Nosocomial pneumonia

Nosocomial pneumonia

In accordance with the currently accepted criteria for nosocomial pneumonia (synonyms: hospital pneumonia, ventilator-associated pneumonia)) include only cases of infection of the lungs that developed no earlier than 48 hours. after admission of the patient to a medical institution. Nosocomial pneumonia (NP), associated with ventilation (NIIV), is an inflammatory lung disease that has developed no earlier than 48 h from the moment of intubation and the beginning of ventilation, in the absence of signs of pulmonary infection at the time of intubation. However, in many cases, the manifestation of nosocomial pneumonia in surgical patients is possible at an earlier time.

Epidemiology of Nosocomial Pneumonia

Nosocomial pneumonia ranks second in the structure of all hospital infectious complications and is 15-18%. The incidence of nonsurgical development in surgical patients after planned operations is 6%, after emergency abdominal operations (inflammatory and destructive diseases) - 15% NP is the most frequent infectious complication in the ICU. NPIVL constitutes 36% of all cases of postoperative pneumonia. The frequency of development of NRIVV is 22-55% in planned surgery with mechanical ventilation for more than 2 days, in emergency abdominal surgery - 34.5%, in ARDS - 55%. The incidence of nosocomial pneumonia in surgical ICU patients who are not ventilated does not exceed 15%. The lethality with NP is 19-45% (depends on the severity of the underlying disease and the volume of the operation). Mortality in PNIVL in purulent-septic abdominal surgery reaches 50-70%, depending on the underlying disease, causative agent and the adequacy of therapeutic tactics. Attributive lethality with NPIVL is 23% or more. The prevalence of NRIVs in a specific ICU for a certain period of time is calculated by the formula:

The frequency of development of NPIVL x 1000 / Total number of IVL-days

Lethality in the course of NRIV depends on the pathogen detected in the department.

Lethality with nosocomial pneumonia associated with artificial ventilation, depending on the pathogen

Pathogens	Mortality,%
Ps. aeruginosa	70-80
Gram-positive bacteria	5-20
Aerobic Gram-negative bacteria	20-50

The etiological structure of nosocomial pneumonia

The spectrum of NP pathogens depends on the "microbiological landscape" of a particular medical institution and the ICU. In addition, the etiological structure of nosocomial pneumonia is affected by concomitant diseases (especially COPD) and the nature of the underlying pathological a process that required the use of mechanical ventilation (traumatic shock with aspiration, severe sepsis, surgical interventions in high-risk patients). In general, with NIIVL, Gram-negative microorganisms predominate in surgical patients, Pseudomonas aeruginosa, Acinetobacter, representatives of the Enterobactriaceae family, are much less likely to identify H. Influenzae. Among gram-positive cocci in the development of nosocomial pemmonias, a special place is occupied by golden staphylococcus, an etiological role significantly superior to S. pneumoniae. In a number of cases (4-6%), fungi of the genus Candida play a role in maintaining pneumonia.

Pathogenesis of Nosocomial Pneumonia Associated with Artificial Ventilation of the Lungs

There are two sources of infection of the patient with ICU:

• exogenous,
• endogenous.

Exogenous sources of infection of the lungs include environmental objects directly or indirectly in contact with the respiratory tract of the patient air, inhaled medical gases, equipment for ventilation (endotracheal and tracheostomy tubes, respirators, breathing circuits, catheters for sanation of the tracheobronchial tree, bronchoscopes), as well as the microflora of other patients and medical personnel.

Endogenous source of infection of the lungs is the microflora of the oropharynx, gastrointestinal tract, skin, urinary tract, accessory sinuses of the nose, nasopharynx, and pathogens from alternative foci of infection.

The highly contaminated secret of the oropharynx penetrates the tracheobronchial tree through microaspiration. The risk of aspiration of the secretion of the oropharynx is increased in patients undergoing ventilation because of the presence of an intubation tube that damages the mucous membrane the envelope of the swallows and the trachea, which disrupts the function of the ciliary epithelium and prevents both spontaneous sputum examination and the swallowing act. Bacterial colonization of the oropharynx increases the risk of developing NPIVL because of the possibility of migration of bacteria near the cuff of the intubation tube.

A major role in the pathogenesis of nosocomial pneumonia is played by the translocation of opportunistic bacteria from the digestive tract. In the gastrointestinal tract of a healthy person, there are a lot of microbes - both anaerobes and aerobes. They support adequate motor, secretory and metabolic functions Gastrointestinal tract It is the anaerobic part of the intestinal microflora that provides colonization resistance and suppresses the growth of a potentially pathogenic aerobic bacterial microflora. However, under the influence of trauma, hemodynamic and metabolic disorders or other pathological conditions develops ischemia of the intestinal wall and motor, secretory and barrier functions of the intestine are disrupted. There is a retrograde colonization of the intestinal microflora of the upper gastrointestinal tract, and, barrier function of enterocytes, translocation of bacteria and their toxins into the portal and systemic bloodstream. Polysystemic multifactorial bacteriological analysis in patients with ICU confirmed that the dynamics of abdominal contamination cavity, gastrointestinal tract, blood flow, and also pulmonary tissue depends on the morphofunctional insufficiency of the intestine.

The development of the infectious process in the lungs can be seen as a result of a violation of the balance between aggression factors that promote getting into the respiratory tract a large number of highly virulent microorganisms, and factors of anti-infection protection. Only in conditions of a critical weakening of the protective factors, pathogens are able to manifest their pathogenicity and cause the development of an infectious process.

Features of Nosocomial Pneumonia in Surgery

• Early development (in the first 3-5 days of the postoperative period - 60-70% of all nosocomial pneumonia)
• Multifactorial infection.
• Difficulties of nosological and differential diagnosis.
• The complexity of prescribing empirical therapy.
• The incidence of IVPVL in patients with purulent-inflammatory foci in the abdominal cavity is 64%.

