There are two simple but radical means to bring the laptop out of "sleep." If you haven't already, try to begin with a brief press on the power button of the laptop, typically, any computer then "wakes up". If not, press and hold the power button for a few seconds. Usually this is enough to hard shut down the laptop. Pressing should lead to its inclusion.
The second method, though trivial, but it works flawlessly in all cases. Turn the laptop to get to the latch that holds the battery in the notebook. Move it to the Open position and pull the battery. After a few seconds, insert it and return the laptop to its original position and press the power button, that will certainly make him come back to life.