Acute exacerbations and respiratory failure in chronic obstructive pulmonary disease

A role for heat shock factor 1 in hypercapnia-induced inhibition of inflammatory cytokine expression

Hypercapnia, elevated levels of CO₂ in the blood, is a known marker for poor clinical prognosis and is associated with increased mortality in patients hospitalized with both bacterial and viral pneumonias. Although studies have established a connection between elevated CO₂ levels and poor pneumonia outcomes, a mechanistic basis of this association has not yet been established. We previously reported that hypercapnia inhibits expression of key NF-κB-regulated, innate immune cytokines, TNF-α, and IL-6, in LPS-stimulated macrophages in vitro and in mice during Pseudomonas pneumonia. The transcription factor heat shock factor 1 (HSF1) is important in maintaining proteostasis during stress and has been shown to negatively regulate NF-κB activity. In this study, we tested the hypothesis that HSF1 activation in response to hypercapnia results in attenuated NF-κB-regulated gene expression. We found that hypercapnia induced the protein expression and nuclear accumulation of HSF1 in primary murine alveolar macrophages and in an alveolar macrophage cell line (MH-S). In MH-S cells treated with short interfering RNA targeting Hsf1, LPS-induced IL-6 and TNF-α release were elevated during exposure to hypercapnia. Pseudomonas-infected Hsf1^+/+ (wild-type) mice, maintained in a hypercapnic environment, showed lower levels of IL-6 and TNF-α in bronchoalveolar lavage fluid and IL-1β in lung tissue than did infected mice maintained in room air. In contrast, infected Hsf1^+/- mice exposed to either hypercapnia or room air had similarly elevated levels of those cytokines. These results suggest that hypercapnia-mediated inhibition of NF-κB cytokine production is dependent on HSF1 expression and/or activation.-Lu, Z., Casalino-Matsuda, S. M., Nair, A., Buchbinder, A., Budinger, G. R. S., Sporn, P. H. S., Gates, K. L. A role for heat shock factor 1 in hypercapnia-induced inhibition of inflammatory cytokine expression.

Risk factors predict frequent hospitalization in patients with acute exacerbation of COPD

Purpose

COPD is a heterogeneous disease, and the available prognostic indexes are therefore limited. This study aimed to identify the factors associated with acute exacerbation leading to hospitalization.

Patients and methods

This was a retrospective study of consecutive patients with COPD (meeting the Global Initiative for Chronic Obstructive Lung Disease [GOLD] diagnostic criteria) hospitalized at the Ninth Hospital of Xi’an Affiliated Hospital of Xi’an Jiaotong University between October 2014 and September 2016. During follow-up after first hospitalization, the patients who had been rehospitalized within 1 year for acute exacerbation were grouped into the frequent exacerbation (FE) group, while the others were grouped into the infrequent exacerbation (IE) group. The baseline demographic, clinical, laboratory, pulmonary function, and imaging data were compared between the two groups.

Results

Compared with the IE group, the FE group had lower forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) (P=0.005), FEV_1%pred (P=0.002), maximal mid-expiratory flow (MMEF_25–75%pred) (P=0.003), and ratio of carbon monoxide diffusion capacity to alveolar ventilation (DLCO/VA) (P=0.03) and higher resonant frequency (F_res; P=0.04). According to generations of bronchi, the percentage of the wall area (%WA) of lobes was found to be higher in the FE group. Emphysema index (EI), mean emphysema density (MED)_whole and MED_{left lung} in the FE group were significantly worse than in the IE group (P<0.05). Using logistic regression, exacerbation hospitalizations in the past year (odds ratio [OR] 14.4, 95% CI 6.1–34.0, P<0.001) and EI >10% (OR 2.9, 95% CI 1.2–7.1, P=0.02) were independently associated with frequent acute exacerbation of COPD (AECOPD) hospitalization.

Conclusion

Exacerbation hospitalizations in the past year and imaging features of emphysema (EI) were independently associated with FE hospitalization.

Variability in Tidal Volume Affects Lung and Cardiovascular Function Differentially in a Rat Model of Experimental Emphysema

In experimental elastase-induced emphysema, mechanical ventilation with variable tidal volumes (V_T) set to 30% coefficient of variation (CV) may result in more homogenous ventilation distribution, but might also impair right heart function. We hypothesized that a different CV setting could improve both lung and cardiovascular function. Therefore, we investigated the effects of different levels of V_T variability on cardiorespiratory function, lung histology, and gene expression of biomarkers associated with inflammation, fibrogenesis, epithelial cell damage, and mechanical cell stress in this emphysema model. Wistar rats (n = 35) received repeated intratracheal instillation of porcine pancreatic elastase to induce emphysema. Seven animals were not ventilated and served as controls (NV). Twenty-eight animals were anesthetized and assigned to mechanical ventilation with a V_T CV of 0% (BASELINE). After data collection, animals (n = 7/group) were randomly allocated to V_T CVs of 0% (VV₀); 15% (VV₁₅); 22.5% (VV_22.5); or 30% (VV₃₀). In all groups, mean V_T was 6 mL/kg and positive end-expiratory pressure was 3 cmH₂O. Respiratory system mechanics and cardiac function (by echocardiography) were assessed continuously for 2 h (END). Lung histology and molecular biology were measured post-mortem. VV_22.5 and VV₃₀ decreased respiratory system elastance, while VV₁₅ had no effect. VV₀, VV₁₅, and VV_22.5, but not VV₃₀, increased pulmonary acceleration time to pulmonary ejection time ratio. VV_22.5 decreased the central moment of the mean linear intercept (D2 of Lm) while increasing the homogeneity index (1/β) compared to NV (77 ± 8 μm vs. 152 ± 45 μm; 0.85 ± 0.06 vs. 0.66 ± 0.13, p < 0.05 for both). Compared to NV, VV₃₀ was associated with higher interleukin-6 expression. Cytokine-induced neutrophil chemoattractant-1 expression was higher in all groups, except VV_22.5, compared to NV. IL-1β expression was lower in VV_22.5 and VV₃₀ compared to VV₀. IL-10 expression was higher in VV_22.5 than NV. Club cell protein 16 expression was higher in VV_22.5 than VV₀. SP-D expression was higher in VV₃₀ than NV, while SP-C was higher in VV₃₀ and VV_22.5 than VV_0. In conclusion, VV_22.5 improved respiratory system elastance and homogeneity of airspace enlargement, mitigated inflammation and epithelial cell damage, while avoiding impairment of right cardiac function in experimental elastase-induced emphysema.

Role of Streptococcus pneumoniae infection in chronic obstructive pulmonary disease patients in Italy

Background:

The aim of this study was to determine the incidence of exacerbations due to Streptococcus pneumoniae in chronic obstructive pulmonary disease (COPD) patients during stable state.

Methods:

We conducted a prospective, observational, cohort study including stable COPD patients, who were evaluated at least every 4 months over a 24-month period at the Respiratory Unit of the IRCCS Policlinico Hospital in Milan, Italy, from 2012 to 2015. Sputum samples were collected at enrollment during stable state to evaluate the frequency of S. pneumoniae colonization and in case of an acute exacerbation to evaluate the incidence of pneumococcal infection.

