Ohio Inmate Claiming Obesity

I didn't know that there was a "weight limit" for lethal injections, if that is your given death sentence. There is a man in the Ohio State Prison who is claiming that he is too obese and that his veins are too hard to find because of his size. He says that it will be too hard to put the intravenous into his arm. To me that seems ridiculous and that he's just trying to find a way to prolong his death sentence. I've never heard of someone not being able to serve their death sentence because of their weight. He was placed in jail for raping and killing two college girls over 22 years ago, while he was on leave from the military. He and an accomplice also carved an 'x' into their abdomens after they killed the two girls.