The first two men Oklahoma executed after a six-year moratorium  had fluid in their lungs when they died, which can cause feelings of suffocation or drowning. The evidence could come into play in a federal trial over the state’s lethal injection protocol set for later this month.

Medical examiner’s reports for death row prisoners John Grant and Bigler Stouffer show both men had pulmonary edema, which can cause a heavy sensation in the lungs and difficulty breathing, particularly when lying down. 

Oklahoma has another execution set for Thursday. 

When Oklahoma executed Grant in October, media witnesses reported seeing Grant cough, vomit and convulse before dying. Bigler Stouffer was executed in December. He did not exhibit signs of distress during his execution, which took about 13 minutes. 

A normal set of lungs weighs about 900-1000 grams. Grant’s lungs weighed 1390 grams, according to an autopsy report. Stouffer’s lungs weighed 1510 grams, according to his autopsy report.

Donald Grant was executed by Oklahoma on Jan. 27, but his medical examiner’s report is not yet available.

The autopsy reports raise questions about midazolam, a sedative that is the first drug in Oklahoma’s three-drug protocol. Unlike the drugs Oklahoma used in past executions, midazolam is a sedative and not a painkiller. Critics say midazolam can cause the condemned to convulse, gasp, cough and wheeze during executions, possibly from excess fluid in the lungs.

Midazolam is typically used to sedate patients before surgery. Oklahoma began using midazolam in executions when it could no longer find a source to purchase pentobarbital. The state administers 500 milligram of midazolam at the beginning of executions — up to 100 times more than a regular dose.

The use of midazolam in Oklahoma executions will play a key role in the federal trial over the state’s execution protocol. The trial is set to begin on Feb. 28 in front of U.S. District Judge Stephen Friot. 

Attorneys for the 29 death row prisoners who are suing over Oklahoma’s execution method are expected to point to midazolam as a weakness in the state’s lethal injection protocol. 

An NPR study that looked at hundreds of midazolam executions across the country found pulmonary edema, a process by which the lungs rapidly fill with bloody, frothy liquid, in more than 80 percent of them.

When Grant was executed in October, media witnesses described him choking, vomiting and convulsing on the execution table after the drugs began to be administered. Grant was the first person Oklahoma had executed since 2014 after a series of high-profile failures led the state to halt executions and craft a new execution protocol.

Prison officials described Grant’s execution differently. Oklahoma Department of Corrections Director Scott Crow said Grant was unconscious when he began to regurgitate food he had eaten earlier in the day. The choking and convulsing, Crow said, was due to the vomit blocking his airways. 

Department of Corrections Chief of Operations Justin Farris testified in January that Grant, who was executed at 4 p.m., was found drinking soda and eating chips less than an hour before his execution. Following Grant’s death, the Department of Corrections shifted the time of future executions to 10 a.m.

Former state Sen. Ervin Yen, a long-time anesthesiologist, witnessed Grant’s execution and told The Frontier that vomiting and convulsing was “not uncommon” when using midazolam to sedate someone who had recently eaten. But Yen said he had no experience administering a large dose of the drug like the state uses in an execution. The state of Oklahoma is paying Yen to attend executions and testify in court as an expert witness, though the state will not release the details of his contract, saying it is a part of ongoing litigation and exempt from Oklahoma’s open records law.

Yen has testified in court he believes midazolam is effective in executions and is effective at rendering someone unconscious and unable to feel pain during an execution. 

Critics say Midazolam tends to cause of those being executed to convulse, gasp, cough and wheeze during executions, something they say may be the result of excess fluid entering the lungs, resulting in a drowning effect. Midazolam is a sedative, but not a painkiller, they argue, and if the person being executed is not sufficiently anesthetized they will feel the drowning and burning sensation that would occur as their lungs filled with fluid. 

Midazolam has a checkered history as an effective execution drug.

In Ohio in 2014, a man named Dennis McGuire, who was on death row after being convicted in 1994 of the rape and murder of 22-year-old Joy Steward, choked and gasped before dying following a 24-minute execution. Ohio’s governor, John Kasich, a Republican, issued a three-year moratorium on executions following McGuire’s death. A federal judge in 2017 banned Ohio from conducting executions, ruling that its drug protocol — which included midazolam — was unconstitutional. The ban was overturned by an appeals court. 

In 2014 in Arizona, Joseph Wood, on death row for the 1989 killing of Debra Dietz and Eugene Dietz, “gasped and snorted” for almost an hour during a two-hour execution using midazolam as a sedative. The process went on so long that Wood’s attorneys filed a legal motion during the execution, seeking to stop it.

An Ohio coroner studied 27 autopsy reports of people executed with a drug cocktail including midazolam — 23 showed signs of pulmonary edema. 

Gilbert Postelle. Courtesy DOC.

Oklahoma is set to execute Gilbert Postelle on Thursday. Postelle, 35, was convicted and sentenced to death following the killing of four people in a mobile home park in 2005.

Barring a last-minute stay by the courts, Postelle will be the fourth person Oklahoma has executed under its new drug protocol. The long-awaited trial over Oklahoma’s death penalty protocol is set to begin Feb. 28.