Occlusion pressure and breathing pattern in children with chronic obstructive pulmonary disease

The control of breathing at rest was studied in 30 children (3 to 17 years old) with chronic obstructive pulmonary disease (COPD). Five of them were tested several times during the follow-up of the COPD. Breathing pattern was evaluated and mouth occlusion pressure (PO.1) was measured. Results in COPD children were compared to previously reported values in healthy controls. PO.1 was significantly increased. In 11 children breathing O2, PO.1 decreased but remained at higher levels than predicted. However, the decrease in PO.1 in COPD was not significantly greater than in healthy children. These results may be explained by the relative mild hypoxemia in those children. The increase in PO.1 was significantly correlated with the increase in lung resistance (p less than 0.02) and with the decrease in dynamic lung compliance (p less than 0.01). Most of the COPD children were normocapnic. However, modifications in the breathing pattern were observed. The inspiratory time (TI) was significantly shortened, the expiratory time was prolonged and the TI over the total duration of the respiratory cycle was lowered. The respiratory frequency was unchanged. The tidal volume, normalized for body weight (VTBW), was increased. The mean inspiratory flow (VTBW/TI) was significantly augmented, but not as much as PO.1: in consequence, the effective inspiratory impedance was higher than predicted. Thus, as adults, COPD children had a greater inspiratory neural drive. In contrast to normocapnic COPD adults, they had a modified respiratory timing.     

Arousal thresholds during human tonic and phasic REM sleep

The goal of the present study was to investigate arousal thresholds (ATs) in tonic and phasic episodes of rapid eye movement (REM) sleep, and to compare the frequency spectrum of these sub‐states of REM to non‐REM (NREM) stages of sleep. We found the two REM stages to differ with regard to behavioural responses to external acoustic stimuli. The AT in tonic REM was indifferent from that in sleep stage 2, and ATs in phasic REM were similar to those in slow‐wave sleep (stage 4). NREM and REM stages of similar behavioural thresholds were distinctly different with regard to their frequency pattern. These data provide further evidence that REM sleep should not be regarded a uniform state. Regarding electroencephalogram frequency spectra, we found that the two REM stages were more similar to each other than to NREM stages with similar responsivity. Ocular activity such as ponto‐geniculo‐occipital‐like waves and microsaccades are discussed as likely modulators of behavioural responsiveness and cortical processing of auditory information in the two REM sub‐states.     

Host-pathogen interaction during pneumococcal infection in patients with chronic obstructive pulmonary disease

Acute exacerbation is a frequent complication of chronic obstructive pulmonary disease (COPD). Recent studies suggested a role for bacteria such as Streptococcus pneumoniae in the development of acute exacerbation. For this study, we investigated the following in COPD patients: (i) the epidemiology of pneumococcal colonization and infection, (ii) the effect of pneumococcal colonization on the development of exacerbation, and (iii) the immunological response against S. pneumoniae. We cultured sputa of 269 COPD patients during a stable state and during exacerbation of COPD and characterized 115 pneumococcal isolates by use of serotyping. Moreover, we studied serum immunoglobulin G (IgG) antibody titers, antibody avidities, and functional antibody titers against the seven conjugate vaccine serotypes in these patients. Colonization with only pneumococci (monocultures) increased the risk of exacerbation, with a hazard ratio of 2.93 (95% confidence interval, 1.41 to 6.07). The most prevalent pneumococcal serotypes found were serotypes 19F, 3, 14, 9L/N/V, 23A/B, and 11. We calculated the theoretical coverage for the 7- and 11-valent pneumococcal vaccines to be 60 and 73%, respectively. All patients had detectable IgG levels against the seven conjugate vaccine serotypes. These antibody titers were significantly lower than those in vaccinated healthy adults. Finally, on average, a 2.5-fold rise in serotype-specific and functional antibodies in S. pneumoniae-positive sputum cultures was observed during exacerbation. Our data indicate that pneumococcal colonization in COPD patients is frequently caused by vaccine serotype strains. Moreover, pneumococcal colonization is a risk factor for exacerbation of COPD. Finally, our findings demonstrate that COPD patients are able to mount a significant immune response to pneumococcal infection. COPD patients may therefore benefit from pneumococcal vaccination.     

