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Keep the person's head tilted back. Pinch the person's nostrils closed, using your thumb and forefinger. Cover the person's mouth tightly with your mouth. Keeping a tight seal over the person's mouth, slowly give two breaths ("rescue breaths"). Pause between each breath. Watch for the victim's chest to rise. If the chest does not rise, reopen the airway, check your seal on his mouth/nose and breathe harder. Turn the head slightly or tilt it back slightly more, then again try giving two breaths with a pause between. Begin chest compressions if the object is removed but the victim no longer has a pulse. To perform chest compressions: Ensure that the person is lying flat on the floor on a hard surface. Place the heel of one of your hands on the person's breastbone, right between her nipples. Place the heel of your second hand on top of the first. Lean directly over your hands. Start performing compressions. Push down with your hands at least 2 inches into the person's chest, then let the chest rise completely. You will have to push hard and fast. Count out 30 quick chest compressions. After 30 chest compressions, open the person's mouth again and look for a dislodged object. Pull it out if you can. Attempt a quick sweep again if no object is immediately seen. If you do not see the object, give two rescue breaths again, with a one second pause between each. If the person's chest is still not rising and falling, keep repeating the cycle of 30 chest compressions, then two rescue breaths, until emergency medical assistance arrives. If another person is with you, switch off with him every two cycles. CPR is exhausting. Do not attempt to continue CPR if you are too tired. Improper CPR is not helpful to the patient.
Prepare for rescue breathing. Begin breathing. Reposition the head if the person does not begin breathing. Start performing compressions. Stop and check to see if you can see the object causing the blockage. Continue the cycle until help arrives, if the person does not resume breathing.