Results:

A total of 79 stable patients with moderate to very severe COPD were enrolled. A total of 217 samples were collected, and 27% (n = 59) of those were positive for S. pneumoniae. A total of four exacerbations due to S. pneumoniae occurred during follow up (0.31 per 100 person/month). Among positive samples of S. pneumoniae, 109 serotypes were identified. The most frequent serotypes in moderate-to-severe COPD patients during both stable state and exacerbation were 19F (12%), 18 (10%), 19A and 9V (9%) and 35 F (7%). Only 32% of COPD patients were effectively vaccinated for S. pneumoniae with PPV23 vaccine.

Conclusion:

The most frequent S. pneumoniae serotypes in COPD patients are 19F, 18, 19A, 9V and 35 F, and that almost 50% of S. pneumoniae strains could be covered by PCV13 in adult COPD patients.

Increased CTLA-4+ T cells may contribute to impaired T helper type 1 immune responses in patients with chronic obstructive pulmonary disease

Impaired T helper type 1 (Th1) function is implicated in the susceptibility of patients with chronic obstructive pulmonary disease (COPD) to respiratory infections, which are common causes of acute exacerbations of COPD (AECOPD). To understand the underlying mechanisms, we assessed regulatory T (Treg) cells and the expression of an inhibitory T-cell receptor, cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4). Cryopreserved peripheral blood mononuclear cells (PBMC) from patients with AECOPD (n = 17), patients with stable COPD (sCOPD; n = 24) and age-matched healthy non-smoking controls (n = 26) were cultured for 24 hr with brefeldin-A or monensin to detect intracellular or surface CTLA-4 (respectively) by flow cytometry. T cells in PBMC from AECOPD (n = 9), sCOPD (n = 14) and controls (n = 12) were stimulated with anti-CD3 with and without anti-CTLA-4 blocking antibodies and cytokines were quantified by ELISA. Frequencies of circulating T cells expressing intracellular CTLA-4 were higher in sCOPD (P = 0·01), whereas patients with AECOPD had more T cells expressing surface CTLA-4 than healthy controls (P = 0·03). Increased frequencies of surface CTLA-4⁺ CD4⁺ T cells and CTLA-4⁺ Treg cells paralleled increases in plasma soluble tumour necrosis factor receptor-1 levels (r = 0·32, P = 0·01 and r = 0·29, P = 0·02, respectively) in all subjects. Interferon-γ responses to anti-CD3 stimulation were inversely proportional to frequencies of CD4⁺ T cells expressing intracellular CTLA-4 (r = -0·43, P = 0·01). Moreover, CTLA-4 blockade increased the induction of interferon-γ, tumour necrosis factor-α and interleukin-6 in PBMC stimulated with anti-CD3. Overall, chronic inflammation may expand sub-populations of T cells expressing CTLA-4 in COPD patients and therefore impair T-cell function. CTLA-4 blockade may restore Th1 function in patients with COPD and so aid the clearance of bacterial pathogens responsible for AECOPD.

Precipitating causes and outcomes of chronic obstructive pulmonary disease exacerbation at a tertiary care center in northeast Thailand

Background: Acute exacerbation of chronic obstructive pulmonary disease (COPD) is a leading cause of hospitalization and economic burden. Frequent exacerbations impair quality of life and effect decline of lung function.

Objective: We evaluated characteristics of COPD patients with frequent exacerbations. The precipitating causes, outcomes, hospital stay, and cost of admission were also determined.

Methods: The study population included COPD patients admitted because of acute COPD exacerbation at Srinagarind Hospital between 1 January 2006 and 31 December 2010.

Results: Over the 5-year period, 183 patients were admitted. Their mean age was 74.9 (SD 9.28) years and the male to female ratio was 170:13. Most patients (144; 79%) had one exacerbation per year and 39 (21%) had more than one per year. The group with more exacerbations, had a higher stage of the disease than those with only one exacerbation (p = 0.023), but there was no significant difference in the mortality rate (18% vs 14%, p = 0.53). A total of 245 episodes of acute exacerbation of COPD occurred in 183 patients. The mean duration of symptoms was 4.1 (SD 3.46) days. Forty-seven percent presented with Anthonisen type III, 42.4% with Anthonisen type II, and 10.6% with Anthonisen type I exacerbations. For 44 exacerbations (18%), the precipitating causes were not determined. The most common precipitating cause was pneumonia, which occurred in 90 episodes (36.7%). The second common was bronchitis (27.8%); followed by heart failure (8.2%), infected bronchiectasis (5.3%), diarrhea (1.2%), acute urinary retention (0.8%), unstable angina (0.4%), pneumothorax (0.4%), urinary tract infection (0.4%), atrial fibrillation (0.4%) and drug induced cough (0.4%). The organisms responsible for respiratory tract infection were identified in 31% cases of pneumonia and 18% of bronchitis cases. The top three common pathogens for pneumonia were Pseudomonas aeruginosa (9%), Acinetobacter baumannii (8%), and Klebsiella pneumoniae (8%). The top three common pathogens for bronchitis were P aeruginosa (7%), Haemophilus influenza (6%), and K pneumoniae (4%). About one quarter (25.3%) of acute exacerbations were complicated by respiratory failure. The mean duration of admission was 17.3 days (range 1-682 days). The mean cost of admission per exacerbation was 80,010 Thai baht (US $2,666) (range, 2,779-3,433,108 baht). The total cost for 245 exacerbations was 19.6 million baht ($653,000).

Conclusion: Respiratory tract infections were common causes of COPD exacerbation and one quarter of which developed respiratory failure. Preventive measures such as vaccination, smoking cessation, lung rehabilitation, and appropriate drug use are helpful.

Altered Gray Matter Volume in Stable Chronic Obstructive Pulmonary Disease with Subclinical Cognitive Impairment: an Exploratory Study

Gray matter volume deficits have been identified in cognitively impaired patients with chronic obstructive pulmonary disease (COPD). However, it remains unknown whether the gray matter volume is altered in COPD patients with subclinical cognitive impairment. To determine whether any gray matter abnormalities are present in these patients, neuropsychological tests and structural MRI data were analyzed from 60 patients with COPD and 60 age-, gender-, education-, and handedness-matched normal controls (NCs). The COPD patients had similar Mini-Mental State Examination (MMSE) scores compared with the NCs. However, they had reduced Montreal Cognitive Assessment (MoCA) scores for visuospatial and executive and naming and memory functions (P < 0.001). Voxel-based morphometry (VBM) analysis revealed that the COPD patients had significantly lowered gray matter volumes in several brain regions, including the left precuneus (PrCU), bilateral calcarine (CAL), right superior temporal gyrus/middle temporal gyrus (STG/MTG), bilateral fusiform gyrus (FG), and right inferior parietal lobule (IPL) (P < 0.01, corrected). Importantly, the forced vital capacity (FVC) was found to be associated with the gray matter volume in the calcarine. The present study confirmed that brain structural changes were present in stable COPD patients with subclinical cognitive impairment. These findings may provide new insights into the pathogenesis of COPD.

