Treatment.—As the immediate risk to life is from suffocation, it is usually necessary to perform tracheotomy at once. In fracture of the hyoid the fragments may be replaced by manipulation through the mouth, after which the head and neck are immobilised by a poroplastic collar.
Wounds—Cut-throat.—The most important variety of wound of the neck met with in civil practice is that known as “cut-throat”—an injury usually inflicted with suicidal, less frequently with homicidal intent.
Suicidal wounds are usually directed from left to right (if the patient is right-handed), and they run more or less obliquely from below upwards across the neck; the wound being deepest towards its left end, that is where the weapon enters, and gradually tailing off towards the right. In most cases the would-be suicide throws his head so far back at the moment of inflicting the wound, that the main vessels are carried backward under cover of the tense sterno-mastoid muscles, and so escape injury. The knife may even reach the vertebral column without damaging the contents of the carotid sheath.
Homicidal wounds are usually more directly transverse, and are of equal depth throughout. The main vessels are generally divided, the œsophagus and trachea opened into, and in some cases the vertebral canal is opened and the cord and its membranes injured.
Clinical Features.—The clinical features vary with the level of the wound and with its depth. In all cases the contraction of the platysma causes the wound to gape widely, and its edges tend to be turned in.
In a large proportion of suicidal attempts the patient only succeeds in inflicting one or more comparatively superficial wounds across the front of the neck. In many cases the hæmorrhage from these is trifling, but if the external jugular and other large superficial veins are divided, it may be fairly profuse, although it is seldom immediately fatal, unless the blood is sucked in to the wounded air-passage.
Occasionally, but rarely, the wound is made above the hyoid bone, and opens directly into the mouth. There may then be sharp hæmorrhage from the base of the tongue or from the lingual and external maxillary (facial) arteries or their branches in the submaxillary region, and asphyxia may result from the base of the tongue and the epiglottis falling back and obstructing the larynx.
The hyo-thyreoid membrane is frequently divided, and the pharynx thus opened. As the depressor muscles of the hyoid are divided, there is interference with deglutition and phonation, but respiration is not affected. In such cases the upper portion of the epiglottis is often cut off, and the base of the tongue, the tonsil or the soft palate may be injured. The lingual, external maxillary and superior thyreoid arteries, and the hypoglossal nerve are also liable to be divided at this level, but the main vessels of the neck usually escape. There is pain and difficulty in swallowing, and food and saliva tend to escape through the wound. Particles of food may pass into the air-passages and cause violent fits of coughing.
In more severe cases the knife enters the larynx or the trachea. Sometimes the thyreoid cartilage is divided—as a rule only partly—and the vocal cords are injured; in other cases the trachea is opened, or it may be completely cut across. The bleeding is serious, as the superior thyreoid arteries are usually damaged. If the common carotid and the internal jugular vein also are wounded, the hæmorrhage usually proves fatal. The fatal issue may be contributed to by blood entering the air-passages and causing asphyxia, or by air being sucked into the open veins and causing air embolism. The laryngeal branches of the vagus may be divided and paralysis of the larynx ensue.
In all cases there is more or less dyspnœa and persistent coughing. The voice is husky, and the patient can only express himself in a hoarse whisper. There is difficulty in swallowing, and the food may enter the trachea. When the external wound is small, there may be a considerable degree of emphysema of the cellular tissue.