The attempt to execute Christa Pike was supposed to end inside Tennessee’s death chamber.

Instead, it ended with an ambulance rushing her from Riverbend Maximum Security Institution to a Nashville-area hospital, where attorneys said she remained unconscious, critically ill and dependent on a ventilator days later.

Now, an anesthesiologist who examined the medical circumstances surrounding Pike’s case says he believes he knows what may have gone catastrophically wrong.

Dr. Joel Zivot, an Atlanta-based professor of anesthesiology and surgery retained as an expert by Pike’s defense team, believes the intravenous lines used to administer pentobarbital may have failed.

His theory is both straightforward and disturbing.

The lethal drug, he says, may not have reached Pike’s bloodstream in a sufficient concentration to kill her.

Instead, it may have leaked into the tissue surrounding her veins.

That could explain both her survival and the serious injuries her attorneys say appeared on her arms afterward.

According to a court filing from Pike’s attorneys, she arrived at the hospital with both arms swollen, burned and blistered.

Hospital personnel were working to remove pentobarbital from her system and stabilize her condition.

Zivot told PEOPLE that his medical opinion is that the veins containing the IV catheters may have ruptured or otherwise stopped functioning correctly.

If that happened, the drug being pushed through the IV would no longer travel efficiently through Pike’s circulation.

Instead, it could collect in surrounding tissue.

“The IV simply became non-functional,” Zivot said while explaining his theory.

He emphasized that if Tennessee’s intended quantity of pentobarbital had entered Pike’s bloodstream properly and reached the brain at a sufficient concentration, it would ordinarily be expected to cause death.

Pike’s survival, he argued, strongly suggests that enough of the drug never reached its intended destination.

The explanation remains an expert opinion rather than an official determination.

Tennessee authorities have not yet publicly established exactly why the execution failed.

Immediately after the September 30 attempt, the Tennessee Department of Correction said it had followed every step of the state’s established execution protocol.

The department also said the protocol did not authorize additional procedures after the steps already performed that evening.

That leaves a major unanswered question at the center of the investigation:

How could officials follow the written protocol and still produce an outcome in which a prisoner received two doses of an execution drug, remained alive and ultimately required emergency medical treatment?

What witnesses described inside the chamber only deepened that question.

The execution had already been delayed for hours by last-minute litigation before the process finally moved forward Wednesday evening.

When the witness-room curtain opened, Pike was strapped to a gurney with an IV line attached.

She delivered her final statement and initially appeared calm.

But several minutes later, witnesses said she began complaining about pain in her arm.

She asked whether what she was feeling was normal.

After the drugs were administered, Pike appeared at times to lose consciousness, but witnesses continued hearing loud breathing and snoring-like sounds.

She remained alive long after the point at which the execution was expected to be completed.

The Associated Press reported that the curtain separating witnesses from the execution chamber eventually closed for the final time at approximately 8:06 p.m.

Witnesses were later told to leave, and Pike was transported by ambulance to a medical facility.

Officials have not publicly detailed everything that occurred behind the closed curtain between the apparent failure of the lethal injection and the decision to begin emergency treatment.

Pike’s attorneys have focused heavily on the IV placement.

Attorney Randy Spivey said he counted at least seven apparent needle insertion points on Pike’s left arm and claimed that one needle appeared bent when it was removed.

Her legal team had warned before the execution that establishing reliable IV access could be unusually difficult.

Pike has thrombocytosis, a condition involving an elevated platelet count, and her lawyers had also cited her small and difficult-to-access veins when challenging Tennessee’s execution method.

Zivot believes that condition could be relevant.

Platelets help blood clot after an injury.

With thrombocytosis, he explained in another interview, clotting around an IV puncture could potentially interfere with the vein and obstruct the catheter.

If pressure then increased while the drug was being injected, the vein could fail, allowing pentobarbital to escape into nearby tissue rather than circulating normally through the body.

That possible leakage could also help explain the injuries described by Pike’s legal team.

Pentobarbital is strongly alkaline, and Zivot said exposure outside the vein can injure surrounding tissue.

According to Pike’s attorneys, her arms were swollen, blistered and burned when she arrived at the hospital.