Causes of high incidence of NT in patients with abdominal sepsis:

• prolonged ventilation,
• repeated operations and anesthesia,
• application of "invasive" medical and diagnostic procedures,
• a pronounced syndrome of intestinal insufficiency, predisposing to the translocation of pathogenic microorganisms and their toxins from the digestive tract,
• the possibility of hematogenous and lymphogenic infection from the septic foci in the abdominal cavity,
• syndrome of acute lung damage associated with abdominal sepsis - "fertile" soil for the development of nosocomial pneumonia.

Factors contributing to the early development of nosocomial pneumonia:

• severity of the condition (high score according to APACHE II),
• abdominal sepsis,
• massive aspiration,
• age over 60 years,
• associated COPD,
• impaired consciousness,
• emergency intubation,
• carrying out a long (more than 72 hours) ventilation,
• use of invasive medical and diagnostic techniques, which increases the risk of exogenous infection,
• development of acute respiratory distress syndrome as a nonspecific response of the lungs,
• inadequacy of previous antibiotic therapy,
• repeated hospitalization for 6 months,
• thoracic or abdominal operations,
• nasotracheal and nasogastric intubation,
• position on the back with the head of the bed lowered (angle less than 30 °).

Diagnosis of Nosocomial Pneumonia

Health. A. Science policy of the american college of chest physians, 2000.

Suspicion of nosocomial pneumonia in the conduct of ventilation should occur if there are two or more of the following symptoms:

• purulent sputum character,
• fever> 38 ° C or hypothermia
• leukocytosis> 11x109 / ml or leukopenia 9 / ml, shifting the leukocyte formula to the left (> 20% of stab or any number of young forms),
• paO2 / FiO2 (respiratory index)

In the absence of the above symptoms, there is no need for further examination, it is advisable to carry out surveillance (level II evidence).

In the presence of two or more of the above symptoms, an X-ray examination is necessary. With a normal radiograph - it is necessary to look for alternative causes of symptoms (level III evidence).

In the presence of infiltrates on the roentgenogram, two tactical options are possible (evidence of level III).

In the presence of infiltrates on the roentgenogram, a microbiological examination should be performed (quantitative methods of endobronchial aspirate, BAL, protected brushes, bronchoscopic methods) and prescribe empirical antibiotic therapy (ABT) Adequate empirical ABT in patients with suspected pneumonia increases survival (level II evidence). In the absence of bacteriological confirmation in the stable state of the patient, ABT can be stopped.

To objectify the evaluation of clinical, laboratory and radiographic data in patients with suspected NIVIL, it is advisable to use the CPIS (Clinical Pulmonary Infection Score)

• Temperature, ° C
  • 3, -3, - 0 points,
  • > 38.5 or
  • > 39 or
• Leukocytes, x109
  • 4-11 - 0 points,
  • 11 - 1 point + 1 point, in the presence of young forms
• Bronchial secretion
  • necessity of sanitation of LDP
  • the necessity of sanitizing TBD> 14 = 1 point + 1 point, if the secretions are purulent
• paO2 / FiO2 mmHg
  • > 240 or PLA / ARDS - 0 points,
• Radiography of the lungs
  • absence of infiltrates - 0 points,
  • diffuse infiltrates - 1 point,
  • localized infiltration - 2 points.
• Microbiological analysis of tracheal aspirate (semiquantitative method 0, +, ++ or +++)
  • no growth or 0 - + - 0 points.
  • ++ - +++ - 1 point + 1 point, when the same microorganism is allocated (Gram staining).

The diagnosis of NIVIL is considered confirmed at 7 or more points on the CPIS scale.

Considering that CPIS is inconvenient in routine practice, its modified version became more acceptable - the Doppler (scale of diagnosis and evaluation of pneumonia severity), which is presented in the table.

Sensitivity of the scale is 92%, specificity is 88%. The score of 6-7 points corresponds to the moderate severity of pneumonia, 8-9 - severe, 10 and more - extremely severe pneumonia. The diagnostic value of the Doppler is proved. Its use is useful for dynamic monitoring of patients, as well as for evaluating the effectiveness of the therapy

Scale of diagnosis and evaluation of the severity of pneumonia

Index	Value	Points
Body temperature, С	3, -3, 3, -3, 3,	0 1 2
Number of leukocytes, x109	, -1, 11 0-17 0 or > 20 sticks > 17.0 or the presence of any number of young forms	0 1 2
Respiratory index of pO2 / FiO2	>300 300-226 225-151	0 1 2 3
Bronchial secretion	+/-	0
+++	2
Infiltrates in the lungs (based on the results of radiography)	Absence of	0
Local	1
Drainage, bilateral, with abscessing	2

Among patients with suspicion of NPIVL, three diagnostic groups

• Group I - diagnosis of pneumonia is reliable in the presence of clinical, x-ray and microbiological criteria As clinical experience shows, a full range of diagnostic signs can be detected in 31% of patients.
• II group is a probable diagnosis of pneumonia, in the presence of only clinical and laboratory or clinical and radiological, or laboratory and roentgenological criteria. This "diagnostic set" can be detected in 47% of patients.
• III group - a dubious diagnosis of pneumonia - there are only clinical, or only laboratory, or only radiologic signs of pneumonia. This diagnostic group is 22% among all patients with suspicion of NPIVL.

Antimicrobial therapy is mandatory for patients with I and II diagnostic groups. With a dubious diagnosis of nosocomial pneumonia, further dynamic monitoring is advisable.

Features of microbiological diagnosis of nosocomial pneumonia

The sampling of the material for microbiological examination must be made before the initiation (or replacement) of antibacterial therapy.

For the collection and microbiological examination of the material from the tracheobronchial tree, the following methods are most commonly used.

Diagnostic bronchoscopy and bromo-valvular lavage

The study is preceded by pre-oxygenation with FiO2 = 1.0 for 10-15 min. The procedure is performed under conditions of total intravenous anesthesia, since the use of local anesthetics is limited, given their possible bactericidal effect. Sampling is carried out from the zone of greatest damage, determined from the data of the radiograph and visually. In the case of diffuse pulmonary infiltration, samples of the material are taken from the middle lobe of the right lung or from the ligament segment of the left lung. The detachable (lavage fluid) of the lower respiratory tract from the internal catheter is placed in a sterile tube and immediately delivered to a microbiological laboratory.

