David McGuire, an Ohio inmate charged with raping and killing a woman in 1989, is set to be killed by lethal injection by an untried method that could cause him to painfully suffocate, according to the Associated Press.

During a two-day hearing on Ohio's lethal drug process, McGuire's lawyer stated he will suffer from "air hunger," which will cause extreme pain and terror as the inmate struggles to breath, according to David Waisel, a Harvard Medical School professor who is testifying in the case, the AP reported.

According to McGuire's attorney, he "will experience the agony and terror of air hunger as he struggles to breathe for five minutes after defendants intravenously inject him with the execution drugs," the AP reported.

Waisel added that due to the inmates sleep apnea, he is more likely to be suffocated, the AP reported.

"Mr. McGuire is at a substantial risk of experiencing the terror of air hunger during the first five minutes of the execution," Waisel said, according to the AP. "Air hunger is a horrible feeling, it's the inability to get your breath."

McGuire, is 53-years-old and was sentenced to death for raping and stabbing a 22-year-old pregnant woman to death in Pebble County, according to the AP.

The two drugs to be used are midazolam, a sedative, and hydromorphone, a painkiller, in a method that has been legal in Ohio's execution process since 2009, but has never been carried out, the AP reported. The combination of drugs was chosen because of lack of lethal injection drugs.

Attorney Thomas Madden stated during the hearings that although the U.S. constitution prohibits a death penalty that used cruel and unusual punishment, it does not state the execution needs to be painless, the AP reported.

"You're not entitled to a pain-free execution," attorney Thomas Madden told presiding Judge Gregory Frost, according to the AP. Madden added the state has proof from anesthesiology experts to argue the inmate will not experience the effects of air hunger.

In the past, courts have rejected the claim that lethal injection drugs cause severe pain, the AP reported. Because the courts have rejected the claim in the past, the state is now saying McGuire cannot challenge their use in an effort for stop or postpone his execution.

In a court filing, lawyers for the state said "There is no excuse for not raising this claim years ago, much less presenting it for the first time in an eleventh-hour stay of execution, the AP reported.