Hospital-acquired pneumonia

Hospital-acquired bacterial pneumonia is the most common pathogens, accounting for more than 90 percent, fungi, viruses and other pathogens less see. For one-third of mixed infection. 3% ~ 26% NP caused by Staphylococcus aureus. Streptococcus pneumoniae pneumonia in hospitals has been a marked decrease in the 1970s accounted for about 31 percent in recent years dropped to less than 3%. Enterococcus pneumonia rare, but many more serious condition, the resistance rate is high and treatment difficult. Gram-negative bacillus NP pathogen of the 50% to 80%, mainly Enterobacteriaceae bacteria and non-fermented bacteria. Enterobacteriaceae in a pneumoniae and Escherichia coli is a common, but the separation of a downward trend; cloacae bacilli resistant rates high, incidence increased in recent years, or even become a major epidemic strains ICU; al-Shara of pollution can lead to breathing apparatus NP Outbreak. Non-fermented bacteria, Pseudomonas NP caused by about 10% to 35%, more common in COPD, artificial airway mechanical ventilation or in patients with immune dysfunction, has become the first NP common pathogenic bacteria, Pseudomonas onion, Pseudomonas putida and Acinetobacter than the toxicity of Pseudomonas aeruginosa, the main cause pneumonia in patients with immune suppression. NP in the past that influenza bacilli rare, but in recent years, reports intubation after 48 to 96 hours in regular bacteria cause pneumonia. Legionella pneumonia for more than sporadic cases, the national statistics on the incidence of its less. Anaerobic bacteria caused by the NP rare, but the individual reports of up to 35 percent. China's TB infection rate of the general population and high incidence of TB is a long incubation period, the tuberculosis hospital often difficult to determine for hospital infection. 0% to 5% of the NP caused by the fungus, Candida the most common, accounting for more than 80 percent, followed by the aspergillus fungus infection and hair. Respiratory syncytial virus and influenza A virus can cause NP outbreak, more common in infants and young children wards; adult sporadic cases in order to cytomegalovirus is important, often accompanied immune suppression. Pneumocystis carinii infection rare, almost all occurred in AIDS and organ transplant patients, such as immunosuppression.

[Popular features:

According to the National Hospital of monitoring data, NP is China's most common type of hospital infection, it is estimated that the incidence rate of 1.30 percent to 3.45 percent, in Europe and the United States and other developed countries also ranked two to three. A global scale NP the overall incidence rate of 0.5% to 5.0%. Literature in the incidence of the NP, the teaching hospital of non-teaching hospitals twice; ICU is several times to the general wards a few times chest and abdominal surgery is surgery the other 38 times; non-mechanical ventilation mechanical ventilation 7 to 21 times. Bone marrow transplant patients in the United States NP incidence of 20 percent in real terms, organ transplantation after the first three months of 4 percent in bacterial pneumonia, of which 22% of heart and lung transplant, liver transplant 17%, 5% of heart transplantation, renal transplantation 1% to 2% . NP mortality was 20 percent to 50 percent, significantly higher than community-acquired pneumonia of 5% to 6.3%. Patient deaths and about 15% of lung infection. Died of infection cases in the NP 60 per cent.

[The mechanism]

Oropharynx Colonization NP is the aspiration of the main pathogenesis. 50 percent to 70 percent of healthy people sleep when I could have inhaled throat secretions of lower respiratory tract. Swallowing and coughing reflex such as the weakening or disappearance of old age, disturbance of consciousness, esophageal disorders, tracheal intubation, nasogastric tube, and delayed gastric emptying it easier to reduce tension in aspiration. GNB pharynx into the normal population of less than 5 percent rate of separation, the hospital significantly increased after the bacteria colonization. We have investigating 116 cases of elderly patients, oropharyngeal GNB admission rate from 24.2 percent, after the hospital increased to 50.8 percent; Staphylococcus aureus and fungi respectively from 2.4% and 1.7% to 10.4% and 8.4%. GNB colonization who have pneumonia rate was 23 percent, without colonization, only 3.3 percent. GNB colonization factors have increased the severity of the illness, antibiotics, gastric reflux, major surgery, coma, COPD, the reduction of grain, such as acid poisoning. Except bacteria-into the stomach cavity of reverse colonization of bacteria may be an important source of pathogens oropharyngeal and channels. Usually gastric pH of 1.0, stomach cavity to maintain sterile state. If the acidity of gastric juice dropped only acid and H-2 receptor blockers, old age, alcoholism, gastrointestinal disease, malnutrition and acceptance nasal feeding, stomach bacteria colonization increase. Gastric pH> 4.0 bacterial detection rate was 59%, pH ≤ 4.0, only 14 percent. Patients after surgery to our survey also found that gastric juice from pH 2-8, stomach bacterial colonization rate from 13.3 percent to 100.0 percent, the average concentration from 103.0 to 106.3 CFU / ml. NP bacteria cause stomach may be the mechanism for direct aspiration of gastric juice may also reverse colonization of bacteria in the mouth first pharynx, trachea, and then pneumonia caused by inhalation.

Inhalation Aerosol is infected another pathogenesis of the NP. Atomizer report had led to pollution NP outbreak. Wetlands of the oxygen bottles of water pollution caused NP can not underestimate the danger, we found that its microbial contamination rate of 45 percent, some bacteria concentration of 106 CFU / ml. Is generally believed that in the paediatric wards of hospitals in the pneumonia virus through coughing, sneezing or even talk, aerosol spread of respiratory spread. Legionella bacteria contamination by the shower water and air-conditioning condensation of water can produce aerosols cause NP. Suction bacteria in the course of the direct cultivation should not be overlooked. Disseminated blood, caused by NP less, more common in the lower immune function, severe abdominal infection, the large area of skin burn easily, such as bacteremia in patients.

