NASHVILLE (AP) — When multiple pharmaceutical companies objected to Tennessee using their drugs to kill death row inmates several years back, the scramble to find lethal injection chemicals needed to carry out state-sanctioned executions grew frantic.

"What are your thoughts on acquiring it through a veterinarian?" an unidentified official wrote in a 2017 text. "They sometimes have better access to it since it's widely used for euthanasia in animals."

"How would that even work?" asked a separate employee.

"They buy the stuff by the case," the first official later responded.

These text messages emerged among hundreds of documents released this week as part of a blistering independent report on Tennessee's lethal injection system. The communications span years, depicting a state determined to push forward with executions despite roadblocks to obtaining the drugs and questions about whether revamped procedures would keep inmates from feeling pain as they are put to death.

The result: The state put a single employee with no medical background in charge of procuring the drugs, and the state's own flawed lethal injection rules and communication lapses meant one of the required tests for the drugs wasn't conducted during any of seven executions since 2018 — two by lethal injection, five by electric chair. Under Tennessee's rules, the drugs need to be tested regardless of the method selected.

Additionally, the protocol offered no guidelines on basic precautions needed to keep the chemicals from going bad, like temperature or thawing requirements.

Earlier this year, Republican Gov. Bill Lee paused all executions after confirming the state failed to ensure its lethal injection drugs were properly tested before the scheduled execution of Oscar Smith. Lee halted Smith's execution an hour before he was supposed to die.

The governor later called for the third-party investigation and report, which was released Wednesday.

That independent review also found no evidence the state provided the pharmacy in charge of testing the drugs with a copy of its lethal injection protocol. Nor was there any evidence the state ever told the pharmacy it had to test for endotoxins on all injection chemicals until the night before Smith's planned execution, the report said.

Other revelations about the typically secretive execution process included:

— A text exchange showing the state spent more than $1,000 for an overnight shipment of a key sedative for the lethal injection of Donnie Johnson in 2019.

— A separate text exchange between the state's lethal drug procurer and the owner of the supply pharmacy showed them chatting about whiskey and beer as they conferred on key details about testing execution drugs.

— An unidentified state official, sending a text message hours before the Smith execution was paused, warned: "We are preserving everything so don't throw anything away or alter any stuff."

The report showed that the state ultimately opted not to buy pentobarbital from a veterinarian 2017, but did consider importing the barbiturate internationally before scuttling that over logistical concerns.

These discussions occurred while Tennessee was still relying on pentobarbital as the lone execution drug. When it became nearly impossible to obtain around 2017, the state pivoted to a three-drug process using midazolam — a short-acting sedative used in a clinical setting to help patients feel sleepy and relaxed before surgery.

Reliance on midazolam has faced growing criticism after its use with other chemicals in executions that went wrong in other states.

The report says state correction officials were warned in 2017 by a pharmacy's then-owner that midazolam "'does not elicit strong analgesic effects,' meaning 'the subjects may be able to feel pain from ... the second and third drugs.'"

The question about pain remains a key point of contention in the ongoing national debate about whether lethal injection violates constitutional protections against cruel and unusual punishment. But after the state's drug procurer promised to inform correction leaders of this warning, the department still chose to press ahead with a three-drug protocol using midazolam, vecuronium bromide and potassium chloride.

Following the review, Lee said he plans leadership changes in the department and will hire a permanent commissioner in January to replace the interim one. The new leaders, he said, will rework the lethal injection protocol in cooperation with the governor's and attorney general's offices. They'll also revise training specifics.

Meanwhile, Lee's temporary pause on executions expires next week, with no executions scheduled for 2023. The Tennessee Supreme Court, which sets execution dates, hasn't commented publicly on how it will proceed. But under an agreement in federal court between the state and attorneys representing two death row inmates, executions are expected to remain paused to give public defenders time to challenge any new execution protocol via the courts.

Lee delayed execution dates during the COVID-19 pandemic and offered reprieves during the recent investigation, but he hasn't taken anyone off death row permanently.

So far, the review has cost the state more than $219,000, according to records obtained by The Associated Press in a public records request.