Stenosing laryngotracheitis (croup syndrome)

Stenosing laryngotracheitis is one of the most common emergency conditions in young children (from 3 months to 3 years), accompanied by croup syndrome. Croup, croup syndrome in children (staroshlotl. Croupe - croak) can develop at any age, but more often in the first 2 years of life.

[1], [2], [3]

What causes stenosing laryngotracheitis?

Stenosing laryngotracheitis, or croup in recent years, SARS are dominant: influenza, parainfluenza, respiratory syncytial (MS), adenovirus infection, etc. Diphtheria of the oropharynx as the cause of croup is very rare today. Perhaps the development of croup with herpes infection (aphthous stomatitis), measles, chicken pox. Due to the small diameter of the upper respiratory tract in young children, even a slight swelling of the mucous membrane leads to a pronounced narrowing of their lumen with an increase in resistance to air flow.

Causative agents of the disease: 

• influenza A virus;
• parainfluenza virus types I and II;
• PC infection;
• adenovirus infection;
• diphtheria
• other bacterial infections;
• chemical burn in case of poisoning.

Stenosing laryngotracheitis is caused by inflammatory edema, which develops below the glottis, in the sub-storage space. Of additional importance are exudate, accumulating in the lumen of the respiratory tract, and laryngeal muscle spasm, aggravated by hypoxia.

Other causes of croup

Acute bacterial tracheitis (OBT) is also called acute purulent stenosis, occlusive laryngotracheobronchitis, secondary or late croup. In its etiology, Staphylococcus aureus is of primary importance, to a lesser extent - Pfeiffer sticks, pneumococcus. OBT occurs as a result of the layering of purulent infection on acute viral damage to the mucous membrane of the larynx and trachea. In the domestic literature is described as secondary croup with acute respiratory viral infections, influenza, measles, etc.

Occurs MBT more often in children older than 3 years. It is characterized by high body temperature, a long-lasting and often taking on the character of remitting or hectic, a gradual increase in the symptoms of croup and their slow reverse development; leukocytosis and neutrophilia are detected in blood, staphylococcus is sown from sputum.

Treatment consists of oxygen supply, inhalations of mucolytics (trypsin, himopsin, DNA-aza, etc.), antibiotics are administered intravenously in high doses (“protected” penicillins, cephalosporins of the 2nd-3rd generation), often in combinations, antistaphylococcal hyperimmune preparations are administered, implement IT in order to maintain water balance and detoxification. Purulent complications often develop: pneumonia, pleurisy, abscess, sepsis, etc.

The croup syndrome or its clinical imitation is also observed in a number of diseases, for the timely detection of which it is necessary to promptly carry out differential diagnostics followed by specific therapy.

Larynx diphtheria is a classic example of inflammatory laryngitis, laryngeal stenosis, the basis of which mechanism is mucosal edema, muscle spasm of the larynx and the presence of fibrinous films that significantly reduce the lumen of the respiratory tract. Localized or widespread laryngeal diphtheria is currently observed in adult patients or unvaccinated young children. Stenosis of the larynx gradually and steadily progresses to the stage of asphyxia. The main treatment for diphtheria croup is the introduction of antitoxic anti-diphtheria serum in a total dose of 30-60 thousand units. Regardless of age within 1-2 days.

Zagothy abscess often develops in infants and young children on the background of acute respiratory viral infections due to the accession of a bacterial infection caused by a hemophilic rod. The resulting bulging of the posterior pharyngeal wall is an obstacle to the passage of a stream of air and often mimics the clinical manifestations of laryngeal stenosis or EG. On examination, the throat can reveal hyperemia of the mucous membrane, its bulging in the throat. Radiographically, an increase in the retro-pharyngeal or retro-tracheal space is observed in the lateral projection of the neck.

At the beginning of the disease, large doses of penicillin are effective, as well as semi-synthetic penicillins, cephalosporins. If necessary, conduct surgical intervention.

