Tetanus

Background

Tetanus is characterized by an acute onset of hypertonia, painful muscular contractions (usually of the muscles of the jaw and neck), and generalized muscle spasms without other apparent medical causes. Despite widespread immunization of infants and children since the 1940s, tetanus still occurs in the United States. Currently, tetanus primarily affects older adults because of their higher rate of being unvaccinated or of being inadequately vaccinated. The image below illustrates tetanus cases in the United States from 1947-2012.

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Reported number of tetanus cases in the United States from 1947-2012. Image from National Notifiable Disease Surveillance System (NNDSS), Centers for ....

See Pediatric Vaccinations: Do You Know the Recommended Schedules?, a Critical Images slideshow, to help stay current with the latest routine and catch-up immunization schedules for 16 vaccine-preventable diseases.

Tetanus may be categorized into the following 4 clinical types:

• Generalized tetanus
• Localized tetanus
• Cephalic tetanus
• Neonatal tetanus

Approximately 50-75% of patients with generalized tetanus present with trismus (“lockjaw”), which is the inability to open the mouth secondary to masseter muscle spasm. Nuchal rigidity and dysphagia are also early complaints that cause risus sardonicus, the scornful smile of tetanus, resulting from facial muscle involvement.^{[1, 2]}

As the disease progresses, patients have generalized muscle rigidity with intermittent reflex spasms in response to stimuli (eg, noise, touch). Tonic contractions cause opisthotonos (ie, flexion and adduction of the arms, clenching of the fists, and extension of the lower extremities). During these episodes, patients have an intact sensorium and feel severe pain. The spasms can cause fractures, tendon ruptures, and acute respiratory failure.

Patients with localized tetanus present with persistent rigidity in the muscle group close to the injury site. The muscular rigidity is caused by a dysfunction in the interneurons that inhibit the alpha motor neurons of the affected muscles. No further central nervous system (CNS) involvement occurs in this form, and mortality is very low.

Cephalic tetanus is uncommon and usually occurs after head trauma or otitis media. Patients with this form present with cranial nerve (CN) palsies. The infection may be localized or may become generalized.^[3]

Neonatal tetanus (tetanus neonatorum) is a major cause of infant mortality in underdeveloped countries but is rare in the United States. Infection results from umbilical cord contamination during unsanitary delivery, coupled with a lack of maternal immunization. At the end of the first week of life, infected infants become irritable, feed poorly, and develop rigidity with spasms. Neonatal tetanus has a very poor prognosis.^{[4, 5]}

Although at present, tetanus is rare, it has not been eradicated, and early diagnosis and intervention are lifesaving. Prevention is the ultimate management strategy for tetanus.

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Pathophysiology

Clostridium tetani is an obligate, anaerobic, motile, gram-positive bacillus. It is nonencapsulated and forms spores that are resistant to heat, desiccation, and disinfectants. Since the colorless spores are located at one end of the bacillus, they cause the organism to resemble a turkey leg. They are found in soil, house dust, animal intestines, and human feces. Spores can persist in normal tissue for months to years.

To germinate, the spores require specific anaerobic conditions,^[6] such as wounds with low oxidation-reduction potential (eg, dead or devitalized tissue, foreign body, active infection). Under these conditions, upon germination, they may release their toxin. Infection by C tetani results in a benign appearance at the portal of entry because of the inability of the organism to evoke an inflammatory reaction unless coinfection with other organisms develops.

When the proper anaerobic conditions are present, the spores germinate and produce the following 2 toxins:

• Tetanolysin – This substance is a hemolysin with no recognized pathologic activity
• Tetanospasmin – This toxin is responsible for the clinical manifestations of tetanus^[7] ; by weight, it is one of the most potent toxins known, with an estimated minimum lethal dose of 2.5 ng/kg body weight

Tetanospasmin is synthesized as a 150-kd protein consisting of a 100-kd heavy chain and a 50-kd light chain joined by a disulfide bond.^[8] The heavy chain mediates binding of tetanospasmin to the presynaptic motor neuron and also creates a pore for the entry of the light chain into the cytosol. The light chain is a zinc-dependent protease that cleaves synaptobrevin.^[9]

After the light chain enters the motor neuron, it travels by retrograde axonal transport from the contaminated site to the spinal cord in 2-14 days. When the toxin reaches the spinal cord, it enters central inhibitory neurons. The light chain cleaves the protein synaptobrevin, which is integral to the binding of neurotransmitter containing vesicles to the cell membrane.

As a result, gamma-aminobutyric acid (GABA)-containing and glycine-containing vesicles are not released, and there is a loss of inhibitory action on motor and autonomic neurons.^[9] With this loss of central inhibition, there is autonomic hyperactivity as well as uncontrolled muscle contractions (spasms) in response to normal stimuli such as noises or lights.

Once the toxin becomes fixed to neurons, it cannot be neutralized with antitoxin. Recovery of nerve function from tetanus toxins requires sprouting of new nerve terminals and formation of new synapses.

Localized tetanus develops when only the nerves supplying the affected muscle are involved. Generalized tetanus develops when the toxin released at the wound spreads through the lymphatics and blood to multiple nerve terminals. The blood-brain barrier prevents direct entry of toxin to the CNS.

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Etiology

Tetanus spores may survive for years in some environments and are resistant to disinfectants and to boiling for 20 minutes. However, vegetative cells are easily inactivated and are susceptible to several antibiotics.

Tetanus can be acquired outdoors as well as indoors. The source of infection usually is a wound (approximately 65% of cases), which often is minor (eg, from wood or metal splinters or thorns). Frequently, no initial medical treatment is sought. Chronic skin ulcers are the source in approximately 5% of cases. In the remainder of cases, no obvious source can be identified.

Tetanus can also develop as a complication of chronic conditions such as abscesses and gangrene. It may infect tissue damaged by burns, frostbite, middle ear infections, dental or surgical procedures, abortion, childbirth, and intravenous (IV) or subcutaneous drug use. In addition, possible sources not usually associated with tetanus include intranasal and other foreign bodies and corneal abrasions.

Underimmunization is an important cause of tetanus. Tetanus affects nonimmunized persons, partially immunized persons, or fully immunized individuals who do not maintain adequate immunity with periodic booster doses.

