Christa Pike, the Tennessee death row inmate who survived two attempts to execute her by lethal injection, remains critically ill on a ventilator and her prognosis is unclear, her lawyer said on Sunday. Stephen Ferrell, an Assistant Federal Defender, told CNN that doctors are still trying to clear two doses of the barbiturate pentobarbital from her body, and that it may be several more days before it is known whether she will recover.

Pike, 50, was transferred to a hospital in Nashville, where she is being held under guard, after the attempts on Wednesday night. Ferrell said he was not aware that she had regained consciousness at any point. He has not seen her and is receiving information through the person she named as her medical power of attorney, whose identity has not been disclosed. Her lawyers have said her arms were burned and blistered by the drugs. "We don't know right now, and we may never know, what sort of torture she endured," Ferrell said.

Authorities have not explained what went wrong or said whether they will try again to execute her. The Tennessee Department of Correction has said the protocol does not allow for additional procedures beyond those carried out. Governor Bill Lee has suspended all executions for the rest of the year and ordered an independent review of the state's capital punishment system by former U.S. Attorney Ed Stanton. Corrections Commissioner Frank Strada announced on Saturday that he is resigning. In May, the state halted the execution of Tony Carruthers after staff could not establish a second intravenous line, making this the second failed execution in Tennessee this year.

Ferrell urged the governor to commute her sentence to life imprisonment "at the very least", noting that she has spent more than 30 years in prison, much of it in solitary confinement. He said that if she recovers, she may not do so fully and questions could arise about her competence. Her lawyers have also asked a court to order prison officials to preserve all records, communications, images and video from the execution. Pike's team had warned before the procedure that a blood-clotting condition and small veins raised the risk of unnecessary suffering.

Pike was 18 when she and her then-boyfriend, Tadaryl Shipp, killed 19-year-old Colleen Slemmer, a fellow student at the Knoxville Job Corps, in 1995. Prosecutors said Pike saw Slemmer as a romantic rival. The brutal killing drew intense media attention, and Pike became one of the youngest women sent to death row. Wednesday's execution was delayed by more than eight hours while the U.S. Supreme Court overturned an appeals court ruling that had paused it so that a claim about childhood sexual abuse could be reviewed.

Slemmer's mother, May Martinez, who supports the death sentence, said she broke down in tears when she learned it had failed and that the state owes her "a big apology". Ferrell argued that Tennessee, which keeps many details of executions secret, must be more open so residents can decide whether they support what is done in their name.