have been in bad shape for a number of years. The problem is that this year he developed stage 1-2 kidney disease and low grade lymphoma, for which he will recieve chlorambucil soon. I think anesthesia is way too risky in thus situatiation, he is eating although slowly, and he acts normal but i know his teeth are in terrible shape. I do not want to lose him and I want him to have a good quality of life and I fight for that every day to the point where he has a happy life, plays and purrs, so I would never forgive myself if after all this it’s a dental that kills him. I do not know how big the risks would be in his case. except for createnine being 1.71 his bloodwork is normal, but he is on 2.5mg prednisolone because of his ongoing gastritis that turned out to be low grade lymphoma and not IBD
I am sorry to her about all of the problems with your cat, poor thing! While I cannot give you advice on your cat without reviewing all of the medical history and performing an exam, I tend to look at this from the perspective of quality of life. If the mouth hurts, that to me is a bigger risk than anesthesia because if he stops eating or the bacteria from his mouth does more damage to his internal organs, that also can be terminal. I would recommend scheduling an exam and we can discuss our anesthesia protocols and how we can keep your cat as safe as possible and improve their quality of life.
I have 12 year old Yorkshire Terrier who has really bad teeth and everyone i know talks about it and I went to the Vet awhile back and they said she was fine but her teeth are rotting and loose and they suggest getting a extraction and dental cleaning but im afraid of her not waking up from the procedure im not sure what to do.
Poor pup! Bad teeth are such a common issue for these guys and it only gets worse the older they get. While I can’t advise you on your specific pet, I can tell you we encounter this exact scenario all of the time and routinely perform dentals and extractions successfully on older yorkies all of the time. The most important part is HOW the hospital is managing the anesthesia and it can be hard to tell from the outside. I would recommend scheduling a consult with us and we can discuss risks and benefits.
My dog has mammary cancer tumors, a hernia, and teeth problems. She is walking in circles and crying here and there and seems disoriented. She is a shin tux about 13 years old, unspayed and maybe 6 pounds or less. If she goes under surgery, do you think she will survive ? Is it worth getting the surgery to try to make her end of life more comfortable or should we just try to get her pain meds? I’m not sure what to do
She sounds like a sweet old lady with some real concerns! It is always a balance between risk of doing something and the risk of doing nothing, which can often be worse for them if they are living in pain. I would need to examine her and review her medical records to be able to give you any advice, but would be happy to do so. Please call the front desk to schedule an appointment and we can see if this is something that can be safely done.
My dog is 11 and a Chihuahua he needs dental like everyone else. Unfortunately i dont really have a choice in vet to do his dental. The problem is he has tracheal collapse which hes medicated for but not too often he gets hydrocodone when it flares up but its not took often maybe every few months. Im really worried they might not be fully prepared to do his dental. They have all the monitoring equipment but no special person to monitor it while hes under just the person doing the extractions is in charge. His blood work is great and other than that hes healthy. I was wondering how often dogs with tracheal collapse die under anesthesia/ after anesthesia because of the condition. I love him and id never want to lose him over something like that
I personally don’t get as concerned about tracheal collapse unless it is severe. Though I would be concerned if there is not someone dedicated to monitoring the anesthesia. I would continue to look around until you find a hospital that has someone in charge exclusively for monitoring anesthesia.
Hi Brian!
I have chihuahuas, and as you probably know, dental disease is awful with them. Throughout their lives they’ve had dentals, dental sticks, daily toothbrushing, and even that “Plaque Off” stuff. They still seem to get awful tartar, really quickly.
How far apart do you recommend dentals for chihuahuas, so that dental problems can be kept as minimal as possible? My current dogs are super seniors and lose a pile of teeth every time they get a dental, I’m hoping I can space them in some way that they stay clean and don’t need to be toothless at 12.
That is a good question. There is not a right answer and when I try to find the right balance of performing a cleaning under anesthesia and not wanting to put them under too often. My metric tends to be if I am continuing to pull teeth each time, then we need to do the cleanings more frequently. Based on that, we do have a couple of patients that get their teeth cleaned every 6 months and that seems to have stopped the constant need to extract teeth.