Recently, many researchers paid more attentions to the association between air pollution and chronic obstructive pulmonary disease (COPD). Haze, a severe form of outdoor air pollution, affected most parts of northern and eastern China in the past winter. In China, studies have been performed to evaluate the impact of outdoor air pollution and biomass smoke exposure on COPD; and most studies have focused on the role of air pollution in acutely triggering symptoms and exacerbations. Few studies have examined the role of air pollution in inducing pathophysiological changes that characterise COPD. Evidence showed that outdoor air pollution affects lung function in both children and adults and triggers exacerbations of COPD symptoms. Hence outdoor air pollution may be considered a risk factor for COPD mortality. However, evidence to date has been suggestive (not conclusive) that chronic exposure to outdoor air pollution increases the prevalence and incidence of COPD. Cross-sectional studies showed biomass smoke exposure is a risk factor for COPD. A long-term retrospective study and a long-term prospective cohort study showed that biomass smoke exposure reductions were associated with a reduced decline in forced expiratory volume in 1 second (FEV1) and with a decreased risk of COPD. To fully understand the effect of air pollution on COPD, we recommend future studies with longer follow-up periods, more standardized definitions of COPD and more refined and source-specific exposure assessments.
Objective To systematically review the effectiveness and safety of cordyceps sinensis for chronic obstructive pulmonary diseases (COPD). Methods We electronically searched databases including CBM, CNKI, WanFang Data, VIP, PubMed, Cochrane Central Register of Controlled Trials (Issue 7, 2013) and EMbase for randomized controlled trial (RCT) and quasi-RCTs on the effectiveness and safety of cordyceps sinensis for COPD. According to Cochrane methods, two reviewers independently screened literature, extracted data, assessed methodological quality. Then, meta-analysis was performed using RevMan 5.2 software. Results Fourteen quasi-RCTs involving 1 162 patients were included. The results of meta-analysis showed that: a) compared with routine treatment alone, cultured cordyceps sinensis in combination of routine treatment improved total effective rates (stationary stage: RR=1.33, 95%CI 1.14 to 1.54, P=0.000 3; advanced period: RR=1.36, 95%CI 1.14 to 1.62, P=0.000 8). Also cultured cordyceps sinensis in combination of routine treatment improved lung function (FEV1/FVC: MD=5.48, 95%CI 3.22 to 7.74, Plt;0.000 01; FEV1%: MD=3.75, 95%CI 0.91 to 6.59, P=0.010), and prolonged exercise duration (MD=43.51, 95%CI 27.66 to 59.36, Plt;0.000 01) for COPD patients in stationary stage. However, no evidence was found in blood gas analysis, immune function, and quality of life; and b) the results of one study showed that, cultured cordyceps sinensis in combination of routine treatment was comparable with immune regulator (BCG-PSY) in combination of routine treatment with regards to total effective rates, but it could better improve lung function of patients. Conclusion Current evidence suggests that cultured cordyceps sinensis is effective in treating COPD, especially in treating lung function and exercise duration of COPD patients in stationary stage and increasing total effective rates. However, the strength of evidence is affected by poor methodological quality of the included studies. High-quality trials with large sample size are needed to verify its clinical effects.
ObjectiveTo investigate the effect of pulmonary rehabilitation on pulmonary function,perception of dyspnea and quality of life in stable COPD patients of different severity. Methods300 patients with COPD in stable stage were divided into a moderate COPD group (n=120),a severe COPD group (n=100) and a very severe COPD group (n=80). Each group was randomly subdivided into a control group and a treatment group. The treatment groups received pulmonary rehabilitation for 6 months in addition to usual care,and the control groups received usual care without pulmonary rehabilitation. Pulmonary function(FEV1),6 minute walking distance (6MWD),modified medical research council (mMRC) scale,and acute exacerbation frequency of COPD were compared before and after intervention and among groups. ResultsAfter pulmonary rehabilitation for 6 months,the quality of life score and 6MWD were significantly improved in the treatment groups with moderate,severe,very severe COPD,and the increscent of 6MWD was greatest in the severe COPD patients. The mMRC of the patients with very severe COPD improved significantly after pulmonary rehabilitation(P<0.05). Lung function before and after the intervention in three groups all showed no significant difference (P>0.05). The acute exacerbation frequency of the severe COPD patients was significantly reduced by pulmonary rehabilitation (P<0.05), while there was no significant change in the moderate and very severe groups (P>0.05). ConclusionPulmonary rehabilitation can improve exercise tolerance and quality of life of COPD patients with different severity,reduce acute exacerbation frequency in severe COPD,reduce the dyspnea degree in very severe COPD. Pulmonary rehabilitation is a cost-effective treatment for stable COPD.
