Tetanus lecture

2021-01-31 12:00 AM

The wound has a lack of oxygen and is sealed, the organization is much necrotic, anaemia, foreign bodies in the wound, other pus-causing bacteria attached

Define

Tetanus is an acute infectious disease caused by the bacillus Clostridium tetani and its neurotoxin exotoxin. The disease spreads through damaged skin and mucous membranes. The clinical feature is a state of persistent muscle spasm and spastic episodes. It starts with spastic chewing muscles, then spreads to the muscles of the face, torso, and extremities.

Research history

Tetanus has long been known as the clinical picture. In 1884 Nicolaier found the tetanus bacillus causing disease. In 1889 Kitasato cultured tetanus bacillus in an anaerobic field. In 1890 Faber found the exotoxins of the tetanus bacillus and its pathogenic role. Then, Von Behring and Kitasato used anti-tetanus serum to treat tetanus. In 1925 Ramon criticized the creation of tetanus toxin as a preventive vaccine.

Epidemiology

Pathogens

Clostridium bacillus. tetani (also known as Nicolaier bacillus), is an anaerobic bacillus, gram (+), producing spores. The spores are found in soil, human, and animal feces. The spores are very resistant to heat and antiseptics. Poor resistance nutrition. Cl. tetani produces exotoxins and causes disease due to this toxin (Tetanospamine).

Route of transmission

Mainly soil, human and animal feces contain tetanus spores.

Wounds of patients with tetanus.

Infection

Through wounds of the skin and mucous membranes infected with tetanus spores.

The wound can be small and discreet, such as needle stains, picking ears, flossing teeth, stabbing spikes ... to large, wide, many niches encountered in labor and combat. Sometimes it can even be seen after surgery, curettage, cutting the umbilical cord, etc. with instruments contaminated with tetanus spores.

The wounds with lack of oxygen and is sealed, the organization is much necrotic, anemia, foreign bodies in the wound, there are other pus-causing bacteria attached ... to facilitate dentistry the development of tetanus cells causes disease.

Sensitivity, immunity, and fluid properties

Tetanus arose must meet 3 conditions:

Not getting the tetanus vaccine, or being given incorrectly, so there's no immunity.

There are wounds in the skin and mucous membranes infected with tetanus spores.

There is a severe lack of oxygen in the wound due to: The wound is sealed, the organization is much necrotic, anemia, foreign bodies in the wound, other pus-causing bacteria ...

Tetanus doesn't have natural immunity, so everyone who hasn't been vaccinated can get sick.

After the disease does not give immunity. But after a detox injection (Anatoxine) will give relatively stable immunity.

Translation properties:

Only scattered, no major epidemic occurred. It is rare to have a small epidemic occurring in a battle or in a hospital due to the same source of infection (from the soil, surgical equipment ...).

The disease is common in poor countries with poor vaccination and sanitation conditions.

Mechanism of pathogenesis

The disease is not caused by the pathogen itself but by its neurotoxin (Tetanospasmin).

The tetanus toxin from the wound travels to the peripherals of motor neuron terminals and then enters the axon and travels to the nerve cell stem in the brain and spinal cord by reverse movement in nerves. At the same time, the toxin also travels across the snap to presynaptic terminals of neurons that inhibit and inhibit the release of chemical mediators such as Glycine, Gamma Amino Butyric Acid (GABA). Use to inhibit the activity of alpha motor neurons in the anterior spinal horn. While the motor neuron stimulation, alpha persists and increases. As a result, the action of the alpha motor neuron is uncontrolled and causes spasticity of the striated muscles. Whenever there is a stimulus (internal or external) stiff convulsion will occur.

Likewise, due to the loss of inhibition, the progenitor parasympathetic neurons in the lateral gray matter of the spinal cord increase, causing the concentration of Catecholamine in the blood to increase. Consequently, producing sympathetic enhancement symptoms such as increased fever, sweating, rapid pulse, increased blood pressure, decreased stomach and intestinal contractility, peripheral blood vessel constriction.

Tetanus toxins, like bacilli toxins, can block the release of neurotransmitters in the synapses of muscles and cause muscle weakness or paralysis.

In local tetanus: Only certain nerves that govern some muscles are damaged by the toxin.