Only 12-14% of patients with tetanus in the United States have received a primary series of tetanus toxoid. During 1998-2000, only 6% of all patients with tetanus were known to be current with tetanus immunization, with no fatal cases reported among this group.^[10] Surveillance data from this period revealed the following:

• In 73% of patients with tetanus in the United States, tetanus occurred after an acute injury, including puncture wounds (50%), lacerations (33%), and abrasions (9%)
• Stepping on a nail accounted for 32% of the puncture wounds
• Tetanus was found to occur in burn victims; in patients receiving intramuscular injections; in persons obtaining a tattoo; and in persons with frostbite, dental infections (eg, periodontal abscesses), penetrating eye injuries, and umbilical stump infections
• Other reported risk factors included diabetes, chronic wounds (eg, skin ulcers, abscesses, or gangrene), parenteral drug abuse, and recent surgery (4% of US cases)
• During 1998-2000, 12% of patients with tetanus in the United States had diabetes (with mortality, 31%), compared with 2% during 1995-1997; of these patients, 69% had acute injuries and 25% had gangrene or a diabetic ulcer
• The median time interval between surgery and onset of tetanus was 7 days
• Tetanus was reported after tooth extractions, root canal therapy, and intraoral soft tissue trauma

Worldwide risk factors for neonatal tetanus include the following:

• Unvaccinated mother, home delivery, and unhygienic cutting of the umbilical cord increase susceptibility to tetanus
• A history of neonatal tetanus in a previous child is a risk factor for subsequent neonatal tetanus
• Potentially infectious substances applied to the umbilical stump (eg, animal dung, mud, or clarified butter) are risk factors for neonates

Immunity from tetanus decreases with advancing age. Serologic testing for immunity has revealed a low level among elderly individuals in the United States. Approximately 50% of adults older than 50 years are nonimmune because they never were vaccinated or do not receive appropriate booster doses. The prevalence of immunity to tetanus in the United States exceeds 80% for persons aged 6-39 years but is only 28% for those older than 70 years.

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Epidemiology

United States statistics

Because of the widespread use of tetanus immunizations, the reported incidence of tetanus in the United States has declined substantially since the mid 1940s.

From 2001-2008, 233 cases of tetanus were reported in the United States, meaning a 95% reduction since 1947. Deaths from the disease had decreased by 99% since that year. The case mortality rate was 13.2%. Tetanus cases among Hispanics were approximately twice that among non-Hispanics, attributed to an increased rate of injection drug use among Hispanic patients. In the group of patients with known vaccination status, 40.2% had received no doses of tetanus toxoid; 15.4% of 195 patients had diabetes, and 15.3% of 176 were intravenous drug abusers. In the 51 individuals with an acute wound in whom adequate information was available, 96.1% had not received appropriate prophylaxis.^[11]

All 50 states require that children be vaccinated before being admitted to public schools. More than 96% of children have received 3 or more diphtheria and tetanus toxoids plus pertussis (DTP) vaccinations by the time they begin school.

Heroin users, particularly those who inject themselves subcutaneously, appear to be at high risk for tetanus. Quinine is used to dilute heroin and may support the growth of C tetani. The incidence of tetanus in people who use injection drugs increased 7.4% between 1991 and 1997, from 3.6% of all cases in 1991-1994 to 11% in 1995-1997. Injection drug users accounted for 15% of US tetanus cases from 1998 to 2000 (see the image below). Of the 19 people who used injection drugs and contracted tetanus in 1998-2000, only 1 reported an acute injury.

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Image from "Number of Tetanus Cases Reported Among Persons With Diabetes or Injection-Drug Use (IDU), by Age Group." Pascual FB, McGinley EL, Zanardi ....

From 1995-2000, 81% of cases in the United States were generalized tetanus, 15% were localized, and 3% were cephalic; 1 case of neonatal tetanus was reported.

International statistics

C tetani is found worldwide in soil, on inanimate objects, in animal feces, and, occasionally, in human feces. Tetanus is predominantly a disease of underdeveloped countries. It is common in areas where soil is cultivated, in rural areas, in warm climates, during summer months, and among males. In countries without a comprehensive immunization program, tetanus predominantly develops in neonates and young children.^{[12, 13]}

Developed nations have incidences of tetanus similar to those observed in the United States. For instance, only 126 cases of tetanus were reported in England and Wales from 1984-1992.^[14]

Although tetanus affects all ages, the highest prevalence is in newborns and young people.^[15] In 1992, an estimated 578,000 infant deaths were attributed to neonatal tetanus. In 1998, 215,000 deaths occurred, more than 50% of them in Africa. Tetanus is a target disease of the World Health Organization (WHO) Expanded Program on Immunization. Overall, the annual incidence of tetanus is 0.5-1 million cases. WHO estimated that in 2002, there were 213,000 tetanus deaths, 198,000 of them in children younger than 5 years.

Age-related demographics

Neonatal tetanus is rare, occurring most frequently in countries without comprehensive vaccination programs.

The risk for development of tetanus and for the most severe form of the disease is highest in the elderly population. In the United States, 59% of cases and 75% of deaths occur in persons aged 60 years or older. From 1980 through 2000, 70% of reported cases of tetanus in the United States were among persons aged 40 years or older. Of all these patients, 36% are older than 59 years and only 9% are younger than 20 years.

Sex-related demographics

Tetanus affects both sexes. No overall gender predilection has been reported, except to the extent that males may have more soil exposure in some cultures. In the United States from 1998 to 2000, the incidence of tetanus was 2.8 times higher in males aged 59 years and younger than in females in the same age range.

A difference in the levels of tetanus immunity exists between the sexes. Overall, men are believed to be better protected than women, perhaps because of additional vaccinations administered during military service or professional activities. In developing countries, women have an increased immunity where tetanus toxoid is administered to women of childbearing age to prevent neonatal tetanus.

Race-related demographics

Tetanus affects all races. From 1998 to 2000, the incidence of tetanus in the United States was highest among Hispanics (0.38 cases per million population), followed by whites (0.13 cases per million population) and then by African Americans (0.12 cases per million population).^[10]

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Prognosis

The prognosis is dependent on incubation period, the time from spore inoculation to first symptom, and the time from first symptom to first tetanic spasm. The following statements typically hold true:

• In general, shorter intervals indicate more severe tetanus and a poorer prognosis
• Patients usually survive tetanus and return to their predisease state of health
• Recovery is slow and usually occurs over 2-4 months
• Some patients remain hypotonic
• Clinical tetanus does not produce a state of immunity; therefore, patients who survive the disease require active immunization with tetanus toxoid to prevent a recurrence

A rating scale has been developed for assessing the severity of tetanus and determining the prognosis.^[16] On this scale, 1 point is given for each of the following:

• Incubation period shorter than 7 days
• Period of onset shorter than 48 hours
• Tetanus acquired from burns, surgical wounds, compound fractures, septic abortion, umbilical stump, or intramuscular injection
• Narcotic addiction
• Generalized tetanus
• Temperature higher than 104°F (40°C)
• Tachycardia exceeding 120 beats/min (150 beats/min in neonates)

The total score indicates disease severity and prognosis as follows:

• 0 or 1 – Mild tetanus; mortality below 10%
• 2 or 3 – Moderate tetanus; mortality of 10-20%
• 4 – Severe tetanus; mortality of 20-40%
• 5 or 6 – Very severe tetanus; mortality above 50%

Cephalic tetanus is always severe or very severe. Neonatal tetanus is always very severe.