ObjectiveTo investigate the expressions of IL-10,tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) in serum and lung tissue of COPD rats in order to elucidate the potential mechanism of airway inflammation. MethodsForty-five healthy adult male SD rats were randomly divided into a COPD model group (n=30) and a normal control group (n=15). The COPD rat model was established by intratracheal instillation of lipopolysaccharide (LPS) and exposure to cigarette smoke for 28 days. The concentrations of IL-10,TNF-α and IFN-γ in serum and lung tissue were measured by ELISA. ResultsTNF-α level of serum and lung tissue in the COPD model group increased significantly compared with the control group(P<0.05),while the levels of IFN-γ and IL-10 decreased significantly[serum:(44.68±8.67) ng/L vs. (75.96±10.59) ng/L;lung tissue:(64.55±9.03) ng/L vs. (94.06±8.71) ng/L,P<0.01]. The level of IL-10 in serum and lung tissue was negatively correlated with TNF-α (serum:r=-0.67,lung tissue:r=-0.80,P<0.01). The level of IL-10 in serum and lung tissue was positively correlated with IFN-γ (serum:r=0.64,lung tissue:r=0.72,P<0.01). The level of IL-10 in serum and lung tissue was negatively correlated with the percentage of neutrophils(serum:r=-0.70,lung tissue:r=-0.67,P<0.01). ConclusionIn COPD rats,down regulation of IL-10 plays an important role in regulation of airway inflammation.
Objective To determine the efficacy and prognosis of noninvasive positive pressure ventilation (NPPV) in exacerbations of chronic obstructive pulmonary disease (COPD). Methods Trials were located through electronic searches of MEDLINE, EMBASE, Springer, and Foreign Journals Integration System (from the start date to March 2008). We also checked the bibliographies of retrieved articles. Statistical analysis was performed with The Cochrane Collaboration’s software RevMan 4.2.10. Results A total of 19 trials involving 1 236 patients were included. Results showed that: (1) NPPV vs. conventional therapy: NPPV was superior to conventional therapy in terms of intubation rate (RR 0.36, 95%CI 0.27 to 0.49), failure rate (RR 0.62, 95%CI 0.43 to 0.90), and mortality (RR 0.49, 95%CI 0.34 to 0.69). The length of hospital stay was shorter in the NPPV group compared with the conventional group (WMD – 3.83, 95%CI – 5.78 to – 1.89), but the length of ICU stay was similar. The changes of PaO2, PaCO2, and pH were much more obvious in the NPPV group compared with the conventional group. The change of respiratory rate was more significant in the NPPV group compared with the conventional group (WMD – 3.75, 95%CI – 5.48 to – 2.03). At discharge and follow-up, there were no significant differences in FEV1, pH, PaCO2, PaO2, and vital capacity between the two groups. (2) NPPV vs. invasive ventilation: the mortality was similar between the two groups. The incidence of complications was lower in the NPPV group compared with the invasive group (RR 0.38, 95%CI 0.20 to 0.73). The length of ICU stay, duration of mechanical ventilation, and weaning time were shorter in the NPPV group than those of the invasive group. At discharge and follow-up, clinical conditions were similar between the two groups. Conclusion The limited current evidence showed that NPPV was superior to conventional therapy in improving intubation rate, mortality, short term of blood-gas change, the change of respiratory rate; and superior to invasive ventilation in the length of hospital stay and the incidence of complication. There were no difference among them in discharge and follow-up.
