Anaesthesia & Pain Management

Animals need to be perfectly still during certain procedures (radiography, ultrasound, CT, MRI) and unlike humans we cannot ask them to do this themselves! While in some cases we may try to use gentle physical restraint while comforting and distracting them, forcefully restraining an animal would result in unnecessary stress, possible injuries to both the animal and the operator, and we also want to avoid future fear of veterinary procedures. Sedation will therefore help your pet to relax and stay still and is overall a far safer option.

In contrast to sedation, anaesthesia will cause a transient loss of consciousness so that the animal will lie perfectly still, not feel stress or pain, and will have no recollection of the procedure. There are many reasons why we may choose to anaesthetise your pet rather than sedate them. For example, anaesthesia for certain investigations may be required when our staff are not allowed in the procedure room during brief procedures because of health and safety rules (i.e. exposure to ionising radiation in CT and X-rays; exposure to loud noises in MRI). In these cases we always have the ability to monitor them safely from behind a glass screen.

Furthermore, there are some cases, where although sedation may be perfectly adequate, we may advise anaesthesia because it would be safer for your pet. If your pet is undergoing a surgical procedure, anaesthesia is always required to ensure they feel no pain during the surgery.

The overall anaesthetic risk is very low in cats and dogs although it is still higher than in humans, and the actual risk to your own pet depends on multiple factors (e.g. age, concurrent illnesses), which we will discuss carefully on a case-by-case basis. Reported anaesthetic mortality in dogs and cats ranges from 0.17% to 0.69%, from 1 in 145 to 1 in 600, therefore the chances of surviving are greater than 99%. This is, however, the overall mortality and individual mortality can vary depending on how sick your pet is and the procedure performed.

Anaesthetists use a classification from 1 to 5 (called ASA classification which is the same used in humans) to indicate physical condition. An animal with a condition classified as ASA 1-2 (pretty much healthy) undergoing a low risk surgery, e.g neutering surgery, has a very low risk of death (0.009%, so 1 in 11111), but this risk increases with increasing ASA grade, age and for emergency procedures.

What is important for you to understand before coming to Granta Veterinary Specialists is that the chances of your pet dying due to anaesthesia or sedation, if your pet is relatively healthy, are likely to be very small. We will always be realistic in our discussions with you about the risks and complications and we will always weigh up every risk versus benefit.

Although we completely understand that the thought of your pet having a sedation or anaesthesia may concern you, we will always look at each individual case carefully and do what is in the best interest of your pet. Consequently, sedation and/or anaesthesia are advised only when the benefits outweigh the risks.

You can also be assured that a very skilled member of our anaesthesia team will look after your pet, and an anaesthesia specialist will supervise the procedure and be directly involved as necessary. If you have any concerns about the risks and effects of anaesthesia or sedation, please ask to speak with one of the anaesthetists.

The safest anaesthetic is the one delivered by a caring, compassionate, experienced, skilled professional, using modern equipment and following the most up-to-date scientific evidence.

Pre-anaesthetic blood work and its effect on anaesthetic risk is still the subject of debate. There is no evidence suggesting that routine blood work in every animal (or human!) before anaesthesia is effective in reducing the risk of complications and death. The chances of finding a significant blood abnormality that will affect anaesthetic management in an otherwise young and healthy animal are incredibly slim.

On the other hand, we know that once we consider specific breed, age or condition-related risks, some groups of animals will benefit from pre-anaesthetic blood testing and other investigations (for example cardiac ultrasound), as their result may affect the anaesthetic protocol (choice of drugs to be used) and perioperative care. We will assess the risk/cost/benefit of performing pre-anaesthetic tests and discuss them with you, as ultimately it will be your choice to decide what to do. We may ask you to complete a simple questionnaire to help us understand if pre-anaesthetic blood testing is advisable and if you wish to discuss this with an anaesthetist, please do not hesitate to ask.

Sedatives and anaesthetics affect the “valve” mechanism that normally prevents reverse movement of stomach content from the stomach to the oesophagus (food pipe). Anaesthesia and sedation will relax this “valve” which means the acid content of the stomach or food can leak (reflux) into the oesophagus and this increases the risk of inhalation into the trachea (windpipe), which can lead to a pneumonia.

Acid reflux can cause damage to the oesophagus, the trachea and the lungs. Although such damage is treatable, we obviously want to minimise this risk as much as possible. We know that having a stomach full of food will increase the risk of vomiting (which is another risk factor for inhalation of stomach contents), so it is usual to withhold food before surgery to make sure that food has transited out of the stomach before anaesthesia or sedation. This is why, if there is a chance that sedation or anaesthesia will be required, we will instruct you to offer only water in the 6 hours preceding your visit to Granta.

A prolonged starvation period should also be avoided, as this is known to increase the risk of acid reflux, so rest assured that if we are not planning to sedate or anaesthetise your pet soon after the consultation and admission to the clinic, we will ensure they are fed once we have settled them in.

In specific circumstances, we will instruct you to withhold food for a different period, or not to withhold food at all, based on specific considerations.

Locoregional anaesthesia consists of the numbing of nerves or spinal cord to completely stop sensitivity, including pain, from a specific area of the body and at Granta Veterinary Specialists we have a team of experts in this form of anaesthesia. This is the most powerful tool available to prevent anaesthetised animals from feeling any pain.

Examples of this are spinal and epidural injection (similar to those used in people for childbirth), and peripheral nerve blocks to selectively numb limbs or other parts of the body. Although powerful painkillers, like opioids (similar to morphine), can be administered to pets into their veins or muscles to control pain, this is not the same as blocking the nerve completely and will also result in some side effects (nausea, reduced food intake, vomiting, drowsiness).

Additionally, we know that the body reacts to ongoing pain by increasing its pain sensitivity, thus making control of pain more difficult. Locoregional anaesthesia prevents the development of increased sensitivity, abolishing the pain sensation during the most intense stimulation (surgery and immediate postoperative period), resulting in reduced postoperative analgesic (pain relief) requirements and hastened recovery and return to normal behaviour. The risk of complications is minimal, and the cost of performing the locoregional technique is offset by the fact that strong painkillers will not be needed to control pain.

Your pet will be able to walk and void urine before being ready for discharge. As some additional clipping of hair may be required, if this is a problem for you, please let us know and we can discuss the location and extent of the clipping and agree on which is the best option.

Recovery from sedation and anaesthesia is generally rapid, however it will also depend on the duration of the procedure and the drugs administered. If your pet is visiting us solely to undergo a diagnostic procedure under sedation, without risk of complications, he or she should be fully awake and able to be discharged within a couple of hours of the end of the procedure. The same would apply if your pet has received a full anaesthetic under similar circumstances.

In specific cases, overnight hospitalisation may be required to monitor for complications, for example after taking a tissue sample (biopsy), to ensure your pet is pain-free, and can void urine and eat. If your pet is undergoing surgery, hospitalisation for one or several nights may be required, depending on the condition and the progress your pet is making and we will try our best to give you an approximate stay length after your consultation, although understandably sometimes this might vary.

We believe the best place for your pets is with you at home, so be assured we will work with you to achieve the earliest discharge possible, without compromising safety.

We hope that by the time your pet is ready to be discharged, their aftercare should be quite straightforward. In most cases, good old-fashioned TLC is what is needed once they come home: plenty of rest, calm reassurance, and making them feel they are returning to an environment they are used to and love.

We will advise you on specific instructions at the time of discharge so we always book a discharge appointment with you so that we can discuss aftercare with you, at which point you can ask as many questions as you would like!

We never consider the discharge as the end of our relationship and would encourage continued communication, especially if recovery is not what you are expecting or have concerns.