Maximal Mid-expiratory Flow Rate Research Articles

Comparison of Forced Oscillation Technique, Lung Volumes by Body Plethysmography, and Spirometry in Moderate Persistent Adult Asthma.

Spirometry is used extensively, but airway oscillometry is gaining acceptance for evaluating obstructive airway disorders. Moderate persistent asthma requires daily treatment with inhaled corticosteroids (ICS). We aimed to examine the relationship between airway oscillometry and lung volumes, which are the markers of lung physiology in obstructive airway disease and spirometry in the real-world clinical setting. A total of 72 adults with moderate persistent asthma followed up in our outpatient department from November 2021 to August 2022, and their clinical details and tests of spirometry, forced oscillation technique (FOT), and lung volumes by body plethysmography (BP) performed before and after bronchodilator administration were analyzed. The mean age of the study population was 40 years, and the majority (57%) were females. FOT detected airflow limitation in 12 of the 31 patients with normal spirometry. BP detected abnormalities in more patients than both spirometry and FOT (91.6 vs 73.6%, p < 0.001). Respiratory resistance 5 (R5) had a negative correlation with functional residual capacity (FRC) and total lung capacity (TLC). Reactance 5 (X5) correlated positively with inspiratory capacity (IC) and TLC and negatively with reserve volume (RV)/TLC ratio. A positive correlation was found between IC/TLC% and postbronchodilator X5 and between R5 and 19 and RV/TLC. R5 had a negative and X5 had a positive correlation with forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), FEV1/FVC, and maximal mid expiratory flow rates (MMEF). ∇X5 had a negative correlation with FEV1, MMEF, and FEV1/FVC. Spirometry detected postbronchodilator responsiveness in more patients than FOT when only the R5 criterion was used and in a comparable number when the X5 criterion was added. ∇X5 and R5-R19/R5 declined significantly after bronchodilators. We concluded that there is a moderate correlation between FOT and spirometry and lung volumes by BP. FOT and spirometry should be used together to identify airflow obstruction and postbronchodilator responsiveness in asthma. Lung volumes by BP identify more abnormalities in adults with asthma than both spirometry and FOT. Thresholds to define postbronchodilator responsiveness (PBDR) for ∇X5 and R5-R19 need to be defined.

Usefulness of Computed Tomography for Evaluating the Effects of Bronchial Thermoplasty in Japanese Patients with Severe Asthma.

Bronchial thermoplasty (BT) improves clinical outcomes and quality of life for patients with severe asthma and has shown sustained reductions in airway narrowing and air trapping in previous CT studies. However, there is a lack of a comprehensive analysis, including CT evaluation, of clinical outcomes in Japanese patients who have undergone BT for severe asthma. This study aimed to evaluate the impact of BT in Japanese asthma patients, with a focus on the CT metric "WA at Pi10" to assess airway disease. Twelve patients with severe persistent asthma who underwent BT were assessed using ACQ6, AQLQ, pulmonary function tests, FeNO measurement, blood sampling, and chest CT before BT and one year after the third procedure for the upper lobes. The median age of the patient was 62.0 years, 7/12 (58.3%) were male, 4/12 (33.3%) used regular oral corticosteroids, and 8/12 (66.7%) received biologics. Median FEV1% was 73.6%, and median peripheral eosinophil count was 163.8/μL. After one year of BT, ACQ6 scores improved from 2.4 to 0.8 points (p = 0.007), and AQLQ scores improved from 4.3 to 5.8 points (p < 0.001). Significant improvements were also observed in asthma exacerbations, unscheduled visits due to exacerbations, FeNO, and √WA at Pi10 (p < 0.05). The baseline mucus score on the CT findings was negatively correlated with FEV1 (r = -0.688, p = 0.013) and with the maximum mid-expiratory flow rate (r = -0.631, p = 0.028), and positively correlated with the peripheral blood eosinophil count (r = -0.719, p = 0.008). Changes in √WA at Pi10 after one year were positively correlated with changes in the mucus score (r = 0.742, p = 0.007). This study has limitations, including its single-arm observational design and the small sample size. However, BT led to a symptomatic improvement in patients with severe asthma. The validated "√WA at Pi10" metric on CT effectively evaluated the therapeutic response in Japanese asthma patients after BT.

