Aspiration pneumonia is the infectious and toxic damage of a pulmonary parenchyma developing owing to hit in the lower airways of contents of a mouth, a nasopharynx, a stomach. Aspiration pneumonia is shown by cough, , cyanosis, tachycardia, breast pain, fever, emergence of a fetid phlegm. Diagnosis of aspiration pneumonia is based on auskultativny and radiological yielded, results of a bronkhoskopiya, a microbiological research of contents of the lower airways and a pleural exudate. Treatment of aspiration pneumonia demands performing oxygenotherapy, antibiotic treatment, endoscopic sanitation of a trakheobronkhialny tree; if necessary drainage of the developed abscesses or an empiyema of a pleura is carried out.
Aspiration pneumonia in pulmonology is understood as the pneumonia which resulted from the established episode of casual hit in the lower airways of contents of a rotonosoglotka or a stomach. Among various forms of pneumonia aspiration pneumonia has quite big specific weight: about 23% of cases of severe forms of a pulmonary infection fall to its share. The aspiration syndrome quite often occurs at almost healthy faces during sleep. So, at researches with a nasopharynx irrigation solution, marked radioactive isotopes, aspiration was recorded at 45-50% of healthy people and at 70% of elderly patients 75 years with consciousness violation are aged more senior.
Aspiration pneumonia develops against the background of casual hit of firm particles or liquid in pneumatic ways. Nevertheless, only one fact of aspiration is not enough for developing of aspiration pneumonia. In the mechanism development of pneumonia the quantity of aspirirovanny contents and its character, number of the microorganisms getting into terminal bronchioles, their virulence, a condition of protective factors of an organism plays a role.
In most cases the etiology of aspiration pneumonia has polymicrobic character. More than 50% of cases of aspiration pneumonia are caused by anaerobic flora (bakteroida, prevotelly, fuzobakteriya, porfiromonada, veylonella, etc.); about 10% - only aerobic types (stafilokokka, a hemophilic stick, klebsiyelly, colibacillus, enterobakteriya, Proteus, a sinegnoyny stick); in other cases – the combined flora. As an important microbiological substratum at development of aspiration pneumonia presence at a mouth and the top airways of pathogenic microflora at caries, periodontosis, a gingivita, tonsillitis etc. acts.
Most often serve as a premorbidny background for aspiration pneumonia:
1. The consciousness violations caused by various factors:
- alcoholic intoxication
- general anesthesia
- craniocereberal trauma
- overdose of medicines
2. Diseases peripheral and central nervous system:
- multiple sclerosis
- disease Parkinson
- metabolic encephalopathy
- brain tumors
3. The diseases which are followed by violation of the act of swallowing (dysphagy) and a regurgitation:
- sebesten akhalaziya
- gullet stenosis
- gastroezofagealny reflux disease
- to hernia of an esophageal opening of a diaphragm
4. Injuries and yatrogenny damages:
- traumatic and yatrogenny injuries of airways at wounds
- foreign matters of a trachea and bronchial tubes
- to vomiting of various genesis
- carrying out trakheostomiya, intubation
- endotrakhealny manipulations.
5. At children's age:
- meconium aspiration
- violent feeding of the child
- inhalation of foreign matters in bronchial tubes
The scenario of expansion of events at aspiration of contents in a trakheobronkhialny tree can vary from total absence of violations before development respiratory a distress syndrome, respiratory insufficiency and death of the patient. As the conditions leading to development of aspiration pneumonia serve violations of factors of local protection in airways and pathological character of aspiration masses (quantity, chemical properties and , contamination degree and so forth). Mechanical obstruction of airways, a sharp chemical pneumonitis and bacterial pneumonia act as the main pathogenetic links leading to developing of aspiration pneumonia.
At inhalation of large volume of an aspirat or large firm particles there is a mechanical obstruction of a trakheobronkhialny tree. The reflex arising at the same time protective kashlevy promotes deeper penetration of an aspirirovanny substratum into bronchial tubes and bronchioles that can lead to development of hypostasis of lungs. Mechanical obstruction is followed by development of atelektaz of a lung and stagnation of a bronchial secret against the background of which the risk of infection of a pulmonary parenchyma increases.
In response to aggressive influence of aspirirovanny contents the sharp chemical pneumonitis which is characterized by emission of biologically active agents, activation of system of a complement, release of factors of a necrosis of tumors, tsitokin etc. develops. Further pathological changes in a pulmonary parenchyma are caused by its damage by biologically active agents, but not direct action of an aspirat. Against the background of a reflex bronchospasm, an atelektaz of a part of a lung, decrease in pulmonary perfusion and direct damage of alveoluses the gipoksemiya quickly develops. With accession of a bacterial component respiratory insufficiency, fever, cough increases, i.e. all symptoms of bacterial pneumonia appear. In this stage of aspiration pneumonia the infiltration centers radiological are defined, quite often there are pulmonary abscesses and an empiyema of a pleura.