Different pattern of viral infections and clinical outcomes in patient with acute exacerbation of chronic obstructive pulmonary disease and chronic obstructive pulmonary disease with pneumonia

Respiratory viruses are well‐known causes of acute exacerbation of chronic obstructive pulmonary disease (AE‐COPD) and also important pathogens for concomitant pneumonia in COPD (CP‐COPD). However, the differences in a viral infection pattern and clinical impacts of respiratory viruses between the two groups have not been well investigated. The clinical and microbiological data from COPD patients admitted with AE‐COPD (n = 281) or CP‐COPD (n = 284) between January 2010 and December 2012 were reviewed. After excluding 88 patients (40 with AE‐COPD and 48 with CP‐COPD) who did not undergo a multiplex RT‐PCR test for respiratory viruses, the demographic characteristics, identified viruses, and clinical outcomes of the AE‐COPD and CP‐COPD groups were compared. Respiratory viruses were identified in 41.9% of AE‐COPD group and 33.5% of the CP‐COPD groups. The most common virus was influenza virus in the AE‐COPD group (33.7%) versus human coronavirus (24.1%) in the CP‐COPD group. Influenza virus was significantly more common in the AE‐ACOPD group than in the CP‐COPD group (P < 0.01). In‐hospital mortality of AE‐COPD and CP‐COPD were 1.2% and 12.3%, respectively (P < 0.01). Among CP‐COPD patients, in‐hospital mortality of patients with only viral infection group, only bacterial infection group, and viral‐bacterial co‐infection were 2.6%, 25.8%, and 17.5%, respectively (P = 0.01). Respiratory viruses were commonly identified in both AE‐COPD and CP‐COPD, influenza virus and human coronavirus were the most common viruses identified in AE‐COPD and CP‐COPD patients, respectively. The mortality rates of only viral infection group was significantly lower than only bacterial infection or viral‐bacterial co‐infection group in CP‐COPD patients. J. Med. Virol. 88:2092–2099, 2016. © 2016 Wiley Periodicals, Inc.

     

Systemic oxygen extraction during incremental exercise in patients with severe chronic obstructive pulmonary disease

To determine if decreased systemic oxygen (O₂) extraction contributes to the exercise limit in severe chronic obstructive pulmonary disease (COPD), 40 consecutive incremental cycle ergometer exercise tests performed by such patients, from which a “log-log” lactate threshold (LT) was identified, were compared to those of 8 patients with left ventricular failure (LVF) and 10 normal controls. Pulmonary gas exchange and minute ventilation were measured continuously and arterial blood gas tensions, pH, and lactate concentrations were sampled each minute. Cardiac output (Q˙ _c) was measured by first-pass radionuclide ventriculography. The systemic O₂ extraction ratio (O₂ER) was calculated as arterial − mixed venous O₂ content difference (C _aO₂ − C _vO₂)/C _aO₂. Peak exercise O₂ uptake (V˙O_2peak) was markedly reduced in both COPD and LVF [41 (3) and 42 (3)% predicted, respectively], compared to controls [89 (2)% predicted, P < 0.0001 for each]. Similarly, the LT occurred at a low percentage of predicted maximal oxygen consumption in both COPD and LVF [25 (2) and 27 (3)%] compared to normals [46 (3)%, P < 0.0001 for each]. The systemic O₂ER at peak exercise was severely reduced in COPD [0.36 (0.02)] compared to the other groups [P < 0.0001 for each], for whom it was nearly identical [0.58 (0.03) vs 0.63 (0.04), LVF vs control, P > 0.05]. In the COPD group, an early LT correlated with reduced systemic O₂ER at peak exercise (r = 0.64, P < 0.0001), but not with any index of systemic O₂ delivery. These data suggest that lactic acidemia during exercise in patients with severe COPD is better related to abnormal systemic O₂ extraction than to its delivery and contributes to the exercise limit. Accepted: 10 March 1998     

Neuromuscular transmission in hypoxemic patients with chronic obstructive pulmonary disease

Many studies have focused on the systemic effects of chronic obstructive pulmonary disease (COPD), but none has examined neuromuscular junction transmission (NMT). We evaluated NMT dysfunction using single-fiber electromyography (SFEMG) in patients with COPD. Twenty patients with COPD and 20 age-matched healthy controls were included in the study. All patients and controls underwent SFEMG. Abnormal NMT was found in seven of 20 patients (35%), but in none of the control subjects. The COPD patients were subgrouped according to the presence of hypoxemia. The patients with normoxemia were classified as Group 1, and the patients with hypoxemia were classified as Group 2. Abnormal NMT was found in six patients in Group 2 and in one in Group 1. While there was significant difference in terms of abnormal NMT between Group 2 and the controls, there was none between Group 1 and the controls. Our results show that NMT abnormalities can be present in hypoxemic patients with COPD.     

