2016年 · 第39卷第09期

Since its establishment, the Asthma Group of Respiratory Disease Branch of Chinese Medical Association has done a lot of work for the standardized diagnosis and treatment of bronchial asthma (asthma). In 1993, the first edition of asthma prevention and treatment guidelines in China was compiled, and it was revised in 1997, 2003 and 2008. The "Guidelines for the Prevention and Treatment of Bronchial Asthma (2016 Edition)" published in the column of "Diagnosis and Treatment Plan" in this issue is based on the previously revised guidelines for the prevention and treatment of bronchial asthma in China, with reference to the 2015 Global Asthma Prevention and Treatment Initiative (GINA) report, combined with the research results of evidence-based medicine at home and abroad in recent years (see the appendix of the guidelines for specific methods and evidence quality grading standards), and widely solicited opinions from all parties, which was revised after collective discussion by dozens of experts in China's asthma group. The purpose of this guide is to provide guiding documents for our country's respiratory community, with a view to further standardizing the prevention and treatment of asthma in China.

With the continuous development of modern mechanical ventilation technology, new mechanical ventilation strategies (such as lung recruitment, prone ventilation, etc.) have been applied in clinic to promote the recruitment of collapsed alveoli, correct the imbalance of ventilation/blood flow ratio, improve oxygenation, and save the lives of many critically ill patients. However, positive pressure ventilation itself is contrary to negative pressure respiration in human physiological state, which will inevitably cause damage to alveoli due to excessive positive pressure level, and even lead to serious complications such as alveolar rupture and mediastinal emphysema and pneumothorax. At the same time, unreasonable positive end-expiratory pressure (PEEP) cannot maintain the recruitment of end-expiratory alveoli, and it is difficult to effectively improve the exchange of qi and blood. Moreover, the shear force generated by repeated collapse and recruitment of alveoli during respiration causes fatal damage to alveoli, and secondary biological injury and barotrauma are more harmful. Therefore, there is an urgent need for clinical technology that can calculate trans-pulmonary pressure (trans-pulmonary pressure, Ptp) by dynamically monitoring intrathoracic pressure, so as to perform individualized positive pressure ventilation therapy for critically ill patients. The esophagus itself is mainly a muscular structure. From a physiological point of view, intrathoracic pressure can be effectively transmitted to the esophagus. Therefore, the change of esophagus pressure (Pes) can reflect the intrathoracic pressure to a certain extent, which lays a foundation for clinical dynamic monitoring of trans-pulmonary pressure.

Oxygen therapy was first reported since 1890^[1]Since then, it has become an important respiratory support treatment for acute and chronic respiratory failure and during surgical anesthesia because it can rapidly improve the hypoxic status of patients. There are currently a variety of methods of oxygen therapy, including conventional oxygen therapy (nasal tube and mask oxygen inhalation), non-invasive ventilation, and nasal high-flow oxygen therapy (high flow nasal cannula, HFNC). It is worth noting that compared with other oxygen therapy methods, HFNC has gradually become a partial alternative to noninvasive ventilation or traditional oxygen therapy after continuous clinical application validation in the past 10 years. HFNC has begun to be widely used in China, and now we need to pay more attention to its rational clinical application.

ARDS is a common respiratory critical condition, Berlin Standard 2012^[1]Respiratory failure defined as dense shadows in both lungs within 1 week of clinical onset or new or worsening of respiratory symptoms that cannot be explained by pleural effusion, lobe/atelectasis, or nodules, nor fully explained by heart failure or fluid overload (which requires objective assessment to exclude pulmonary edema due to elevated hydrostatic pressure), whose oxygenation index (PaO₂/FiO₂) Not more than 300 mmHg (1 mmHg =0.133 kPa) and positive end-expiratory pressure or sustained positive airway pressure ≥5 cmH₂O (1 cmH₂O =0.098 kPa). This definition redefines ARDS from four aspects: onset time, chest imaging, causes of pulmonary edema and oxygenation status. The severity of ARDS is classified as mild, moderate and severe based on oxygenation index. The severity of the disease is directly related to the mortality rate^[2]The mortality rate of severe ARDS is even as high as 45%^[1]。 Mechanical ventilation is one of the main methods to improve the oxygenation state of ARDS. As early as 1998, some scholars proposed that the ventilation strategy of small tidal volume and limited plateau pressure can reduce the mortality rate^[3]At present, this protective pulmonary ventilation strategy has been widely recognized, but the choice of positive end-expiratory pressure (PEEP), another major ventilation parameter, is still controversial.

