I have reached chapter 12 "Trauma" in Hotline Miami, which is in the hospital. I believe this is the stealth level that has been mentioned by various reviews.
I can see what I think is the objective of the level in the top left corner of the map:
I've managed to sneak to the door that is visible on the right hand side of the screenshot, however, the door appears to be broken or locked, so I can't get across the corridor.
How do I progress from here? Or am I taking the wrong approach for this level?