The technique of using a "blind" protected catheter

After a five-minute pre-oxygenation with FiO2 = 1.0, the catheter is most distally inserted through the endotracheal or tracheostomy tube. After this, put forward the internal catheter (with the destruction of the film, which protects the internal catheter from road contamination). Aspiration is performed using 20 ml of a sterile syringe attached to the proximal end of the internal catheter. The device is then removed from the endotracheal tube, and the detachable lower respiratory tract from the inner The catheter is placed in a sterile tube and immediately delivered to a microbiological laboratory.

The diagnostic significance of quantitative cultures of endotracheal aspirates depends on the degree of bacterial contamination and the previous use of antibiotics.

Sensitivity and specificity of quantitative methods of diagnosis of nosocomial pneumonia associated with artificial lung ventilation

Methodology	Diagnostic value, cfu / ml	Sensitivity,%	Specificity,%
Quantitative endotracheal aspiration	105-106	67-91	59-92
"Protected" brush-biopsy	>103	64-100	60-95
BALL	>104	72-100	69-100
"Protected" BAL	>104	82-92	VZ-97
"Protected blind" catheter	>104	100	8,

Bronchoscopic (invasive) methods require the use of special equipment, the attraction of additional personnel and have low reproducibility. "Invasive" diagnosis of NPIVL does not lead to a significant improvement in long-term treatment outcomes.

Criteria for severe course of nosocomial pneumonia

• Severe respiratory failure (BH> 30 per minute).
• Development of cardiovascular failure (SBP
• Body temperature> 39 ° C or
• Violation of consciousness.
• Multiblobal or bilateral damage.
• Clinical signs of organ dysfunction.
• Hyperleukocytosis (> 30x109 / L) or leukopenia (9 / l).
• Hypoxemia (pao2

Antibiotic therapy of nosocomial pneumonia in surgical patients

To assign adequate empirical therapy, the following fundamental factors should be taken into account:

• influence on the alleged etiology of the disease duration of the patient's stay in the ICU and the duration of the ventilation,
• Specific features of the specific composition of NPIVD pathogens and their sensitivity to antimicrobial drugs in a particular medical institution,
• the effect of antimicrobial therapy on the etiologic spectrum of NPIVL and on the sensitivity of pathogens to antimicrobial agents.

Schemes of empirical antibiotic therapy of nosocomial pneumonia in surgical patients

Clinical situation	Mode of antibiotic therapy
Nosocomial pneumonia in patients with surgical department	Cephalosporins of the second generation (cefuroxime), cephalosporins of the third generation, which do not possess antipseudomonas activity (ceftriaxone, cefotaxime), fluoroquinolones (ciprofloxacin, pefloxacin, levofloxacin), Amoxicillin / clavulanate
Nosocomial pneumonia in patients with ICU without ventilator	Third-generation cephalosporins with antipseudomonas activity (ceftazidime cefoperazone), 4th generation cephalosporins, Fluoroquinolones Cefoperazone + sulbactam
Nosocomial pneumoniae without SPON (APACHE II is less than 15)	Third generation cephalosporins with antipseudomonas activity (ceftazidime, cefoperazone) + amikacin Cephalosporins of the fourth generation (cefepime) Cefoperazone + sulbactam Fluoroquinolones (ciprofloxacin)
NPivl + SPON (APACHE II is more than 15)	Imipenem + cilastatin Meropenem Cephalosporins of the fourth generation (cefepime) ± amikacin Cefoperazone + sulbactam

Notes

• With a reasonable suspicion of MRSA, any of the regimens can be supplemented with vancomycin or linezolid.
• At a high risk of aspiration or its verification by clinical diagnostic methods, antibacterial drugs that do not possess activity against anaerobic pathogens, it is advisable to combine with metronidazole or clindamycin.

Causes of ineffectiveness of antibiotic therapy of nosocomial pneumonia:

• unsanitary focus of surgical infection,
• severity of the patient's condition (APACHE II> 25),
• high antibiotic resistance of pathogens NPIVL,
• persistence of problem pathogens (MRSA, R. aeruginosa, Acinetobacter spp, S. maltophilia),
• microorganisms "outside the spectrum" of the action of empirical therapy (Candida spp., Aspergillus spp, Legionella spp., P. carinnii),
• development of superinfection (Enterobacter spp., Pseudomonas spp., fungi, Clostridium difficile),
• inadequate choice of drugs,
• late onset of adequate antibiotic therapy,
• non-observance of the dosing regimen of drugs (the route of administration, single dose, interval between administrations),
• low doses and the concentration of antibiotic in plasma and tissues.

Prevention of Nosocomial Pneumonia

Prevention of NRIV can be effective only if it is carried out in the context of a common infection control system encompassing all elements of the treatment and diagnostic process and aimed at the prevention of various types of nosocomial infections. Here are just some of the activities most directly aimed at the prevention of just nosocomial pneumonia. Such measures as, for example, isolation of patients with infectious complications, introduction of the principle "one sister - one patient", reduction of preoperative period, timely detection and adequate surgical sanitation of alternative foci of infection, certainly play an important role in preventing nosocomial pneumonia, as well as other forms of nosocomial infections, but are more universal in nature and have not been considered in this document.

All the requirements set out in this subsection are based on the results of scientific research and practical experience, take into account the requirements of the legislation of the Russian Federation and international practice data. Here, the following ranking system is used for the extent of their validity.

Requirements that are mandatory for execution and are convincingly substantiated by data of methodologically advanced experimental, clinical or epidemiological studies (meta-analyzes, systematic reviews of randomized controlled trials (RCTs), selected well-organized RCTs). In the text they are marked - 1A.

Requirements that are mandatory for performance and are based on a number of noteworthy experimental, clinical or epidemiological studies with a low probability of systematic errors and a high probability of having a causal relationship (cohort studies without randomization, case-control studies, etc.) and having a convincing theoretical justification. In the text they are marked - 1B.

