Last�Wednesday afternoon, convicted murderer Joseph Wood was executed in Arizona by lethal injection. The first drug was administered at 1:52pm.� Wood, however,�did not die until nearly two hours later, after witnesses said that he "gasped and struggled to breathe" for an hour and 40 minutes. The drugs administered were midazolam (a sedative made infamous as one of the drugs given to Michael Jackson by Dr. Conrad Murray) and hydropmorphone, a pain-killer and respiratory depressant. According to the Death Penalty Information Center, nearly one-third of the executions using Midazolam have had "extremely troubling problems", including cases where the prisoner appeared to fall asleep but then started moving again. This was the first time these two drugs were used in combination for an execution in Arizona. The trio of drugs traditionally used for lethal injection - sodium thiopental, pancuronium bromide and potassium chloride - have been in short supply since 2009, forcing states to develop new cocktails of lethal drugs for executions. The result, in Wood's case and in several others this year, has been executions that take hours instead of 15 minutes, and appear to cause�pain and discomfort during the execution process.