Place the patient supine on a firm surface with his head at level or slightly lower than the level of heart. Immediately, clear the airway and start rescue breathing. In an unconscious patient the base of the tongue falls back to obstruct the airways. For this, combination of head tilt and chin lift should be employed to open the airways. In this method the flat of the hand is placed on the forehead and pressure is applied to tip the patient's head maximally backward.
Chin can be lifted forward with the other hand placing the fingertips under the mandible near the protruberance of the chin, bringing the chin forward while supporting the jaw. Oral cavity should be cleared of all secretions.
If after opening the airway child is still not breathing or having gasping respiration, rescue breathing should be started. Place your mouth over the mouth of the baby to make a tight seal. In infants, nose can also be included while in the older children nose can be pinched. Two slow breaths are delivered in succession each lasting for 1-1% second. This helps to check if there is any airway obstruction as well as helps in opening of collapsed alveoli. Amount of air deliveted should cause adequate rise in chest wall.
If chest wall does not rise, airway obstruction due to inflammatory swelling, mucous plug or foreign body should be suspected. In such a case, readjust at head tilt and lifting of chin and repeat rescue breathing with greater pressure and volume; if still not successful, suspect foreign body.