Autopsies of the four men executed by Oklahoma between October 2021 and February 2022 show that all four prisoners had excess fluid in their lungs, giving additional credence to death-row prisoners’ claims that Oklahoma’s lethal-injection process will subject them to an unconstitutionally torturous death.

The autopsy report for Gilbert Postelle, obtained by Oklahoma Watch through a public records request and published May 25, 2022, found that Postelle experienced pulmonary edema with “frothy parenchymal fluid” during his February 17, 2022 execution. Pulmonary edema is an abnormal build-up of fluid in the lungs. The report, prepared by Medical Examiner Ross Miller, M.D., indicated that Postelle’s lungs had a combined weight of 1,220 grams, making them between a quarter to a third larger than the average adult lung size of between 900 and 1,000 grams.

Medical experts for the prisoners testified during a six-day federal trial in February and March 2022 on the constitutionality of Oklahoma’s execution protocol that frothing could only occur if “the prisoner is alive and breathing” when the edema occurred. The autopsy results from the executions of John Grant and Bigler Stouffer, they said, indicated that the men experienced severe pain from pulmonary edema that occurred while they were being put to death. John Grant’s lungs weighed 1,390 grams, and Stouffer’s lungs weighed 1,510 grams. John Grant also suffered intramuscular bleeding of his tongue, which is commonly found in fire fatalities, drowning victims, and victims of asphyxiation.

Autopsy results for Donald Grant, who was executed on January 27, 2022, and Postelle were not available at the time of the trial. Donald Grant’s autopsy also indicated that his “lung tissue displays edema and congestion.” According to the autopsy, Donald Grant’s lungs weighed 880 grams.

The findings from the autopsies suggest that the men may have experienced severe pain from the fluid building up in their lungs shortly after the lethal injection executions began. The news of Postelle’s autopsy comes while the parties await a decision from U.S. District Court Judge Stephen Friot on the constitutionality of the state’s execution protocol.

An NPR analysis of autopsies of more than 200 prisoners executed by lethal injection found that pulmonary edema was noted in 84% of the autopsies and was even more ubiquitous in multi-drug executions involving the sedative drug midazolam. Oklahoma’s three-drug execution protocol uses a combination of midazolam, the paralytic drug vecuronium bromide, and the drug potassium chloride to stop the prisoner’s heart.

Dr. Mark Edgar, a pathologist and autopsy director at the Mayo Clinic in Florida, who reviewed more than 30 autopsies of prisoners executed by death penalty protocols that employed midazolam, testified that 27 of those prisoners had experienced “severe pulmonary edema,” which would produce sensations of “doom, panic, drowning, and asphyxiation.” Oklahoma State University pharmacology professor Dr. Craig Stevens testified that midazolam has a “ceiling effect” above which it loses any additional sedative effect. The drug, he testified, lacks the pharmacological properties necessary to adequately render prisoners unconscious and insensate before they are paralyzed by the second drug and subjected to what he called the “burning fire” sensation of the potassium chloride. Dr. Gail Van Norman, professor of anesthesiology and pain medicine at the University of Washington Medical School, testified to a “virtual medical certainty” that the four prisoners executed under Oklahoma’s current protocol “experienced extreme pain and suffering.”

Prosecutors argued that the evidence of pulmonary edema did not prove that the executions were torturous. Dr. Joseph F. Antognini, an anesthesiologist and professor at the University of California at Davis who has testified for prosecutors in numerous lethal-injection cases, disputed that the fluid build-up occurred while the prisoners were conscious and argued that the dosage of midazolam administered to the prisoners “would render somebody incapable of experiencing or feeling pain from a noxious stimulus.”

“Even if inmates were conscious of the pulmonary edema later found in their autopsies,” state prosecutors argued in their post-trial briefing, “the evidence is still insufficient to show they were sure or very likely in severe pain.”