Positive end expiratory pressure titration guided by plateau pressure in chronic obstructive pulmonary disease patients

BACKGROUND

PEEP decreases intrinsic PEEP (PEEPi) in COPD patients. However, the best PEEP for someone with COPD is unclear.

METHODS

Ten COPD patients who received invasive mechanical ventilation were enrolled. Before PEEP titration, subjects were sedated and received mandatory ventilation. PEEP increased from 0 to 15 cmH₂ O. At each PEEP, peak pressure (Ppeak), plateau pressure (Pplat), PEEPi, and other variables were recorded. Increment of Pplat (ΔPplat) and PEEPi were plotted against PEEP applied. The best PEEP was recorded at the cross of the two curves.

RESULTS

From PEEP = 0 cmH₂ O to best PEEP, Ppeak (37.4 ± 5.1 vs. 38.4 ± 4.9 cmH₂ O) and Pplat (18.7 ± 3.3 vs. 20.4 ± 3.2 cmH₂ O) increased slightly, resistance (28.1 ± 5.6 vs. 26.6 ± 5.0 cmH₂ O/l/s) decreased slightly, and PEEPi (7.9 ± 2.3 vs. 1.5 ± 0.4 cmH₂ O) decreased sharply. Compliance, heart rate, blood pressure, and SpO₂ did not change. However, from best PEEP to PEEP = 15 cmH₂ O, Ppeak (38.4 ± 4.9 vs. 44.9 ± 4.3 cmH₂ O) and Pplat (20.4 ± 3.2 vs. 27.6 ± 3.3 cmH₂ O) increased sharply, and systolic blood pressure (116 ± 13 vs. 99 ± 14 mmHg) and compliance (46.1 ± 18.1 vs. 37.7 ± 10.6 mL/cmH₂ O) decreased sharply. At the same time, PEEPi (1.5 ± 0.4 vs. 0.7 ± 0.8 cmH₂ O) decreased only slightly, and resistance, heart rate, and SpO₂ did not change.

CONCLUSIONS

It is feasible to use Pplat as a simple way of determining the best PEEP in COPD patients.

Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a chronic smoking-related lung disease associated with significant mortality and morbidity. It carries an enormous economic burden on the health care system. This results in a significant social impact on affected patients and their families. In this article, we review COPD in general, critical care management of patients presenting with acute exacerbation of COPD, and methods of prevention.

Comparison between Variable and Conventional Volume-Controlled Ventilation on Cardiorespiratory Parameters in Experimental Emphysema

Emphysema is characterized by loss of lung tissue elasticity and destruction of structures supporting alveoli and capillaries. The impact of mechanical ventilation strategies on ventilator-induced lung injury (VILI) in emphysema is poorly defined. New ventilator strategies should be developed to minimize VILI in emphysema. The present study was divided into two protocols: (1) characterization of an elastase-induced emphysema model in rats and identification of the time point of greatest cardiorespiratory impairment, defined as a high specific lung elastance associated with large right ventricular end-diastolic area; and (2) comparison between variable (VV) and conventional volume-controlled ventilation (VCV) on lung mechanics and morphometry, biological markers, and cardiac function at that time point. In the first protocol, Wistar rats (n = 62) received saline (SAL) or porcine pancreatic elastase (ELA) intratracheally once weekly for 4 weeks, respectively. Evaluations were performed 1, 3, 5, or 8 weeks after the last intratracheal instillation of saline or elastase. After identifying the time point of greatest cardiorespiratory impairment, an additional 32 Wistar rats were randomized into the SAL and ELA groups and then ventilated with VV or VCV (n = 8/group) [tidal volume (V_T) = 6 mL/kg, positive end-expiratory pressure (PEEP) = 3 cmH₂O, fraction of inspired oxygen (FiO₂) = 0.4] for 2 h. VV was applied on a breath-to-breath basis as a sequence of randomly generated V_T values (mean V_T = 6 mL/kg), with a 30% coefficient of variation. Non-ventilated (NV) SAL and ELA animals were used for molecular biology analysis. The time point of greatest cardiorespiratory impairment, was observed 5 weeks after the last elastase instillation. At this time point, interleukin (IL)-6, cytokine-induced neutrophil chemoattractant (CINC)-1, amphiregulin, angiopoietin (Ang)-2, and vascular endothelial growth factor (VEGF) mRNA levels were higher in ELA compared to SAL. In ELA animals, VV reduced respiratory system elastance, alveolar collapse, and hyperinflation compared to VCV, without significant differences in gas exchange, but increased right ventricular diastolic area. Interleukin-6 mRNA expression was higher in VCV and VV than NV, while surfactant protein-D was increased in VV compared to NV. In conclusion, VV improved lung function and morphology and reduced VILI, but impaired right cardiac function in this model of elastase induced-emphysema.

Nasal high flow clears anatomical dead space in upper airway models

Recent studies showed that nasal high flow (NHF) with or without supplemental oxygen can assist ventilation of patients with chronic respiratory and sleep disorders. The hypothesis of this study was to test whether NHF can clear dead space in two different models of the upper nasal airways. The first was a simple tube model consisting of a nozzle to simulate the nasal valve area, connected to a cylindrical tube to simulate the nasal cavity. The second was a more complex anatomically representative upper airway model, constructed from segmented CT-scan images of a healthy volunteer. After filling the models with tracer gases, NHF was delivered at rates of 15, 30, and 45 l/min. The tracer gas clearance was determined using dynamic infrared CO₂ spectroscopy and ^81mKr-gas radioactive gamma camera imaging. There was a similar tracer-gas clearance characteristic in the tube model and the upper airway model: clearance half-times were below 1.0 s and decreased with increasing NHF rates. For both models, the anterior compartments demonstrated faster clearance levels (half-times < 0.5 s) and the posterior sections showed slower clearance (half-times < 1.0 s). Both imaging methods showed similar flow-dependent tracer-gas clearance in the models. For the anatomically based model, there was complete tracer-gas removal from the nasal cavities within 1.0 s. The level of clearance in the nasal cavities increased by 1.8 ml/s for every 1.0 l/min increase in the rate of NHF. The study has demonstrated the fast-occurring clearance of nasal cavities by NHF therapy, which is capable of reducing of dead space rebreathing.

