I closed with him.
By the way he moved, I knew he was used to physical combat, but you can't win them all, and I had been in a lot of scraps when I had been younger. (Hadn't I?)
I stepped in while he was trying to decide whether to use the hypo on me or drop it to have his hands free. I stiff-handed him in the solar plexus and crossed my fist into the hollow of the apex arch of his jawbone. He dropped.
I gave him a kick at the base of his spine. He grunted and lay still.
There was a rapping on the door. "Doctor? Doctor?"
I searched through his pockets. He didn't have any keys. He didn't have any money or identification or a gun. He had a handkerchief and a ballpoint pen.
The receptionist had moved away from the door and was talking to somebody, in person or on the phone or intercom.
There wasn't any back door.
I went to the window. The city stretched out in an impressive panorama. On the street below, traffic crawled. There was a ledge. Quite a wide, old-fashioned ornamental ledge.