Requirements that must be enforced by applicable federal or local legislation. In the text they are marked - 1B.

The requirements recommended for performance, which are based on presumptive data from clinical or epidemiological research and have a certain theoretical justification (based on the opinion of a number of authoritative experts). In the text they are indicated by the number 2.

The requirements traditionally recommended for execution, however, there is no conclusive evidence either "for" or "against" their implementation, and experts' opinions differ. In the text they are indicated by the number 3.

The above ranking system does not imply an evaluation of the effectiveness of measures and reflects only the quality and the number of studies, the data of which formed the basis for the development of proposed activities.

Fighting endogenous infection

Prophylaxis of aspiration

• It is necessary to remove invasive devices, such as endotracheal, tracheostomy and (or) enteral (naso-, orogastral, -intestinal) tubes, immediately to eliminate clinical indications for their use (1B).
• With septic acute lung injury (APL) or acute respiratory distress syndrome (ARDS), non-invasive mechanical ventilation is ineffective and life threatening.
• As far as possible, avoid repeated endotracheal intubation in patients on mechanical ventilation (1B).
• The risk of developing NPVIL with nasotracheal intubation is higher than with orotracheal (1B).
• A permanent aspiration of the secret from the supramangular space is desirable (1B).
• Before extubation of the trachea (cuff deflation), it is necessary to make sure that the secret is removed from the supramangular space (1B).
• In patients with a high risk of aspiration pneumonia (located on the IVL, with nasogastric, naso-intestinal tube), the head end of the bed should be raised by 30-45 ° (1B).
• For the prevention of oropharyngeal colonization, an adequate toilet of the oropharynx should be performed - aspiration of the mucus by a special catheter, as well as treatment with antiseptic solutions (eg, 0.12% chlorhexidine bigluconate solution) in patients after cardiac surgery (2) and other patients at high risk for pneumonia (3).

Fighting exogenous infection

Hygiene of the hands of medical personnel

• Hand hygiene is a general term for a range of activities, including hand washing, hand antiseptic and cosmetic care for the skin of the hands of medical personnel.
• In case of contamination, wash hands with water and soap. In other cases, hygienic hand antiseptic with alcoholic antiseptic (1A) should be used. Hygienic hand antiseptic is an antiseptic of the hands of medical personnel, whose goal is to remove or destroy transient microflora.
• It should be hygienic antiseptic hands, even if the hands are visually unclean (1A)

Hygienic hand antiseptic should be carried out:

• before direct contact with the patient,
• before putting on sterile gloves when staging a central intravascular catheter,
• before the placement of urinary catheters, peripheral vascular catheters or other invasive devices, if these manipulations do not require surgical intervention,
• after contact with the intact skin of the patient (for example, when measuring the pulse or blood pressure, shifting the patient, etc.),
• after removing the gloves (1B).

Hygienic hand antiseptic for carrying out manipulations for the care of the patient should be carried out at the transition from the contaminated sites of the patient's body to clean, and also after contact with environmental objects (including medical equipment) located in the immediate vicinity of the patient (2).

Do not apply to the antiseptic hand napkins / balls, impregnated with antiseptic (1B).

Measures to improve hand hygiene should be an integral part of the infection control program in a health care facility and have priority funding (1B).

Care for patients with tracheostomy

Tracheostomy should be performed under sterile conditions (1B).

The replacement of the tracheostomy tube should be performed under sterile conditions, the tracheostomy tubes should be sterilized or disinfected at a high level (1B).

Airway sanitation

When performing the sanation of the tracheobronchial tree (TBD), sterile or clean disposable gloves should be worn (3).

When using open systems for aspiration of the secretion of the respiratory tract, sterile single-use catheters (2) should be used.

Care of respiratory equipment

It should not be without special indications (obvious contamination, malfunction, etc.) to replace respiratory contour when used in one patient based only on the duration of its use (1A).

Before using reusable breathing circuits, sterilize or disinfect them at a high level (1B-B).

It is necessary to remove any condensate in the circuit (1A) in a timely manner.

It is recommended to use bacterial filters when performing mechanical ventilation (2).

To fill the reservoirs of humidifiers, sterile or pasteurized distilled water (1B) should be used.

It is recommended to use heat and moisture filters (TBE) (2).

Closed aspirating systems (ZAS) are designed for sanitation, lavage of the tracheobronchial tree and collection of the separated tracheobronchial tree (TBD) for microbiological analysis in closed mode, i.e., in conditions completely separated from the environment. The purpose of creating such systems was to eliminate the contamination of the lower respiratory tract through the lumen of the endotracheal tube with the "traditional" sanitation of the tuberculosis and reduce the negative effect of the sanation procedure trachea for ventilation parameters under "aggressive" ventilation modes. The closed aspiration system is integrated into the "patient-ventilator" contour between the respiratory filter and the endotracheal tube. If during the ventilation is used active moistening with a stationary humidifier, the system is installed between the endotracheal tube and the V-shaped connector of the respiratory circuit.

Thus, a single closed sealed space is created "ventilator - breathing filter - closed aspiration system - intubation tube - patient". In the distal part of the system there is a vacuum control button and a connector to which the vacuum-aspirator tube is connected and, when necessity, a device for taking tracheo-bronchial aspirates for performing laboratory and microbiological studies. Since the closed aspiration system assumes the protection of the aspiration catheter from contact with the external environment, it is covered with a special protective sleeve, the presence of which excludes the contact of the personnel's hands with the surface of the catheter. At the same time, the air in the protective sleeve (potentially contaminated with the patient's flora), when the catheter is inserted into the intubation tube, is removed to the external environment, and the air that enters from the external environment into the protective sleeve when the catheter is removed from the trachea can, in turn, be contaminated with a flora alien to the patient. Repeated unobstructed movement of air in both directions with repeated episodes of sanitation of the trachea becomes a source of mutual infection of the patient and the environment of separation. Obviously, ideally the air moving from the protective sleeve and back must undergo a microbiological "cleaning". From this point of view, in conditions of ICU it is preferable to use truly closed suction systems that are equipped with their own built-in antibacterial filter, excluding the possibility of mutual contamination of the environment of the ICU and the patient with a pathogenic microflora. The data accumulated on the application of AAS The built-in filter indicates a significant reduction in the number of nosocomial tracheobronchitis and pneumonia associated with ventilation, a significant increase in the mean the timing from the onset of mechanical ventilation to the onset of pneumonia, which can be an effective means of preventing respiratory infections in patients with prolonged ventilation.

ilive.com.ua

Causes, Symptoms and Treatment of Nosocomial Pneumonia

Nosocomial pneumonia is an inflammation that develops in the respiratory system of the body. Disease can appear in a hospital on the second or third day. Patients acquire such ailment due to pathogenic bacteria that live in the walls of medical institutions and have already developed resistance to various drugs.