Zivot described the apparent external injuries as potentially significant because they could provide visible evidence of where at least some of the drug traveled.

However, determining the complete medical consequences may take far longer.

Zivot warned that prolonged problems with circulation or oxygen delivery could potentially affect several organs, including the brain, heart, kidneys and liver.

Pike’s attorneys have specifically raised concern about possible brain injury.

Zivot cautioned that it was still too early to determine the extent of any lasting damage or even what her eventual level of recovery might be.

As of the most recent public statements from her attorneys, Pike remained unconscious and on a ventilator while physicians treated the consequences of the attempted execution.

Her case is now moving simultaneously through medical, legal and administrative channels.

Her attorneys have asked a court to require Tennessee officials to preserve evidence connected with the execution.

That evidence could become crucial in determining whether equipment failed, whether IV placement was inadequate, whether the execution protocol itself contributed to the outcome or whether other factors were responsible.

Meanwhile, Tennessee Gov. Bill Lee ordered a comprehensive third-party review and stopped the state’s remaining scheduled execution for 2026.

Lee said investigators need to determine why the result differed so dramatically from what state officials expected.

The governor has emphasized that the review must establish what happened before Tennessee moves forward.

The consequences have already reached the highest levels of Tennessee’s correctional system.

On October 3, Lee announced that Department of Correction Commissioner Frank Strada would resign.

The resignation came only days after Pike’s failed execution and amid growing scrutiny of Tennessee’s execution procedures.

Strada maintained that he believed the department had followed its protocol but said stepping aside was in the public interest as the investigation proceeded.

Pike’s execution attempt was particularly significant because Tennessee had intended it to be the state’s first execution of a woman in more than two centuries.

Pike, 50, was sentenced to death for the 1995 killing of 19-year-old Colleen Slemmer.

Prosecutors said Pike and others lured Slemmer to an isolated area in Knoxville, where she was beaten and killed.

Pike was 18 when the crime occurred and was convicted the following year.

Slemmer’s family had waited decades for the sentence to be carried out.

Her mother, May Martinez, witnessed the failed execution and later described watching Pike continue moving and breathing after the drugs had been administered.

Martinez said the failed procedure denied her family the closure they had expected after more than 30 years.

That dimension of the case has become impossible to separate from the growing questions surrounding the execution itself.

Pike’s attorneys argue that the state subjected their client to exactly the kind of prolonged medical ordeal they had warned could occur.

Slemmer’s relatives, meanwhile, endured an execution process that did not produce the outcome they had been told to expect.

Tennessee officials are now confronting questions from both directions.

And the medical mystery is not limited to why Pike survived.

Investigators must determine where the pentobarbital actually went, how much reached her bloodstream, whether either IV remained functional, and whether there were warning signs that should have caused officials to stop the procedure sooner.

Those answers could prove critical because Tennessee had already experienced another failed execution attempt earlier in 2026.

In May, officials halted the execution of Tony Carruthers after personnel could not establish the required secondary IV access despite multiple attempts.

Gov. Lee ultimately ordered the state to wait at least a year before attempting to execute Carruthers again.

Pike’s case was different.

The state actually administered the execution drug.

Twice.

And she survived.

According to the Death Penalty Information Center, the circumstances appear unprecedented in the modern era of American lethal injection: a condemned prisoner remaining alive after execution drugs were administered as part of a completed execution attempt.

For now, however, even the doctor offering one of the clearest medical explanations acknowledges that crucial information remains unknown.

Zivot’s theory provides a possible chain of events.

Difficult IV access may have contributed to vein damage.

A catheter may then have stopped functioning properly.

Pentobarbital may have leaked into surrounding tissue rather than reaching Pike’s bloodstream in a lethal concentration.

That leakage may have caused the serious arm injuries described by her lawyers.

But only medical records, physical evidence and the independent investigation can determine whether that sequence is ultimately confirmed.

Until then, Tennessee is left with two realities that would have seemed incompatible before September 30.

The state says its execution protocol was carried out.

Christa Pike is still alive.

And somewhere between those two facts lies the answer investigators are now under enormous pressure to find.