Here’s What Happens When You Wake Up During Surgery

It’s a clinical phenomenon called anesthetic awareness.

“Anesthetic awareness, also known as intraoperative recall, occurs when a patient becomes conscious during a procedure that is performed under general anesthesia, and they can recall this episode of waking up after the surgery is over,” Dr. Daniel Cole, president-elect of the American Society of Anesthesiologists, told BuzzFeed.

Patients might remember it happening straight after surgery or sometimes days or weeks later! 

One to two people out of 1,000 wake up during surgery each year in the United States.

“It’s not a huge number, but it’s enough people that it’s definitely a problem,” says Cole. Plus, the true rate could be even higher. “The data is all over the place because it’s mostly self-reported.”

“Ideally, the anesthesiologist would routinely see the patient post-operation and ask them about intraoperative awareness,” he says. But this opportunity is often lost because patients are discharged or choose to go home as soon as they can after surgery. “Even if they remember three, five days later, they might feel embarrassed and don’t want to make a big deal so they don’t mention it to their surgeon. So there can be underreporting of awareness."

It happens when general anesthesia fails.

General anesthesia is meant to keep the patient unconscious or "asleep" during surgery, and make sure they have no memory of the entire procedure. If there is a decreased amount of anesthesia, the patient can start to wake up.

The cocktail of medication in general anesthesia often includes an analgesic to relieve pain and a paralytic. The paralytic does exactly what it sounds like — it paralyzes the body so that it remains still. When the anesthesia does fail, the paralytics make it especially difficult for patients to indicate that they’re awake.

And it’s not the same as conscious sedation.

Conscious sedation, sometimes referred to as “twilight sleep” is when you’re given a combination of a sedative and a local or regional anesthetic (which just numbs one part or section of the body) for minor surgeries, and it’s not intended to knock you out completely or cause deep unconciousness. It's what you might get to get your wisdom teeth out or getting a colonoscopy. With conscious sedation, you may fall asleep or drift in and out of sleep, but this isn’t the same as true anesthetic awareness, says Cole.

Contrary to popular belief, it doesn’t usually happen right in the middle of surgery.

“The anesthesiologist is very aware that this can happen and never relaxes or lets down their guard at any point during the surgery, no matter how long,” says Cole. “Awareness tends to occur on the margins, when the procedure is starting and you don’t have the full anesthetic dose or when you’re waking up from anesthesia, because it’s safest to decrease the amount of anesthesia very slowly and gradually toward the end.”

This also depends on the surgery and the patient, though. 

Patients often report hearing sounds and voices.

“The most common sensation is auditory,” says Cole. Patients will report that they were aware of voices, and even conversations that went on in the operating room — which can be especially terrifying if loud tools are involved. “If you look at the effects of anesthetics on the brain, the auditory system is the last one to shut down, so it makes a lot of sense.”

And opening your eyes to see the surgeons operating on you? Basically impossible. “First of all, the anesthesia puts you to sleep, so your eyelids shut naturally. Even if you regain consciousness, the anesthesia still restricts muscle movement so your eyes will stay shut,” Cole explains. “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.”

Few patients experience pressure (and rarely pain) during anesthetic awareness.

Less than a third of patients who report anesthetic awareness also report experiencing pressure or pain, says Cole. “But that’s still one too many, because the patient is kind of locked in and aware of what’s happening to them but unable to move, which is terrifying.”

Typically, sufficient analgesic (pain reliever) is given, so that even if you wake up you won’t feel pain. “More often, we use an anesthetic technique which includes a morphine-type drug to reduce pain. But this is really required for when the patient wakes up and they no longer have anesthetic so they are conscious and aware of pain,” Cole says.

Even if the analgesic wears off, there should be sufficient anesthesia to keep the patient unconscious and pain-free. “It’s rare. You’d have to both have insufficient anesthesia and insufficient pain medicine at the same time to feel prolonged pain during awareness,” Cole says.