ObjectiveTo explore the changes of the B lymphocyte-derived microparticles (BLMPs) in the bronchoalveolar lavage fluid in patients with chronic obstructive pulmonary disease (COPD),and analyze the correlation between BLMPs changes and the stages of the disease. Methods33 COPD patients in acute exacerbation and 12 COPD patients in stable phase in Southwest Hospital,Xinqiao Hospital,and First Affiliated Hospital of Chongqing Medical University between March 2012 and March 2013 were enrolled in the study. 31 subjects who underwent physical examination and bronchoscopy were recruited as control. The lavage fluid specimens were collected through fiberoptic bronchoscopy,then marked with the corresponding antibodies after centrifugation. The numbers of microparticles were analyzed by flow cytometry. ResultsThe number of the BLMPs was significant different among three groups (P<0.05). Compared with the control group and the stable COPD group,the number of BLMPs in the AECOPD group was significantly reduced (P<0.05). Compared with the control group,the number of the BLMPs in the stable COPD group was reduced but with no significant difference (P>0.05). The numbers of BLMPs had no correlation with the smoking history,gender,age and body surface area. ConclusionThe number of BLMPs is reduced in COPD,especially in the acute exacerbation stage,so the reductions of the BLMPs may be associated with the stages of the disease. Smoking,gender,age,body surface area have no effect on the number of BLMPs.
Objective To investigate the effects of positive end-expiratory pressure (PEEP) level on end-expiratory lung volume (EELV) during assisted ventilation in chronic obstructive pulmonary disease （COPD） patients，to provide physiological evidence to guide optimal setting of PEEP level in clinical practice.Methods Eight intubated patients with acute exacerbation of COPD were recruited for the study when the patients were in relatively stable condition after treatment.The static intrinsic PEEP (PEEPistat) and dynamic intrinsic PEEP (PEEPidyn) were measured by using airway occlusion method and esophageal balloon-tipped catheter technique,respectively.Changes in EELV (ΔEELV) were measured with inspiratory capacity (IC) method.Relations between PEEP level and ΔEELV were analyzed by curve estimation method.Results ΔEELV as a function of level of PEEP was shown as a sigmoid model.The low inflection points of the curves when PEEP levels were expressed as PEEP/PEEPistat ratio，PEEP/PEEPidyn ratio or actual PEEP setting (PEEP-a) were 0.74，0.76 or 3.6 cm H2O,respectively.The corresponding ΔEELV expressed as ΔEELV/IC（%） were 9.6%，9.1% and 7.4%,respectively.Conclusions In AECOPD patients demanding mechanical ventilation，the changes of lung volume (ΔEELV) in response to progressive increase of PEEP level were shown to be a sigmoid model.Setting PEEP level at 0.74 of PEEPistat，or 0.76 of PEEPidyn can avoid the steep increase of lung volume.
Objective To investigate the therapeutic effects of biphasic positive airway pressure (Bilevel) ventilation and volume ventilation plus [VV+，including volume control plus (VC+) and volume support (VS)] on respiratory failure in patients with chronic obstructive pulmonary disease (COPD).Methods 63 patients with COPD complicated by acute respiratory failure were intubated and underwent mechanical ventilation for at least 24 hours.At the first patients were underwent assist-control (A/C) ventilation for 2 to 4 hours to obtain the suitable basic ventilatory parameters.Meanwhile，the hemodynamics and oxygen dynamic parameters were measured.Then the patients were randomly allocated to three groups with 21 patients in each group and the ventilation mode was switched to Bilevel，VC+ and A/C mode correspondingly.The setting parameter was identical in three modes.In the process of weaning，patients in Bilevel group were ventilated with Bilevel and pressure support ventilation (PSV) mode at each pressure level，and subdivided into Bilevel and PSV 1 group accordingly.In VC+ group，the mode was switched to VS and PSV mode and subdivided into VC+ group and PSV 2 group,respectively.Every mode was run for 30 minutes while the ventilation function，blood gas exchange and lung mechanics index were measured.Results In the initial stage，the airway peak pressure (PIP) of Bilevel and VC+ mode obviously decreased，and the respiratory compliance was higher compared to the A/C mode. The effectiveness of Bilevel and A/C was equivalent in improving alveolar ventilation and oxygenation.The difference in the change of circulation function and blood gas between the two groups were not significant (Pgt;0.05).In the process of weaning，the effectiveness of Bilevel and VV+ was equal to PSV.The changes of breathing mode and blood gas between the two groups had no significant differences.Conclusions Bilevel and VV+ mode ventilation can be used in the whole mechanical ventilation for acute respiratory failure due to COPD with lower PIP，higher respiratory compliance compared to A/C model and similar performance as PSV during mechanical ventilation withdrawn.