Interleukin-17A and Toll-Like Receptor 3 Ligand Poly(I:C) Synergistically Induced Neutrophil Chemoattractant Production by Bronchial Epithelial Cells

Chronic inflammatory airway diseases, such as bronchial asthma and chronic obstructive pulmonary disease, are common respiratory disorders worldwide. Exacerbations of these diseases are frequent and worsen patients’ respiratory condition and overall health. However, the mechanisms of exacerbation have not been fully elucidated. Recently, it was reported that interleukin (IL)-17A might play an important role in neutrophilic inflammation, which is characteristic of such exacerbations, through increased production of neutrophil chemoattractants. Therefore, we hypothesized that IL-17A was involved in the pathogenesis of acute exacerbation, due to viral infection in chronic inflammatory airway diseases. In this study, we assessed chemokine production by bronchial epithelial cells and investigated the underlying mechanisms. Comprehensive chemokine analysis showed that, compared with poly(I:C) alone, co-stimulation of BEAS-2B cells with IL-17A and poly(I:C) strongly induced production of such neutrophil chemoattractants as CXC chemokine ligand (CXCL)8, growth-related oncogene (GRO), and CXCL1. Co-stimulation synergistically induced CXCL8 and CXCL1 mRNA and protein production by BEAS-2B cells and normal human bronchial epithelial cells. Poly(I:C) induced chemokine expression by BEAS-2B cells mainly via Toll-like receptor 3/TIR-domain-containing adapter-inducing interferon-β–mediated signals. The co-stimulation with IL-17A and poly(I:C) markedly activated the p38 and extracellular-signal-regulated kinase 1/2 pathway, compared with poly(I:C), although there was little change in nuclear factor-κB translocation into the nucleus or the transcriptional activities of nuclear factor-κB and activator protein 1. IL-17A promoted stabilization of CXCL8 mRNA in BEAS-2B cells treated with poly(I:C). In conclusion, IL-17A appears to be involved in the pathogenesis of chronic inflammatory airway disease exacerbation, due to viral infection by promoting release of neutrophil chemoattractants from bronchial epithelial cells.

Wheezing, a significant clinical phenotype of COPD: experience from the Taiwan Obstructive Lung Disease Study

BACKGROUND

COPD is an important public health challenge with significant heterogeneity of clinical presentation and disease progression. Clinicians have been trying to find phenotypes that may be linked to distinct prognoses and different therapeutic choices. Not all patients with COPD present with wheezing, a possible clinical phenotype that can help differentiate patient subgroups.

METHODS

The Taiwan Obstructive Lung Disease study was a retrospective, multicenter research study to investigate the treatment patterns of COPD after the implementation of the Global Initiative for Chronic Obstructive Lung Disease 2011 guidelines. Between November 2012 and August 2013, medical records were retrieved from patients with COPD aged ≥40 years; patients diagnosed with asthma were excluded. Demographic data, lung function, symptom scores, and acute exacerbation were recorded and analyzed, and the differences between patients with and without wheezing were evaluated.

RESULTS

Of the 1,096 patients with COPD, 424 (38.7%) had the wheezing phenotype. The wheezing group had significantly higher COPD Assessment Test scores (12.4±7.8 versus 10.5±6.7, P<0.001), higher modified Medical Research Council grade (2.0±1.0 versus 1.7±0.9, P<0.001), and more acute exacerbations within the past year (0.9±1.3 versus 0.4±0.9, P<0.001) than the nonwheezing group. The postbronchodilator forced expiratory volume in 1 second was lower in wheezing patients (1.2±0.5 L versus 1.5±0.6 L, P<0.001). Even in patients with maintenance treatment fitting the Global Initiative for Chronic Obstructive Lung Disease 2011 guidelines, the wheezing group still had worse symptom scores and more exacerbations.

CONCLUSION

Wheezing is an important phenotype in patients with COPD. Patients with COPD having the wheezing phenotype are associated with worse symptoms, more exacerbations, and worse lung function.

Efficacy of a respiratory rehabilitation exercise training package in hospitalized elderly patients with acute exacerbation of COPD: a randomized control trial

Clinical trials identifier

NCT02329873

Background

Acute exacerbation (AE) of COPD is characterized by a sudden worsening of COPD symptoms. Previous studies have explored the effectiveness of respiratory rehabilitation for patients with COPD; however, no training program specific to acute exacerbation in elderly patients or unstable periods during hospitalization has been developed.

Objective

To evaluate the effects of a respiratory rehabilitation exercise training package on dyspnea, cough, exercise tolerance, and sputum expectoration among hospitalized elderly patients with AECOPD.

Methods

A randomized control trial was conducted. Pretest and posttest evaluations of 61 elderly inpatients with AECOPD (experimental group n=30; control group n=31) were performed. The experimental group received respiratory rehabilitation exercise training twice a day, 10–30 minutes per session for 4 days. The clinical parameters (dyspnea, cough, exercise tolerance, and sputum expectoration) were assessed at the baseline and at the end of the fourth day.

Results

All participants (median age =70 years, male =60.70%, and peak expiratory flow 140 L) completed the study. In the patients of the experimental group, dyspnea and cough decreased and exercise tolerance and sputum expectoration increased significantly compared with those of the patients in the control group (all P<0.05). Within-group comparisons revealed that the dyspnea, cough, and exercise tolerance significantly improved in the experimental group by the end of the fourth day (all P<0.05).

Conclusion

Results of this study suggest that the respiratory rehabilitation exercise training package reduced symptoms and enhanced the effectiveness of the care of elderly inpatients with AECOPD.

Aerobic Bacteriological Study of Acute Exacerbations of Chronic Obstructive Pulmonary Disease

BACKGROUND

The natural history of chronic obstructive pulmonary disease is characterized by frequent exacerbations. Majority of exacerbations are infectious and bacteria responsible for 30-50% of these cases. The purpose of this study was to determine the bacteriology of acute exacerbations of chronic obstructive pulmonary disease in hospitalized patients in our institution and their antibiotic susceptibility pattern to formulate cost effective antibiotic strategy and reducing the emergence of drug resistance.

MATERIALS AND METHODS

One hundred and seven clinically diagnosed cases of acute exacerbations of chronic obstructive pulmonary disease admitted in medicine, tuberculosis and chest wards were selected for the study. Direct gram stain was done for all sputum samples. The suitable sputum samples were cultured. Identification of organism and antimicrobial susceptibility testing was done by standard microbiological techniques.

RESULTS

Our study showed growth of pathogenic organisms in 41.12% cases. Males (67.29%) are more affected than females (32.71%). Gram negative bacilli were more isolated than gram positive cocci. The commonest isolate was Klebsiella pneumoniae 15 (38.46%), followed by Staphylococcus aureus 9 (23.08%), Streptococcus species 6 (15.39%), Pseudomonas aeruginosa 4 (10.26%), E.coli 2 (5.13%), Acinetobacter species 2 (5.13%) and Enterobacter species 1(2.56%). The antibiotic susceptibility reveals that vancomycin, linezolid, azithromycin and clarithromycin were most effective drugs for gram positive cocci, meropenem & piperacillin-tazobactam for gram negative bacilli and amikacin & levofloxacin for both gram positive cocci & gram negative bacilli.

CONCLUSION

In developing country like India acute exacerbations of chronic obstructive pulmonary disease is common in adults more than 50 years of age due to smoking habits and high indoor pollution. This leads to a major impact on the quality of life of patients with the condition. They are a major cause of hospital admission and health care utilization.

