The frequent swallowing movements of comatose patients are due to the shallow degree of coma and the existence of the gag reflex, which is stimulated by saliva to make involuntary swallowing movements.
The ability of a comatose patient to make swallowing movements indicates a shallow coma. Such patients may also retain some simple reflexes, such as the gag reflex. Swallowing occurs when the throat is stimulated by saliva or other stimuli. This is a conditioned reflex, of which the patient is not aware and is not actively trying to swallow.
Swallowing and coughing are simple reflexes, and they are also a mechanism of self-protection for our body. If the patient is in a deep coma, all simple reflexes will disappear and the patient will not swallow. In this case, it is easy for oral secretions or food to block the airway, leading to choking.