The case-fatality ratio in the United States was 91% in 1947,^[10] 21-31% from 1982 to 1990, 11% from 1995 to 1997, and 18% from 1998 to 2000. Current statistics indicate that mortality in mild and moderate tetanus is approximately 6%; for severe tetanus, it may be as high as 60%. Mortality in the United States resulting from generalized tetanus is 30% overall, 52% in patients older than 60 years, and 13% in patients younger than 60 years.

Mortality is substantially higher for people older than 60 years (40%) than for those aged 20-59 years (8%). From 1998 to 2000, 75% of the deaths in the United States were in patients older than 60 years.^[10] In addition, mortality is notably higher for people who require mechanical ventilation (30%) than for those who do not (4%).

A high risk of mortality is associated with the following:

• Short incubation period
• Early onset of convulsions
• Delay in treatment
• Contaminated lesions of the head and the face
• Neonatal tetanus

Clinical tetanus is less severe among patients who have received a primary series of tetanus toxoid sometime during their life than among patients who are inadequately vaccinated or unvaccinated. Mortality in the United States is 6% for individuals who had previously received 1-2 doses of tetanus toxoid, compared with 15% for individuals who were unvaccinated.

Residual neurologic sequelae are uncommon. Mortality usually results from autonomic dysfunction (eg, extremes in blood pressure, dysrhythmias, or cardiac arrest).

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Patient Education

The importance of childhood immunizations and boosters must be stressed. Midwives and birth attendants in developing and underdeveloped countries should be given training in aseptic birthing procedures. The basics of wound care and first aid should be widely taught. Early recognition of symptoms and signs of localized tetanus and timely access to medical care are essential.

For patient education resources, see the Infections Center, Public Health Center, and Children’s Health Center, as well as Tetanus , Immunization Schedule, Adults ,and Immunization Schedule, Children.

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History

Most cases of tetanus in the United States occur in patients with a history of underimmunization, either because they were never vaccinated or because they completed a primary series but have not had a booster in the preceding 10 years. From 1995 to 1997, 54% of the reported cases in the United States had an unknown tetanus vaccination history, 22% had no known previous tetanus vaccination, 9% had 1 previous dose, 3% had 2, 3% had 3, and 9% had 4 or more. Persons who inject drugs also constitute a high-risk group.

The median incubation period is 7 days, and for most cases (73%), incubation ranges from 4 to 14 days. The incubation period is shorter than 4 days in 15% of cases and longer than 14 days in 12% of cases. Patients with clinical manifestations occurring within 1 week of an injury have more severe clinical courses.

Patients sometimes remember an injury, but often, the injury goes unnoticed. Patients may report a sore throat with dysphagia (early sign). The initial manifestation may be local tetanus, in which the rigidity affects only 1 limb or area of the body where the clostridium-containing wound is located. Patients with generalized tetanus present with trismus (ie, lockjaw) in 75% of cases. Other presenting complaints include stiffness, neck rigidity, restlessness, and reflex spasms.

Subsequently, muscle rigidity becomes the major manifestation. Muscle rigidity spreads in a descending pattern from the jaw and facial muscles over the next 24-48 hours to the extensor muscles of the limbs.

Dysphagia occurs in moderately severe tetanus as a consequence of pharyngeal muscle spasms, and onset is usually insidious over several days. Reflex spasms develop in most patients and can be triggered by minimal external stimuli such as noise, light, or touch. The spasms last seconds to minutes; become more intense; increase in frequency with disease progression; and can cause apnea, fractures, dislocations, and rhabdomyolysis. Laryngeal spasms can occur at any time and can result in asphyxia.

Other symptoms include elevated temperature, sweating, elevated blood pressure, and episodic rapid heart rate.

Sustained contraction of facial musculature produces a sneering grin expression known as risus sardonicus.

Generalized tetanus

Generalized tetanus is the most commonly found form of tetanus in the United States, accounting for 85-90% of cases. The extent of the trauma varies from trivial injury to contaminated crush injury. The incubation period is 7-21 days, largely depending on the distance of the injury site from the central nervous system (CNS).

Trismus is the presenting symptom in 75% of cases; a dentist or an oral surgeon often initially sees the patient. Other early features include irritability, restlessness, diaphoresis, and dysphagia with hydrophobia, drooling, and spasm of the back muscles. These early manifestations reflect involvement of bulbar and paraspinal muscles, possibly because these structures are innervated by the shortest axons. The condition may progress for 2 weeks despite antitoxin therapy because of the time needed for intra-axonal antitoxin transport.

Localized tetanus

Localized tetanus involves an extremity with a contaminated wound and is of highly variable severity. It is an unusual form of tetanus, and the prognosis for survival is excellent.

Cephalic tetanus

Cephalic tetanus generally follows head injury or develops with infection of the middle ear. Symptoms consist of isolated or combined dysfunction of the cranial motor nerves (most frequently CN VII). Cephalic tetanus may remain localized or may progress to generalized tetanus. It is an unusual form of tetanus with an incubation period of 1-2 days. The prognosis for survival is usually poor.

Neonatal tetanus

Neonatal tetanus (tetanus neonatorum) is generalized tetanus that results from infection of a neonate. It primarily occurs in underdeveloped countries and accounts for as many as one half of all neonatal deaths. The usual cause is the use of contaminated materials to sever or dress the umbilical cord in newborns of unimmunized mothers.

The usual incubation period after birth is 3-10 days, which explains why this form of tetanus is sometimes referred to as the disease of the seventh day. The newborn usually exhibits irritability, poor feeding, rigidity, facial grimacing, and severe spasms with touch. Mortality exceeds 70%.

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Physical Examination

Common first signs of tetanus are headache and muscular stiffness in the jaw (ie, lockjaw), followed by neck stiffness, difficulty swallowing, rigidity of abdominal muscles, spasms, and sweating. Patients often are afebrile. Stimulation of the posterior pharyngeal wall may elicit reflex spasms of the masseter muscles that cause patients to bite down as opposed to gag (spatula test).^[17]

Severe tetanus results in opisthotonos, flexion of the arms, extension of the legs, periods of apnea resulting from spasm of the intercostal muscles and diaphragm, and rigidity of the abdominal wall. Late in the disease, autonomic dysfunction develops, with hypertension and tachycardia alternating with hypotension and bradycardia; cardiac arrest may occur.

