Greg helped him into the wheelchair and put on his jacket and they set off. "Noone knows anything about all of this, by the way. I didn't tell anyone where I was going." he admitted, though he had actually thought Sherlock must have realized that the thread about reinforcements had been a total bluff. Or maybe the roughed up, bleeding and tired Sherlock had not picked up on that bit. Because Greg really never had thought himself to be that good a liar.
Surprising was though, that Sherlock had admitted to being aware of how he was treating people and that he knew how people reacted to it. Except for being horribly annoyed most of the time, Lestrade had never actually minded it that much. For him, that was just how Sherlock was. And as far as he knew, Sherlock seldomly treated anyone the way he did because he wanted to hurt them, with a few exceptions of course, of whom at least two where on Gregs team. 
They headed out of the hospital, not being questioned by anyone, which was probably a little worrying in concern of the security of the hospital. But even if anyone had tried to stop them, you could get away with almost anything if you had a police badge. They left the wheelchair by the entrance and he helped Sherlock up, carefully putting the uninjured arm around his neck and holding on to his waist. "Tell me if the position hurts. I parked right over there." he said, nodding toward his car a few meters away.
The drive to Baker Street passed mostly in silence. Greg couldn't come up with any goof topic, especially since he had noticed back in the hospital already, that Sherlock was actually still very tired.