ARDS is an increase in alveolar membrane permeability, pulmonary interstitial and alveolar edema, small airway collapse, and alveolar collapse caused by non-cardiogenic factors within or outside the lung. The main pathophysiological changes were decreased lung volume, decreased respiratory compliance and imbalance of ventilation flow ratio. The clinical manifestations were intractable hypoxemia and progressive respiratory distress. CT showed non-"homogeneous" pulmonary edema, atelectasis and "infant lung" or "small lung". According to Berlin standards^[1], severe ARDS [oxygenation index<100 mmHg (1 mmHg =0.133 kPa)] The mortality rate of patients was as high as 46.1%. Mechanical ventilation is one of the important treatment methods for ARDS. At present, the approved mechanical ventilation methods include pulmonary protective ventilation (low tidal volume, high positive end-expiratory pressure), pulmonary recruitment and prone ventilation. Prostrate ventilation has been paid more and more attention because of its simple operation, no need for expensive instruments and drugs, no increase in medical expenses, and almost no unpreventable fatal complications.

Individualized pulmonary protective ventilation strategy under the guidance of respiratory mechanics is the most important progress in mechanical ventilation treatment of respiratory failure. In the past 20 years, a large number of basic and clinical studies have been conducted around the prevention and treatment of ventilator induced lung injury (VILI). Whether ARDS or severe asthma (or chronic obstructive pulmonary failure) patients, the important goal of mechanical ventilation is to improve ventilation and oxygenation status, reduce respiratory work, and prevent the occurrence of VILI. For ARDS, the purpose of lung protection is achieved by limiting plateau pressure to prevent excessive pulmonary dilatation and avoid repeated collapse of collapsed alveolar areas. The main clinical measures are small tidal volume ventilation combined with high level positive end-expiratory pressure (PEEP)^[1]。 For patients with severe asthma and COPD, the main therapeutic objectives are to reduce airway resistance, reduce dynamic hyperinflation, reduce endogenous PEEP (PEEPi), improve ventilation and prevent the occurrence of barotrauma. Dynamic pulmonary hyperinflation and PEEPi are important pathophysiological links in airflow restriction/airway obstruction diseases, and the degree of cognition of their mechanisms and effects affects clinicians' judgment and treatment of patients' condition. The understanding of PEEPi in airway obstructive diseases is also deeper. Almost all patients with severe COPD and asthma have different degrees of PEEPi whether they are spontaneous breathing or mechanical ventilation. PEEPi is a dynamic evolution process in the above two cases, and its changes need to be frequently evaluated and measured. This article will briefly review the clinical significance of PEEPi from the following aspects.

recruitment maneuver (RM) refers to a kind of operation method in which trans-pulmonary pressure and collapsed alveoli are increased by transient administration of positive airway and intraalveolar pressure significantly higher than conventional during invasive positive pressure ventilation (IPPV)^[1,2]。

With the rapid development of economy and industrialization, as well as the change of people's lifestyle, the prevalence of bronchial asthma (asthma) in China is showing a rapid upward trend, and it has become one of the important chronic airway diseases that seriously endanger people's health. Standardized diagnosis and treatment is the basis for improving asthma prevention and treatment. Since its establishment, the Asthma Group of Respiratory Disease Branch of Chinese Medical Association has done a lot of work for standardized diagnosis and treatment of asthma. In 1993, the first edition of asthma prevention and treatment guidelines was compiled, and then revised in 1997, 2003 and 2008. The Guidelines for the Prevention and Treatment of Bronchial Asthma (2016 Edition) are based on the previously revised "Guidelines for the Prevention and Treatment of Bronchial Asthma" in China, with reference to the 2015 Global Asthma Prevention and Treatment Initiative (GINA) report, combined with the results of evidence-based medicine research at home and abroad in recent years, and widely solicited opinions from all parties. It was revised after collective discussion by dozens of experts in China's asthma group. This guide aims to provide guiding documents for the country's respiratory community to adapt to the needs of today's asthma prevention and treatment efforts.