[4], [5], [6], [7]

Symptoms of stenosing laryngotracheitis

Stenosing laryngotracheitis occurs mainly in children aged 1-6 years on the 1-2 day of respiratory infection. It develops as a result of laryngeal edema below the glottis, which is expressed in the inspiratory stridor. Edema of the vocal cords is manifested by dysphonia (hoarseness of voice).

As a result of reducing the diameter of the airways, resistance to air flow increases and respiration increases: tachypnea, the inclusion of additional muscle groups in the work of breathing. With the progression of obstruction, a violation of gas exchange with the subsequent development of hypoxemia, cyanosis and carbon dioxide accumulation is possible. These are late signs of croup - precursors of complete airway obstruction and respiratory arrest.

Symptoms of stenosing laryngotracheitis often develops at night. Characteristic is the appearance of inspiratory dyspnea — an extended, noisy inhalation, dysphonia (hoarse voice and a rough, “barking” cough) or aphonia (loss of voice and the appearance of a silent cough). With an increase in obstruction of the upper respiratory tract, dyspnea and the involvement of auxiliary muscles in the act of breathing increase, there is a decline in the pliable places of the chest during inhalation, cyanosis, arterial hypoxemia with subsequent accumulation of CO2 and the development of coma, asphyxiation.

According to the observations of V. F. Uchaikin, in the genesis of stenosing laryngotracheitis in children with stenotic laryngotracheitis, allergic mood of the mucous membranes of the larynx and trachea and their hypersensitivity to any stimuli, even to airflow, have a certain value.

The severity of stenosing laryngotracheitis is determined by the degree of narrowing of the lumen of the upper respiratory tract or laryngeal stenosis. There are 4 degrees of stenosis of the larynx. When I degree stenosis, noisy breathing (on inhalation) is detected only when the child is anxious, his physical activity increases; in case of stenosis of the second degree of DN, inspiratory dyspnea, the participation of auxiliary muscles in the act of breathing are detected even during sleep, which becomes restless. 802 does not decrease less than 90%, metabolic acidosis, moderate hypocapnia are detected. When stenosis of III degree, the child almost does not sleep because of the feeling of lack of air, asphyxiation. Dyspnea becomes mixed (inspiratory-expiratory), acrocyanosis appears. The efforts made by the child in the process of breathing are extremely possible (his hair becomes wet from sweat); nevertheless, they do not ensure the balance of gas exchange. There is a decrease in PaO2 <90%, increasing metabolic acidosis, hypocapnia begins to be replaced by hypercapnia. The real threat of exhaustion of the physical forces of the child and the development of asphyxia.

Clinical manifestations of laryngeal stenosis depending on its severity

Power	Symptoms
I	A rough, "barking" cough, hoarseness, noisy breathing in the inspiratory phase. Auxiliary muscles in the act of breathing is not involved, NAM manifests with anxiety of the child
II	The breathing is noisy, audible at a distance, moderate retraction of the pliable chest inhalation. Often there are attacks of shortness of breath, moderately pronounced inspiratory dyspnea observed at rest
III	Breathing is always difficult, shortness of breath is mixed (inspiratory-expiratory), the pliable spaces of the chest and sternum are noticeably drawn in at the moment of inhalation. Constant anxiety, pallor with acrocyanosis, sweating, tachycardia, possible loss of the pulse wave during inhalation. Pronounced ODN
IV	Adynamia, lack of consciousness, spilled cyanosis, decrease in body temperature, shallow breathing or apnea, dilated pupils (hypoxic coma)

[8], [9], [10], [11]

Treatment with stenosis of laryngotracheitis

Treatment of stenosing laryngotracheitis is aimed at removing pre-liquefied mucus from the respiratory tract, reducing edema in anatomically narrow places, reducing muscle spasm. The treatment algorithm is as follows:

