All about lethal injection pentobarbital that failed to kill Christa Gail Pike, twice

In an uprecedented event, a death row convict in Tennessee survived two dosages of a lethal drug on Wednesday. Christa Gail Pike, who would have been the first woman executed in Tennessee in more than 200 years, was alive and loudly snoring after the attempted lethal injection and taken by ambulance from the prison.

Pike, 50, had been scheduled for execution at 10 a.m. Wednesday for the killing she committed at age 18.An appeals court stopped the lethal injection just an hour before it was to start and hours later the U.S. Supreme Court overturned that stay.

Officials gave Pike two doses of pentobarbital. The state's execution protocol calls for a secondary set of drug syringes to be administered "if the inmate is not deceased" after the first set. It does not spell out what happens if the subject is alive after the second set. Seven other people have survived medical problems due to the execution team's failure to access a vein to administer lethal injection drugs, but no one has stayed alive after receiving the drugs used in such executions, officials added.

What is pentobarbital?

Pentobarbital belongs to a class of drugs known as barbiturates. Developed in the late 19th century, barbiturates suppress activity in the central nervous system and have been used for conditions including sleep disorders and epilepsy.

At high doses, barbiturates can suppress breathing and cause death. Because of the risks associated with overdose and the development of newer medications, barbiturates have largely been withdrawn from routine medical use over the past several decades.

US states use different drugs and drug combinations for lethal injections. Midazolam and pentobarbital have been among the drugs used in these executions.

During Joe Biden's tenure, then-Attorney General Merrick Garland withdrew the federal government's pentobarbital lethal-injection policy. A Justice Department review of scientific and medical research had found “significant uncertainty” over whether the drug's use could result in unnecessary pain and suffering. The Trump administration later reauthorized single-drug lethal injections using pentobarbital. The same method had been used in 13 federal executions during Trump's first administration, more than under any other US president in the modern era.

Since capital punishment was reinstated in the US in the 1970s, more than 1,600 prisoners have been executed, with the vast majority of executions carried out by state authorities.