It is a date Carol Weihrer will never forget. On 24 January 1998, the 52-year-old underwent what should have been a relatively routine operation.
Carol Weihrer still suffers after waking up during surgery
After suffering pain in her right eye for years, she decided to have it removed.
But the surgery turned into a living nightmare when she woke up in the middle of the five-hour operation.
Unable to move or indicate to the doctors that she was awake, Ms Weihrer had to endure surgeons pulling, gouging and cutting away at her.
"I was completely awake, I could even recount what the doctors were saying, the only thing I couldn't do was move.
"There was no pain but that didn't make it better. It was a different kind of trauma, worse than rape or war, because you cannot do anything to stop it.
"The worst thing was not being able to tell anyone. I couldn't yell or scream, I just lay there, helpless as the doctors carried on.
"I could feel the pulling and felt terrible pressure, at one point I even felt a burning sensation."
Ms Weihrer, from Virginia in the US, received an out of court settlement following the operation but the experience has had lasting consequences.
"I have slept in a reclining chair for the last six years as I can't face lying down and have had full blown post traumatic stress disorder."
But she is not the only person to have been experienced what is called anaesthetic awareness or intra-operative awareness.
Researchers estimate as many as one in 500 patients can recall surgery after undergoing general anaesthetic.
One in 500 patients wake up during surgery
It happens when the anaesthetic given to patients wears off because of either a problem with the equipment or the patient has a high resistance to the anaesthetic.
The patient remains paralysed by the muscle relaxants given but are aware of what is going on around them - some even feel pain.
Senior consultant anaesthetist Dr Ian Russell, from the Hull and East Yorkshire Hospitals NHS Trust, warned doctors were not taking enough precautions to stop patients waking up.
He said: "The normal signs doctors use such as blood pressure and heart rate are not very reliable."
Instead, he suggested a simple precaution called the isolated forearm technique whereby a tourniquet is attached to the patient below the elbow before administering the muscle relaxant so if the patient does wake up they can signal to the doctors.
But Dr Russell, who will be speaking about the issue at the 6th International Symposium on Memory and Awareness in Anaesthesia and Intensive Care which starts in Hull on Wednesday, said: "Unfortunately the method has had a bad press over the years so anaesthetists have tended to shy away from it, thinking it does not work, but it does."
He also said brain monitors, which are coming on to the market, could be used.
Ms Weihrer, who has set up the Anesthesia Awareness Campaign and will be addressing the conference on Friday, said she believed patients were going to have to take the initiative.
"Both precautions work but doctors just don't use them enough. I want to see patients asking for them.
"I have met a few thousand people who have suffered the same thing as me, I don't want to meet anymore."