Right ventricular function in patients with chronic obstructive pulmonary disease

Summary Simultaneous right heart catheterization and radionuclide ventriculography were performed in 27 patients with a wide range of chronic obstructive pulmonary disease. Central hemodynamics and radionuclide studies were done at rest and during exercise. In the resting state the right ventricular ejection fraction (RVEF) was in the normal range (43.3±6%). During exercise a significant (p<0.001) decrease of RVEF to 38.8±6.7% occurred. The pumonary artery mean pressures were 19.9±3.8 at rest. During exercise a significant (p<0.001) increase to 41±9.8 mm Hg occurred. There was a linear relationship between pulmonary pressures and RVEF during exercise in patients with pulmonary artery pressures not exceeding 35 mm Hg. In patients with right ventricular end-diastolic wall thickness 6 mm a curvilinear relationship between these parameters could be observed with a flattening of the curve at higher pressures (>35 mm Hg) and lower ejection fractions (<35% RVEF). Radionuclide venticulography cannot substitute for right heart catheterization. Echocardiography is useful for interpretation of right ventricular ejection fractions in advanced chronic obstructive pulmonary disease.Abbreviations CI Cardiac index (l/min/m²) - CO Cardiac output (l/min) - COPD Chronic obstructive pulmonary disease - FEV₁ Forced expiratory volume in the first second (ml) - HR Heart rate (B/min) - PAd Pulmonary artery diastolic pressure (mm Hg) - PAP Pulmonary artery mean pressure (mm Hg) - PAs Pulmonary artery peak pressure (mm Hg) - PVR Pulmonary vascular resistance (dyn·s·cm^–5) - PwP Pulmonary capillary wedge pressure (mm Hg) - RAP Right arterial pressure (mm Hg) - Raw Airway resistance (cm H₂/l/s) - RNV Radionuclide ventriculogram - RV Residual volume (l) - RVEF Right ventricular ejection fraction (%) - RVEDVI Right ventricular enddiastolic volume index (ml/m²) - RVEDVI SVI RVEF (ml/m²) - RVESVI Right ventricular endsystolic index (m²/m²) - SVI Stroke volume index (ml/m²) - TLC Total lung capacity (l) - VC Vital capacity (l)     

Effects of naloxone on the control of breathing in children with chronic obstructive pulmonary disease

The effect of naloxone on occlusion pressure (P0.1), the pattern of breathing and the expiratory flows during spontaneous ventilation was studied in 16 children with chronic obstructive pulmonary disease under control conditions, after isotonic saline injection and 5 (N5) and 25 (N25) min after i.v. injection of naloxone (2 micrograms X kg-1). At N5, no change was observed in tidal volume normalized for body weight (VTBW), inspiratory time (TI), respiratory frequency (f), mean inspiratory flow (VTBW/TI) and the ratio of TI and total duration of the respiratory cycle (TI/TT). P0.1 decreased significantly (p less than 0.001) at N5 and returned to control values at N25. The decrease in P0.1 without any change in the breathing pattern suggests that naloxone has an effect on respiratory mechanics. Indeed, at N5, the expiratory flows generated at 25% of VT, measured on the flow-volume curves during spontaneous ventilation, increased significantly when compared to control values. Moreover, the decrease of P0.1 after naloxone was found to be correlated to the reduction of dynamic lung compliance (CLdyn) (p less than 0.02). It is speculated that peripheral airway obstruction, as reflected by the decrease in CLdyn, might be a triggering factor for the release of endorphins. The bronchodilation observed after naloxone could then be due to naloxone's antagonistic effect on endorphin-induced bronchoconstriction.     

Chronic Chlamydia pneumonia infection in patients with chronic obstructive pulmonary disease

The aim of our study was to evaluate the frequency of Chlamydia pneumoniae infection (especially chronic infection) in COPD patients. Microimmunofluorescence method has been applied Chlamydia pneumoniae Micro-IF test (Labsystems) has been used. The levels of specific IgG, IgA and IgM have been estimated in patients' serum. According to serologic criteria, 64.1% of COPD patients and 20.5% of healthy controls appeared to be chronically infected with Chlamydia pneumoniae (p < 0.001). Taking in account COPD severity, persistent Chlamydia pneumoniae infection has been present in 68.2%, 57.1%, and 50% of patients with severe, moderate and mild COPD, respectively. Our study has revealed that chronic Chlamydia pneumoniae infection occurs more frequently in COPD patients than in healthy controls and in patients with severe COPD than in ones with mild and moderate disease. It is possible that persistent Chlamydia pneumoniae infection can initiate or amplify inflammatory reactions in the respiratory tract. The results suggest a need to diagnose chronic Chlamydia pneumoniae infection in COPD patients and, if confirmed, to take an attempt of antimicrobial therapy.     