Severe hypoalbuminemia is a strong independent risk factor for acute respiratory failure in COPD: a nationwide cohort study

Background

Acute respiratory failure (ARF) is a life-threatening event, which is frequently associated with the severe exacerbations of chronic obstructive pulmonary disease (COPD). Hypoalbuminemia is associated with increased mortality in patients with COPD. However, to date, little is known regarding whether or not hypoalbuminemia is a risk factor for developing ARF in COPD.

Methods

We conducted a retrospective cohort study using data from the National Health Insurance system of Taiwan. A total of 42,732 newly diagnosed COPD patients (age ≥40 years) from 1997 to 2011 were enrolled. Among them, 1,861 (4.36%) patients who had received albumin supplementation were defined as hypoalbuminemia, and 40,871 (95.6%) patients who had not received albumin supplementation were defined as no hypoalbuminemia.

Results

Of 42,732 newly diagnosed COPD patients, 5,248 patients (12.3%) developed ARF during the 6 years follow-up period. Patients with hypoalbuminemia were older, predominantly male, had more comorbidities, and required more steroid treatment and blood transfusions than patients without hypoalbuminemia. In a multivariable Cox regression analysis model, being elderly was the strongest independent risk factor for ARF (adjusted hazard ratio [HR]: 4.63, P<0.001), followed by hypoalbuminemia (adjusted HR: 2.87, P<0.001). However, as the annual average dose of albumin supplementation was higher than 13.8 g per year, the risk for ARF was the highest (adjusted HR: 11.13, 95% CI: 10.35–11.98, P<0.001).

Conclusion

Hypoalbuminemia is a strong risk factor for ARF in patients with COPD. Therefore, further prospective studies are required to verify whether or not albumin supplementation or nutritional support may help to reduce the risk of ARF in patients with COPD.

Hospital management of acute exacerbations of chronic obstructive pulmonary disease

The course of chronic obstructive pulmonary disease (COPD) is often complicated by episodes of acute worsening of respiratory symptoms, which may lead to escalation of therapy and occasionally emergency department visits and hospitalization. Acute exacerbations of COPD (AECOPD) have a negative impact on quality of life and hasten the decline of lung function. They also significantly contribute to the direct and indirect healthcare costs of this disease. Severe exacerbations (those leading to hospital admission) have been associated with significant poor outcomes including an increased risk of readmissions and mortality. COPD is currently the fourth leading cause of hospital readmission in the United States. In this review, we will provide a broad overview on the etiology, assessment, management, discharge planning, and follow-up care of patients hospitalized with AECOPD.

Novosphingobium and its potential role in chronic obstructive pulmonary diseases: insights from microbiome studies

Bacterial infection of lung airways underlies some of the main complications of COPD, significantly impacting disease progression and outcome. Colonization by bacteria may further synergize, amplify, or trigger pathways of tissue damage started by cigarette smoke, contributing to the characteristic airway inflammation and alveolar destruction of COPD. We sought to elucidate the presence and types of lung bacterial populations in different stages of COPD, aimed at revealing important insights into the pathobiology of the disease. Sequencing of the bacterial small subunit ribosomal RNA gene in 55 well-characterized clinical lung samples, revealed the presence of Novosphingobium spp. (>2% abundance) in lungs of patients with GOLD 3-GOLD 4 COPD, cystic fibrosis and a subset of control individuals. Novosphingobium-specific quantitative PCR was concordant with the sequence data and high levels of Novosphingobium spp. were quantifiable in advanced COPD, but not from other disease stages. Using a mouse model of subacute lung injury due to inhalation of cigarette smoke, bronchoalveolar lavage neutrophil and macrophage counts were significantly higher in mice challenged intratracheally with N. panipatense compared to control mice (p<0.01). Frequencies of neutrophils and macrophages in lung tissue were increased in mice challenged with N. panipatense at room air compared to controls. However, we did not observe an interaction between N. panipatense and subacute cigarette smoke exposure in the mouse. In conclusion, Novosphingobium spp. are present in more severe COPD disease, and increase inflammation in a mouse model of smoke exposure.

Understanding patients' and doctors' attitudes about shared decision making for advance care planning

Background

Although shared decision making (SDM) is the preferred model of making complex treatment decisions with patients, patients' and doctors' attitudes towards SDM for advance care planning are unknown.

Objective

We sought to: (i) gain general insights into the current practice of SDM and attitudes about patient involvement, and (ii) gain specific insights into experience with, and attitudes about, SDM for advance care planning.

Design

Qualitative analysis of face‐to‐face semi‐structured interviews.

Setting and participants

Patients with chronic lung disease and their doctors at a New York City public hospital.

Results

Although patients described participation in decision making, many deferred the final decision to their doctors. Doctors indicated a preference for SDM but expressed barriers including perceived lack of patient understanding and lack of patient empowerment. With regard to end‐of‐life discussions, patients were generally open to having these discussions with their doctors, although their openness sometimes depended on the circumstance (i.e. end‐of‐life discussions may be more acceptable to patients for whom the chance of dying is high). Doctors reported engaging in end‐of‐life treatment decisions with their patients, although expressed the need for conversations to take place earlier, in advance of acute illness, and identified a lack of prognostic estimates as one barrier to engaging in this discussion.

Conclusions

Doctors should explore their patients' attitudes regarding end‐of‐life discussions and preferences for decision‐making styles. There is a need for tools such as decision aids which can empower patients to participate in decision making and can support doctors with prognostic estimates pertinent to individual patients.

Dynamics of inflammation resolution and symptom recovery during AECOPD treatment

The association between increases in both systemic and airway inflammation and acute exacerbation of COPD (AECOPD) has been reported by many studies. However, relatively little is known about the dynamics of inflammation resolution and their correlations with the improvement of clinical indices during treatment. In this study, a total of 93 consecutively hospitalized patients with AECOPD were recruited. Sputum and serum inflammatory markers were measured on the day of admission before treatment (day 0), day 4, 7 and 14 during treatment as well as 8 weeks after discharge. Clinical indices (lung function, dyspnea and COPD assessment test (CAT) scores) were also measured at those time points. By day 4, all airway inflammatory measures rapidly decreased and returned to baseline level. Notably, lung function and dyspnea improved to the baseline level by day 4 as well, consistent with the resolution of respiratory inflammation. However, despite the significant decrease by day 4, systemic inflammation did not reach baseline until day 14, concordant with the decrease in CAT score. In summary, we observed a time lag between the resolution of systemic and airway inflammation, which were correlated with the improvements of different clinical indices.

Emerging indications for extracorporeal membrane oxygenation in adults with respiratory failure

Recent advances in technology have spurred the increasing use of extracorporeal membrane oxygenation (ECMO) in patients with severe hypoxemic respiratory failure. However, this accounts for only a small percentage of patients with respiratory failure. We envision the application of ECMO in many other forms of respiratory failure in the coming years. Patients with less severe forms of acute respiratory distress syndrome, for instance, may benefit from enhanced lung-protective ventilation with the very low tidal volumes made possible by direct carbon dioxide removal from the blood. For those in whom hypercapnia predominates, extracorporeal support will allow for the elimination of invasive mechanical ventilation in some cases. The potential benefits of ECMO may be further enhanced by improved techniques, which facilitate active mobilization. Although ECMO for these and other expanded applications is under active investigation, it has yet to be proven beneficial in these settings in rigorous controlled trials. Ultimately, with upcoming and future technological advances, there is the promise of true destination therapy, which could lead to a major paradigm shift in the management of respiratory failure.