1. give oxygen that is humidified and heated to 30–35 ° C in a concentration of 30–40% through a mask or in a tent. In case of mild croup, enough aerotherapy is required; in case of stenosis of the III degree, the child stays permanently in an atmosphere of 30–40% oxygen-enriched air enriched with oxygen (oxygen-vapor tent);
2. Diazepam is administered in a dose of 0.2 mg / kg. With compensated forms of croup, valerian extract can be used: solutions of bromine salts; in case of pronounced edema / laryngeal tissue, inhalations of 0.1% adrenaline solution (or 0.05-0.1% naphthyzin) are applied in a dose of 0.3-1.0 ml, diluted in 3-5 ml of saline, with signs of spasm bronchial muscles can be used inhaled bronchodilators (salbutamol, atrovent, | berodual);
3. maintaining water balance with the help of IT in some cases facilitates sputum discharge. Glucocorticoids (for example, dexamethasone) at the stages of sub- and decompensation of respiratory function are used in a dose of 2-10 mg / kg. Typically, prednisone or dexazone is administered bolus intravenously or intramuscularly.

Tracheal intubation (extended nasotracheal) is carried out with thermoplastic tubes (their diameter should be 0.5–1 mm smaller than the age size).

Indications for tracheal intubation are a decrease in paO2> 60 mm Hg. Art. And an increase in pCO2> 60 mm Hg. Art. The extubation of the trachea is usually done in 2-5 days. The indications for it are the normalization of temperature, the elimination of hypoxemia during respiration by atmospheric air. Possible recurrence of croup due to reactive edema of the larynx with the need for reintubation. In this case, use a tube of smaller diameter (0.5 mm or 1 size).

Indications for tracheostomy are the preservation or progression of hypoxemia in the background of intubation. Maintaining patients with a nasotracheal intubation without complications within 3-4 weeks.

Treatment of croup

The effectiveness of therapeutic measures in acute laryngeal stenosis depends on the timeliness of their use. Intensive treatment of acute respiratory failure should begin with aerosol inhalation with coarse aerosols with high sedimentation. Treatment of laryngeal stenosis I degree symptomatic: administration of sedatives (diazepam 4-5 mg / kg), vapor alkaline inhalations, oxygen therapy with moistened 40% O ₂, dexamethasone 0.3 mg / kg intramuscularly, broad-spectrum antibiotics. With increasing stenosis (II-III degree), therapy begins with intramuscular or intravenous administration of dexamethasone 0.3-0.5 mg / kg or prednisolone 2-5 mg / kg; inhalation corticosteroids (budesonide 1-2 mg or fluticasone 50-100 mcg) are shown using a nebulizer, oxygen therapy with a moist 40-100% O ₂, broad-spectrum antibiotics. Antihistamines are used only for concomitant allergic conditions. In case of IV degree stenosis, stenosing laryngotracheitis begins to be lessened with epinephrine inhalation of 0.1% -0.01 mg / kg (or, in extreme cases, instillation into the nasal passages at a dilution of 1 to 7-10), then dexamethasone 0.6 mg / kg intravenously. With increasing hypoxia - cardiopulmonary resuscitation, intubation, mechanical ventilation, oxygen wet conditions on 100% O ₂. Conicotomy for podskladochnogo stenotic laryngotracheitis, as a rule, is ineffective due to the fact that the stenosis extends below the podskladochnogo space. If tracheal intubation is not feasible, a tracheotomy is performed.

Diphtheria of the pharynx on the background of a progressively progressive laryngeal stenosis is characterized by filmy whitish-yellowish or grayish patches that appear first within the laryngeal vestibule, then in the glottis, leading to the development of stenosis. Submandibular and posterior cervical lymph nodes are sharply enlarged, painful, and the tissues around them are swollen.

Hospitalization is compulsory for any degree of croup, transportation is carried out with the elevated position of the upper torso.

In case of diphtheria of the larynx, there is always an emergency hospitalization in the infectious department during the treatment of acute respiratory failure, depending on the degree of stenosis. Regardless of the stage of the disease, anti-diphtheria serum is immediately administered. The serum dose (15 000 to 40 000 AE) determines the prevalence of the process and the stage of the disease.

[12], [13]