Not finished yet, but I may be off to a good start I think.
concrete, or, more punny, cement, the key ingredient in concrete (see next sentence).
I surround men on all sides
In the word "cement", "men" is surrounded on both sides by other letters.
I make them deaf
If you get concrete poured over you, you can't hear after it gets in your ears, but that would be the least of your problems.
and I escort them to oblivion
In cliche crime stories, people are often thrown into the river with their feet in concrete, leading them to oblivion.
and yet they love me
Sure, concrete builds houses and roads and cities. We'd be nowhere without it!
They have shed the blood of others to obtain me.
A bit far-fetched, but the story goes that people used to use blood to temper steel swords. Maybe that could also be done with the steel bars used for reinforced concrete.
I appear harmless and yet pierce those who approach me.
Reinforced concrete looks smooth on the outside, but all these sharp steel bars inside can pierce you if you're not careful.
Only come for me when all is hot and dry, or all will be lost.
If you step onto a concrete surface when it hasn't dried yet, you may sink into it and be lost.