Walking out of the execution chamber alive: the chemical violence of Tennessee's lethal injection

Christa Pike, 50, of Tennessee underwent the lethal injection process on September 30, yet became the only person on record with the U.S. Death Information Center to survive after being administered lethal injection drugs. According to ABC News, after being injected twice with pentobarbital, she was rushed from a maximum-security prison in Nashville to a hospital; her defense attorneys at one point believed she was brain-dead and could only be sustained by life support.

This failed execution in the American South has torn open the cracks in the "humane" narrative surrounding the U.S. death penalty system. Pentobarbital is a barbiturate sedative commonly used in animal euthanasia; in Australia it is better known by the brand name Nembutal and is referred to by euthanasia advocates as the "peaceful drug." Multiple U.S. death penalty states have used it as their drug of choice for injection over the past decade or more, on the grounds that it is "more humane" than firing squads or electrocution.

Behind the orderly procedure on paper lies the brutal collision between chemical violence and human physiology. According to ABC News, citing a U.S. Department of Justice review, pentobarbital can only dissolve in strong acid or strong alkali solutions, and when injected at "execution-level" doses, it is itself a highly alkaline substance with a pH close to that of household detergent. The review warned that the drug carries risks of "intense pain during injection" and "acute pulmonary edema," the mechanism being that the drug's high pH damages the blood vessels in the lungs, filling them with fluid and producing a "sensation of drowning" in the condemned.

The disparity in dosage further amplifies the risks. According to ABC News, Tennessee's execution protocol calls for two syringes delivering a combined 5 grams of pentobarbital, while the toxic dose recognized by the U.S. Food and Drug Administration is roughly 1 gram (1,000 milligrams). Andrew Crowe, associate professor of pharmacology at Curtin University, explained to ABC News the physiological consequences when the injection misses the vein: the drug and solution fail to be diluted into the bloodstream and instead linger in an environment with a pH of about 11, where they begin to dissolve tissue and blood vessels. "Before it is completely destroyed, any remaining pain receptors will send very intense signals to the brain," Crowe said. "Those pain receptors will fire wildly, causing extreme pain, and the local tissue injected with the alkaline solution will eventually necrotize."

By early October, Pike had woken in the hospital and was able to speak. Her defense attorney Randy Spivey described her condition at a press conference: "Christa has developed blood clots in one arm, she has pneumonia, and she is unable to swallow, so she has not yet eaten. Both of her arms are immobile and severely swollen; we don't know how much function her arms will recover, or whether they will recover at all." The legal team declined to disclose her long-term rehabilitation outlook. A photograph of an arm that circulated online was deemed too graphic for media publication.

Jonathan Brett, professor of toxicology at the University of New South Wales and a clinical toxicologist at the state's Poisons Centre, told ABC News that lethal injection depends on the drug entering the circulatory system "very rapidly." "If the drug doesn't go into the vein but into the surrounding tissue, the effects will set in more gradually," Brett said. "If it is unsuccessful, the condemned person will experience a period of cerebral oxygen deprivation — essentially equivalent to a severe stroke — which can cause severe disability and require long-term care."

Pike has been on death row for nearly thirty years since her conviction in 1996. She was 18 at the time when she was convicted of killing a fellow student, Colleen Slemmer. According to ABC News, experts speculate that in Pike's case the drug failed to enter the vein and instead entered the tissue surrounding it. Tennessee has yet to confirm whether it will attempt to execute her again.

Tennessee's execution protocol prescribes the syringe configuration, dosage and timing, but it does not prescribe what to do when the condemned person does not die, nor does it detail the process by which an overdose of pentobarbital causes death. When a state procedure officially described as "more humane" produces, for the first time, a condemned person who walks out of the execution chamber alive, the state government has yet to offer an answer for how to face that consequence.