Anesthetic awareness can cause anxiety and PTSD.

“The potential psychological effects of awareness range greatly,” says Cole. “It can cause anxiety, flashbacks, fear, loneliness, panic attacks — PTSD is the worse. It’s been reported in a small minority of patients, but it can be very severe.” says Cole. If doctors hear about someone having intraoperative awareness, they will try to get the person into therapy as early as possible, before memories can be embedded in a harmful or stressful way to patients.

“If you were in the hospital for a week and on day two we heard that you woke up during surgery, we’d get a therapist in the same day. We always want to mitigate so we can try to reduce the severity of symptoms,” Cole says.

It’s most often caused by an equipment malfunction.

General anesthesia can either be given through an IV or more commonly as gas which is breathed in through a mask. If the equipment in either of these were to malfunction, and the anesthesiologist wasn’t aware of it because the signal that gas is too low doesn’t work, for example, then patients would stop receiving medication and start to wake up. Again, this is terrifying but rare.

“The anesthesia equipment is like an airplane,” Cole says. “The anesthesiologist will do a pre-flight check and go over all equipment to make sure it works. But sometimes, that equipment can malfunction as short as an hour later so it won’t show up before taking off.”

Likewise, there is equipment used to monitor the patient’s vitals and brain activity, which can also fail to signal to doctors that the patient is waking up.

Less commonly, it’s the physician or anesthesiologist’s fault.

“Any time humans are involved, human error is always a possibility — but it’s more common that technology fails,” says Cole. “Physicians and anesthesiologists are well-trained to look out for signs of awareness during surgery, which obviously includes any movement of muscles and changes in vitals.” Since paralytics are often involved, doctors also closely monitor other signs like heart rate, blood pressure, tears, or brain electrical activity for any red flags.

However, sometimes patients can be on medications that suppress the body’s responses and inhibit the monitoring systems from effectively picking up warning signs of light anesthesia and awareness. These incidences can make it difficult to detect awareness, so physician anesthesiologists must closely watch an array of signs.

It is more likely to happen during surgeries that require “light” anesthesia.

Anesthesia also comes with risk factors, and can be harmful depending on the surgery or patient’s risk. “Awareness can occur when there is too light of anesthesia, which we often do deliberately for high-risk situations,” says Cole. According to the American Society of Anesthesiologists, high-risk surgeries include heart surgery, brain surgery, and emergency surgeries in which the patient has lost a lot of blood or they can easily go into shock.

Or the patient may need a lower dose of anesthesia due to risk factors such as heart problems, obesity, a genetic factor, or being on narcotics or sedatives. “For instance, anesthesia depresses the heart, so a normal dose could be life-threatening to someone with heart problems,” Cole explains.

“Sometimes you have to make a trade off,” says Cole. “Would you rather have a high level of anesthesia which threatens your body’s life functions, or a low level which ensures safety but increases the risks of waking up during the procedure?”

…But if that’s the case, your doctor will talk to you about it first.

Patients often feel better knowing that the decreased amount of anesthesia is for their own safety. “We tell the patient that there’s an increased chance that you may hear some voices or fuzziness, but if it gets uncomfortable we can tell and will increase the dose,” says Cole. “Patients are more understanding and happy when they understand that the risk of waking up is for their own safety.”

Also, you should know that if you’ve had a previous incidence of awareness, that puts you at higher risk for another episode. Cole explains that in this case, doctors will spend a lot of time with the patient and anesthesiologist describing exactly what to expect, so that hopefully they won’t experience it again.

The chances of this happening are slim, and medical professionals are doing everything they can to ensure that this does not happen.

According to Cole, it’s always helpful to spend some time pre-operatively with the surgeon and physician anesthesiologist going over the procedure and how they’ll get you through it safely and comfortably.

“I do something called ‘patient engagement’ and ‘shared decision-making’ so I can make sure the patient understands literally everything. Some patients don’t want to talk about awareness because it will give them more anxiety, and they just trust us,” says Cole.