Evaluation of Spirometric Values in Healthy Population Referred to Spirometry Centers in Hamedan City, Iran

Background: Spirometry procedure is known to be an efficient test for evaluating lung function. Nevertheless, the ventilatory function indexes acquired by spirometry seem to have been affected by several factors, some of which are demographic and anthropometric parameters. Hence, our study aimed to address the effect of some specific features of Hamedani individuals in Iran on spirometric characteristics.&#x0D; Methods: We assessed the spirometric parameters, including Forced Vital Capacity (FVC), forced expiratory volume in the first second (FEV1), maximal mid-expiratory flow rate (FEF25-75), and FEV1/FVC ratio, obtained from normal spirometry test of 1483 individuals between the ages of 16 and 89 years.&#x0D; Results: FVC, FEV1, FEV1/FVC ratio, and FEF25-75 were different between the two genders significantly (p&lt;0.001). Even though there was a higher FVC, FEV1, and FEF25-75 in males, FEV1/FVC ratios for males were significantly lower than the ratios for females at the same ages (total mean of 82.09±6.78 in males versus 84.94±6.49 for females). In addition, FEV1/FVC ratio and FEF25-75 were not significantly different between tall males and females with a height of &gt;170 cm. Finally, age and stature influenced the ventilatory function values with a correlation strength of &lt;0.001.&#x0D; Conclusion: Albeit men, mostly because of their particular anatomic and physiologic feature of respiratory muscles, had larger FVC and FEV1, those who were tall showed no significant change in FEV1/FVC ratio and FEF25-75, in comparison with females. Irrespective of their height, men found a higher FEF25-75 as well.

Inhaled Marijuana and the Lung

Although vaping has recently increased as a mode of inhaling marijuana and has been associated with numerous and sometimes fatal cases of acute severe lung injury, smoking remains the most common method of inhaling marijuana and has been studied more extensively. Smoking marijuana has been shown to produce modest but significant short-term bronchodilation both in healthy subjects and in those with asthma. Long-term effects of habitual marijuana smoking include the following: (1) symptoms of chronic bronchitis (increased cough, sputum production, and wheezing); (2) modest effects on lung function in cross-sectional studies (no significant decrease in FEV1 but mild reductions in FEV1/forced vital capacity ratio, an increase in forced vital capacity and other lung volumes, reductions in specific airway conductance, and variable effects of maximal midexpiratory flow rates and diffusing capacity); and (3) variable effects on age-related decline in FEV1 in longitudinal studies. Most cohort and case-control studies have failed to show that marijuana smoking is a significant risk factor for lung cancer despite the presence of procarcinogenic components in marijuana smoke, although further study is warranted. The question whether marijuana smoking is associated with asthma is unclear and requires further investigation. Although delta-9 tetrahydrocannabinol, the principal psychoactive component of marijuana, has immunomodulatory properties that hypothetically could increase the risk of pneumonia, the few available studies in marijuana smokers have failed to find an increased risk of pneumonia in immunocompetent users, although effects in immunosuppressed individuals have been variable.

The Investigation of Pulmonary Function Changes of COVID-19 Patients in Three Months.

Background Novel coronavirus disease 2019 (COVID-19) was discovered in December 2019 and has infected more than 80 million people worldwide, and more than 50 million people have achieved a clinical cure. In this study, the pulmonary function results of patients after clinical medicine for three months were reported. Objective To investigate the effect of COVID-19 on lung function in patients. Methods A retrospective analysis was performed on 56 COVID-19-infected patients who were cured after the clinical treatment at Taizhou Public Health Medical Center in Zhejiang Province from January 31, 2020, to March 10, 2020. At discharge and three months after discharge, lung function was measured, including inspiratory vital capacity (IVC), forced vital capacity (FVC), forced expiratory volume in first second (FEV1), forced expiratory volume in first second to inspiratory vital capacity (FEV1/IVC), maximum mid-expiratory flow rate (MEF), peak expiratory flow rate (PEF), and carbon monoxide dispersion (DLCO). Results At discharge, there were 37 patients (66.1%) with pulmonary dysfunction, 22 patients (39.3%) with ventilation dysfunction, 31 cases (55.4%) with small airway dysfunction, and 16 cases (28.6%) with restricted ventilation dysfunction combined with small airway dysfunction. At 3 months after discharge, 24 of the 56 patients still had pulmonary dysfunction and all of them had small airway dysfunction, of which 10 patients (17.9%) were restricted ventilation dysfunction combined with small airway dysfunction. DLCO was measured three months after discharge. Twenty-nine patients (51.8%) had mild to moderate diffuse dysfunction. All pulmonary function indexes of 56 patients recovered gradually after 3 months after release, except FEV1/IVC, and the difference was statistically significant (P < 0.05). There were 41 patients of normal type (73.2%) and 15 patients of severe type (26.8%). Among the 15 severe patients, 8 patients (53.3%) had ventilation dysfunction at discharge, 9 patients (60%) had small airway dysfunction, 4 patients (26.7%) still had ventilation dysfunction 3 months after discharge, 7 patients (46.7%) had small airway dysfunction, and 10 patients (66.7%) had diffuse dysfunction. Among the 41 common type patients, 14 patients (34.1%) had ventilation dysfunction at discharge, 22 patients (53.7%) had small airway dysfunction, 6 patients (14.6%) still had ventilation dysfunction 3 months after discharge, 17 patients (41.5%) had small airway dysfunction, and 19 patients (46.3%) had diffuse dysfunction. Patients with severe COVID-19 had more pulmonary impairment and improved pulmonary function than normal patients. Conclusion COVID-19 infection can cause lung function impairment, manifested as restricted ventilation dysfunction, small airway dysfunction, and diffuse dysfunction. The pulmonary function of most patients was improved 3 months after clinical cure and discharge, and some patients remained with mild to moderate diffuse dysfunction and small airway dysfunction.