Hypercapnia impairs lung neutrophil function and increases mortality in murine pseudomonas pneumonia

Hypercapnia, an elevation of the level of carbon dioxide (CO2) in blood and tissues, is a marker of poor prognosis in chronic obstructive pulmonary disease and other pulmonary disorders. We previously reported that hypercapnia inhibits the expression of TNF and IL-6 and phagocytosis in macrophages in vitro. In the present study, we determined the effects of normoxic hypercapnia (10% CO2, 21% O2, and 69% N2) on outcomes of Pseudomonas aeruginosa pneumonia in BALB/c mice and on pulmonary neutrophil function. We found that the mortality of P. aeruginosa pneumonia was increased in 10% CO2-exposed compared with air-exposed mice. Hypercapnia increased pneumonia mortality similarly in mice with acute and chronic respiratory acidosis, indicating an effect unrelated to the degree of acidosis. Exposure to 10% CO2 increased the burden of P. aeruginosa in the lungs, spleen, and liver, but did not alter lung injury attributable to pneumonia. Hypercapnia did not reduce pulmonary neutrophil recruitment during infection, but alveolar neutrophils from 10% CO2-exposed mice phagocytosed fewer bacteria and produced less H2O2 than neutrophils from air-exposed mice. Secretion of IL-6 and TNF in the lungs of 10% CO2-exposed mice was decreased 7 hours, but not 15 hours, after the onset of pneumonia, indicating that hypercapnia inhibited the early cytokine response to infection. The increase in pneumonia mortality caused by elevated CO2 was reversible when hypercapnic mice were returned to breathing air before or immediately after infection. These results suggest that hypercapnia may increase the susceptibility to and/or worsen the outcome of lung infections in patients with severe lung disease.

Predicting chronic obstructive pulmonary disease hospitalizations based on concurrent influenza activity

Although influenza has been associated with chronic obstructive pulmonary disease (COPD) exacerbations, it is not clear the extent to which this association affects healthcare use in the United States. The first goal of this project was to determine to what extent the incidence of COPD hospitalizations is associated with seasonal influenza. Second, as a natural experiment, we used influenza activity to help predict COPD admissions during the 2009 H1N1 influenza pandemic. To do this, we identified all hospitalizations between 1998 and 2010 in the Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project (HCUP) during which a primary diagnosis of COPD was recorded. Separately, we identified all hospitalizations during which a diagnosis of influenza was recorded. We formulated time series regression models to investigate the association of monthly COPD admissions with influenza incidence. Finally, we applied these models, fit using 1998-2008 data, to forecast monthly COPD admissions during the 2009 pandemic. Based on time series regression models, a strong, significant association exists between concurrent influenza activity and incidence of COPD hospitalizations (p-value < 0.0001). The association is especially strong among older patients requiring mechanical ventilation. Use of influenza data to predict COPD admissions during the 2009 H1N1 pandemic reduced the mean-squared prediction error by 29.9%. We conclude that influenza activity is significantly associated with COPD hospitalizations in the United States and influenza activity can be exploited to more accurately forecast COPD admissions. Our results suggest that improvements in influenza surveillance, prevention, and treatment may decrease hospitalizations of patients diagnosed with COPD.

Removing extra CO2 in COPD patients

For patients experiencing acute respiratory failure due to a severe exacerbation of chronic obstructive pulmonary disease (COPD), noninvasive positive pressure ventilation has been shown to significantly reduce mortality and hospital length of stay compared to respiratory support with invasive mechanical ventilation. Despite continued improvements in the administration of noninvasive ventilation (NIV), refractory hypercapnia and hypercapnic acidosis continue to prevent its successful use in many patients. Recent advances in extracorporeal gas exchange technology have led to the development of systems designed to be safer and simpler by focusing on the clinical benefits of partial extracorporeal carbon dioxide removal (ECCO2R), as opposed to full cardiopulmonary support. While the use of ECCO2R has been studied in the treatment of acute respiratory distress syndrome (ARDS), its use for acute hypercapnic respiratory during COPD exacerbations has not been evaluated until recently. This review will focus on literature published over the last year on the use of ECCO2R for removing extra CO2 in patients experiencing an acute exacerbation of COPD.

Association between Severity of Chronic Obstructive Pulmonary Disease and Lung Function Tests

BACKGROUND

The burden of chronic obstructive pulmonary disease (COPD) is quite high and its prevalence is increasing. We aimed to evaluate the correlation of COPD severity according to the American Thoracic Society (ATS) criteria with spirometric measurements in patients admitted to the emergency ward.

MATERIALS AND METHODS

In this cross-sectional descriptive study, 50 randomly selected patients with COPD admitted to the emergency ward in a tertiary care center were evaluated. The COPD severity according to the ATS criteria was measured and its association with spirometric findings was evaluated. The statistical analysis was performed by SPSS software and the Kendall's tau-b correlation test.

RESULTS

The mean age (±standard deviation) was 64.3 ± 11.3 years. Twelve percent were females and 88 percent were males. The COPD severity, according to the ATS criteria, was mild in 16%, moderate in 48%, severe in 32% and very severe in four percent. There was a statistically significant correlation between total lung capacity (TLC) and COPD severity (P = 0.013, r = 275). Besides, there was a statistically significant correlation between functional residual capacity (FRC) and COPD severity (P = 0.022, r = 255). Age, sex, and the other spirometric findings especially FEV1 and FVC had no association with COPD severity (P > 0.05).

CONCLUSION

According to the obtained results, it is concluded that determining the COPD severity according to the ATS criteria may help the physicians to estimate the patients' prognosis and therapeutic planning. However, the spirometric measurements may not be replaced by ATS criteria.

Arrhythmias as trigger for acute exacerbations of chronic obstructive pulmonary disease

PURPOSE

Acute exacerbations of chronic obstructive pulmonary disease (COPD) sometimes appear to occur without a precipitating cause. Heterogeneous repolarization and arrhythmias occur in COPD patients. Given the close inter-relation between heart and lung, we hypothesized that unrecognized arrhythmias might be precipitants of acute exacerbations.

METHODS

Electrocardiograms (ECG) of thirty patients during acute exacerbations were compared with ECG during stable phase. P wave dispersion was used to assess atrial depolarization heterogeneity, and dispersion of QT interval to assess ventricular repolarization. p < 0.05 was considered significant. Frequent exacerbations were defined as two or more exacerbations in a year.

