PHOENIX (AP) — Intravenous lines were placed correctly during the execution of an Arizona inmate whose death with lethal drugs took more than 90 minutes, a medical examiner said Monday.

Incorrect placement of lines can inject drugs into soft tissue instead of the blood stream, but the drugs used to kill Joseph Wood went into the veins of his arms, said Gregory Hess of the Pima County Medical Examiner's Office.

Hess also told The Associated Press that he found no unexplained injuries or anything else out of the ordinary when he examined the body of Wood, who gasped and snorted Wednesday more than 600 times before he was pronounced dead.

An Ohio inmate gasped in similar fashion for nearly 30 minutes in January. An Oklahoma inmate died of a heart attack in April, minutes after prison officials halted his execution because the drugs weren't being administered properly.

Hess said he will certify the outcome of Wood's execution as death by intoxication from the two execution drugs — the sedative midazolam and the painkiller hydromorphone — if there is nothing unusual about whatever drugs are detected in Wood's system.

Hess' preliminary findings were reported previously by the Arizona Capitol Times (http://bit.ly/1thLaFe ). Toxicology results are expected in 4 to 6 weeks from an outside lab.

Hess is chief deputy medical examiner for Pima County, which conducts autopsies for Pinal County, where the prison is located.

Wood was sentenced to death for the 1989 killings of his estranged girlfriend, Debbie Dietz, and her father, Gene Dietz.

Wood was the first Arizona prisoner to be killed with the drug combination. Anesthesiology experts have said they weren't surprised the drugs took so long to kill him.

Arizona and other death-penalty states have scrambled in recent years to find alternatives to drugs used previously for executions but are now in short supply due to opposition to capital punishment.

Arizona Gov. Jan Brewer has ordered the Corrections Department to conduct a review of the execution of Wood.