Different circuit but: The 6th U.S. Circuit Court of Appeals in Cincinnati has rejected a three-drug lethal injection process in Ohio because, in part, use of the anesthetic midazolam is unconstitutional.

The appeals court upheld a lower court ruling that use of the drug was inhumane. The judge wrote that the three-drug Ohio protocol, similar to that used in Arkansas, creates a "substantial risk of serious harm"or an "objectively intolerable risk of harm."

The appeals court wrote:

The district court found that Plaintiffs were likely to succeed on their claim that the use of midazolam as the first drug in a three-drug protocol creates a substantial risk of severe pain. There is no dispute that the suffocation caused by the paralytic and the intense burning sensation caused by potassium chloride [also used in Arkansas] are excruciatingly painful, just as in Baze it was ‘uncontested that ... there is a substantial, constitutionally unacceptable risk of suffocation from the administration of pancuronium bromide and pain from the injection of potassium chloride’ if a proper dose of an effective anesthetic is not administered first. This case, like Baze, ‘hinges on’ the efficacy of the first drug in the three-drug protocol.

Arkansas uses midazolam as the first drug, followed by the paralytic agent pancuronium bromide and then by potassium chloride.  Inmates scheduled to die here are questioning its use, particularly in a hurryup schedule of eight state killings over 10 days.  Gov. Asa Hutchinson speeded the execution process because the state supply of midazolam expires at the end of the month.

The Death Penalty Information Center provides this summary on the drug:

Four states have used midazolam as the first drug in the three-drug protocol: Florida, Oklahoma, Alabama, and Virginia. Oklahoma used midazolam in the botched execution fo Clayton Lockett in April 2014, and Lockett died after the procedure was halted. Alabama's use of midazolam in the execution of Ronald Smith in December 2016, resulted in nearly fifteen minutes of Smith heaving and gasping for breath. Arkansas intends to use midazolam in the three-drug protocol in carrying out executions in April 2017. In January 2017, Florida abandoned its use of midazolam as the first drug in its three-drug protocol and replaced it with etomidate. Two states have used midazolam in a two-drug protocol consisting of midazolam and hydromorphone: Ohio (Dennis McGuire) and Arizona (Joseph Wood). Both of those executions, which were carried out in 2014, were prolonged and accompanied by the prisoners' gasping for breath. After its botched execution of McGuire, Ohio abandoned its use of midazolam in a two-drug protocol, but then in October 2016 decided to keep midazolam in a three-drug protocol. In December 2016, Arizona abandoned its use of midazolam in either a two-drug or a three-drug protocol. Three states have, at some point, proposed using midazolam in a two-drug protocol (Louisiana, Kentucky, and Oklahoma) but none of those states has followed through with that formula. Some states have proposed multiple protocols. Missouri administered midazolam to inmates as a sedative before the official execution protocol began.

The Ohio court noted that it had more evidence about use of the court than in earlier cases, particularly in Oklahoma, where courts said they didn't have enough information to be sure about midazolam.