During an interview with Howard Stern in 2008, Trump explained his aversion to blood with a story about when he saw an elderly man fall during a charity ball at Mar-a-Lago.

I was at Mar-a-Lago and we had this incredible ball, the Red Cross Ball, in Palm Beach, Florida. And we had the Marines. And the Marines were there, and it was terrible because all these rich people, they’re there to support the Marines, but they’re really there to get their picture in the Palm Beach Post…

 

So you have all these really rich people, and a man, about 80 years old—very wealthy man, a lot of people didn’t like him—he fell off the stage. So what happens is, this guy falls off right on his face, hits his head, and I thought he died. And you know what I did? I said, ‘Oh my God, that’s disgusting,’ and I turned away. I couldn’t, you know, he was right in front of me and I turned away. I didn’t want to touch him… he’s bleeding all over the place, I felt terrible. You know, beautiful marble floor, didn’t look like it. It changed color. Became very red. And you have this poor guy, 80 years old, laying on the floor unconscious, and all the rich people are turning away. ‘Oh my God! This is terrible! This is disgusting!’ and you know, they’re turning away. Nobody wants to help the guy. His wife is screaming—she’s sitting right next to him, and she’s screaming.

 

What happens is, these 10 Marines from the back of the room… they come running forward, they grab him, they put the blood all over the place—it’s all over their uniforms—they’re taking it, they’re swiping [it], they ran him out, they created a stretcher. They call it a human stretcher, where they put their arms out with, like, five guys on each side. I was saying, ‘Get that blood cleaned up! It’s disgusting!’ The next day, I forgot to call [the man] to say he’s OK. It’s just not my thing.”

The Daily Beast – The Time Donald Trump Turned Away in Disgust While a Man Was Bleeding to Death in Front of Him
Metro – Trump once turned away in disgust when he saw a man bleeding to death on the floor