The lower extremity is the site of antecedent acute injury in 52% of patients, the upper extremity is the site of antecedent injury in 34% of patients, and the head or the trunk is the site of antecedent injury in 5% of patients.

Tetanic seizures may occur. Their presence portends a poor prognosis, and their frequency and severity are related to the severity of the disease. These seizures resemble epileptic seizures, with the presence of a sudden burst of tonic contractions. However, the patient does not lose consciousness and usually experiences severe pain. Seizures frequently occur in the muscle groups causing opisthotonos, flexion and abduction of the arms, clenching of the fists against the thorax, and extension of the lower extremities.

Patients with tetanus may present with abdominal tenderness and guarding, mimicking an acute abdomen. Exploratory laparotomies have been performed before the correct diagnosis was apparent.

Tetanospasmin has a disinhibitory effect on the autonomic nervous system (ANS). ANS dysfunction becomes progressively evident as the level of toxin in the CNS increases. ANS disturbances (eg, sweating, fluctuating blood pressure, episodic tachydysrhythmia, and increased catecholamine release) are observed. Drugs with beta-blocker effects have been used to control the cardiovascular manifestations of ANS instability, but they also have been associated with increased risk of sudden death.

Generalized tetanus

Sustained trismus may result in the characteristic sardonic smile (risus sardonicus) and persistent spasm of the back musculature may cause opisthotonos. Waves of opisthotonos are highly characteristic of the disease. With progression, the extremities become involved in episodes of painful flexion and adduction of the arms, clenched fists, and extension of the legs.

Noise or tactile stimuli may precipitate spasms and generalized convulsions. Involvement of the ANS may result in severe arrhythmias, oscillation of blood pressure, profound diaphoresis, hyperthermia, rhabdomyolysis, laryngeal spasm, and urinary retention. In most cases, the patient remains lucid.

Localized tetanus

In mild cases of localized tetanus, patients may have weakness of the involved extremity, presumably due to partial immunity; in more severe cases, they may have intense, painful spasms of the group of muscles in close proximity to the site of injury. This disorder may persist for several weeks but is usually self-limiting; however, more severe cases tend to progress to generalized tetanus.

Cephalic tetanus

Cephalic tetanus is a rare form of the disease that is usually secondary to chronic otitis media or head trauma. It is characterized by variable CN palsies, most frequently involving CN VII. Ophthalmoplegic tetanus is a variant that develops after penetrating eye injuries and results in CN III palsies and ptosis.

Rapid progression is typical. Cephalic tetanus may remain localized or, especially if left untreated, progress to generalized tetanus.

Neonatal tetanus

Neonatal tetanus presents with an inability to suck 3-10 days after birth. Presenting symptoms include irritability, excessive crying, grimaces, intense rigidity, and opisthotonos. In general, the physical examination findings are similar to those of generalized tetanus.

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Complications

Complications include spasm of the vocal cords and spasm of the respiratory muscles that cause interference with breathing.^[18] Patients experience severe pain during each spasm. During the spasm, the upper airway can be obstructed, or the diaphragm may participate in the general muscular contraction.

Sympathetic overactivity is the major cause of tetanus-related death in the intensive care unit (ICU). Sympathetic hyperactivity usually is treated with labetalol at 0.25-1 mg/min as needed for blood pressure control or with morphine at 0.5-1 mg/kg/h by continuous infusion.

Neonatal tetanus follows infection of the umbilical stump, most commonly resulting from a failed aseptic technique in a mother who is inadequately immunized. Mortality for neonatal tetanus exceeds 90%, and developmental delays are common among survivors.

Before 1954, asphyxia from tetanic spasms was the usual cause of death in patients with tetanus. However, with the advent of neuromuscular blockers, mechanical ventilation, and pharmacologic control of spasms, sudden cardiac death has become the leading cause of death. Sudden cardiac death has been attributed to excessive catecholamine productions or the direct action of tetanospasmin or tetanolysin on the myocardium.

Nosocomial infections are common when hospitalization is prolonged. Secondary infections may include sepsis from decubitus ulcers, hospital-acquired pneumonia, and catheter-related infections. Pulmonary embolism is a particular problem in drug users and elderly patients.

Further complications include the following:

• Long bone fractures
• Glenohumeral joint and temporomandibular joint dislocations
• Hypoxic injury and aspiration pneumonia
• Clotting in the blood vessels of the lung
• Adverse effects of autonomic instability,^[19] including hypertension and cardiac dysrhythmias
• Paralytic ileus, pressure sores, and urinary retention
• Malnutrition and stress ulcers
• Coma, nerve palsies, neuropathies, psychological aftereffects, and flexion contractures

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Laboratory Studies

No specific laboratory tests exist for determining the diagnosis of tetanus. The diagnosis is clinically based on the presence of trismus, dysphagia, generalized muscular rigidity, spasm, or combinations thereof. Although the laboratory findings are not diagnostically valuable, they may help exclude strychnine poisoning.

Blood counts and blood chemical findings are unremarkable. Laboratory studies may demonstrate a moderate peripheral leukocytosis.

A lumbar puncture is not necessary for diagnosis. Cerebrospinal fluid (CSF) findings are normal, except for an increased opening pressure, especially during spasms.

Serum muscle enzyme levels (eg, creatine kinase, aldolase) may be elevated.

An assay for antitoxin levels is not readily available. However, a serum antitoxin level of 0.01 IU/mL or higher is generally considered protective, making the diagnosis of tetanus less likely (though rare cases have been reported to occur despite the presence of protective antitoxin levels).

Wounds should be cultured in cases of suspected tetanus. It must be kept in mind, however, that C tetani sometimes can be cultured from the wounds of patients who do not have tetanus and frequently cannot be cultured from the wounds of patients who do.

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Spatula Test

The spatula test is a simple diagnostic bedside test that involves touching the oropharynx with a spatula or tongue blade. In normal circumstances, it elicits a gag reflex, and the patient tries to expel the spatula (ie, a negative test result). If tetanus is present, patients develop a reflex spasm of the masseters and bite the spatula (ie, a positive test result).

In 400 patients, this test had a sensitivity of 94% and a specificity of 100%.^[17] No adverse sequelae (eg, laryngeal spasm) were reported.