RESULTS

Mean age of patients was 70.3 ± 11.8 SD years. P wave dispersion was greater during acute exacerbation than during stable phase (56.7 ± 19.2 vs 47.7 ± 15.9 ms, p = 0.009). There was a trend toward greater QTc dispersion (108.3 ± 61.7 vs 90.3 ± 47.0 ms, p = 0.13) in acute exacerbation compared to stable phase. Sixteen (53%) had frequent exacerbations. There was a significant difference in PR interval during stable phase between those with frequent exacerbations and those without (163.9 + 17.4 vs. 145.1 + 22.8; p = 0.02). The P wave dispersion during stable phase was greater in those with frequent exacerbations, but did not reach statistical significance (52.6 + 18.8 vs. 42.2 + 9.8 ms; p = 0.06).

CONCLUSIONS

P wave dispersion is more in the acute phase than in stable phase, and is greater in patients with more frequent exacerbations. This does not prove, but suggests an intriguing possibility that P wave dispersion predates acute exacerbations. This might be a new target for prediction, prevention and therapy of acute exacerbations of COPD.

Are we aware of restless legs syndrome in COPD patients who are in an exacerbation period? Frequency and probable factors related to underlying mechanism

A few previous studies have reported that the patients with chronic obstructive pulmonary disease (COPD) have a 29.1% to 36.8% frequency of restless legs syndrome (RLS). In this study, we observed RLS symptoms in patients experiencing COPD exacerbation to better understand the relationship between the many clinical parameters of COPD and the presence of RLS and to attract the attention of specialists on the association between the two conditions. Twenty-two male patients in COPD exacerbation; 17 healthy individuals were evaluated in this study. The patients were evaluated using the 2003 RLS symptom criteria outlined by the International Restless Legs Syndrome Study Groups (IRLSSG). The Pittsburgh Sleep Quality Index and Epworth daytime sleepiness scale were used to assess the sleep quality of patients. The RLS symptoms were correlated with blood levels of laboratory and clinical parameters. Statistical analyses were performed using SPSS 17.0 statistical software packet. The Pittsburgh Sleep Quality Index and Epworth daytime sleepiness scale scores were increased in COPD patients and correlated significantly with RLS symptoms. It was found that 54.5% of COPD patients with acute exacerbations were observed to have RLS symptoms. The Pittsburgh Sleep Quality Index was significantly higher in COPD patients with RLS symptoms compared to COPD patients without RLS symptoms (p < 0.05). We did not observe any significant difference in the previously reported metabolic and clinical parameters associated with RLS in COPD patients with and without RLS. RLS symptoms increase during COPD exacerbation and lead to decreased sleep quality.

Characteristics of COPD patients admitted to the ICU of a referral hospital for respiratory diseases in Brazil

OBJECTIVE

To report data regarding COPD patients admitted to the ICU of a referral hospital for respiratory diseases, including outcomes and treatment evaluation.

METHODS

Study of a series of patients with respiratory failure and COPD admitted to the ICU of Nereu Ramos Hospital, located in the city of Florianópolis, Brazil, between October of 2006 and October of 2007. Data related to demographics, causes of hospitalization, pharmacological treatment, ventilatory support, length of hospital stay, in-hospital complications, ICU mortality, and 28-day mortality were obtained from the medical charts of the patients. Acute Physiology and Chronic Health Evaluation II (APACHE II) scores were calculated. Mortality at 18 months was assessed by subsequent telephone calls.

RESULTS

During the study period, 192 patients were admitted to the ICU, 24 (12.5%) of whom were diagnosed with respiratory failure and COPD. The mean length of ICU stay was 12.0 ± 11.1 days. Noninvasive ventilation was used in 10 of the 24 patients (41.66%) and failed in 5 of those 10. Invasive mechanical ventilation (IMV) was used in a total of 15 patients (62.5%). Overall ICU mortality and 28-day mortality were 20.83% and 33.33%, respectively. However, 18-month mortality was 62.5%.

CONCLUSIONS

Respiratory failure associated with COPD was responsible for 12.5% of the ICU admissions. Orotracheal intubation and IMV were necessary in 62.5% of the cases. The ICU mortality rate was in accordance with that predicted by the APACHE II scores. However, late mortality was high.

Polyvalent mechanical bacterial lysate for the prevention of recurrent respiratory infections: a meta-analysis

BACKGROUND

Respiratory tract infections are common and remain a major source of morbidity, mortality and economic cost worldwide, despite advances in modern medicine. One treatment approach is to non-specifically increase the immune response or augment innate defense mechanisms through the use of bacterial lysates. Polyvalent Mechanical Bacterial Lysate (PMBL) is a bacterial lysate made from a wide range of pathogenic bacteria, including all of the most commonly occurring pathogens of the upper and lower respiratory tract obtained by mechanical lysis.

AIM

To test the available evidence that PMBL is able to prevent respiratory tract infections.

METHODS

A number of studies investigating randomized comparisons of PMBL (active) with placebo or no treatment (control) were selected for analysis. The primary outcome measure was the prevention of exacerbations or acute respiratory tract infection. The results were expressed as relative risk (RR) and the number of patients needed to treat for one to benefit (NNTB).

RESULTS

Data from 2557 patients from 15 randomized clinical trials (RCTs) was investigated. PMBL induced a significant reduction of infections vs placebo (RR -0.513; 95% CI; -0.722 - -0.303; p = 0.00). The NNTB was 1.15. The RR was always in favor of PMBL (in recurrent respiratory infections other than COPD, chronic bronchitis and tuberculosis, RR -0.502; 95% CI -0.824 - -0.181; in children RR -2.204; 95% CI -3.260 - -1.147; in COPD or chronic bronchitis, RR -0.404; 95% CI -0.864-0.057; in tuberculosis, RR -0.502; 95% CI -0.890 - -0.114).

CONCLUSIONS

The results of the present meta-analysis suggest that PBML is effective in both in children and in adults in preventing respiratory tract infections. Our current meta-analysis shows that there is a trend with PBML toward clinically significant results in patients with COPD but it did not quite achieve statistical significance due to the small number of COPD studies.

Acute lung failure

Lung failure is the most common organ failure seen in the intensive care unit. The pathogenesis of acute respiratory failure (ARF) can be classified as (1) neuromuscular in origin, (2) secondary to acute and chronic obstructive airway diseases, (3) alveolar processes such as cardiogenic and noncardiogenic pulmonary edema and pneumonia, and (4) vascular diseases such as acute or chronic pulmonary embolism. This article reviews the more common causes of ARF from each group, including the pathological mechanisms and the principles of critical care management, focusing on the supportive, specific, and adjunctive therapies for each condition.