Features and classification of the disease

Pneumonia of the nosocomial type is one of the most common pulmonary ailments. In addition, this type of disease most often leads to death.The danger of the disease is that the already weakened patient under conditions of inpatient treatment acquires a severe form of pneumonia.

According to the existing classification of the disease, several forms of pneumonia can be distinguished:

1. Vnehspitalnaya - is acquired before entering a medical medical institution.
2. Nosocomial - acquired under conditions of inpatient treatment.
3. Aspiration - occurs due to the ingress of liquids or solid food into the lungs.
4. Form of pneumonia acquired due to severe impairment of immunity.

Pneumonia nosocomial is called hospital (or hospital). Such an ailment is classified according to the severity of development. Subdivided into light, medium and heavy pneumonia. Most often, mild and moderate forms of pneumonia are combined into one group, since the treatment course is almost identical.

The severe course of the disease has quite vivid symptoms and a complex curative picture. The disease develops very quickly, accompanied by intoxication of the body, septic shock, severe respiratory failure. If this form of the disease does not urgently require intensive therapy, the patient will die.

Pneumonia of a nosocomial nature has its own bright symptomatic picture. Its main feature is the appearance on the X-ray of infiltrative foci in 2-3 days after the patient's admission to the hospital bed. But the exception is the fact that the patient could bring with him an infection that could not be detected, as it was in the stage of incubation development.

The definition of nosocomial pneumonia is in particular its development. This kind of ailment develops rapidly, appears fairly quickly and has resistance to many drugs.

Why does the disease occur?

Intrahospital pneumonia appears in a certain category of hospitalized patients. The main factor that provokes the development of an ailment is the immune system defenseless against rather strong and dangerous infectious microorganisms. In the risk group are elderly patients and children, who either lost the majority of protective functions over time, or did not buy them.

The main causes of hospital pneumonia, experts are divided into categories:

1. Mechanical - infection in the pulmonary and respiratory tract due to injury, hardware intervention (breathing tubes, catheters, probes).
2. Aspiration - infection of the secretion of the nasopharynx due to ingress of liquid or solid food into the respiratory system of the body.
3. The spread of infections is not from the foci of the chest.

Hospital pneumonia is developed in inpatients who are mainly in the departments of traumatology and surgery. Pneumonia of this nature can cause patients who have received craniocerebral injuries, serious violations of the musculoskeletal system. In surgical and resuscitation departments, as well as in intensive care units, hospital pneumonia may appear in patients with injuries of the pulmonary system, people connected to the equipment, artificially supporting the functions of the respiratory system.

Any form of nosocomial pneumonia is based on infection. Depending on the period of development, the disease can have various infectious factors that provoke its appearance. Early nosocomial pneumonia appears on the second or fifth days after admission of the patient to the hospital.

The causative agents of this form are multiresistant bacteria with resistance to antibiotics from the piperacillin group, ceftazidime, as well as cephalosporins and fluoroquinolones.

Such pathogens in most cases have a sensitivity to completely normal and affordable antibiotics. Therefore, the prognosis for the general course of treatment and the recovery of the patient is favorable.

The late form of nosocomial pneumonia begins to develop on the sixth day of stay in the hospital. Despite the fact that this form of ailment is usually caused by infectious infection with mutated viruses, the overall prognosis is quite favorable, since there are a number of effective and effective drugs for which these microorganisms have high sensitivity.

Later forms of hospital pneumonia have a difficult course and not such optimistic predictions of specialists, since in most cases they arise because of particularly resistant pathogenic microorganisms that are not sensitive to a variety of effective antimicrobial medicines.

Experts consider the most dangerous microorganism a Pseudomonas aeruginosa. It is she who causes purulent ailments developing in the lungs and other organs. This bacterium is the most resistant to many modern antibacterial agents. It can quickly develop, which leads to a strong intoxication of the entire body and death.

How does the disease manifest itself?

The hospital form of pneumonia has unexpressed symptoms, which do not differ much from manifestations of other ailments of the pulmonary system. Such symptoms can often be "erased" and have no bright manifestations, which greatly complicates early diagnosis of the disease. The most obvious signs of hospital pneumonia can be considered:

1. Temperature increase.
2. Coughing attacks
3. The onset of dyspnea.
4. An increase in the number of leukocytes in the blood.
5. The appearance of phlegm.
6. Severe fatigue and general malaise.
7. The appearance on the X-ray of infiltrative foci.

Each form of the disease has specific signs that can manifest themselves as uncharacteristic pain sensations. If the cause of infection is several types of microorganisms at once, then the overall clinical picture can be modified. At the first stages, there may be signs of difficulty breathing, increased pressure. Then the general intoxication of an organism develops, the subsequent stage causes oxygen starvation of cells of a brain and a lethal outcome.

How to eliminate the ailment?

Diagnosis of hospital, or hospital, pneumonia is often complicated by weak or diverse symptoms. The most reliable methods of determining the ailment are radiology and computed tomography of the respiratory system. Once the diagnosis is accurately established, the specialist assigns a series of studies and analyzes to determine the causative agent.

Treatment of this kind of pneumonia is often complicated by the insensitivity of the causative agent that provoked the disease.

