Ok, watch the scene and press triangle as fast as you can when prompted. You'll have the triangle sequence 3 times before Snake passes out. Once you regain control, check the mirror next to the bed and press the button to have Snake take out a Jigsaw. When the soldier in front of the door leaves, approach it and use the
Alternate between the L and R buttons as they flash, otherwise you'll make noise and alert the guards, ending the mission. Once you've broken the lock, stay away from the door and wait for the guard to come and then go. Open the door and hide so that you can take care of the soldier patrolling your cell first.
Now go west and in this hallway you'll find 2 more soldiers, one patrolling up and down and the other one stays around in the corner. As the patrolling one goes south take care of the other soldier and then take care of the patrolling one. Enter the door at the northwest corner of the area to find *Ration 5 x3 . Now open your map and you'll see 3 adjacent rooms on the left side of the middle structure. Go inside the deepest room and use the control panel. Open the door and release the shackles of the prisoners.
Now exit and in the hallway where the 2 soldiers are, go to the southwestern corner and enter the little room to find *Fulton Recovery System 5 x5 . Now move east and you'll see a POW inside a cell. Open it and FRS her. Now proceed southeast into the next area... which is not in this mission.