Symptoms of aspiration pneumonia
Aspiration pneumonia passes stages of a pneumonitis, nekrotiziruyushchy pneumonia, an abstsedirovaniye and an empiyema of a pleura in a clinical current. Unlike a bacterial pulmonary infection, the clinic of aspiration pneumonia is developed gradually and is erased. Within several days after an episode of aspiration can take place subfebrilitt, weakness, dry painful cough. Further thorax pains, fever, tachycardia, cyanosis, allocation of a foamy phlegm with blood impurity at cough accrue . Quite often, already 10-14 days later at aspiration pneumonia there is an abstsedirovaniye of pulmonary fabric and an empiyem of a pleura. At the same time there is productive cough with allocation of a purulent phlegm with a putrefactive smell, a blood spitting, oznoba.
Points the existence in the anamnesis of an episode of aspiration confirmed by fizikalny, radiological, endoscopic and microbiological data to aspiration pneumonia. At survey gipoksemiya signs (short wind, cyanosis, tachycardia), lag of the struck side of a thorax at breath come to light, sometimes - a putrefactive smell from a mouth. For clarification of the reasons which led to aspiration pneumonia except survey of the patient by the pulmonologist and thoracic surgeon, consultation of the gastroenterologist, neurologist, otolaryngologist can be required. The confirming diagnostics includes:
- X-ray. The X-ray analysis of lungs in 2 projections allows to define typical localization of aspiration pneumonia in so-called dependent segments of a lung: back verkhnedolevy and top nizhnedolevy segments (at aspiration of contents in horizontal position) or the lower shares (when finding the patient during aspiration in a horizontal position). Besides, lung atelektaza, the destruction centers in a pulmonary parenchyma, a gas congestion over exudate in a pleura cavity are defined.
- Allocation of the activator. As an important stage of diagnosis of aspiration pneumonia serve bacteriological crops of a phlegm on microflora with definition of sensitivity to antibiotics, and also a bacteriological research of washing waters of bronchial tubes. Therefore with the diagnostic purpose usually resort to carrying out a bronkhoskopiya with a phlegm fence, to capture of washing waters from a trakheobronkhialny tree.
- Blood test. For clarification of weight of a gipoksemiya at aspiration pneumonia the gas composition of blood, blood BRAIDS is investigated. The research of biochemical indicators of blood, crops of blood on sterility, on aerobic and anaerobic bacteria is conducted.
Treatment of aspiration pneumonia
At aspiration of the foreign matters leading to an obturation of a gleam of pneumatic ways urgent endoscopic removal of a foreign matter from a trachea/bronchial tube is shown. Oxygenotherapy - supply of the moistened oxygen, in hard cases – an intubation and IVL is carried out. Antibacterial therapy forms a basis of treatment of aspiration pneumonia. At purpose of antimicrobic medicines sensitivity to them anaerobic and aerobic activators is considered. At aspiration pneumonia usually appoint combinations of several antibacterial medicines (for example, ftorkhinalon or tsefalosporin and metronidazole). Duration of a course of antibacterial treatment at aspiration pneumonia makes 14 days.
In the presence of abscesses in lungs their drainage is carried out, vibration massage, perkutorny massage of a thorax is carried out. If necessary repeated trakhealny aspiration of a secret, sanatsionny bronkhoskopiya and a bronkhoalveolyarny unleavened wheat cake is carried out. Resort to surgical intervention at the organization of abscesses of the big sizes (more than 6 cm), pulmonary bleeding, formation of a bronkhoplevralny fistula. At aspiration pneumonia, the complicated empiyemy pleura, drainage of a pleural cavity is carried out, sanatsionny washings, introduction to a cavity of a pleura of antibiotics and fibrinolitik are carried out. Carrying out open drainage (torakostomiya), plevrektomiya with a lung decortication is possible.
Forecast and prevention
At the small volumes of aspirirovanny contents, a stable general background and timely competent treatment, the forecast at aspiration pneumonia does not cause fears. In case of development of a massive pneumonitis, pulmonary abscesses, an empiyema of a pleura, bronkhoplevralny fistulas, sepsis – the forecast is extremely serious. The lethality at the complicated course of aspiration pneumonia makes 22%.
Considering high risk of aspiration pneumonia among the persons having diseases of nervous and digestive systems it is necessary to carry out treatment of the main pathological state. Fractional food and the sparing diet is recommended to patients with a dysphagy and tendency to aspiration. For prevention of a reflux at patients with a dysphagy, seriously ill patients and postoperative patients it is necessary to raise the head end of a bed at an angle 30-45 °. Special attention should be paid to the patients who are on IVL, probe food. The large role in the prevention of aspiration pneumonia is played by hygiene and timely sanitation of an oral cavity, regular visit of the stomatologist.