Objective To study the effect of noninvasive positive pressure ventilation (NPPV) in chronic obstructive pulmonary disease (COPD) patients with hypercapnic coma secondary to respiratory failure.Methods COPD patients with or without coma secondary to respiratory failure were both treated by bi-level positive airway pressure (BiPAP) ventilation on base of routine therapy.There were 32 cases in coma group and 42 cases in non-coma group.Such parameters as arterial blood gas (ABG)，Glasgow coma scale (GCS)，time of NPPV therapy，achievement ratio，and adverse effects were investigated.Results 30 patients in the coma group were improved after NPPV treatment (26 cases recovered consciousness treated by BiPAP in 2 hours，3 cases recovered between 3~8 hours，1 case recovered after 24 hours).The parameters of ABG，the tidal volume and the minute ventilation volume were improved after BiPAP.The time of effective therapy was (9±4) days in the coma group and (7±3) days in the non-coma group with no significant difference (Pgt;0.05).The achievement ratio was similar in two groups (93.75% vs 97.62%，Pgt;0.05).But the incidence of gastrointestinal tympanites reached to a higher level in the coma group (80.5%) than the non-coma group (10.6%).Conclusion COPD patients with hypercapnic coma secondary to respiratory failure isn’t the absolute contraindication of NPPV treatment.
Objective To explore the distribution of bacteria among community acquired lower respiratory tract infection (LRTI) inpatients with underlying chronic respiratory tract diseases.Methods The clinical data，sputum culture and drug susceptibility results of 212 community acquired LRTI patients who were hospitalized during the period 2001-2005 were retrospectively analyzed.All patients had various underlying chronic respiratory tract diseases.Results A total of 229 strains of pathogens were detected，with the majority being gram negative bacteria.In pathogens of acute exacerbation of chronic obstructive pulmonary disease，gram negative bacteria occupied 73.9%.And Pseudomonas aeruginosa and Klebsiella pneumoniae were the most common pathogens，with each occupying 18.2% and 13.6% respectively.Gram positive bacteria occupied 23.8%，mainly Staphylococcus aureus (10.2%) and Streptococcus pneumoniae (9.1%).In patients with bronchiectasis exacerbated by bacterial infection，86.2% were caused by gram negative bacteria，the top three being，in descending order，Pseudomonas aeruginosa (27.5%)，Haemophilus parainfluenzae (13.7%)，and Haemophilus influenzae (11.8%).Bronchiectasis was the major risk factor of getting Pseudomonas aeruginosa infection (OR=5.590，95%CI 2.792~11.192).The risk factors of getting Acinetobacter baumanii infection were antacid usage within 1 month (OR=9.652，95%CI 2.792~11.192) and hypoalbuminemia (OR=2.679，95%CI 1.108~6.476).For enterobacters infections，including Klebsiella pneumoniae，Enterobacter cloacae and Escherichia coli，the risk factors were antibiotic usage within 1 month (OR=4.236，95%CI 1.982~9.057)，having renal diseases (OR=4.305，95%CI 1.090~17.008) and diabetes mellitus (OR=2.836，95%CI 1.339~6.009).Conclusions Gram negative bacteria were the main pathogens of community acquired LRTI in hospitalized patients with underlying chronic respiratory tract diseases.The pathogens were influenced by underlying diseases，severity of diseases and drug usage history of patients.