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Other Studies

Electromyography (EMG) may show continuous discharge of motor subunits and shortening or absence of the silent interval normally observed after an action potential.

Nonspecific changes may be evident on electrocardiography (ECG).

Imaging studies of the head and spine reveal no abnormalities.

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Approach Considerations

The goals of treatment in patients with tetanus include the following:

• Initiating supportive therapy
• Debriding the wound to eradicate spores and alter conditions for germination
• Stopping the production of toxin within the wound
• Neutralizing unbound toxin
• Controlling disease manifestations
• Managing complications

Patients should be admitted to an intensive care unit (ICU). If the facility does not have an ICU, the patient should be transferred by critical care ambulance.

Passive immunization with human tetanus immune globulin (TIG) shortens the course of tetanus and may lessen its severity. A dose of 500 U may be as effective as larger doses. Therapeutic TIG (3,000-6,000 units as 1 dose) has also been recommended for generalized tetanus.^[20] Other treatment measures include ventilatory support, high-calorie nutritional support, and pharmacologic agents that treat reflex muscle spasms, rigidity, tetanic seizures and infections.

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Initial Supportive Therapy and Wound Care

Patients should be admitted to the ICU. Because of the risk of reflex spasms, a dark and quiet environment should be maintained. Unnecessary procedures and manipulations should be avoided.

Prophylactic intubation should be seriously considered in all patients with moderate-to-severe clinical manifestations. Intubation and ventilation are required in 67% of patients. Attempting endotracheal intubation may induce severe reflex laryngospasm; preparations must be made for emergency surgical airway control. Rapid sequence intubation techniques (eg, with succinylcholine) are recommended to avoid this complication.

Tracheostomy should be performed in patients requiring intubation for more than 10 days. Tracheostomy has also been recommended after onset of the first generalized seizure.

The possibility of developing tetanus directly correlates with the characteristics of the wound. Recently acquired wounds with sharp edges that are well vascularized and not contaminated are least likely to develop tetanus. All other wounds are considered predisposed to tetanus. The most susceptible wounds are those that are grossly contaminated or that are caused by blunt trauma or bites. Wounds should be explored, carefully cleansed, and properly debrided.

In many cases, the wound responsible for tetanus is clear at presentation, in which case surgical debridement offers no significant benefit. If debridement is indicated, it should be undertaken only after the patient has been stabilized. The current recommendation is to excise at least 2 cm of normal viable-appearing tissue around the wound margins. Abscesses should be incised and drained. Because of the risk of releasing tetanospasmin into the bloodstream, any wound manipulation should be delayed until several hours after administration of antitoxin.

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Pharmacologic Therapy

Elimination of toxin production

Antimicrobials are used to decrease the number of vegetative forms of C tetani (the toxin source) in the wound. For years, penicillin G was used widely for this purpose, but it is not the current drug of choice. Metronidazole (eg, 0.5 g every 6 hours) has comparable or better antimicrobial activity, and penicillin is a known antagonist of gamma-aminobutyric acid (GABA), as is tetanus toxin. Metronidazole is also associated with lower mortality.^[21]

Other antimicrobials that have been used are clindamycin, erythromycin, tetracycline, and vancomycin. Their role is not well established.

Neutralization of unbound toxin

Tetanus immune globulin (TIG) is recommended for treatment of tetanus. It should be kept in mind that TIG can only help remove unbound tetanus toxin; it cannot affect toxin bound to nerve endings. A single intramuscular (IM) dose of 3000-5000 units is generally recommended for children and adults, with part of the dose infiltrated around the wound if it can be identified.

The World Health Organization recommends TIG 500 units by IM injection or intravenously (IV)—depending on the available preparation—as soon as possible; in addition, 0.5 mL of an age-appropriate tetanus toxoid−containing vaccine (Td, Tdap, DT, DPT, DTaP, or tetanus toxoid, depending on age or allergies), should be administered by IM injection at a separate site.

Tetanus disease does not induce immunity; patients without a history of primary tetanus toxoid vaccination should receive a second dose 1-2 months after the first dose and a third dose 6-12 months later.

Control of disease manifestations

Benzodiazepines have emerged as the mainstay of symptomatic therapy for tetanus. Diazepam is the most frequently studied and used drug; it reduces anxiety, produces sedation, and relaxes muscles. Lorazepam is an effective alternative. High dosages of either may be required (up to 600 mg/day).

To prevent spasms that last longer than 5-10 seconds, administer diazepam IV, typically 10-40 mg every 1-8 hours. Vecuronium (by continuous infusion) or pancuronium (by intermittent injection) are adequate alternatives. Midazolam 5-15 mg/hr IV has been used. If the spasms are not controlled with benzodiazepines, long-term neuromuscular blockade is required.

Phenobarbital is another anticonvulsant that may be used to prolong the effects of diazepam. Phenobarbital is also used to treat severe muscle spasms and provide sedation when neuromuscular blocking agents are used. Other agents used for spasm control include baclofen, dantrolene, short-acting barbiturates, and chlorpromazine. Propofol has been suggested for sedation.^[22]

Intrathecal (IT) baclofen, a centrally acting muscle relaxant, has been used experimentally to wean patients off the ventilator and to stop diazepam infusion. IT baclofen is 600 times more potent than oral baclofen. Repeated IT injections have been efficacious in limiting duration of artificial ventilation or preventing intubation. Case reports and small case series have suggested that IT baclofen is effective in controlling muscle rigidity,^{[23, 24]} though others have questioned this.^[25]

The effects of baclofen begin within 1-2 hours and persist for 12-48 hours. The half-life elimination of baclofen in cerebrospinal fluid (CSF) ranges from 0.9 to 5 hours. After lumbar IT administration, the cervical-to-lumbar concentration ratio is 1:4. The major adverse effect is a depressed level of consciousness and respiratory compromise.

Management of complications

Specific therapy for autonomic system complications and control of spasms should be initiated.^[26] Magnesium sulfate can be used alone or in combination with benzodiazepines for this purpose. It should be given IV in a loading dose of 5 g (or 75 mg/kg), followed by continuous infusion at a rate of 2-3 g/h until spasm control is achieved.^[7]

The patellar reflex should be monitored; areflexia (absence of the patellar reflex) occurs at the upper end of the therapeutic range (4 mmol/L). If areflexia develops, the dosage should be reduced. An infusion of magnesium sulfate does not reduce the need for mechanical ventilation in adults with severe tetanus, but it does reduce the requirement for other drugs to control muscle spasms and cardiovascular instability.^[27]

In a meta-analysis of 3 controlled trials that compared magnesium sulfate with placebo or diazepam for the treatment of patients with tetanus, magnesium sulfate did not reduce mortality or relative risk.^[28] The investigators concluded that further controlled trials were necessary to evaluate the potential effect of this therapy on autonomic dysfunction, spasms, length of ICU and hospital stay, and requirement for mechanical ventilation.