The general medical course consists of the phased use of drugs and their selection in accordance with the characteristics of the patient, since the doctor can not exactly tell and determine which of the antibiotics will work well on the pathogenic microorganism. In addition, treatment is difficult to diagnose. The results of the analysis on the sensitivity to the drugs can be obtained only after a few weeks.

When the microbiological study did not yield positive results, and the causative agent remained unknown, as well as its sensitivity to medicines, a specialist prescribes strong antibiotics with a wide range of effects.

In addition, the main task of the doctor is to support the patient's immune system so that his defenses are activated and able to fight the infection. Therefore, the general recommendations of specialists are reduced to creating good conditions for the patient to quickly restore the body.

The patient is recommended strengthened meals, walks in the fresh air, massage procedures and special gymnastics, if the human condition allows it.

respiratoria.ru

Hospital-acquired pneumonia

Intrahospital pneumonia develops at least 48 hours after hospitalization. The most frequent pathogens are gram-negative bacilli and Staphylococcus aureus; drug resistant microorganisms are a significant problem. The causes are the same as for community-acquired pneumonia, but pneumonia in ventilated patients may also be associated with worsening oxygenation and an increase in tracheal secretion. The diagnosis is suspected on the basis of clinical manifestations and chest X-ray and is confirmed by bacteriological a study of blood or samples taken from the lower parts of the respiratory tract with bronchoscopy. Treatment is done with antibiotics. Hospital nosocomial pneumonia has an unfavorable prognosis, in part this is due to concomitant pathology.

Code for the ICD-10 J18 Pneumonia without specifying the pathogen

Causes of Nosocomial Pneumonia

The most common cause of nosocomial pneumonia is the microaspiration of bacteria that colonized the oropharynx and upper respiratory tract in critically ill patients.

Pathogens and the range of their resistance to antibiotics vary in different institutions and can vary within the same institution in a short period (for example, monthly). In general, the most important pathogen is Pseudomonas aeruginosa, which occurs most frequently in pneumonia, acquired in intensive care, and in patients with cystic fibrosis, neutropenia, early AIDS and bronchiectasis. Other important microorganisms are the intestinal gram-negative flora (Enterobacter, Klebsiella pneumoniae, Escherichia coli, Serratia marcescens, Proteus Acinetobacter) and the sensitive and methicillin-resistant Staphylococcus aureus.

Staphylococcus aureus, pneumococcus and Haemophilus influenzae are more common when pneumonia develops within 4-7 days after hospitalization, and intestinal gram-negative microorganisms with an increase in the duration of intubation.

Preceding antibiotic therapy greatly increases the likelihood of a polymicrobial infection, infections are stable organisms, especially methicillin-resistant Staphylococcus aureus, and Pseudomonas infections. Infection with resistant organisms significantly increases lethality and complicates the course of the disease.

Glucocorticoids in high doses increase the risk of Legionella and Pseudomonas infection.

Risk factors

Endotracheal intubation with artificial ventilation is the greatest common risk; associated with Ventilator pneumonia is more than 85% of all cases, pneumonia occurs in 17-23% of patients on ventilator. Endotracheal intubation disrupts the protection of the respiratory tract, worsens the cough and clearance of the ciliary epithelium and facilitates microaspiration of bacteria-infected secret that accumulates above the inflated cuff of the intubation tube. In addition, bacteria form a biofilm on and in the endotracheal tube, which protects them from antibiotics and host immunity.

In non-intubated patients, risk factors include precedent antibiotic therapy, high pH of gastric juice (due to preventive treatment of stress ulcers) and concomitant cardiac, pulmonary, hepatic and renal failure. The main risk factors for postoperative pneumonia are age over 70 years, surgical intervention on the abdominal or thoracic cavity and dependent functional status.

Symptoms of nosocomial pneumonia

In general, the symptoms of nosocomial pneumonia in non-intubated patients are the same as for community-acquired pneumonia. Hospital-acquired pneumonia in critically severe, mechanically ventilated patients more often causes fever and an increased incidence of respiratory movements and / or cardiac contractions or changes in breathing parameters such as an increase in purulent discharge or worsening of hypoxemia. Non-infectious causes of worsening pulmonary function, for example acute respiratory distress syndrome (ARDS), pneumothorax and pulmonary edema should be excluded.

Forms

Hospital-acquired pneumonia involves pneumonia associated with ventila- tion, postoperative pneumonia and pneumonia, which develops in patients without mechanical ventilation, but hospitalized in hospitals in a state of moderate severity or severe.

Complications and consequences

The mortality associated with hospital pneumonia due to gram-negative infection is approximately 25-50%, despite the availability of effective antibiotics. It is unclear whether death is the result of a major illness or pneumonia itself. The risk of death in women is higher. The mortality from pneumonia caused by Staphylococcus aureus is 10 to 40%, in part because of the severity of the comorbid conditions (eg, the need for mechanical ventilation, elderly age, chemotherapy for malignant neoplasms, chronic pulmonary diseases).

Diagnosis of nosocomial pneumonia

Diagnosis is imperfect. Practically hospital pneumonia is often suspected on the basis of the appearance of a new infiltrate on the roentgenogram of the chest or leukocytosis. However, no symptoms of nosocomial pneumonia, signs or radiographic findings are sensitive or specific for setting diagnosis, since all symptoms can be caused by atelectasis, pulmonary embolism or pulmonary edema and can be part of the ARDS clinical picture. The feasibility of Gram staining, sputum analysis and bacteriological examination of endotracheal aspirates remains questionable, because samples are often contaminated bacteria that are either colonizing or pathogenic, so that a positive culture does not always indicate the etiologic role of the isolated microorganism. Bronchoscopic fecal secretion from the lower respiratory tract is likely to yield more reliable specimens, but the effectiveness of this approach is controversial. The study of mediators of inflammation in bronchoalveolar lavage fluid can play a role in diagnosis in the future; for example, the concentration of soluble a trigger receptor expressed by myeloid cells (this protein is expressed by immune cells during infection) of more than 5 pg / ml can help distinguish bacterial and fungal pneumonia from non-infectious causes of clinical and radiological changes in patients on ventilator. However, this approach requires further research, and the only finding that reliably identifies pneumonia, and the microorganism that caused it, is the culture of the respiratory pathogen, isolated from the blood or from the pleural fluid.

