The head of the Tennessee Department of Corrections resigns after the botched execution of Christa Pike

The head of the US State of Tennessee's Department of Corrections submitted his resignation following the failure of the execution of death row prisoner Christa Pike on Wednesday.

Gov. Bill Lee announced the change on Saturday, in a joint statement with Frank Strada, commissioner of the Tennessee Department of Corrections.

Strada stated that his resignation was in the "best interest" of the state, describing the ongoing investigation into the incident as "entirely appropriate and necessary."

Pike, who was sentenced to death in 1996 for the murder of Colleen Slimer, survived after being injected twice, and is now in critical condition in a Tennessee hospital, while her lawyers seek to reduce her sentence.

“Commissioner Strada has served with integrity, and I appreciate his willingness to put the interests of Tennesseans first during this difficult moment,” Governor Lee said.

Lee ordered an independent review of Pike's attempted execution and halted all executions in the state for the year.

Pike's lawyers described the resignation as "justified," but noted that it "does not provide any assistance to Christa at this time."

“What happened to her on Wednesday reflects an institutional failure that goes far beyond the responsibility of any single person,” Pike’s legal team said in a statement. “We hope that the governor’s call for a comprehensive, independent review will reveal the deep problems with Tennessee’s entire death penalty system.”

Pike is receiving treatment at a hospital in Nashville, Tennessee, where doctors are trying to rid her body of the drugs used during the execution attempt, according to legal documents.

Pike was injected with two lethal doses of the drug pentobarbital on Wednesday, but remained alive, and was then transferred to the hospital by ambulance. Her attorneys stated that while she was receiving both doses, “she could be heard crying, moaning, and breathing loudly throughout the procedure.”

As of Thursday evening, she was unconscious, had been intubated and was on a ventilator.

The state Department of Corrections defended its approach, saying that "the protocol does not allow for additional actions beyond what has already been implemented."

Authorities have not yet announced whether they will attempt to execute Pike again, nor have they provided an explanation for what went wrong. On Friday, her lawyers submitted an urgent request to preserve “all evidence” related to her failed execution attempt.

Pike's lawyers had previously warned that her medical history and physical structure, including thrombocytosis - a condition that causes blood clotting - and the small size of her veins, put her at risk of "undue" pain and suffering during a lethal injection execution.

The execution attempt went ahead after several recent unsuccessful legal appeals filed by Pike's lawyers.

The US Supreme Court rejected two separate attempts to stop executions by lethal injection.

The governor of Tennessee also rejected a request for clemency submitted by Pike, the only woman on death row in the state.