Mechanical ventilation is an important support for respiratory failure in severe patients. Mechanical ventilation can also de-load the diaphragm leading to ventilator-related diaphragm dysfunction. Previous methods for assessing diaphragm function are difficult to be widely used in clinic because of tedious, invasive or low accuracy. Recent studies have shown that assessment of mechanically ventilated patients' diaphragm by bedside ultrasound can reflect spontaneous breathing ability^[1]。 The purpose of this study was to measure the diaphragm index by bedside ultrasound, compare the changes of diaphragm thickness and function in patients with different mechanical ventilation time, and explore the clinical value of bedside ultrasound on diaphragm dysfunction in patients with mechanical ventilation.

The patient was a 24-year-old male. Routine physical examination X-ray chest radiograph found multiple small nodules, no fever, cough, expectoration and dyspnea. He came to our outpatient clinic in September 2012. Past physical fitness. Physical examination showed no positive signs. Blood routine, C-reactive protein, ESR, Mycoplasma pneumoniae antibody titer, carcinoembryonic antigen, cytokeratin 19, neuron-specific enolase and three times sputum search for acid-fast bacilli were no abnormalities. Spiral CT examination of chest in outside hospital showed diffuse exudative changes, showing "paving stone" sign, and slightly larger mediastinal lymph nodes. Bronchoscopy showed that the trachea and the bronchial lumen within grade 4 were normal, the mucosa was smooth, and no new organisms, foreign bodies and active bleeding were found. Bronchoalveolar lavage was performed in the right upper lobe and the left lower lobe respectively, BALF was clarified, and sent to a large hospital in our city for pathological diagnosis. It showed severe chronic inflammation with a small amount of degenerative substances, PAS staining was positive, and the clinical manifestations were consistent with pulmonary alveolar proteinosis. Two weeks later, he visited the outpatient department of our hospital. High-resolution CT of the chest showed diffuse cluster micronodule aggregation in both lungs, with many tree bud signs and map-like distribution. Mediastinal lymph node enlargement (Figure 1，Figure 2)。 Bronchoscopy was performed again. A large number of ciliated columnar epithelial cells and a few histiocytes were found in BALF smear pathology. There seemed to be protein in tissue cells, and PAS staining was weakly positive. To confirm the diagnosis, thoracoscopy was recommended, but the patient refused further examination because the lesion was not extensive and did not affect daily activities, so clinical observation was recommended. In September 2013, the patient developed dry cough with mild shortness of breath after activity, no obvious expectoration and fever, and came to the clinic again, but no positive signs were found in the physical examination. Blood routine: white blood cells are 12.3×10⁹/L, neutrophil ratio 0.85, hemoglobin 150 g/L, platelet 291×10⁹/L; ESR was 21 mm/1 h; Blood gas analysis showed pH 7.45, SpO₂was 99%, PaO₂was 142 mmHg (1 mmHg =0.133 kPa), PaCO₂31 mmHg; Coagulation and biochemical tests showed no abnormalities. High-resolution CT showed that cluster micronodule aggregation signs were more diffuse and the lesions were progressive (Figure 3,Figure 4,Figure 5,Figure 6)。 Another bronchoscopy showed no new findings. To confirm the diagnosis, after obtaining the patient's consent, video-assisted thoracoscopy was performed, and wedge-shaped tissues were removed from the right upper lobe and the right lower lobe respectively and sent for pathological examination. The postoperative pathological results showed the formation of epithelioid granuloma and caseous necrosis under the bronchiolar mucosa, and the tissue was positive for acid-fast staining (Figure 7，Figure 8)。 Guidelines for Implementing Tuberculosis Prevention and Control Standards in 2008^[1]The standard diagnosis was tuberculosis. The patient was transferred to the local tuberculosis prevention and treatment center for standardized treatment. After 6 months of telephone follow-up, the patient's lung lesions were completely absorbed and the treatment was effective.

