A cricothyrotomy (also called thyrocricotomy, cricothyroidotomy, inferior laryngotomy, intercricothyrotomy, coniotomy or emergency airway puncture) is an emergency incision through the skin and cricothyroid membrane to secure a patient's airway during certain emergency situations, such as an airway obstructed by a foreign object or swelling, a patient who is not able to breathe adequately on their own, or in cases of major facial trauma which prevent the insertion of an airway through the mouth. A cricothyrotomy is usually performed by emergency physicians, trauma surgeons, or paramedics as a last resort when control of the airway by usual means (an endotracheal tube through the mouth) have failed or are not feasible. This technique is considered easier and faster than a tracheostomy, but is only used when oral or nasal intubation is not possible. This procedure does not require manipulation of the cervical spine. However, it does require special training and authorization from local medical direction prior to being performed, depending on local medical protocols.

From http://en.wikipedia.org/wiki/Cricothyrotomy