The process which results from an obstruction, situated in the larynx (see AIR PASSAGES), to breathing. It may occur as the result of disease causing swelling round the glottis (the entrance to the larynx), or of some nervous disorders that interfere with the regulation of the muscles which open and shut the larynx. Generally, however, it is due to the irritation of a piece of food or other substance introduced by the mouth, which provokes coughing but only partly interferes with breathing. As the mucous membrane lining the upper part of the latter is especially sensitive, coughing results in order to expel the cause of irritation. At the same time, if the foreign body is of any size, lividity of the face appears, due to partial suffocation (see ASPHYXIA).
The choking person should take slow, deep inspirations, which do not force the particle further in (as sudden catchings of the breath between the coughs might), and which produce more powerful coughs. If the coughing is weak, one or two strong blows with the palm of the hand over either shoulder blade, timed to coincide with coughs, aid the effect of the coughing. If this is ineffective, the HEIMLICH MANOEUVRE may be used. This involves hugging the person from behind with one's hands just under the diaphragm. A sudden upward compressive movement is made which serves to dislodge any foreign body. In the case of a baby, sit down with left forearm resting on thigh. Place the baby chest-down along the forearm, holding its head and jaw with the fingers and thumb. The infant's head should be lower than its trunk. Gently deliver three or four blows between the shoulder blades with the free hand. The resuscitator should not attempt blind finger sweeps at the back of the mouth; these can impact a foreign body in the larynx.
If normal breathing (in adult or child) cannot be quickly restored, seek urgent medical help. Sometimes an emergency TRACHEOSTOMY is necessary to restore the air supply to the lungs.