The gurney inside Nevada’s lethal injection chamber. The former state chief medical officer developed an experimental execution protocol that is being questioned by critics. (Nevada Department of Corrections)

The doctor who devised the nation’s first execution method using fentanyl did so in a matter of minutes.

“I honestly could have done it in one minute. It was a very simple, straightforward process,” said John DiMuro, who was Nevada’s chief medical officer when he developed the experimental protocol with the powerful opioid. The state planned to use it last month on death row inmate Scott Dozier, but a judge put the execution on hold just days before its scheduled date. DiMuro resigned from his post in October.

In an interview, DiMuro said he looked at the few drugs available to the prison system and quickly settled on a three-drug combination. He included fentanyl and based its use in the protocol on a procedure often used to anesthetize patients for open-heart surgery.

His protocol is under attack from lawyers representing Dozier as well as others. Fentanyl is part of a wave of new drugs and options being explored by some states because of their problems obtaining the products they long have used. Critics have decried the efforts as risky human experimentation.

Some have also questioned why DiMuro, a board-certified anesthesiologist, helped create the protocol. Many doctors view any involvement in executions as a violation of their Hippocratic oath to do no harm. Many medical boards ban members from participating or assisting.

But DiMuro invokes duty and more, noting that he was required by Nevada statute to collaborate with prison officials to help them come up with a viable lethal injection protocol once they could no longer obtain the drugs traditionally used.

“I was just following the law. I owed it to the citizens of Nevada to follow the statute, and I did everything that was required of me,” he said.

John DiMuro, Nevada’s former chief state medical officer, at his Reno medical office. (Scott Sonner/AP)

DiMuro said his choice of fentanyl should remain separate from the nation’s opioid crisis, which has thrust the drug into the headlines as thousands of Americans continue to die of overdoses.

“People are trying to make that leap that we did it because of the opioid crisis, but it had nothing to do with it,” he said. “Fentanyl is one of the most commonly used opioids. It’s in every operating room, and it’s safe and effective in the right hands.”

The protocol that DiMuro designed calls for inmates to first receive diazepam, a sedative better known as Valium. They would then receive fentanyl to cause them to lose consciousness. Large doses of both would cause a person to stop breathing, according to three other anesthesiologists interviewed.

Yet the new method also involves injecting inmates with a third drug, cisatracurium, to paralyze the muscles — a step some medical experts believe creates unnecessary risk of suffering. If the inmate wakes up after receiving the third drug, he could die fully conscious but unable to move or signal his distress, critics say.

The judge who postponed Dozier’s execution cited concerns about the cisatracurium. The case is awaiting review by Nevada’s Supreme Court.

DiMuro defends his inclusion of cisatracurium. The first two drugs don’t guarantee the person would stop breathing and could take longer to take effect, he said. “The third drug helps to hasten and ensure death. Instead of taking a long time, death would come in five to 15 minutes. Without the paralytic, it would be less humane.”

His decision to resign as Nevada’s medical officer was related to neither the execution nor any threat to his board certification, he said. He had served in the post about 15 months after many years in private practice and saw it as a way to perform public service. “I wanted to see if I could give something back and help,” he said.

He said he has no opinion on the death penalty and feels confident he did his best in designing the new execution protocol.

“The one thing I was able to do,” he said, “was to make sure this was done in the most humane way possible.”

Mark Berman contributed to this report.

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