Treatment of nosocomial pneumonia

Some patients may have a pneumonia risk index so low that it is necessary to seek an alternative diagnosis. Nevertheless, the treatment of nosocomial pneumonia is carried out with antibiotics that are chosen empirically, based on the nature of the perception of certain risk factors in the patient and conditions.

Uncontrolled use of antibiotics is the main reason for the development of antimicrobial resistance. Therefore, treatment can begin with the appointment of a wide range of drugs, which are replaced by the most specific a drug effective against microorganisms identified in culture. Alternative strategies for limiting resistance, which have not been shown to be effective, include cessation of antibiotics after 72 hours in patients, whose pulmonary infection rates have decreased to less than 6, and the regular alternation of empirically prescribed antibiotics (eg, 3-6 months).

Inocial antibiotics

There are many regimens, but all should include antibiotics that encompass resistant gram-negative and Gram-positive microorganisms. The choice includes carbapenems (imipenem-cilastatin 500 mg intravenously every 6 hours or meropenem 1-2 g intravenously every 8 hours), monobactams (aztreonam 1-2 g intravenously every 8 hours), or antipseudomonasal beta-lactams (ticarcillin 3 g intravenously with or without clavulanic acid every 4 hours, piperacillin 3 g intravenously with or without tazobactam every 4-6 hours, ceftazidime 2 g intravenously every 8 hours, or cefepime 1-2 g every 12 h), administered alone or in combination with an aminoglycoside (gentamicin or tobramycin 1.7 mg / kg intravenously every 8 hours or 5-6 mg / kg once daily or amikacin 15 mg / kg every 24 hours) and / or vancomycin 1 g every 12 hours. Linezolid can be used in some pulmonary infections, including methicillin-resistant Staphylococcus aureus (MRSA), especially in patients who can not be prescribed vancomycin. Daptomycin should not be used to treat pulmonary infections.

Prevention

Non-invasive ventilation using continuous positive airway pressure (CPAP) or bi-level positive airway pressure (BiPAP) prevents a violation in the protection of the airways that occurs with endotracheal intubation and eliminates the need for intubation in some patients. A semi-vertical or vertical position reduces the risk of aspiration and pneumonia compared to the prone position.

Continuous aspiration of the sublingual secretion through a special intubation tube attached to the aspirator probably reduces the risk of aspiration.

Selective decontamination of the oropharynx (use of local forms of gentamicin, colistin and vancomycin cream) or whole gastrointestinal tract (using polymyxin, aminoglycosides or quinolone and / or nystatin, or amphotericin) is also likely to be effective, although it may increase the risk of colonization by resistant organisms.

Hospital-acquired pneumonia is prevented by monitoring culture and routinely replaceable ventilation loops or endotracheal tubes.

ilive.com.ua

Nosocomial pneumonia: pathogens, treatment and prevention

Nosocomial pneumonia is an acute infectious process that occurs in the body under the influence of the active vital activity of pathogenic bacteria. The characteristic features of the disease is the defeat of the respiratory tract of the pulmonary department with internal accumulation of a large volume of fluid. The exudate subsequently seeps through the cells and penetrates into the renal tissue.

Updated national recommendations for nosocomial pneumonia

Since 2014, the Respiratory Society has presented clinical recommendations to the world. They are based on the algorithm of diagnosis and therapy in situations where it is suspected that the patient is progressing through nosocomial pneumonia. National recommendations were developed by specialists, practicing doctors, to help medical personnel who encounter acute respiratory infections.

In short, the algorithm consists of four points.

1. Determination of the need for hospitalization of the patient. A positive decision is made if the patient has a clearly expressed respiratory failure, there is a decrease perfusion of tissues, acute autointoxication, impaired consciousness, unstable blood pressure. For placement in a hospital it is enough to determine at least one symptom.
2. Determine the cause of the disease. For this purpose, the patient is assigned a number of laboratory studies of biological materials: culture sowing blood from the vein, sputum bacillus, high-speed test for determining bacterial antigenyura.
3. Definition of the term of treatment. Provided that the disease is of bacterial origin, but the true cause is not established, the therapy is carried out for ten days. With various complications or extrapulmonary localization of the focus, the therapeutic course can be up to 21 days.
4. Necessary measures of inpatient stay. In severe condition, patients need respiratory or non-invasive ventilation.

Preventive measures are also prescribed in national recommendations. The most effective is the vaccination against influenza and pneumococcus, prescribed mainly to patients with chronic pneumonia and people of the older age group.

Features of Community-acquired Pneumonia

Community-acquired nosocomial pneumonia has another common name - out-of-hospital. The disease is caused by an infection of bacterial etiology. The main path of infection is the environment. Accordingly, the definition will be as follows: inflammatory lesion of the pulmonary department, obtained by airborne by way of, before the patient had contact with the carriers of infection in medical institutions.

Community-acquired and nosocomial pneumonia of bacterial origin is more often diagnosed in patients with reduced immunity, when the body is unable to resist pathogenic microorganisms (pneumococci, Haemophilus influenzae, Klebsiella). They penetrate into the lung cavity through the nasopharynx.

The risk group includes children of younger age group and patients with chronic pathologies of the lungs. In this case, the causative agent is Staphylococcus aureus.

Community-acquired nosocomial pneumonia: principles of classification of the disease

To develop the right treatment, pneumonia is classified according to the following parameters:

• disease, not accompanied by a decrease in the protective function of the body;
• a disease that has arisen against a background of low immunity;
• a disease that occurred in the acute stage of AIDS;
• a disease formed in conjunction with other diseases.

As a rule, the diagnosis is confirmed in patients who have a problem in the form of reduced immunity against the background of oncology or hematology. Also at risk are patients who have been taking high-dose glucocorticosteroids for a long time. There are also situations where the disease occurs in patients with chronic immune pathologies.

In addition, a separate category includes this type of pneumonia, aspiration.