Analysis of microbiota in stable patients with chronic obstructive pulmonary disease

To identify the bacterial diversity (microbiota) in expectorated sputum, a pyrosequencing method that investigates complex microbial communities of expectorated sputum was done in 19 stable chronic obstructive pulmonary disease patients (mean (SD) FEV1: 47 (18%) of predicted value). Using conventional culture, 3 phyla and 20 bacterial genera were identified, whereas the pyrosequencing approach detected 9 phyla and 43 genera (p < 0.001). In sputum the prevalent genera with pyrosequencing approach were Streptococcus, Actinomyces, Neisseria, Haemophilus, Rothia, Fusobacterium, Gemella, Granulicatella, Porphyromonas, Prevotella and Veillonella. Enterobacteriaceae, detected frequently in conventional culture, were not significantly detected with pyrosequencing methods. In addition, we found that important pathogens such as Haemophilus and Moraxella were detected more frequently with the new genetic procedures. The presence of Enterobacteriaceae is probably overestimated with conventional culture, whereas other difficult cultivable pathogens are underestimated. These studies open a new perspective for evaluating the role of bacterial colonization in chronic obstructive pulmonary disease pathogenesis and progression.     

The safety of ECT in patients with chronic obstructive pulmonary disease

BACKGROUND: Electroconvulsive therapy (ECT) involves the administration of general anesthesia and assisted ventilation while the patient is apneic. OBJECTIVE: Care must be taken to screen for significant pulmonary dysfunction before treatment. Very little has been written about the safety and management strategy of ECT patients with chronic obstructive pulmonary disease (COPD). METHOD: In this retrospective chart review, authors describe their experience with patients in recent years who had this disorder and were treated with ECT. RESULTS: Authors list recommendations for the pre-ECT work up and anesthetic management during and after the treatments. CONCLUSION: Recent guidelines recommend administration of patients' prescribed inhalers on the morning of ECT treatment. Also, caution is recommended when using ECT in patients taking theophylline because this drug has been associated with prolonged seizures and status epilepticus in these patients.     

Preoperative pulmonary rehabilitation in patients with non-small cell lung cancer and chronic obstructive pulmonary disease

Introduction

The aim of this study was to assess the effects of preoperative pulmonary rehabilitation (PPR) on preoperative clinical status changes in patients with chronic obstructive pulmonary disease (COPD) and non-small cell lung cancer (NSCLC), and net effects of PPR and cancer resection on residual pulmonary function and functional capacity.

Material and methods

This prospective single group study included 83 COPD patients (62 ±8 years, 85% males, FEV₁ = 1844 ±618 ml, Tiffeneau index = 54 ±9%) with NSCLC, on 2–4-week PPR, before resection. Pulmonary function, and functional and symptom status were evaluated by spirometry, 6-minute walking distance (6MWD) and Borg scale, on admission, after PPR and after surgery.

Results

Following PPR significant improvement was registered in the majority of spirometry parameters (FEV₁ by 374 ml, p < 0.001; VLC by 407 ml, p < 0.001; FEF₅₀ by 3%, p = 0.003), 6MWD (for 56 m, p < 0.001) and dyspnoeal symptoms (by 1.0 Borg unit, p < 0.001). A positive correlation was identified between preoperative increments of FEV₁ and 6MWD (r _s = 0.503, p = 0.001). Negative correlations were found between basal FEV₁ and its percentage increment (r _s = –0.479, p = 0.001) and between basal 6MWD and its percentage change (r _s = –0.603, p < 0.001) during PPR. Compared to basal values, after resection a significant reduction of most spirometry parameters and 6MWD were recorded, while Tiffeneau index, FEF₂₅ and dyspnoea severity remained stable (p = NS).

Conclusions

Preoperative pulmonary rehabilitation significantly enhances clinical status of COPD patients before NSCLC resection. Preoperative increase of exercise tolerance was the result of pulmonary function improvement during PPR. The beneficial effects of PPR were most emphasized in patients with initially the worst pulmonary function and the weakest functional capacity.     

