Procedure for Lethal Injection (quoted from Wikipedia)
The condemned person is strapped onto a gurney; two intravenous cannulae ("IVs") are inserted, one in each arm. Only one is necessary to carry out the execution; the other is reserved as a backup in the event the primary line fails. A line leading from the IV line in an adjacent room is attached to the prisoner's IV, and secured so the line does not snap during the injections.
The arm of the condemned person is swabbed with alcohol before the cannula is inserted. The needles and equipment used are also sterilized. There have been questions about why these precautions against infection are performed despite the purpose of the injection being death. There are several explanations: cannulae are sterilized during manufacture, so using sterile ones is routine medical procedure. Secondly, there is a chance that the prisoner could receive a stay of execution after the cannulae have been inserted, as happened in the case of James Autry in October 1983 (he was eventually executed on March 14, 1984). Finally, it would be a hazard to prison personnel to use unsterilized equipment.
Following connection of the lines, saline drips are started in both arms. This, too, is standard medical procedure: it must be ascertained that the IV lines are patent, ensuring the chemicals do not mix in the IV lines and occlude the needle, preventing the drugs from reaching the subject. A heart monitor is attached so prison officials can determine when death has occurred.
The intravenous injection is usually a series of drugs given in a set sequence, designed to first induce unconsciousness followed by death through paralysis of respiratory muscles and/or by cardiac arrest through depolarization of cardiac muscle cells. The execution of the condemned in most states involves three separate injections (in sequential order):
Sodium thiopental or pentobarbital: ultra-short action barbiturate, an anesthetic agent capable of rendering the prisoner unconscious in a few seconds.
Pancuronium bromide: non-depolarizing muscle relaxant, causes complete, fast and sustained paralysis of the skeletal striated muscles, including the diaphragm and the rest of the respiratory muscles; this would eventually cause death by asphyxiation.
Potassium chloride: stops the heart, and thus causes death by cardiac arrest.
The drugs are not mixed externally as that can cause them to precipitate. Also, a sequential injection is key to achieve the desired effects in the appropriate order: administration of the pentobarbital essentially renders the inmate unconscious; the infusion of the pancuronium bromide induces complete paralysis, including that of the lungs and diaphragm rendering the inmate unable to breathe. The injection of a highly concentrated solution of potassium chloride could cause severe pain at the site of the IV line as well as along the punctured vein, but it will interrupt the electrical activity of the heart muscle and cause it to stop beating, bringing about the death of the inmate.
The intravenous tubing leads to a room next to the execution chamber, usually separated from the offender by a curtain or wall. Typically a prison employee trained in venipuncture inserts the needle, while a second prison employee orders, prepares and loads the drugs into the lethal injection syringes. Two other staff members take each of the three syringes and secure them into the IVs. After the curtain is opened to allow the witnesses to see inside the chamber, the condemned offender is then permitted to make a final statement. Following this, the warden will signal that the execution may commence, and the executioner(s) (either prison staff or private citizens depending on the jurisdiction) will then manually inject the three drugs in sequence. During the execution, the condemned's cardiac rhythm is monitored. Death is pronounced after cardiac activity stops. Death usually occurs within seven minutes, although the whole procedure can take up to two hours, as was the case with the execution of Christopher Newton on May 24, 2007. According to state law, if a physician's participation in the execution is prohibited for reasons of medical ethics, then the death ruling can be made by the state Medical Examiner's Office. After confirmation that death has occurred, a coroner signs the condemned’s death certificate.
In three states (Delaware, Illinois and Missouri) there is a lethal injection machine designed by Massachusetts-based Fred A. Leuchter that comprises two components: the delivery module and the control module.(Illinois has since abolished the death penalty.) Two staff members each have a station in which they key the machine on and depress two stations buttons to be ready in case of mechanical failure. Each person presses one station button on the console which travels to a computer which starts all three injections electronically. The computer then deletes who actually started the syringes so that participants are not aware if their syringe contained saline or one of the drugs necessary for execution (to assuage guilt in a manner similar to the blank cartridge in execution by firing squad). The delivery module has eight syringes. The end syringes containing saline, syringes 2, 4, 6 containing the lethal drugs for the main line and syringes 1, 3, 5 containing the injections for the back-up line. The system was used in New Jersey before the abolition of the death penalty in 2007. Illinois previously used the computer, and Missouri and Delaware use the manual injection switch on the delivery panel.
In 2011, after pressure by activist organizations, the manufacturers of sodium thiopental and pentobarbital halted supply of the drugs to U.S. prisons performing lethal injections and required all resellers to do the same.