Morphine is an option. In the past, beta blockers were used, but they can cause hypotension and sudden death; only esmolol is currently recommended.

Hypotension requires fluid replacement and dopamine or norepinephrine administration. Parasympathetic overactivity is rare, but if bradycardia is sustained, a pacemaker may be needed. Clinical tetanus does not induce immunity against future attacks; therefore, all patients should be fully immunized with tetanus toxoid during the convalescent period.

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Diet and Activity

Maintenance of adequate nutrition is extremely important. Because of the risk of aspiration, patients should not be given any food by mouth. Nutrition should be provided to seriously ill patients via nasoduodenal tubes, gastrostomy tube feedings, or parenteral hyperalimentation. Consultation with a nutritionist is helpful.

The patient should be on bed rest in a room that can be kept dark and quiet. Even the slightest physical stimulus can cause a cycle of spasms.

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Consultations

An intensive care medicine specialist should be the primary physician coordinating the patient’s care. Consultations with the following specialists may be appropriate as the clinical situation dictates:

• Infectious diseases
• Toxicology - To help confirm or exclude strychnine toxicity as the cause of symptoms
• Neurology - To confirm or exclude seizures as a possible etiology of symptoms
• Pulmonary medicine – To be consulted after admission to the ICU for patients with severe respiratory symptoms or those requiring mechanical ventilation
• Anesthesiology – To be consulted after admission to the ICU if intrathecal baclofen is to be administered

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Prevention

Prevention of tetanus is accomplished through vaccination with DTP or DTaP at the ages of 2 months, 4 months, 6 months, 12-18 months, and 4-6 years. For the latest vaccination recommendations, see CDC Immunization Schedules.

For persons aged 7 years or older who have never been vaccinated against tetanus, diphtheria, or pertussis (ie, have never received any dose of DTP/DTaP/DT or Td), administer a series of 3-4 vaccinations containing tetanus and diphtheria toxoids. The preferred schedule is a single dose of Tdap, followed by a dose of Td at least 4 weeks after Tdap and another dose of Td 6-12 months later. However, Tdap can be given once as a substitute for Td in the 3-dose primary series.^[29]

Alternatively, in situations where the adult probably received vaccination against tetanus and diphtheria but cannot produce a record, vaccine providers may consider serologic testing for antibodies to tetanus and diphtheria toxin with the aim of avoiding unnecessary vaccination. If tetanus and diphtheria antitoxin levels are each higher than 0.1 IU/mL, previous vaccination with tetanus and diphtheria toxoid vaccine is presumed, and a single dose of Tdap is indicated.^[29]

Adults who received other incomplete vaccination series against tetanus and diphtheria should be vaccinated with Td to complete a 3-dose primary series of tetanus and diphtheria toxoid-containing vaccines. One dose of Tdap should be used in place of Td if the patient has never received a dose of Tdap.

Pregnancy is not a contraindication to the use of Tdap in the second and third trimester.

Secondary prevention of tetanus is accomplished after exposure through appropriate wound cleansing and debridement and the administration of tetanus toxoid (Td, Tdap, DT, DPT, or DTaP, as indicated) and TIG, when indicated. Pediatric formulations (DT and DTaP) include about the same amount of tetanus toxoid as adult Td does but contain 3-4 times as much diphtheria toxoid.

The following wounds should be considered prone to tetanus:

• Wounds that have been present for longer than 6 hours
• Deep (> 1 cm) wounds
• Grossly contaminated wounds
• Wounds that are exposed to saliva or feces, stellate, or ischemic or infected (including abscesses
• Avulsions, punctures, or crush injuries

It is not necessary to wait the typical 10 years to get the adult Tdap dose after the last Td dose. An interval as short as 2 years is suggested to reduce the likelihood of increased reactogenicity, and even shorter intervals may be appropriate if the patient is at high risk for pertussis, has close contact with infants, or may not be able to receive another vaccination. Providers should know that shorter intervals are not contraindicated, that accumulating data reinforce safety of the vaccine, and that there are no concerns about immunogenicity with the decreased interval.

Patients with tetanus-prone wounds should receive Td or DPT IM if they are younger than 7 years and if it has been more than 5 years since their last dose of tetanus toxoid. Patients who have previously received fewer than 3 doses of tetanus toxoid and patients aged 60 years or older should receive TIG 250-500 units IM, always in the opposite extremity to the toxoid.

Adults without tetanus-prone wounds should be given Td or Tdap if they have previously have received fewer than 3 doses of tetanus toxoid or if more than 10 years have passed since their last dose. Tdap is preferred to Td for adults vaccinated more than 5 years earlier who require tetanus toxoid as part of wound management and who have not previously received Tdap. Tdap is indicated only once; therefore, for adults previously vaccinated with Tdap (after age 7 years), Td should be used if a tetanus toxoid−containing vaccine is indicated for wound care.

It is important to review the immunization status of all patients who present to an emergency department for any care (regardless of chief complaint). Immunizations should be administered if a lapse of more than 10 years has occurred since the last tetanus booster. If a patient does not remember or cannot give a history of immunization, an immunochromatographic dipstick test may be appropriate and cost-effective for determining tetanus immunity in this setting, though further study is needed to determine the applicability of this approach.^[30]

The ACIP recommends vaccination at primary care visits for adolescents aged 11-12 years and for adults aged 50 years, review of vaccination histories, and updating of tetanus vaccination status. This is in addition to recommending booster doses of tetanus and diphtheria toxoid every 10 years.

