A lawyer for convicted murderer Christa Pike says that she woke up in hospital "angry and confused" after she survived a botched execution attempt last week.

Her first words were to ask "Where am I?" and "Who are you?", Randy Spivey told a news conference.

Pike, who was sentenced to death after murdering Colleen Slemmer with her then-boyfriend in 1995, survived two lethal injections on 30 September in Tennessee.

Experts and her legal team say her apparent recovery is unprecedented, and that no other US inmate has survived a lethal injection from executioners.

A court on Wednesday ordered the state of Tennessee to preserve all evidence related to the failed execution.

Pike, 50, continues to receive critical medical care and is being restrained at her hands and feet in her hospital bed, her lawyers said at the news conference after a court hearing on Wednesday.

Spivey said that her legal team believed for days that she was brain dead, and expected her to be taken off life support at any moment.

However, in a "shock to everyone", she began to talk on Tuesday, while recalling only limited details about the execution attempt.

Pike, he said, had helped the execution team find a vein in her arm, and she was kind and polite while she was being injected.

Then she woke up in a hospital with a tube down her throat and people she didn't know. Both of her arms, he said, are now "tremendously swollen". She also has a blood clot in one of her arms, pneumonia, and is not able to swallow, he said

"We don't know the toll all of this will take" on her mental health, Spivey said, noting how she was left "angry and confused" by the ordeal.

Pike is believed to be the only person to survive an execution attempt by lethal injection.

After it became clear Pike would not die, following two rounds of the drug pentobarbital, she was taken to hospital, where she remained unconscious for days as medical staff cleared her body of the injected chemical.

Earlier on Wednesday, lawyers appeared before a judge for an emergency hearing, where her team requested that all evidence from the botched execution be preserved.

That evidence could lay the groundwork for a future lawsuit against the state.

Luke Ihnen, one of Pike's lawyers, began by describing the "roadblocks" that have made it challenging to communicate with his client.

"Up until yesterday our client was unconscious, and unable to communicate," he told Judge Chancellor I'Ashea Myles. Pike is now "speaking limitedly", he said.

Tennessee Assistant Attorney General Will Ayers called attention to the "unusual procedural position here", prompting agreement from the judge. He argued that an emergency motion was unnecessary because the state is already compelled to preserve evidence.

Still, Judge Myles ordered that "anything that was in the actual room needs to be preserved and maintained," including IV lines and syringes, as well as waste, like packaging, inserts, and labels.

The judge also demanded documentation on Pike's psychological condition prior to, during and after the 30 September execution attempt.

She advised the state to take "special care" not to misplace or accidentally delete any information that may be pertinent to the case.

Asked by the judge whether the state intended to reschedule execution for Pike, Ayers said he did not know the answer.

Tennessee Governor Bill Lee has ordered a pause on all executions in the state for the rest of the year, and has said he wants answers about what went wrong. The state's prisons chief said he is resigning after the failed execution.

Ihnen asked the judge to allow Pike access to a phone so she can call her lawyers, and they can have "continuous liberal access to Ms Pike". He said they were kept waiting for over two hours during a recent attempt to visit her in hospital.

Ihnen added that Tennessee prison officials are keeping her "shackled" to her hospital bed, despite requests from medical staff that the handcuffs be removed.

Her lawyer also requested that the Tennessee Department of Corrections be required to notify his team 48 hours before she is transferred from the hospital to any state hospital or other government-run facility.

Reuters The lawyers seen in the courtroom Ayers (left) argued the case for the state, while Ihnen (far right) represented Pike

Pike was 18 when she and her then-boyfriend, Tadaryl Shipp, beat, tortured and killed 19-year-old Slemmer, whom they had met at a job training camp for troubled teens.

Shipp was 17 years old at the time, meaning that he was spared the death penalty for his part in the attack because he was not yet legally an adult at the time. He remains in prison. (BBC)

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