In systemic tetanus: Due to the tetanus toxin from the wound spills into the bloodstream, the lymphatic vessels spread to all nerve ends. The blood-brain barrier prevents the toxin from directly entering the central nervous system. Tetanus toxin can only migrate to the central nervous system via the nervous path. It is thought that the intracellular retrograde travel time of the toxin is equivalent for all nerves when the short cord is affected anteriorly and the long cord is posterior. This explains the symptoms of muscle spasms that appear one after another: first the stiffness of the jaw, then the muscles of the head, face, neck, and muscles in the torso, and finally the limbs.

Clinical

Divide the clinical form

According to progress

Tetanus is extremely acute.

Acute tetanus.

Subacute and chronic tetanus.

According to zoning

Systemic tetanus.

Local tetanus (tetanus chi, early tetanus, etc.)

According to the circumstances of tetanus

Tetanus after abortion.

Tetanus after injection /

Umbilical tetanus.

Tetanus after burns.

Tetanus after surgery.

Tetanus unknown entrance and so on

Symptom clinical form

Tetanus acute, systemic, severe

Common and typical disease form.

Incubation period:

From 5 to 20 days, on average 7 days. May have warning signs: Pain in the wound, twitching of the muscles around the wound.

Onset period:

The main symptom and onset are jaw stiffness (the first and always present symptom). At first, it is only difficult to open the mouth, then the stiffness of the jaw becomes stronger, continuously and unable to open.

Other symptoms: Anxiety, marked insomnia. Systemic pain, mild myalgia, increased tendon reflexes, may have difficulty swallowing, facial muscle contraction, stiff neck, tachycardia.

There is a wound (entrance).

The onset period lasts 1-3 days. These can be very heavy in just a few hours.

Full-play period:

Counted from the onset of generalized stiffness.

Jaw stiffness becomes typically palpable and visible, causes difficulty speaking, difficulty swallowing with food or drink, pronounced jaw tightening.

Body spasticity:

Muscle contraction in the face: Make a grimace, "suffering" (risus sardonicus).

Muscle contraction in the neck (highlighting the brisket sternum), the nape muscle (making the neck arch and stiffen the nape of the neck.

Muscle spasms in the back that cause back arching (opisthotonos) are sometimes experienced back bending or sideways bend.

Muscle contraction in the chest, abdomen, diaphragm makes prominent muscles move with poor breathing, shallow breathing, and palpation of the abdomen as hard as wood.

Spasticity of the limbs: The arms are usually folded, legs straightened, and stiff.

Spasms of the throat and larynx cause difficulty swallowing, difficulty breathing, difficulty speaking, sore throat.

Muscle contraction in the episiotomy causes urinary retention, constipation.

Systemic stiffening (convulsions) convulsions:

On the background of generalized muscle spasms, paroxysmal spastic seizures appeared continuously. A seizure usually occurs when stimuli such as: sound, light, search, injection, phlegm suction ... or may be spontaneous.

Nature of seizures: Initially only in a few muscle groups, then spread to all muscle groups. Time 1 attack from a few seconds to a few minutes.

The number of attacks: Within 24 hours from a few to hundreds of attacks, sometimes consecutive.

The seizure was very strong, causing pain to the patient, causing the patient to worry and fear, while the patient remained awake. During a seizure, the patient may turn cyanosis due to respiratory failure, sweating, bending up or to the side, which can cause complications such as muscle rupture and tear, broken bones, throat spasms, stiffness of the diaphragm and larynx, causing asphyxiation and sudden death.

Other symptoms:

Due to plant neurological disorders:

Fever gradually increases to 39 - 40 0 C or more.

Tense and rapid pulse, sometimes arrhythmia.

Blood pressure increases in bouts, or constantly, sometimes also has a slow heart rate, blood pressure drops and can stop the heart suddenly.

Increased secretion of phlegm, sweating.

There is dehydration, electrolytes due to high fever, sweating, increased production of phlegm, poor appetite.

Acidosis: Lack of oxygen leads to anaerobic metabolism, causing acidosis.

Fast breathing, if severe respiratory failure may disturb the cyanosis.

Complications:

Cardiovascular: thromboembolism, embolism, heart failure, cardiac arrest, cardiovascular collapse ...

