Understanding general anaesthesia: Safety, science and peace of mind

At Cotswold Vets, your pet’s safety is the heartbeat of our practice. While the thought of “going under” can be nerve-wracking for any pet owner, general anaesthesia is a routine part of modern veterinary medicine that allows us to perform complex procedures like laparoscopic spays with exceptional precision.

Quantifying the risk: What the science says

We want to reassure you that the risk associated with anaesthesia in healthy pets is remarkably low. While every medical procedure carries some level of uncertainty, we often look to large-scale studies to help quantify this for our clients:

  • The Numbers: Broadly speaking, studies suggest that the risk of a major complication in healthy dogs is approximately 1 in 1800.
  • Context Matters: This means that for the vast majority of our patients, the process is incredibly safe and smooth.
  • Our Commitment: We use these statistics not to cause worry, but to highlight why our expert care and pre-procedural checks are so important in maintaining these high standards of safety.

Common (and less common) complications

Most “complications” are minor and easily managed by our knowledgeable veterinary professionals. These might include:

  • Drop in Blood Pressure: This is seen in approximately 1 in 3 dogs undergoing a general anaesthetic. Fortunately, it is usually treatable (and often a side effect of the drugs we use), but patients with pre-existing organ dysfunction can be compounded by this so knowing about any issues beforehand with blood testing can help to keep things as safe as possible.
  • Regurgitation: This is seen in 1 in 100 dogs that are healthy and not prone to regurgitation. This is the reason we advise a starvation period to help minimise this risk.
  • Worsening of heart disease: Patients with moderate or severe heart dysfunction are at risk of developing complications (such as congestive heart failure) partly due to their heart having had to work at maximum capacity whilst under and the challenges anaesthesia has on the cardiovascular system. If your pet has underlying heart concerns then we will likely offer you a heart scan on a separate day before the procedure so we know what we are up against.
  • Worsening of canine cognitive dysfunction: This is largely extrapolated from the human data, but these observed age-related changes in routine and behaviour can worsen after general anaesthesia.
  • Allergic reactions: It is possible for pets to be allergic to any of the drugs that we use and whilst fortunately it is very rare, this can be quite challenging to deal with.

Now, to address the “elephant in the room” – as veterinary professionals, it would be an oversight not to mention that death is a known, albeit very rare, complication of any anaesthesia. We like to think of it like a flight safety briefing; it’s essential information, even though we fully expect a perfectly smooth landing!

Why we sometimes use “off licence” medications

In the UK, the RCVS and the Veterinary Medicines Directorate have a system for licensing drugs. However, in some situations, the best medicine for your pet might be “off-licence” (also known as the “Cascade”).

What does this mean? It simply means the drug is being used in a way not specifically detailed on its original UK marketing authorisation – often because a version hasn’t been “officially” licensed for every single species or specific scenario, even if it is the global gold standard for care.

  • Local anaesthetics: Drugs like marcain (bupivicaine) or lidocaine are often used to provide superior pain relief during a lap spay, ensuring your pet wakes up as comfortable as possible.
  • Life saving interventions: In an emergency, we may use medications like atropine or adrenaline. These are vital tools in our “crash box” that allow us to react quickly to any changes in your pet’s heart rate or rhythm.

Rest assured, we only use off-licence drugs when we believe they are the safest and most effective option for your pet’s specific needs.

Laparoscopy specific considerations

Because a lap spay involves a “keyhole” approach, there are a few unique factors we monitor during anaesthesia:

  • Abdominal pressure: We gently inflate the abdomen with carbon dioxide to be able to see clearly with our camera and have room for our instruments. Our anaesthetists carefully monitor your pet’s breathing to ensure they are coping perfectly with this slight change in pressure.
  • Positioning: Pets are often tilted slightly during the procedure to allow gravity to move organs out of the surgical view. We use padded supports and constant monitoring to ensure their circulation remains optimal throughout.

FAQ: Your peace of mind

1. How do you monitor my pet while they are asleep?
Your pet is never alone. A dedicated nurse monitors their heart rate, oxygen levels, blood pressure, and CO2 levels every five minutes, just like in a human hospital.

2. Is my older dog at higher risk?
Age is not a disease, but it does mean we take extra precautions, such as our recommended pre-anaesthetic blood testing, to tailor the protocol to their specific organ function.

3. Will my pet be in pain when they wake up?
Our goal is “zero pain.” We use a combination of pre-emptive pain relief, local anaesthetics, and post-operative medication to ensure they feel as pain free as possible throughout their recovery.