Doctors note that at this point in the mechanism of origin of any kind of aspiration pneumonia there are foreign bodies in contact with which the disease develops.

Features of nosocomial pneumonia

In this concept, physicians invest such a state of the patient when the inflammatory process in the pulmonary department manifests itself approximately 72 hours after infection. The danger is that nosocomial nosocomial pneumonia has a complicated course and most often ends in a lethal outcome. It is caused by bacteria that live in the walls of the medical institution, resistant to most medications, so it is very difficult to find the first time the correct antibiotic.

Intrahospital Nosocomial Pneumonia: Principles of Classification of Disease

Priority nosocomial pneumonia hospital type is classified at the stage of infection:

1. Early stage - in the first five days of the patient's stay in the hospital, obvious signs of illness begin to appear.
2. The late stage - the manifestation of symptoms is prolonged for more than five days.

Depending on the etiology of the development of the disease, three types are distinguished:

1. Aspiration nosocomial pneumonia.
2. Postoperative.
3. Fan-associated.

It is worth noting that the presented classification by type is conditional, and in most cases pneumonia is diagnosed in a mixed form. This, in turn, significantly burdens the patient's condition and reduces the chances of recovery.

Aspiration

The presented form of the disease is the most common. When the infected mucus of the nasopharynx enters the pulmonary department, self-infection occurs.

Liquid nasopharyngeal - an ideal place for pathogenic bacteria food, so, once in the lungs, the microorganisms begin to actively proliferate, and that contributes to the development of aspiration pneumonia.

Postoperative

The presented type of pneumonia is diagnosed in 18 clinical cases out of 100 and is found exclusively in patients who underwent surgery.

In this case, the infection occurs in the same way as in aspiration pneumonia, only to nasopharyngeal fluid is added and gastric secretions, which is no less dangerous. Also, do not exclude the infection of the patient with medical instruments and apparatus. Through a probe or catheter, the infection can easily spread to the lower respiratory tract.

Ventilator-associated

Diagnosed in patients who are in a prolonged time in conditions of artificial ventilation. A safe period is not more than 72 hours of stay in this state, and then the risk of developing pneumonia increases every day.

Pathogens of nosocomial pneumonia

Nosocomial hospital pneumonia is more often caused by pneumococci. Such diagnoses range from 30 to 50 percent of all clinical cases.

The least aggressive bacteria are chlamydia, mycoplasma and legionella. Under their influence, pneumonia develops in no more than 30% of cases, but not less than 8%.

The least common is a disease that arose against the backdrop of active activity: a hemophilic rod, Staphylococcus aureus, Klebsiella and enterobacteria.

Another pathogen of nosocomial pneumonia is influenza A and B, parainfluenza, adenovirus, respiratory syncytial virus.

The most frequent pathogens of nosocomial pneumonia of aggressive type, capable of producing epidemic outbreaks, are mycoplasma and legionella. In the first case, adolescents and young people up to 25 years are most often ill. And infection with legionella occurs through water, for example, in the public shower, swimming pool and so on.

Methods of modern diagnostics

If a patient has an out-of-hospital pneumonia, it is often diagnosed during medical examination. In each clinical case, for the convenience of monitoring the patient's condition and the symptoms of the disease, a separate card or history of the disease is established.

Step-by-step outpatient diagnosis is as follows:

• Radiography of the chest - the method of radiation diagnosis, which in the pictures projects the state of the lungs in several planes. In the presence of dark, dense spots, the diagnosis is confirmed. Diagnosis is shown twice: at the beginning of treatment and after antibiotic therapy.

• Laboratory tests - the patient will need to donate blood for a general analysis and determination of the number of leukocytes, glucose and electrolytes.
• Microbiological studies - the analysis of pleural fluid and the coloring of the lower respiratory tract is performed, and the presence of antigens in the urine is determined.

The results of these diagnostic procedures are sufficient to establish a definitive diagnosis and develop a treatment plan.

Recommendations for treatment of patients

Clinical recommendations for the treatment of nosocomial pneumonia are the primary purpose of a broad-based antibiotic.

After receiving the results of the examinations in the competence of the doctor to change the previously prescribed drug to a more effective one. The type of pathogenic microorganisms is taken as a basis.

Principles of therapy for patients with nosocomial pneumonia

Treatment of nosocomial pneumonia consists in the selection of the correct antibiotic, the regimen for its administration, the mode of administration and dosage. This is only the attending physician. Also an integral part of therapy is the procedure for the sanitation of the respiratory tract (excretion of the accumulated fluid).

An important point is finding the patient in a state of motor activity. It is necessary to perform respiratory gymnastics and small physical activities in the form of squats. Patients in serious condition are assisted by nurses. They are engaged in a regular change in the patient's position, which allows not to stagnate liquids in one place.

Prevent a recurrent disease will help prevent nosocomial pneumonia, which in detail will tell the doctor in charge.

Antibiotic therapy

Treatment aimed at combating bacteria has two types: purposeful and empirical. Initially, all patients undergo an empirical type of treatment, and the directed one is assigned after the pathogen has been determined.

The most important conditions for recovery are:

1. Developing the right antibacterial treatment.
2. Reducing the use of antimicrobials.

To pick up antibacterial medicines, and also their dosage can only the attending physician, independent replacement of preparations is inadmissible.

Prognosis for recovery

Depending on the correctness of the selected drugs, the severity of the disease and the general condition of the patient, the outcome of the treatment may be the following: recovery, minor improvement in the condition, ineffective therapy, relapse, death.

With nosocomial pneumonia, the likelihood of a lethal outcome is significantly higher than that of a community-acquired form.

Preventive measures

Prevention of nosocomial pneumonia is represented by a complex of medical and epidemiological measures:

• timely treatment of concomitant diseases;
• compliance with hygiene rules and norms;
• reception of immunomodulating agents;
• vaccination.

It is very important when improving the patient's condition - in order to prevent relapse - to monitor the observance of simple rules: regular sanitation of the oral cavity, expectoration of the accumulated fluid, physical activity.

fb.ru

Similar articles