Respiratory: Bronchitis, lung infection, respiratory failure, apnea, atelectasis, pulmonary embolism.

Sepsis: Usually caused by gram (-) bacteria or cause embolism, urinary tract infection, ulcer due to long stay.

Kidney failure

Gastrointestinal: Gastrointestinal bleeding, intestinal obstruction.

Musculoskeletal: Broken skeletal muscles, tendons, fractured bones, wrong joints, atelectasis.

Neurology: Cranial nerve paralysis, psychosis.

The prognosis of systemic tetanus is divided into 3 levels:

Medium, heavy, very heavy.

Severe acute systemic tetanus has the following criteria:

Not been vaccinated before.

When the injury was not given preventive treatment (injected with anti-tetanus serum).

Age over 50 years old and children under 5 years old.

Location: Obesity, alcoholism, chronic respiratory, cardiovascular, liver, kidney diseases, pregnant women ...

Wounds: located near the central nervous system, crushed many nooks and crannies, purulent inflammation, foreign bodies, fractures, burns, post-surgery, intramuscular injection, post-abortion, umbilical tetanus, etc.

Be taken to the hospital late.

Clinical manifestations: Diseases from 6 to 14 days; spread time (from the hard of the jaw to the seizure attack) is from 24-48 hours, the jaw tightness is 1-2cm, there are long, fast (> 10 attacks/day), difficulty swallowing sputum congestion drooling, difficulty breathing clearly, fever 39-400C, pulse 120-140 times/minute, high blood pressure, heavy sweating, acidosis.

Mortality rate:

Tetanus is a serious disease with a high mortality rate, especially in neonatal tetanus, tetanus in the elderly, obstetrical tetanus, tetanus with a short incubation period and onset. Mortality depends on the country. In advanced countries, this rate is <10%, in poor countries, the death rate is about 30% - 40% depending on the author. In our country, the death rate has decreased significantly.

Symptoms of other clinical forms

Tetanus is very acute: very short incubation, death within 24 - 48 hours due to sudden cardiac arrest, and laryngospasm.

Acute form.

Subacute and chronic form: Symptom is longer than 3 weeks, the spread of muscle spasticity is slow, rarely systemic spasticity, often prominent signs of jaw stiffness, stiff neck, facial muscle contraction. Seizures are minimal and only stimulated. Seizures are usually mild, discreet, and very distant between attacks, with very few general signs. Progression usually resolves but takes a long time, but sudden death, especially acute respiratory failure, occurs during and after a seizure.

Local tetanus: There are 2 following:

Tetanus limbs: Usually in patients who have been injected with SAT with a long incubation period, usually on the lower extremities (very rare in the upper limb), convulsions at the wound. Increased muscle tone, cramps, patella, fibrillation of the feet or patella the prognosis is usually good but can turn into secondary systemic tetanus with the sign of jaw stiffness.

Head tetanus: Usually after head injuries, there is spastic jaws, stiff neck, facial muscle spasms. Depending on the disease without or with difficulty swallowing (causing tetanus form of hydrophobia), paralysis of one or more of the cranial nerves (peripheral type VII wire III, IV, VI, etc.), mental disorders.

Tetanus after abortion: The disease is often severe, fatal, high, and fast.

Umbilical tetanus: Very heavy.

Postoperative tetanus: Rare but often severe, common after bowel surgeries, tooth extraction, tonsils cutting, etc. with tools that are not sterilized well.

Tetanus after injection: Quinine especially after injection is usually very severe.

Tetanus after burns: Also, very severe.

Tetanus with unknown entry: Often has a better prognosis, pay attention to find the entrance is a tear in the mouth and gastrointestinal tract, possibly a very small scarred wound that the patient has ignored or forgot to go.

Definitive diagnosis

 Mainly based on clinical:

There is a doubtful wound is the entrance.

The first symptom is jaw stiffness, then muscle spasms in the following order: head, face, torso and extremities. The muscles are constantly contracting.

Paroxysmal spastic seizures against the background of spastic muscles.

Haven't been vaccinated against tetanus.

