There you are, being wheeled off into surgery, expecting total unconsciousness. After all, that’s what anaesthesia's all about, right?
A thought creeps into your mind: but what if you wake up during the operation?
Urban legends and myths say this can happen, and to be technically factual – yes, it is possible.
Needle in a haystack
The American Society of Anesthesiologists (ASA) say that anaesthesia awareness, as it’s called, happens in one in 10 000 cases. In other words: few and far and between. In fact, if we take high-risk patients and surgeries into tally, this number drops to one in about 40 000.
Still, it’s a worrying thought. Experts point out that anaesthesia awareness is most likely to happen during a high-risk surgery, with heart surgery or a Caesarean section for example.
First, let’s understand how anaesthesia works. Anaesthesia is medication that numbs the pain of surgery by relaxing your muscles and putting you to sleep. Think of it as temporary hypnosis. When you need an operation, there’s often a choice of the type of anaesthetic you’ll need to enable the surgeon to perform the operation.
If the operation is on the surface of your body, a local anaesthetic may do the trick. If the operation is a larger one, and is on one of your limbs, a nerve block to the area of the operation may be all that’s necessary. Conscious sedation, a very light form of anaesthesia where you don’t lose consciousness, is also becoming increasingly popular. This type of anaesthesia can be used for different types of procedures, from dental procedures to plastic surgery.
In most cases, your anaesthetist will inject an intravenous induction agent into the drip and you’ll drift off to sleep within 30 seconds, You will wake up later with no memory of what was done.
Awake and asleep
There have been cases of people waking up during surgery or simply being aware of something happening. This awareness can manifest as a vague recollection, a feeling of pressure or slight pain. Others report feeling like they were in a dream that felt real, and having an idea of their surroundings.
The most common outcome, according to the ASA, is that of hearing noises and sounds. “If you look at the effects of anaesthetics on the brain, the auditory system is the last to shut down, so it makes sense,” they say. On the list of least likely things to happen is opening your eyes.
"The anaesthesia puts you to sleep, so your eyelids shut naturally. Even if you regain consciousness, the anaesthesia still restricts muscle movement so your eyes will stay shut,” explains Dr Daniel Cole of the ASA.
"But there's still 10–20% eye opening when you sleep. So, during surgery, we will cover the patient's eyes or tape them shut to prevent injury and keep the eyes clean."
Anaesthesia awareness happens in those rare cases where the anaesthetic fails to do its job. Call it bad medicine if you will. The disconcerting thing here is that an anaesthetic includes a pain-reliever and a paralytic – so in these uncommon cases of awaking during surgery, the patient is still technically “paralysed” and can’t indicate they’re awake.
Still, there’s no need to panic. Modern medicine is a wonder, and with a one in 10 000 to 40 000 chance of waking up during surgery. You’re safer on the operating table than in a car.
It’s always worth chatting to your doctor or surgeon before surgery and letting them know if you’ve had problems with anaesthesia before. And if you do experience this phenomenon, you can and should get counselling thereafter to soothe any feelings of confusion and trauma.
Good to know
- Your anaesthetist will be present throughout your surgery. So, be assured that he will take care of anything unusual that might happen.
- According to the Royal College of Anaesthetics in the UK, “Most reported episodes of awareness are short. Three-quarters of those who experience accidental awareness have an experience that lasts less than five minutes.”
While anaesthesia awareness is rare, a few risk factors emerged in studies. These include:
- Ages 25-40
- Being a woman
- Types of surgery (obstetrics, cardiac, thoracic)
- Anaesthetic given in an emergency
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