The patient was a 29-year-old female. Admitted for "sudden massive hemoptysis 4 h". The patient had active pulmonary tuberculosis in the past and was currently on anti-tuberculosis therapy with no history of hemoptysis. After admission, the chest CT examination in the emergency department showed that the left lung was consolidated, and the left lung and bronchi were filled with bleeding. Bronchoscopic blood drawing and irrigation were performed in the emergency department, and bronchial artery embolization was performed in the emergency department after the patient's vital signs were slightly stable. Intraoperative left bronchial arteriography was performed (Figure 1) shows that the distal branch of the left bronchial artery is thickened and disordered, and the local development is abnormal. Embolization with 350-560 μ m gelatin sponge particles is given; At the end of embolism, gelatin sponge particles mixed with contrast agent were seen drifting to the apex of the lung. Immediately stop the embolism, withdraw the gelatin sponge particles in the catheter, and perform bronchial arteriography to understand the local blood supply (Figure 2), there was abnormal arterial communication between the left branch of the bronchial artery and the left subclavian artery, and the contrast medium entered the left subclavian artery through this abnormal communicating artery, and left subclavian arteriography was performed (Figure 3), it can be seen that a small artery originates from the left subclavian artery and supplies blood to intrapulmonary lesions. An attempt was made to use a microcatheter to superselect this artery and embolize it, but the small artery was at an acute angle with the left subclavian artery. After repeated attempts, the superselection intubation failed, so the operation was ended. After operation, the patient had no symptoms of intracranial and left upper limb ischemia. After treatment with internal medicine hemostasis and vasoconstriction, the patient improved and was discharged, and anti-tuberculosis treatment continued. Within six months of follow-up, the patient did not have hemoptysis again.

Amyopathic dermatomyositis is a special subtype of dermatomyositis that refers to skin lesions with typical dermatomyositis without objective signs of myositis and without abnormalities in laboratory tests such as serum enzymology, electromyography and muscle biopsy^[1]Rapidly progressing interstitial pneumonia with severe respiratory failure is often the main manifestation, and the progression is dangerous and easy to be misdiagnosed as severe pneumonia. extracorporeal membrane oxygenation (ECMO) has powerful oxygenation and carbon dioxide scavenging effects, which can replace cardiopulmonary function for a long time, and can buy time for the diagnosis and treatment of unexplained severe respiratory failure. Dual plasma exchange can efficiently remove pathogenic antibodies by separating plasma twice, which has a certain effect on the treatment of dermatomyositis. In our hospital, extracorporeal membrane oxygenation combined with double plasma exchange was used to treat a critically ill patient without myopathic dermatomyositis complicated with severe respiratory failure. The report is as follows.

Non-invasive ventilation (NIV) technique has a unique advantage because it does not need to establish artificial airway, and has been widely used at present. For patients with acute exacerbation of chronic obstructive pulmonary disease, cardiogenic pulmonary edema, impaired immune function combined with respiratory failure and assisted withdrawal, NIV can not only play a good role in respiratory support, but also reduce the hospitalization mortality, tracheal intubation rate and shorten the hospital stay^[1,2,3,4]。 In the NIV technology, various face masks act as a bridge between the ventilator and the patient, which is the guarantee of the successful implementation of NIV. However, although various improvements have been made in the material, shape, model, headband, and the like of the mask^[5]The mask NIV still has adverse reactions such as nasal and facial skin lesion, oropharyngeal dryness, air leakage, sputum disorder, discomfort, aspiration and stomach flatulence^[1,6]And even cause patient intolerance and ventilation failure. Studies show that the failure rate of face mask-induced NIV can reach 18%^[7], increasing the hospital mortality rate of patients by 3 times^[8]。 In order to improve the performance of NIV and reduce complications, headgear NIV came into being. It uses a newly designed headgear as the connecting device between NIV and patients, which has attracted more and more researchers' attention. However, its efficacy and application indications are still controversial. This article summarizes its research status as follows.

Dead space is the part of breathing where ventilation occurs but does not participate in gas exchange. In the past, the evaluation of dead space ventilation was limited by measurement methods, so it was not widely popularized and applied in clinical practice. In recent years, with the emergence of new measurement techniques such as volumetric carbon dioxide map, the measurement and calculation of dead cavity has become more convenient. This article reviews the recent progress in the calculation of dead space ventilation and its clinical application as follows.

At present, tuberculosis is still one of the main diseases that threaten human health. There are 2 to 3 billion people infected with MTB worldwide. In 2014, there were 9.6 million new cases, and my country accounted for 10% of the total cases. The situation is still grim^[1]。 The increase of drug-resistant tuberculosis and the double infection caused by human immunodeficiency virus (HIV) have brought new challenges to the treatment of tuberculosis, and new cost-effective means of prevention and treatment are urgently needed^[1]And by improving the immune function of tuberculosis patients to enhance the body's ability to fight MTB, it provides a new direction for the prevention and treatment of tuberculosis. Vitamin D has a wide range of functions and is an important immunomodulatory substance. The relationship between vitamin D and tuberculosis is summarized as follows.