In 2011 and 2012, the ACIP issued updated recommendations for the use of Tdap.^{[31, 32, 33]} Key points included the following:

• Timing of Tdap after Td – Pertussis vaccination, when indicated, should not be delayed; Tdap should be administered regardless of the interval since the last tetanus- or diphtheria toxoid−containing vaccine
• Tdap use in adults – All adults aged 19 years and older who have not yet received a dose of Tdap should receive a single dose, regardless of the interval since the last tetanus- or diphtheria toxoid−containing vaccine, then should continue to receive Td for routine booster immunization
• Wound management for adults – A tetanus toxoid–containing vaccine may be recommended as part of standard wound management in adults aged 19 years and older if it has been at least 5 years since last receipt of Td; if a tetanus booster is indicated, Tdap is preferred to Td for wound management in adults aged 19 years and older who have not received Tdap previously
• Adults aged 65 years and older – Those who have or anticipate having close contact with an infant younger than 12 months and have not received Tdap should receive a single dose of Tdap; others may be given a single dose of Tdap instead of Td if they have not previously received Tdap; Tdap can be administered regardless of the interval since the last tetanus- or diphtheria toxoid−containing vaccine; Td is then given for routine booster immunization
• When feasible, Boostrix should be used for adults aged 65 years and older; however, either of the 2 available vaccines administered to a person 65 years or older is immunogenic and would provide protection, and a dose of either may be considered valid
• Pregnant women who have not previously received Tdap – Tdap should be administered during pregnancy, preferably during the third or late second trimester (after 20 weeks’ gestation); if not given during pregnancy, it should be given immediately post partum; if a booster vaccination is indicated during pregnancy, it should be given according to the same time frame
• Pregnant women with unknown or incomplete tetanus vaccination – To ensure protection, 3 vaccinations containing tetanus and reduced diphtheria toxoids should be given, ideally at 0 weeks, 4 weeks, and 6-12 months; Tdap should replace 1 dose of Td, preferably during the third or late second trimester
• Undervaccinated children aged 7-10 years – If there is no contraindication to pertussis vaccine, a single dose of Tdap is indicated; if additional doses of tetanus and diphtheria toxoid--containing vaccines are needed, vaccinated should proceed according to catch-up guidance, with Tdap preferred as the first dose

Worldwide, neonatal tetanus may be eliminated by increasing immunizations in women of childbearing age, especially pregnant women, and by improving maternity care. Administration of tetanus toxoid twice during pregnancy (4-6 weeks apart, preferably in the last 2 trimesters) and again at least 4 weeks before delivery is recommended for previously unimmunized gravid women. Maternal antitetanus antibodies are passed to the fetus, and this passive immunity is effective for many months.

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Medication Summary

The goals of pharmacotherapy are to stop toxin production within the wound, to neutralize unbound toxin, and to control disease manifestations. Drugs used to treat muscle spasm, rigidity, and tetanic seizures include sedative-hypnotic agents, general anesthetics, centrally acting muscle relaxants, and neuromuscular blocking agents. Antibiotics are used to prevent multiplication of Clostridium tetani, thus halting production and release of toxins. Antitoxins are given to neutralize unbound toxin.

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Metronidazole (Flagyl)

• Dosing, Interactions, etc.

Clinical Context:  Metronidazole is active against various anaerobic bacteria and protozoa. It appears to be absorbed into cells, and intermediate-metabolized compounds that are formed bind DNA and inhibit protein synthesis, causing cell death. A 10- to 14-day course of treatment is recommended. Some consider it the drug of choice in tetanus because of its safety profile, efficient penetration into wounds and abscesses, and negligible central nervous system (CNS) excitation.

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Penicillin G (Pfizerpen)

• Dosing, Interactions, etc.

Clinical Context:  Penicillin G is a bactericidal antibiotic that binds to and inhibits penicillin-binding proteins, which are transpeptidases that cross-link peptidoglycans, the final step in bacterial cell wall synthesis. Inhibition of cell wall synthesis and autolytic enzyme activation are responsible for its bactericidal action on dividing bacteria.

A 10- to 14-day course of treatment is recommended. Large intravenous (IV) doses of penicillin may cause hemolytic anemia and neurotoxicity. Cardiac arrest has been reported in patients receiving massive doses of penicillin G potassium. Patients with renal failure are particularly at risk.

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Doxycycline (Vibramycin, Doryx, Doxy 100, Adoxa, Monodox)

• Dosing, Interactions, etc.

Clinical Context:  Doxycycline inhibits protein synthesis and thus bacterial growth by binding to 30S and possibly 50S ribosomal subunits of susceptible bacteria. A 10- to 14-day course of treatment is recommended.

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Erythromycin (E.E.S., EryPed, Erythrocin, Ery-Tab)

• Dosing, Interactions, etc.

Clinical Context:  Erythromycin is a bacteriostatic agent that inhibits protein synthesis by binding to the 50S subunit of bacterial ribosomes. It is not the drug of choice for tetanus but may be used when the drugs of choice cannot be administered for some reason.

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Clindamycin (Cleocin)

• Dosing, Interactions, etc.

Clinical Context:  Clindamycin is a bacteriostatic agent that binds to the 50S ribosomal subunit. It is not the drug of choice for tetanus and may be used only if the drugs of choice cannot be used.

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Tetracycline

• Dosing, Interactions, etc.

Clinical Context:  Tetracycline is a bacteriostatic agent that inhibits protein synthesis. It is not the drug of choice for tetanus and may be used only if the drugs of choice cannot be used.

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Vancomycin

• Dosing, Interactions, etc.

Clinical Context:  Vancomycin is a bactericidal agent that inhibits cell wall and RNA synthesis. It is not the drug of choice for tetanus and may be used only if the drugs of choice cannot be used.

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Class Summary

These agents are used to eradicate clostridial organisms in the wound, which may produce tetanus toxin. They are administered to patients with clinical tetanus; however, their efficacy is questioned. Penicillin G was long considered the drug of choice, but metronidazole is now considered the antibiotic of choice.

Although tetracyclines are an alternative in patients who have a history of serious allergic reactions to penicillin or metronidazole (eg, urticaria, anaphylaxis), strong consideration should be given to desensitizing the patient to penicillin before resorting to alternative agents. Large doses of antibiotic are recommended to favor diffusion into the devitalized tissue.

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Diazepam (Valium, Diastat, Diazepam Intensol)

• Dosing, Interactions, etc.

Clinical Context:  Diazepam modulates the postsynaptic effects of GABA-A transmission, thereby increasing presynaptic inhibition. It appears to act on part of the limbic system, the thalamus, and hypothalamus to induce a calming effect. It is also an effective adjunct for the relief of skeletal muscle spasm caused by upper motor neuron disorders. Diazepam rapidly distributes to other body fat stores. To avoid adverse effects, individualize dosage and increase it cautiously.

Rapidly distributes to other body fat stores. Twenty minutes after initial IV infusion, serum concentration drops to 20% of Cmax.

Individualize dosage and increase cautiously to avoid adverse effects.

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Midazolam (Versed)

• Dosing, Interactions, etc.

Clinical Context:  Midazolam is a shorter-acting benzodiazepine sedative-hypnotic that is useful in patients requiring acute or short-term sedation. It also has amnestic and antiepileptic effects.

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Lorazepam (Ativan)

• Dosing, Interactions, etc.