[Note: the diagnosis

Clinical manifestations are fever, cough, short breath, lung and other audio-moist, but other diseases are often covered up. Early diagnosis depends on the high degree of vigilance of the NP, high-risk groups such as the elderly, COPD, low immune function, chest and abdominal surgery, artificial airway mechanical ventilation, there is unknown or longer duration of fever or heat changes; Increase the symptoms of cough or sputum, or increase or Nongxing sputum smear; oxygen therapy patients required oxygen concentration increased, mechanical ventilation or the amount needed for the increase in minute ventilation, may be suspected NP, the combination of wet-lung - And X-ray showed infiltration or a new inflammatory lesions, in other diseases, except on the basis that under the diagnostic criteria, to make a clinical diagnosis of the NP. NP is the choice of the etiology of anti-infection treatment programme and decided the key to success, as oropharyngeal normal flora pollution, the general sputum culture can not correctly reflect the true pneumonia pathogens. Chinese Medical Association Institute of Respiratory Diseases of the NP develop diagnostic criteria on how to identify the pathogen pneumonia in detail the provisions for reference.

Table 17-9 hospital-acquired bronchial - lung infection diagnostic criteria

Admission 48 hours after the onset, a cough, sputum, or expectoration characters change and meet the following criteria:
1. Fever, lung-sound, or X-ray at the hospital, revealed that the new inflammatory lesions.
2. The selection of two consecutive sputum isolated from the same pathogen. Who will be qualified for the specimens sent to the laboratory within 10 minutes for washing and quantitative sputum culture, isolated from the pathogen concentration ≥ 107 FU / ml.
3. Positive blood culture or pneumonia complicated by pleural exudate puncture extract of the isolated pathogens.
4. Access to any of the following methods of training results can be considered non-polluting bacteria: Fiberbronchoscope or artificial airway to the acquisition of respiratory secretions isolated concentration of ≥ 105 CFU / ml of pathogens, or as part of a film to puncture, or Anti specimens brush the fibers bronchoscopy or artificial airway to the acquisition of pathogens isolated from the respiratory secretions. For patients with chronic obstructive pulmonary disease its concentration of bacteria must be ≥ 103 CFU / ml.
5. Respiratory secretions to the special pathogens in check, or respiratory secretions, serum and other body fluids by the immunological detection methods that organized or pathological evidence.

[*] Note airway disease, known as confined to hospital-acquired trachea - bronchitis, a pulmonary inflammation, known as the essence of pneumonia in hospitals

[Note: Treatment

Including anti-infection therapy, respiratory therapy such as oxygen and mechanical ventilation, immune therapy, support and treatment of sputum drainage, so as to the most important anti-infection treatment. "Clinical experience" is the initial treatment programme based on the principal. Inhibit the immune function, or ICU patients with COPD, a Pseudomonas aeruginosa pneumonia Most of their treatment should include a role in the killing of antibiotics such as penicillin type of piperacillin and ticarcillin, third-generation cephalosporins Ceftazidime and cefoperazone, other β-lactam assigned to the imine and aztreonam, aminoglycoside such as amikacin and fluoroquinolones such as ofloxacin and cyproterone Stars such as sand. Extensive burns or severe trauma complicated by NP, Staphylococcus aureus infection, the drug should be added to the election oxacillin or the first generation cephalosporins, such as methicillin-resistant Staphylococcus aureus, vancomycin should be elected. Benedict weight or illness developed rapidly, the selected drugs to the negative and gram-positive bacteria are killed suitable role of broad-spectrum antibiotics. Organ Transplant taking cyclosporine during the NP and check negative bacteria and fungi, should be suspected of Pneumocystis carinii infection may be, empirical treatment may compound sulfamethoxazole or pentane acetamiprid.

Anti-infection treatment courses see "bacterial pneumonia."

[Note: the prevention

Selective decontamination of antimicrobial drugs that selectively remove potential pathogens without affecting the digestive tract anaerobic bacteria, such as spray to the oral antibiotic ointment or coating of antibiotics, oral absorption of not polymyxin, amphotericin B And so on. NP SDD can reduce the incidence more than 50 percent, but there are induced by drug resistant strains of dangerous, should be limited to high-risk groups. Stress ulcer prevention should be used when the acidity of gastric juice had no effect on the drugs such as sucralfate and avoid the H2-blockers and only acid to keep the stomach cavity of the sterile status. Nasal feeding nutrition can cause stomach bacteria colonization and to increase gastric reflux, recently there have been reports of nasal feeding acidification can significantly reduce bacterial colonization stomach cavity. Can inhibit the respiratory center to avoid the use of the sedative medicine, cough medicine. On unconscious patients to regularly attract oral secretions to reduce inhalation.

Ventilator-associated pneumonia prevention: ① ventilator-loop pipes for use after 48 hours should be replaced. ② loop pipeline on the condensate high concentration of bacteria, to avoid liquidation inverted into the airway. ③ mouth suction tube connected filter bacteria; maintain good indoor ventilation environment may reduce exhaled air carrier aerosol effects on the surrounding crowd. ④ breathing machine on the atomizer temperature of the transfer should not be less than 45 ℃ to reduce bacterial contamination, should be thoroughly disinfected after use.

The hands of medical staff often GNB and Staphylococcus aureus colonization, the proper hand-washing methods and rules can reduce the spread of pathogens. The reduction of grain cells, organ transplantation, and other high-risk groups, should adopt protective isolation techniques such as resettlement in the laminar flow room, medical staff entered the room when the disease with masks, hats and wearing sterile Geli Yi. Bacteria in the vaccine to prevent pneumococcal pneumonia on the more obvious effects, in recent years have used more price Pseudomonas pneumonia vaccine to prevent such a report.