运动锻炼对慢性阻塞性肺疾病患者肺康复的干预效果

慢性阻塞性肺疾病(chronic obstructive pulmonary disease,COPD)是一种具有气流受限特征,可以预防和治疗的慢性疾病。该疾病患病率和病死率较高,且严重影响患者的生命质量,给患者家庭和社会带来沉重的经济负担。运动锻炼可以改善COPD患者的呼吸困难和疲劳状况,提高运动能力、肌肉力量和生活质量,还能减少住院率。研究表明,不同类型的运动锻炼对COPD的干预效果存在差异,如步行锻炼可以改善COPD患者的身体功能和运动耐受性,传统抗阻运动锻炼可以改善COPD患者的上下肢肌肉强度和运动能力。本文综述了不同类型的有氧运动和抗阻运动对不同病程COPD患者的干预效果,强调了运动处方个性化的重要性,并讨论了运动风险和规避方法,为慢阻肺患者的运动康复提供指导性建议。     

Different inflammatory cell pattern and macrophage phenotype in chronic obstructive pulmonary disease patients, smokers and non-smokers

Smokers exhibit airway inflammation and increased number of alveolar macrophages (AM), but not all develop chronic obstructive pulmonary disease (COPD). We hypothesized that AMs in COPD patients have an altered functional capacity mirrored in a different phenotype. Sixteen steroid-naive COPD patients [forced expiratory volume in 1 s (FEV(1)) < 70% of predicted] underwent bronchoalveolar lavage (BAL). Age- and smoking-matched non-obstructive smokers (n = 10) and healthy non-smokers (n = 9) served as controls. Nine COPD patients had a BAL cell yield sufficient for flow cytometry analysis, where expression of AM cell surface markers reflecting various functions was determined. AMs from COPD patients showed decreased expression of CD86 (co-stimulation) and CD11a (adhesion) compared to smokers' AMs (P < 0.05). Furthermore, smokers' AMs showed lower (P < 0.05) expression of CD11a compared to non-smokers. AM expression of CD11c was higher in the COPD and smokers groups compared to non-smokers (P < 0.05). The expression of CD54 (adhesion) was lower in smokers' AMs compared to non-smokers (P < 0.05), whereas CD16 was lower (P < 0.05) in COPD patients compared to non-smokers. The AM expression of CD11b, CD14, CD58, CD71, CD80 and human leucocyte antigen (HLA) Class II did not differ between the three groups. The AM phenotype is altered in COPD and further research may develop disease markers. The lower AM expression of CD86 and CD11a in COPD implies a reduced antigen-presenting function. Some alterations were found in smokers compared to non-smokers, thus indicating that changes in AM phenotype may be associated with smoking per se. The functional relevance of our findings remains to be elucidated.     

Potential drug-drug interactions in hospitalized patients with chronic heart failure and chronic obstructive pulmonary disease

Introduction

Polypharmacy is common in patients with chronic heart failure (HF) and/or chronic obstructive pulmonary disease (COPD), but little is known about the prevalence and significance of drug-drug interactions (DDIs). This study evaluates DDIs in hospitalized patients.

Material and methods

We retrospectively screened medical charts over a 6-month period for diagnosis of chronic HF and/or COPD. Potential DDIs were evaluated using Lexi-Interact software.

Results

Seven hundred and seventy-eight patients were included in the study (median age 75 years, 61% men). The median number of drugs on admission and discharge was 6 (interquartile range (IQR) 4–9) and 7 (IQR 5–), respectively (p = 0.10). We recorded 6.5 ±5.7 potential DDIs per patient on admission and 7.2 ±5.6 on discharge (p = 0.2). From admission to discharge, type-C and type-X potential DDIs increased (p < 0.05 for both). Type X interactions were rare (< 1%), with the combination of a β-blocker and a β₂ agonist being the most common (64%). There were significantly more type-C and type-D potential DDIs in patients with chronic HF as compared to patients with COPD (p < 0.001). Patients with concomitant chronic HF and COPD had more type-C and type-X potential DDIs when compared to those with individual disease (p < 0.005). An aldosterone antagonist and ACE inhibitor/ARB were prescribed to 3% of chronic HF patients with estimated glomerular filtration rate < 30 ml/(min × 1.73 m²).

Conclusions

The DDIs are common in patients with chronic HF and/or COPD, but only a few appear to be of clinical significance. The increase in potential DDIs from admission to discharge may reflect better guideline implementation rather than poor clinical practice.