Clinical Context:  Lorazepam is a sedative hypnotic with a short onset of effects and a relatively long half-life. By increasing the action of gamma-aminobutyric acid (GABA), a major inhibitory neurotransmitter in the brain, lorazepam may depress all levels of the central nervous system, including the limbic and reticular formation. The drug is an excellent choice when the patient needs to be sedated for longer than 24 hours.

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Phenobarbital

• Dosing, Interactions, etc.

Clinical Context:  The drug dosage must be small enough to ensure that respirations are not depressed. If the patient is already on a ventilator, higher dosages may provide the desired sedation.

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Class Summary

Sedative-hypnotic agents are the mainstays of tetanus treatment. Benzodiazepines are the most effective primary agents for muscle spasm prevention and work by enhancing gamma-aminobutyric acid (GABA) inhibition. Diazepam is the most frequently studied and used drug. Lorazepam is an effective alternative. Phenobarbital is another anticonvulsant that may be used to prolong the effects of diazepam. Other agents used for spasm control include baclofen, dantrolene, short-acting barbiturates, and chlorpromazine.

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Baclofen (Lioresal, Gablofen)

• Dosing, Interactions, etc.

Clinical Context:  Baclofen, a central muscle relaxant, is a presynaptic GABA-B receptor agonist that may induce hyperpolarization of afferent terminals and inhibit both monosynaptic and polysynaptic reflexes at spinal level. It lessens flexor spasticity and hyperactive stretch reflexes of upper motor neuron origin.

Baclofen is well absorbed, with an average oral bioavailability of 60% and a mean elimination half-life of 12 hours. Steady state is reached within 5 days with multiple dose administration. Metabolism occurs in the liver (through P450-dependent glucuronidation and hydroxylation); 6 major and a few minor metabolites are produced. Elimination is through renal excretion.

For intrathecal (IT) administration, a pump is implanted subcutaneously (SC), and a catheter is implanted in the subarachnoid space of the spinal canal (where the medication is administered). Less medication is needed, and systemic effects are decreased. This agent is reported to be effective in about 20% of patients; it appears to be of dramatic benefit in as many as 30% of children with dystonia, though the benefit not always sustained.

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Dantrolene (Dantrium, Revonto)

• Dosing, Interactions, etc.

Clinical Context:  Dantrolene stimulates muscle relaxation by modulating skeletal muscle contractions at a site beyond the myoneural junction and by acting directly on the muscle. It may reduce painful cramping and detrimental muscle tightening. It is not approved by the US Food and Drug Administration (FDA) for use in tetanus but has been described in a small number of case reports.

Dantrolene acts peripherally at muscle fiber rather than at the neural level; it reduces muscle action potential–induced release of calcium and also affects intrafusal and extrafusal fibers and spindle sensitivity. It has no action on smooth or cardiac muscle tissue. Dantrolene induces release of calcium ions into the sarcoplasmic reticulum, subsequently decreasing the force of excitation coupling.

Dantrolene is preferred for the cerebral form of spasticity; it is less likely to cause lethargy or cognitive changes, as baclofen and diazepam do. It can be administered either orally or IV. The IV form is much more expensive and should be reserved for patients unable to take oral medications. Most patients respond to dosages of 400 mg/day or less. The drug is eliminated in urine and bile.

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Class Summary

Skeletal muscle relaxants can inhibit both monosynaptic and polysynaptic reflexes at spinal level, possibly by hyperpolarization of afferent terminals. Benzodiazepines are used to control muscle spasms and to provide sedation. Dantrolene and baclofen may also be considered for severe spasticity and may assist with shortening duration of artificial ventilation. The use of propofol has been proposed.

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Propofol (Diprivan)

• Dosing, Interactions, etc.

Clinical Context:  Propofol is a phenolic compound that elicits a sedative-hypnotic effect. It is used for induction and maintenance of anesthesia or sedation. It has also been shown to have anticonvulsant properties.

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Class Summary

These agents stabilize the neuronal membrane so the neuron is less permeable to ions. This prevents the initiation and transmission of nerve impulses, thereby producing the local anesthetic effects.

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Tetanus immune globulin (Hypertet S/D)

• Dosing, Interactions, etc.

Clinical Context:  TIG is used to prevent tetanus and to treat patients with circulating tetanus toxin. It provides passive immunity. TIG should be used to treat all patients with active tetanus, in combination with other supportive and therapeutic treatments. Should also be used to prevent tetanus in patients with inadequate or unknown immunization status after an acute injury. Administration should begin as soon as the clinical diagnosis of tetanus is made.

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Class Summary

Antitoxins are used to neutralize any toxin that has not reached the CNS. They are used for passive immunization of any person with a wound that might be contaminated with tetanus spores.

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Vecuronium

• Dosing, Interactions, etc.

Clinical Context:  Vecuronium is a prototypical nondepolarizing neuromuscular blocking agent that reliably results in muscular paralysis. For maintenance of paralysis, a continuous infusion may be used. Infants are more sensitive to neuromuscular blockade activity, and though the same dose is used, recovery is prolonged by 50%. This drug is not recommended for use in neonates.

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Class Summary

Neuromuscular blocking agents inhibit the transmission of nerve impulses at neuromuscular junctions of skeletal muscles or autonomic ganglia.

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Diphtheria & tetanus toxoids/acellular pertussis vaccine (Daptacel, Infanrix)

• Dosing, Interactions, etc.

Clinical Context:  DTaP may be administered into the deltoid or midlateral thigh muscles in children and adults. In infants, the preferred site of administration is the midlateral thigh muscles.

This vaccine promotes active immunity to diphtheria, tetanus, and pertussis by inducing the production of specific neutralizing antibodies and antitoxins.

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Tetanus & reduced diphtheria toxoids/acellular pertussis vaccine (Adacel, Boostrix, Tdap)

• Dosing, Interactions, etc.

Clinical Context:  Promotes active immunity to diphtheria, tetanus, and pertussis by inducing the production of specific neutralizing antibodies and antitoxins. It is indicated for active booster immunization for persons aged 10 or older (Adacel approved for ages 10-64 y, Boostrix approved for ages 10 y or older). It is the preferred vaccine for adolescents scheduled for a booster vaccination.

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Class Summary

Active immunization increases resistance to infection. Vaccines consist of microorganisms or cellular components that act as antigens. Administration of the vaccine stimulates the production of antibodies with specific protective properties. Administer tetanus toxoid vaccine for wound prophylaxis if the vaccine history is unknown or if fewer than 3 tetanus toxoid immunizations have been administered.

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