Antibiotic therapy for exacerbations of chronic obstructive pulmonary disease (COPD)

Chronic obstructive pulmonary disease (COPD) is already the world's fourth most common cause of mortality and likely to become the third in a few year's time. Because it is an inflammatory airway disease with altered host immune response, infectious complications are frequent. Acute exacerbations of COPD (AECOPD) significantly worsen the patient's general health, accelerating disability. Each exacerbation leads progressively to further deterioration of lung function. Among the various causes of AECOPD, including viruses, bacteria and air pollution, a bacterial etiology is most common (50-69%). The management of AECOPD remains extremely challenging and places a heavy economic burden on health care institutions. The decision to administer antibiotics in AECOPD is multifactorial, the most important considerations being severity of the COPD stage and patient performance status, clinical symptoms (increased dyspnea, sputum volume and sputum purulence), severity of current and previous exacerbations, comorbidity and current smoking. Exacerbations which require hospital admission are associated with significant in-patient mortality. AECOPD patients presenting with worsening dyspnea, increased sputum volume and purulence should be offered antimicrobial therapy. If treating with antibiotics, treatment must include coverage for Haemophilus influenzae, Streptococcus pneumoniae and Moraxella catarrhalis in all cases, but other bacteria (such as Gram-negatives) may need to be covered depending on the condition of the patient. Antibiotics, particularly macrolides and fluoroquinolones, when administered under suitable conditions, shorten the clinical course and prevent severe deterioration. possible complications resulting from untreated severe AECOPD surpass the potential risks from the use of antibiotic therapy. Additional anti-inflammatory and immunomodulatory actions of some antibiotics may contribute to their efficacy in AECOPD.

The effects of ‘on-call/out of hours’ physical therapy in acute exacerbations of chronic obstructive pulmonary disease: a randomized controlled trial

Objective: To assess the effectiveness of an on-call physical therapy programme in the management of acute exacerbations of chronic obstructive pulmonary diseases.

Design: Randomized controlled trial.

Setting: Secondary care level, rural hospital.

Subjects: Thirty-eight patients with acute exacerbations of chronic obstructive pulmonary disease.

Interventions: Regular physical therapy and on-call physical therapy was given to two groups of patients with 19 in each arm. On-call physical therapy included providing respiratory physical therapy as required by the patient out of business hours.

Main measures: Peak expiratory flow rate, sustained maximal inspiration, six-minute walk distance and rating of perceived exertion post six-minute walk test.

Results: In the group receiving on-call physical therapy, peak expiratory flow rate and six-minute walk test showed a significant difference (52.1 L/min and 98.16 m, respectively) when compared with the control group (211.57 ± 51.12 L/min and 159.47 ± 67.78 L/min; P =0.01 and 387.89 ± 110.1 m and 289.73 ± 103.2 m; P=0.004 respectively). The difference in peak expiratory flow rate (Δ peak expiratory flow rate) was seen to be more in the on-call group (120 L/min) when compared to the control group (50 L/min), P =0.002. Improvements in sustained maximal inspiration and Borg’s rating of perceived exertion after the six-minute walk test were also observed (P>0.05).

Conclusion: On-call physical therapy brings about a significant increase in peak expiratory flow rates, six-minute walk distance and sustained maximal inspiration.

Treatment of acute bacterial exacerbations of chronic bronchitis

BACKGROUND

Controversies persist regarding the optimal management of patients with acute exacerbations of chronic bronchitis (AECB).

OBJECTIVE

To evaluate the available evidence on relevant issues, namely the need for administering antimicrobials in patients with AECB, the identification of the subgroup of patients with AECB needing antibiotics, the antimicrobial regimen of choice and its optimal duration, the existence of new agents, and the value of non-antimicrobial regimens for AECB.

METHODS

Data from various sources of evidence, including recent relevant meta-analyses, were appraised.

CONCLUSION

Administration of antimicrobial agents, combined with bronchodilators and systemic corticosteroids, is warranted in approximately half of AECBs (i.e., in bacterial exacerbations) to achieve a survival benefit. Simple clinical parameters, mainly sputum purulence, and biomarkers, such as procalcitonin, are useful in identifying patients requiring antibiotics. Advanced antibiotics (quinolones, macrolides, or amoxicillin/clavulanic acid) are more effective than 'old' antibiotics in AECB; regimens of short duration (for 5 days) are preferred. There is no difference between several classes of advanced antibiotics regarding their short-term effectiveness; however, quinolones are associated with better long-term outcomes than macrolides. Newer quinolones and new formulations of macrolides enrich clinicians' armamentarium against AECB.

Treatment of respiratory failure in COPD

Patients with advanced COPD and acute or chronic respiratory failure are at high risk for death. Beyond pharmacological treatment, supplemental oxygen and mechanical ventilation are major treatment options. This review describes the physiological concepts underlying respiratory failure and its therapy, as well as important treatment outcomes. The rationale for the controlled supply of oxygen in acute hypoxic respiratory failure is undisputed. There is also a clear survival benefit from long-term oxygen therapy in patients with chronic hypoxia, while in mild, nocturnal, or exercise-induced hypoxemia such long-term benefits appear questionable. Furthermore, much evidence supports the use of non-invasive positive pressure ventilation in acute hypercapnic respiratory failure. It application reduces intubation and mortality rates, and the duration of intensive care unit or hospital stays, particularly in the presence of mild to moderate respiratory acidosis. COPD with chronic hypercapnic respiratory failure became a major indication for domiciliary mechanical ventilation, based on pathophysiological reasoning and on data regarding symptoms and quality of life. Still, however, its relevance for long-term survival has to be substantiated in prospective controlled studies. Such studies might preferentially recruit patients with repeated hypercapnic decompensation or a high risk for death, while ensuring effective ventilation and the patients’ adherence to therapy.

Healthcare costs associated with initial maintenance therapy with fluticasone propionate 250 μg/salmeterol 50 μg combination versus anticholinergic bronchodilators in elderly US Medicare-eligible beneficiaries with COPD

OBJECTIVE

To compare, in elderly Medicare beneficiaries, chronic obstructive pulmonary disease (COPD)-related healthcare costs for patients initiating treatment with fluticasone propionate/salmeterol 250 μg/50 μg (FSC) with those for patients initiating treatment with ipratropium bromide/albuterol (IPA), ipratropium bromide (IPR), and tiotropium bromide (TIO).

METHODS

In this retrospective, observational, cohort study, COPD-related medical costs (inpatient/emergency department, outpatient) and pharmacy costs were assessed in Medicare beneficiaries ≥ 65 years old who were enrolled in a commercial Medicare health maintenance organization plan and had a diagnosis of COPD (ICD-9-CM codes 491.xx, 492.xx, or 496.xx) within 12 months before initial treatment with FSC, IPA, IPR, or TIO.

RESULTS

In these ≥ 65-year-old patients (N=14,689), initial maintenance treatment with FSC was associated with total COPD-related cost savings (medical + pharmacy) of $295 versus IPA, $1,235 versus IPR, and $110 versus TIO (p<0.05, each comparison) over a 1-year follow-up period.

CONCLUSIONS

Initiation of maintenance therapy with FSC was associated with significant reduction in total costs (medical + pharmacy) relative to costs associated with the short-acting anticholinergic bronchodilators IPR and IPA and the long-acting anticholinergic bronchodilator TIO in an elderly Medicare-eligible population. These data considered in the context of the substantial efficacy and effectiveness data suggest that early introduction of maintenance treatment with FSC has both clinical and economic benefits. Limitations inherent in handling of administrative data include lack of objective clinical measures such as spirometry and smoking status. Furthermore, accuracy of diagnosis codes cannot be verified.