Tetanus is a toxic disease of the nervous system caused by the exotoxin of tetanus bacillus. The disease is characterized by progressive development of muscle ankylosis with episodic exacerbation, and the mortality rate is about 10-40% if not treated in time. Pathogenesis] Tetanus is caused by the infection of tetanus bacillus. Tetanus bacillus is a gram-positive germ cell anaerobic bacterium, widely dispersed in the soil, feces also contain the bacterium. Invasion of the wound by tetanus bacilli alone is not sufficient to cause the disease; other bacteria, or foreign objects such as pieces of wood, glass, etc., must be present at the same time. Tetanus bacilli breed only in anaerobic wounds and do not spread elsewhere, but the bacterium produces an exotoxin that can cause neurotoxicity. When the toxin acts on the brainstem and the crural medulla, it produces specific muscle spasms due to the contraction of both the active and antagonist muscles. Clinical manifestations] The incubation period is variable, usually 7-8 days. In patients who have received antitoxin prophylactic vaccination, it may extend to several weeks. Individuals can be as short as 1~2 days. Patients often have a prodromal period of restlessness and irritability. The first motor symptom is often clenching of the teeth, which may be followed or preceded by tonus of the neck muscles. Within hours, the spasm spreads to other muscles. Facial muscle spasms may cause a spasmodic “bitter smile” with lip retraction or inward contraction of the corners of the mouth. Examination reveals tonus in the muscles of the limbs and trunk, possibly with mild corns, tonus of the abdominal wall muscles, and the lower limbs are often more severely impaired than the upper limbs, and are more often fixed in an extended position. When the disease continues to progress, the generalized persistent ankylosis is exacerbated by episodes of severe spasm-like pain. The seizures are often characterized by corrugator spasms, and spasms of the laryngeal and inspiratory muscles result in dyspnea and profuse sweating. These convulsive seizures can be triggered by external stimuli, such as during an attempt to feed the patient. During the interictal period, generalized muscle tonus persists, tendon reflexes are hyperactive, and the patient remains conscious throughout. Patients may die from asphyxia due to convulsive seizures, or from heart failure due to frequent and intense myoclonic spasms. Hypothermia is not uncommon in this disease; the presence of hyperthermia is a sign of exacerbation, and the temperature may continue to rise even after death. Uremia, hypotension and gastric dilatation are most likely to occur between 7 and 14 days, and laryngospasm, apnea, motor paralysis and pneumonia are all critical complications. In well-traveled patients, the frequency and severity of myoclonic episodes gradually decrease, but generalized tonus often persists for several weeks, and clenching of the teeth is often the last symptom to disappear. There are less common clinical types (1) Localized. The first symptom of this type of tetanus is localized spasm of the muscles adjacent to the trauma, from which persistent or intermittent spasm spreads to the adjacent muscles, and the severity can develop to the limbs, head and trunk. (2) Head tetanus. It develops after trauma to the head, neck or face. There is often paralysis of the facial muscles on the injured side, accompanied by spasm of the facial muscles on the opposite side, which is easily combined with clenching of the teeth and pharyngeal spasm. When the trauma involves the orbit, ptosis and paralysis of the extraocular muscles are seen on one or both sides. Head tetanus can remain limited or become generalized, with a high mortality rate. (3) Visceral tetanus. This type is caused by abdominal trauma, which can involve the muscles innervated by the medulla oblongata and the muscles of the whistle at an early stage, accompanied by significant autonomic nervous system dysfunction such as tachycardia, arrhythmia, peripheral vasoconstriction, profuse sweating, high fever, etc. Due to the sympathetic hyperfunction, tetanus may become generalized. Due to sympathetic hyperfunction, the amount of carbon dioxide discharged in the whistle and the excretion of catecholamines in the urine are increased. (4) Neonatal tetanus. The fetus is infected during labor and delivery (e.g., skin and mucous membrane injury, umbilical cord wound infection, etc.), and the disease develops about 7 days after birth. However, spontaneous clenching of teeth is generally rare, and only occurs reflexively when the hand presses the lower jaw during the examination. [Diagnosis] According to the history of traumatic infection, the early appearance of clenching of teeth, as well as spasm of skeletal muscles in all parts of the body, the neck is straight, the angle of the arches and difficulty in whistling, etc., it should not be difficult to make a diagnosis of tetanus. Differential Diagnosis] 1. Strychnine Poisoning Convulsions in strychnine poisoning are superficially similar to those in tetanus, but they occur more rapidly. In addition, the reflex excitation of the convulsions is evident at the beginning, whereas in tetanus it is a late manifestation. Another difference from tetanus is that in strychnine poisoning the muscles are completely flaccid between attacks, the upper extremities are often more severe than the lower, and the history of the poisoning is known. 2, rabies rabies is also easy to confuse with tetanus, but rabies patients do not have teeth, fear of water and swallowing difficulties are the most prominent symptoms. In addition, in the interictal period, the muscles can be completely flaccid, and almost all of them have been bitten by rabid dogs. 3, the rest of the lesser diseases are head and face dystonia, facial muscle spasm, temporal joint lesions, and so on. 【Treatment】 Patients must be isolated care, minimize external stimuli, keep it quiet. 1, the treatment of antitoxin tetanus antitoxin (TAT) can neutralize the toxin in the process of being absorbed, in order to ensure the efficacy of the treatment must be given a large dose of antitoxin. Intravenous infusion of 50,000U tetanus antitoxin on the day of admission, and thereafter daily intravenous infusion of 10,000U, the total amount can be up to 200,000U. 2, anti-spasmodic treatment The effective treatment of severe tetanus is to eliminate muscle spasm. It can be applied with 15mg of chloroquat chloride, and the total amount can be 150-650mg per day, and supplemented with positive pressure artificial whistling. Chlorpromazine 50~100mg can be injected intramuscularly every 4~6 hours; or Valium (imipramine) 10mg~15mg can be injected intravenously, depending on the condition, it can be applied many times. 3.Anti-infection treatment Use antibiotics to prevent lung infection Penicillin 10～40 million U/d, divided into intravenous drip. 4.Keep the respiratory tract unobstructed Those who have a lot of secretions in the respiratory tract and have difficulty in discharging them, those who have spasm for a long time or those who have suffocated should be tracheotomized as early as possible, and attention should be paid to the suctioning of sputum. 5, supplement nutrition, water and electrolyte nutrition and water, electrolyte balance must be paid attention to. Especially when the teeth and pharyngeal spasm often make it difficult to eat, it is necessary to use liquid diet for nasal feeding, or give intravenous high nutrition. Wound treatment Flush the wound with 3% hydrogen perchloride solution to keep the drainage open. The healed wound should be incised if there is any foreign body or inflammatory mass. Prevention: 1. All open wounds need early and thorough debridement. 2. Promote the new method of delivery and correctly handle the umbilical cord. Passive immunization 1500U of tetanus antitoxin should be injected intramuscularly as early as possible after the injury, and if the trauma is serious, it can be repeated intramuscularly for 1 time after 1 week. Intradermal allergy test should be done before injection, and positive people should be desensitized before application. Active immunization is the most reliable method. Subcutaneous injection of tetanus toxoid in 3 times, 0.5~1ml each time, with an interval of 6~8 weeks, and then reinforce the injection once a year for better effect.