Differential diagnosis

When there are only signs of stiffness (at the onset)

It is necessary to make differential diagnoses with regional infections such as Amydal inflammation, inflammation of the mouth base, inflammation around the teeth, eruption of wisdom teeth, temporomandibular arthritis ... These diseases have characteristics: Often marked pain on one side, with swelling of nearby lymph nodes. Not accompanied by spasticity of facial muscles, neck muscles. Jaw stiff but can still try to open, does not cause stiffening. Test: Leukocytes in the blood increase.

When there has been a seizure, it must be distinguished from

Meningitis: Unlike tetanus, it has stiff neck and back muscles, but not jaw stiffness. Cerebrospinal fluid changes according to pathology.

Strychnine poisoning: Muscle spasticity all over the body at the same time without going through jaw stiffening phase, without fever, with a history of using Strychnin.

Tetani attack (due to hypocalcemia): Common in children and pregnant women, often spasms and convulsions in the extremities, less back spasticity, no jaw stiffness, Chvostek and Trousseau signs positive count.

Hysteria: Seizures occurred suddenly, muscle tone after the attack returned to normal, no fever, no wound.

Rabies: With hydrophobic tetanus, it must be distinguished from rabies. In rabies, only temporary muscle spasticity, also tetanus, and persistent muscle spasticity. Rabies has a history of dog bites.

Treatment

The principles of treatment

There are 6 principles

Anti-spasticity and stiffness.

Treatment of the entrance wound of bacteria and antibiotics to kill tetanus bacillus.

Neutralizes tetanus toxins.

Ensuring ventilation, preventing respiratory failure.

Treatment of other symptoms: balance of electrolyte water, energy, anti-acidosis, cardiovascular support, anti-vegetative neurological disorders, etc.

Regular care, nursing, good nutrition ...

Specific treatment

Anti-convulsions and muscle spasms

Is the most important measure. There are many drugs that can be used.

The most ideal treatment goal is: controlling seizures without hypoventilation, drug overdose leading to coma.

The dose of anticonvulsants is not a common dose for all patients, but must be based on the severity of the disease, the sensitivity to the drug of each patient, and adjusted hourly according to the progress of the disease.

Treatment tactics:

Base medicine: Spread evenly over 24 hours, the most preferred is Diazepam (Valium, Valium) orally (via gastric aspiration) or intravenous route. Each time from 10mg - 20mg, every 1 to 4 hours use 1 time. 24-hour dose from 1- 5mg / kg; up to 8-10mg / kg / 24h. Single-dose, the interval between drug administration, the 24-hour dose depends on the degree of seizure, spasticity, and drug sensitivity of each patient. Therefore, in order to rationalize the drug, it is necessary to monitor the number of seizures and the nature of the seizure in 24 hours.

Combination drug: Used alternately when many strong, prolonged, continuous seizures as directed by a doctor. Often used a mixture of nerve paralysis (cocktail lytic), according to the formula:

Aminazin: 25 - 50 mg.

Thiantan: 25 - 50 mg (or replace Demerol 1% -1ml).

Scopolamine: 0.05% x 0.5 ml - 1ml. (or replace with 10 mg Valium x 1 ampoule).

Sodium chloride 90/00: just 10ml.

Each injection from 2-4ml to stop the attack.

Some other drugs can be used in the treatment of anticonvulsants in tetanus, but caution should be exercised such as Gardena, dolargan, cloral hydral, pentothal ...

Treatment of the entrance wound and antibacterial drugs:

Purpose: Kills tetanus bacillus and purulent bacteria in coordination, eliminates the source of tetanus toxin, and eliminates one of the important sources of stimulation causing convulsions ...

Specifically:

Open the wound mouth, filter the necrotic organization, destroy niches, take foreign objects. Do not stitch the wound tightly (before handling the wound, use a serum against tetanus toxin and anticonvulsant).

Continuously drip 1/4000 purple medicine solution or hydrogen peroxide on the wound.

Antibiotics: Often use penicillin from 2 million to 4 million UI / day for adults, about 7 days to 10 days.

Other antibiotics that can be used instead are Ampicillin, when allergic to penicillin, use erythromycin, metronidazole ...

If the wound in the limb is fractured, crushed, or necrotic and difficult to preserve, but the seizure threatens the patient's life, amputation should be indicated.

