Health & Medical

Is thirteen too old to be put under? It is one of the questions vets are asked most often, usually in an apologetic voice, and the answer has become a professional catchphrase: age is not a disease. It sounds like a line designed to move the conversation along. It is not. It is an accurate summary of how anaesthetic risk works, because what matters is not the years behind your pet but the state of the heart, kidneys, liver, lungs and circulation in front of the anaesthetist today. A robust fourteen-year-old terrier with good bloodwork is a safer patient than a poorly six-year-old with an untreated heart condition.

The honest version, though, includes the other half of the sentence. Age is not a disease, but age is where diseases accumulate, and that is why older patients get worked up more carefully rather than turned away.

What the pre-anaesthetic bloods are really looking for

Owners often assume the blood test is a pass-or-fail exam. It is closer to a map. A packed cell volume tells the team whether your pet is anaemic, which changes how well oxygen is carried while asleep. Kidney values and electrolytes matter because many anaesthetic drugs are cleared through the kidneys and because blood pressure support depends on knowing where you started. Liver enzymes and albumin speak to drug metabolism and to how much of a drug floats around unbound. Glucose, platelets and clotting all get a look, and in older cats thyroid function is frequently added, since an overactive thyroid changes the plan considerably.

None of this guarantees anything, and any vet who promises otherwise is overselling. It shifts the odds by catching the problems that can be caught and by letting the protocol be tailored rather than generic. Sometimes it changes the plan entirely: fluids started the night before, a different induction agent, a cardiology referral first, or a conversation about whether the procedure is worth doing at all. That last outcome is not the test failing. It is the test working.

You may also hear your pet given an ASA grade, a one to five scale used worldwide to describe physical status before anaesthesia. A healthy young animal for a routine procedure is grade one. A patient with mild controlled disease, such as a well-managed heart murmur, is grade two. The numbers climb through significant systemic illness up to a critically ill emergency. It is not a prediction for your individual animal, but it tells everyone in the room how much support to prepare.

The risk you are probably not weighing

Here is the part that gets lost. Declining an anaesthetic is not a neutral decision, because the thing you were going to fix does not pause while you think about it. A rotten tooth root in an elderly dog's jaw is a chronically infected, chronically painful structure, and leaving it there because the anaesthetic feels frightening trades a short, monitored risk for months of low-grade suffering. The same logic applies to a mass that needs removing while it is small, or a painful joint that needs imaging under sedation to be assessed properly. In older animals the untreated problem is very often the greater hazard.

The numbers themselves are reassuring. Large studies find anaesthetic-related death in healthy dogs and cats to be genuinely uncommon, a small fraction of one per cent, with risk rising as patients get sicker rather than simply older. The stories owners repeat to each other, about a dog who never woke up, usually date from an era of ether, minimal monitoring and no dedicated nurse. That is not what happens now.

What the day actually looks like

Fasting instructions have relaxed compared with a generation ago, and most practices now ask for a shorter fast with water left down until you leave home. Follow whatever your own vet says, because very small or diabetic patients have different rules.

On arrival there is a physical examination, a listen to the chest and a check that nothing has changed overnight. A premedication injection combining a sedative with a strong pain reliever goes in next. It takes the edge off the anxiety, and because it starts pain control before anything hurts, it cuts the amount of anaesthetic drug needed later. An intravenous catheter goes into a foreleg for instant access to drugs and fluids, and many older patients are given oxygen by mask for a few minutes beforehand to build a reserve.

Induction is an injection through that catheter, and consciousness goes within seconds. A breathing tube is passed into the windpipe and its cuff inflated, protecting the airway and delivering oxygen with a controlled amount of anaesthetic gas. From that point a nurse is dedicated to the patient and nothing else: heart rate and rhythm, oxygen saturation, exhaled carbon dioxide, blood pressure, temperature and depth of anaesthesia, all charted at short intervals. Warmed air blankets and heated mats hold body temperature, which matters far more in a thin old animal than owners imagine, because a cold patient wakes slowly and badly. Fluids run throughout, and local anaesthetic blocks are used wherever the procedure allows.

Recovery is supervised in a quiet, warm, dimly lit space with someone watching until the patient can hold up their own head and the tube comes out. Older animals take longer to look like themselves, and some disorientation or wobbliness that evening is normal. Grogginess persisting into the next day is not, and warrants a phone call.

Before you agree to anything, ask. Will bloodwork be done, and when will I hear about it? Who monitors my pet, and is that their only job during the procedure? Will there be an intravenous catheter and fluids? What is the pain plan afterwards? How will she be kept warm? Should I give her usual tablets that morning? A good practice answers all of it happily, because these are the questions of an owner who has thought about it, and thinking about it is exactly right.