allergic asthma is a kind of chronic allergic disease caused by allergens such as pollen, animal dander and dust mites, which is characterized by elevated specific immunoglobulin E (sIgE) levels^[1]About 70% of the world's 300 million patients with bronchial asthma (asthma) have allergic asthma^[2]。 Oral and inhaled glucocorticoids (ICS), short-acting and long-acting β 2-adrenergic receptor agonists (LABAs) and leukotriene modulators (LTMs) are commonly used clinical therapeutic drugs. Although most asthma patients have obviously improved their symptoms after standard treatment, there are still some patients whose symptoms and acute attacks are not well controlled^[3]。 The 2015 Global Asthma Prevention and Treatment Initiative (GINA) pointed out that for patients with moderate to severe allergic asthma with good compliance and correct inhalation medication, if the symptoms and acute attacks are not well controlled after level 4 treatment [medium to high dose ICS and/or LABA + relief medication], anti-IgE antibodies should be considered for treatment on the basis of existing drugs. IgE plays a crucial role in the inflammatory mechanism of allergic asthma. The long-term efficacy and safety of anti-IgE therapy in the treatment of allergic asthma are reviewed below.

At present, drugs are still the main treatment for tuberculosis, but the problem of drug resistance is serious. In-depth research on the drug resistance mechanism and gene targets of tuberculosis bacteria, and the development of new prevention and treatment strategies are necessary to control the spread of tuberculosis and improve the treatment of patients. Biogas molecules mainly include nitric oxide, carbon monoxide and hydrogen sulfide, etc. They have specific enzymatic generation and degradation pathways in organisms, and play important intracellular and intercellular signal transmission functions, so they are also called gas-type signal molecules^[1]。 Bioactive gas molecules, as a class of diffusive messenger molecules, mediate a variety of biological effects in prokaryotes and eukaryotes^[2,3,4]。 Gas molecules are closely related to the metabolic activities and viability of lower organisms, especially prokaryotes, by playing important nutritional and signaling roles^[5,6,7,8]。 There have been many research reports on the role of gas molecules in MTB and tuberculosis, and their research progress is summarized as follows.

A 48-year-old woman, a carton worker, was admitted to the hospital on 21 July 2015 due to "chest tightness for 2 months". Two months ago, the patient had chest tightness in the prechest area without obvious trigger at home, which was aggravated after exertion, and no chest pain. 40 days ago, there was dull pain in the precordial area without obvious trigger, which persisted, without radiating pain, and the pain was not related to body position. There was no cough, expectoration, hemoptysis, night sweats, fatigue, anorexia, weight loss, nausea, vomiting, and fever, so he went to a local hospital and checked "chest CT showed cavity-like changes in the left lower lung, and Aspergillus colonization was considered". The patient has no weight gain or loss since the onset of the disease. "Barrett's esophageal and bile reflux gastritis" was found for 4 years, and it was treated with long-term acid suppressing drugs. Five years ago, physical examination found "cavitary changes in the left lower lung", but it was not treated. Physical examination at admission: body temperature 36.5 ℃, pulse 75 beats/min, blood pressure 130/70 mmHg (1 mmHg =0.133 kPa), breathing 19 beats/min, oxygen saturation 100%, clear consciousness, good spirits, neck and supraclavicular lymph nodes were not swollen, lips were not cyanotic, both lungs were coarse, and wet and dry rales were not heard. Admission diagnosis: (1) Nature of left lung cavity lesion to be investigated: fungal infection? Bacterial infection? (2) Barret's esophagus. (3) Bile reflux gastritis.

"Characteristics of Airway Hyperresponse in Children with Chronic Cough with Different Etiologies" was published in the Chinese Journal of Tuberculosis and Respiratory Medicine, Issue 1, 2015.^[1]One article (hereinafter referred to as "the article"). In this paper, the airway hyperresponsiveness (AHR) of children with cough variant asthma (CVA), upper airway cough syndrome (UACS) and post-infection cough (PIC) was analyzed, supplemented by induced sputum and exhaled nitric oxide (FeNO) detection, so as to understand the characteristics of AHR in children with chronic cough with different etiologies. Benefited a lot after reading it. However, I also feel that the following questions in this article are worthy of discussion.

First of all, I would like to thank readers very much for the "Characteristics of Airway Hyperresponsiveness in Children with Chronic Cough of Different Etiologies" published in the Chinese Journal of Tuberculosis and Respiratory Medicine, Issue 1, 2015^[1]"The question raised in this article (hereinafter referred to as" this article ") is also a hot issue of everyone's concern. The answer to your question is as follows.