Neutralization of tetanus toxins:

Purpose: Neutralizes toxins circulating in the blood and toxins from the wound that continue to enter the blood (has no effect on toxins that have attached to the nervous organization).

How to use:

Anti-tetanic serum (SAT: serum anti tetanic). The SAT is extracted from horse serum that has been immunized against tetanus. SAT dose is 10,000-15,000 UI (works as higher doses), injecting 3,000 to 5,000 UI around the wound. The remainder were injected intramuscularly, in other locations (using only 1 dose). SAT has the advantage of being inexpensive but can cause allergies and serum sickness (with multiple injections). Therefore, the reaction must be tested before the injection and when necessary, the Besredka hypersensitivity method should be administered.

Or use human anti-tetanus immune globulin (TIG: tetanus immune globulin) with a dose of 500 units, intramuscularly, for a single-use. Works like higher dosages. TIG is safe to use, no reaction, but very expensive.

Tetanus detoxification (AT: Anatoxin) for active immunity, injected in a limb far away from where the anti-tetanus serum was injected.

Ensuring ventilation, preventing respiratory failure:

Aspiration of phlegm, intermittent oxygen breathing, reduction of abdominal distension (stomach inhalation, anal inhalation), constipation and urinary retention. Anti-convulsions, muscle spasms. Antibiotics against multiple respiratory infections.

Is indicated for tracheostomy when:            

Wheezing and a lot of sputum clogging.    

Difficulty swallowing, choking.

The seizure was strong, continuous, long, and cyanosis after the seizure.      

The chest is not moving, breathing is shallow, purple in color

There are laryngospasm:

Give artificial ventilation (either mechanical or hand squeeze) through the tracheal opening when:

There are manifestations of respiratory damage such as apnea, even when the attack is moderate or the state of prolonged breathing failure.

The seizure was rapid, rapid, and had a poor response to anticonvulsants. In this case, using a ventilator and muscle relaxants (Curare).

Treat some other symptoms:

Ensuring energy: From 3,000 - 4,000 calories/day (by eating sugar through inhalation and intravenous infusion), increase protein infusion.

Electrolyte Water Balance: Based on central venous pressure and electrolytes to adjust. A minimum amount of water given is 2-3 liters / 24 hours by glucose solutions of 5%, 10%, 30%, ringer lactate ...

Anti-acidosis: Using 1.4% sodium bicarbonate solution, used from 300 - 500 ml / day.

Cardiovascular aids: Uabain, spactein.

Vitamins B1, B6, and C.

Anti-vegetative neurological disorders: When the circuit is too fast use:

Propranolol tablets: 40 mg x 1-2v / 24 hours, divided into 2-4 doses (each from 1/2 to 1 tablet). Use about 5-7 days. Note: When using it should be careful to monitor the circuit, when the circuit returns <90 times/min, then stop.

Heparin can be used to prevent and prevent intravascular clotting disorders, especially pulmonary capillaries.

Caring aide:

Gastrointestinal aspiration (preferably after opening the trachea and taking an anticonvulsant to prevent laryngospasm), bladder aspiration when urinary retention.

Keep in a quiet, private room, avoid stimuli such as noise, light, limit search, injection ...

Anti-ulcer: Lying on a bed, applying talcum powder, turning and cleaning the body, etc.

Monitor conditions: pulse, blood pressure, temperature, breathing, jerking attack, sweating, urine ...

Preventive

Vaccine AT (anatoxin)

Tetanus vaccine is made from tetanus toxin that has lost its toxicity (detoxification).

Tetanus vaccine from Pasteur Institute (France) each dose contains 40 UI in 0.5ml. Dose 1 and dose 2 were injected about 4-6 weeks apart. The third dose is injected 6-12 months after the second dose (intramuscularly or subcutaneously), then every 10 years, 1 dose is repeated.

For young children, tetanus vaccine is often combined with pertussis, diphtheria, etc. vaccines for vaccination.

Prevention after injury

Cut, wash, disinfect the wound.

Human immunoglobulin injection: a dose of 250 UI (2 ml) to 500 UI (4 ml), protection of 30 days intramuscularly.

If this is not available, use SAT (Serum Anti-Tetanic): Dose from 1,500UI to 3,000 UI, intramuscularly.