Is it possible to wake up during surgery

Things improved more than years ago, when a dentist in Massachusetts publicly demonstrated that the anesthetic drug ether could block pain during surgery.

Within just a few months, anesthesia was being used in Australia, Europe and then around the world. Life-saving procedures like open-heart surgery, brain surgery or organ transplantation would be impossible without general anesthesia. General anesthesia affects your entire body. Other types of anesthesia affect specific regions. Local anesthesia—such as a shot of novocaine from the dentist—numbs only a small part of your body for a short period of time. Regional anesthesia numbs a larger area—such as everything below the waist—for a few hours.

Most people are awake during operations with local or regional anesthesia. General anesthesia has 3 main stages: going under induction , staying under maintenance and recovery emergence.

NIH-funded scientists are working to improve the safety and effectiveness of all 3. The drugs that help you go under are either breathed in as a gas or delivered directly into your bloodstream. Most of these drugs act quickly and disappear rapidly from your system, so they need to be given throughout the surgery.

A specially trained anesthesiologist or nurse anesthetist gives you the proper doses and continuously monitors your vital signs—such as heart rate, body temperature, blood pressure and breathing. Next, patients lose the ability to respond. General anesthesia looks more like a coma—a reversible coma. In rare cases, though, something can go wrong. About once in every 1, to 2, surgeries, patients may gain some awareness when they should be unconscious. They may hear the doctors talking and remember it afterward.

Worse yet, they may feel pain but be unable to move or tell the doctors. Alex Evers, an anesthesiologist at Washington University in St. Awareness occurs when the patient does not get enough anaesthetic drugs. Some awareness episodes are a result of problems with the equipment or delivery of the drugs, or mistakes made by the anaesthetist. Other episodes are due to the fact that the patient is too sick to get much anaesthesia. General anaesthetic agents cause low blood pressure and a slow heart rate — this is a problem if the patient is also bleeding or has heart failure.

Finally, some patients seem to be resistant to general anaesthesia. Women wake up quicker from anaesthesia than men and this may be why they report more episodes of awareness. As medical specialists in anaesthesia, our training includes checking the equipment and drugs, making a good plan for the patient, communicating that plan to the patient, keeping a keen eye on the patient and the surgeon!

We also have a good culture of reporting cases of awareness and discussing them at our regular quality assurance meetings. New monitors of brain electrical activity brain waves can help as well.

Our research project, the B-Aware Trial , showed that a bispectral index or BIS monitor was able to prevent most cases of awareness in patients having high risk surgery. The BIS monitor and other similar products are now widely used in Australia during general anaesthesia and the Australian and New Zealand College of Anaesthetists recommends these monitors be available for all patients at high risk of awareness.

Genetic studies have identified patients who are resistant, or very sensitive, to various drugs, because of their genetic makeup. For example, nearly half of general anaesthetics administered in the UK included neuromuscular blockers. These drugs temporarily paralyse the body, preventing spasms and reflexes that could interfere with the surgery, without raising the dose of the anaesthetic drugs to dangerously high levels.

Neuromuscular blockers can also ease the insertion of a tube through the windpipe, which can be used to ensure the airway remains open as well as to deliver oxygen and drugs, and to prevent stomach acid from entering the lungs.

This all makes anaesthesia as much art as science, and in the vast majority of cases, it works astonishingly well. But as with any medical procedure, there can be complicating factors. In some situations, you might be able to raise or lower your limb, or even speak, to show the anaesthetic is not working before the surgeon picks up their scalpel. The unfortunate result is that a small proportion of people may lie awake for part or all of their surgery without any ability to signal their distress.

Donna tells me about her own experience, during a lengthy telephone conversation from her home in Canada. She says that she had felt anxious in the run-up to the operation, but she had had general anaesthetic before without any serious problems. She was wheeled into the operating theatre, placed on the operating table, and received the first dose of anaesthesia.

When she woke up, she could hear the nurses buzzing around the table, and she felt someone scrubbing at her abdomen — but she assumed that the operation was over and they were just clearing up. The next thing she knew, she felt the blade of his knife against her belly as he made his first incision, leading to excruciating pain. She tried to sit up and to speak — but thanks to a neuromuscular blocker, her body was paralysed.

There was just nothing I could do. The frustration was immense. Eventually, she tried to focus all her attention on moving one foot, which she managed to wiggle very slightly — and felt astonishing relief when one of the nurses placed his hand over it. Before she could move it again, however, the nurse had let go. She tried a total of three times, all with the same result. But as the neuromuscular blockers began to wear off, she started to move her tongue around the tube stuck down her throat; it was a way, she thought, of signalling to the staff that she was awake.

Unfortunately, the staff misread her attempts at communication, and began to withdraw the tube prematurely, before the paralytic agent had faded enough for her lungs to be able to operate on their own. She assumed she would die. At this point, the operating room began to feel more distant, as she felt her mind escape in an out-of-body experience. A committed Christian, she says she felt the presence of God with her. It was only after the staff restored her oxygen supply that she drifted back into the operating room, to wake, crying.

That pain, the fear, the sense of absolute helplessness all still linger to this day — feelings of trauma that have led her to be put on medical leave from her job.

And that has meant a loss of independence and confidence, and the abandonment of many of the hopes and dreams that she had built with her husband. Founded in , it has now collected more than reports — most from North America — and although these reports are confidential, some details have been published , and they make illuminating reading. They seemed to be panicking. As you might expect, a large majority of the accounts — more than 70 per cent — also contain reports of pain.

It is the paralysing effects of the muscle blockers that many find most distressing, however. To make matters worse, all of this panic can be compounded by a lack of understanding of why they are awake but unable to move.

The result, he says, is that many patients come to fear that they are dying. Estimates of how often anaesthesia awareness happens have varied depending on the methods used, but those relying on patient reports had tended to suggest it was very rare indeed. The results, published in , found that the overall prevalence was just 1 in 19, patients undergoing anaesthesia. The figure was higher — around 1 in 8, — if the anaesthesia included paralysing drugs, which is to be expected, since they prevent the patient from alerting the anaesthetist that there is a problem before it is too late.

These low numbers were comforting news.