The nearly two-hour execution of convicted murderer Joseph Rudolph Wood has raised questions about the efficacy of lethal injection as a way to kill.

Despite the prolonged execution on Wednesday, prison and Arizona attorney general’s officials said the condemned inmate didn’t feel pain.

However, a well-known professor of anesthesiology and the Pima County medical examiner said there is no way to tell if he did or didn’t.

The execution procedure was the longest since the state resumed executing people more than two decades ago — more than triple the previous longest, that of Daniel Cook, whose 2012 execution took 37 minutes.

“Throughout this execution, I conferred and collaborated with our IV team members and was assured unequivocally that the inmate was comatose and never in pain or distress,” Arizona Department of Corrections Director Charles Ryan said in news release immediately after the execution.

Assistant Arizona Attorney General Jeffrey Zick also asserted the inmate did not feel pain, during Supreme Court arguments over an emergency stay of execution Wood’s attorney’s requested while the execution was ongoing.

“The brain stem is working, but there’s no brain activity,” Zick said, relating the information he was given from the execution room at that moment, according to a hearing transcript. He described Wood’s repeated open-mouthed gasps as “snoring” and an “involuntary reaction” similar to what happens when patients are taken off life support.

He also said Wood received a second dose of drugs partway into the execution.

But Joel Zivot, an anesthesiologist and professor of anesthesiology and surgery at the Emory University School of Medicine, said there’s no way to know for certain if a person feels pain during a lethal injection execution.

“They’ve not produced a shred of evidence to support that claim,” Zivot said.

Despite the widely accepted belief that unconscious people don’t, or even can’t, feel pain, Zivot said that’s not the case.

“The court and the public have grievously erred by wrongly claiming that unconscious individuals are incapable of experiencing pain,” he said.

Determining if an unconscious person experienced pain requires, in part, the ability of the person to convey their experience after regaining consciousness, he said.

In anesthesiology, doctors administer chemical compounds designed to save lives, Zivot said. In fact, many of the drugs have been engineered specifically to minimize the risk of death.

“What happened in Arizona is just another example that these compounds are not made for killing,” he said.

The Department of Corrections used a mix of midazolam and hydromorphone to execute Wood.

Midazolam is often used in surgeries because of its sedative and amnesic effects. Hydromorphone is a drug derived from morphine characterized by palliative and painkilling effects.

The same two drugs were used in Ohio in January to execute Dennis McGuire, a convicted murderer and rapist, whose execution also raised questions about the continued use of lethal injection because it took 25 minutes before he was pronounced dead.

A state of Ohio investigation, likewise, determined McGuire did not experience pain during the execution, saying the large dosages of drugs rendered him unconscious before “irregular bodily movements” similar to those Wood exhibited were seen.

But the report also cites a need to further examine the drugs’ effects.

Wood was found guilty in Pima County Superior Court of the shooting his former girlfriend and her father.

In 1989, after a stormy and often violent relationship, Wood set out to kill Debbie Deitz. In phone messages played at his trial, Wood intimated to Deitz that he would kill her and himself.

On Aug. 27, he drove to Deitz’s father’s midtown auto-body shop. Once there, Wood rushed inside, first shooting the father, Eugene Deitz, then turning his gun on Debbie Deitz.

Gregory Hess, chief medical examiner with the Pima County Office of the Medical Examiner, conducted an autopsy on Wood’s remains.

He said the question of how much pain a person endures prior to death is subjective and difficult to answer, particularly through an autopsy.

“That’s not really what an autopsy report is for,” Hess said.

He said Wood’s cause of death was still pending, as was a toxicology report that would examine the levels of chemical compounds in his system.

Hess also noted the placement of IVs in Wood’s veins was done properly, unlike past executions in which inmates’ veins were pierced through or missed completely.

In a news release Thursday, corrections chief Ryan upbraided media reports characterizing Wood’s nearly two-hour long execution as “botched.”

“This is pure conjecture because there is no medical or forensic evidence to date that supports that conclusion,” Ryan said in the release.

But the fact remains that Wood’s execution was by far the most drawn-out lethal-injection execution in the state’s history, and has drawn international attention.

Documents provided by the federal Public Defender’s Office in Phoenix show the previous longest interval from administration of the lethal dosage to time of death was 37 minutes, when Daniel Cook was put to death for a pair brutal torture killings in 1987.

Since 2010, the state has executed 14 people. Only Cook’s took more than 30 minutes. Eight were done in fewer than 15 minutes.

Wednesday’s execution has prompted discussions about the method of state-administered death similar to those following the 1992 execution of Donald Eugene Harding, who was put to death in the gas chamber for a pair of murders in Tucson in 1980.

Witnesses said Harding took small, gasping breaths for 11 minutes before he died. At the time, he was the first Arizonan to be executed since 1963.

Arizona voters approved a ballot initiative in November 1993 to switch from the gas chamber to lethal injection.

Zivot described lethal injections as “theater” created by state prisons to mimic a safe and clinical setting.

“It’s quite horrifying, but it’s not a medical act,” Zivot said. “To my mind it has never been proven to be safe.”

He noted that medical societies such as the American Medical Association do not condone members participating in executions.

He said states should institute immediate moratoriums on lethal injection.

Since Wood’s execution, Arizona Attorney General Tom Horne has said his office would stop seeking death warrants for the state’s death-row inmates pending an investigation. Gov. Jan Brewer ordered an inquiry into the execution.

Contact reporter Patrick McNamara at 573-4241 or On Twitter @pm929.