Forced Expiratory Flow at 25%-75% Links COPD Physiology to Emphysema and Disease Severity in the SPIROMICS Cohort.

Forced expiratory volume in 1 second (FEV1) is central to the diagnosis of chronic obstructive pulmonary disease (COPD) but is imprecise in classifying disease burden. We examined the potential of the maximal mid-expiratory flow rate (forced expiratory flow rate between 25% and 75% [FEF25%-75%]) as an additional tool for characterizing pathophysiology in COPD. To determine whether FEF25%-75% helps predict clinical and radiographic abnormalities in COPD. The SubPopulations and InteRediate Outcome Measures In COPD Study (SPIROMICS) enrolled a prospective cohort of 2978 nonsmokers and ever-smokers, with and without COPD, to identify phenotypes and intermediate markers of disease progression. We used baseline data from 2771 ever-smokers from the SPIROMICS cohort to identify associations between percent predicted FEF25%-75% (%predFEF25%-75%) and both clinical markers and computed tomography (CT) findings of smoking-related lung disease. Lower %predFEF25-75% was associated with more severe disease, manifested radiographically by increased functional small airways disease, emphysema (most notably with homogeneous distribution), CT-measured residual volume, total lung capacity (TLC), and airway wall thickness, and clinically by increased symptoms, decreased 6-minute walk distance, and increased bronchodilator responsiveness (BDR). A lower %predFEF25-75% remained significantly associated with increased emphysema, functional small airways disease, TLC, and BDR after adjustment for FEV1 or forced vital capacity (FVC). The %predFEF25-75% provides additional information about disease manifestation beyond FEV1. These associations may reflect loss of elastic recoil and air trapping from emphysema and intrinsic small airways disease. Thus, %predFEF25-75% helps link the anatomic pathology and deranged physiology of COPD.

Association between eye-level greenness and lung function in urban Chinese children

BackgroundHealth effects of greenness perceived by residents at eye level has received increasing attention. However, the associations between eye-level greenness and respiratory health are unknown. The aim of the study was to investigate the associations between exposure to eye-level greenness and lung function in children. MethodsFrom 2012 to 2013, a total of 6740 school children in seven cities in northeast China were recruited into this cross-sectional study. Forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), peak expiratory flow rate (PEF), and maximum mid expiratory flow rate (MMEF) were measured to evaluate lung function and to define lung impairment. Eye-level greenness was extracted from segmented Tencent Map street view images, and a corresponding green view index (GVI) was calculated. Higher GVIs mean more greenness coverage. Mixed-effects logistic regressions were used to estimate the health effects on lung impairment per interquartile range (IQR) increase in GVI. Linear regressions were used to estimate the associations between GVI and lung function. The health effects of ambient air pollutants were also assessed, including particulate matter with an aerodynamic diameter <1.0 μm (PM1), <2.5 μm (PM2.5), <10 μm (PM10) as well as nitrogen dioxide (NO2). ResultsAn increase of GVI800m was associated with lung impairment in FEV1, FVC, PEF and MMEF, with ORs ranging from 0.68 (95% CI: 0.59, 0.79) to 0.83 (95% CI: 0.74, 0.93). The associations between an IQR increase of GVI800m and FEV1 (48.15 ml, 95% CI: 30.33–65.97 ml), FVC (50.57 ml, 95% CI: 30.65–70.48 ml), PEF (149.59 ml/s, 95% CI: 109.79–189.38 ml/s), and MMEF (61.18 ml/s, 95% CI: 31.07–91.29 ml/s) were significant, and PM1, PM2.5, and PM10 were found to be mediators of this relationship. ConclusionMore eye-level greenness was associated with better lung function and reduced impairment. However, eye-level greenness associations with lung function became non-significant once lower particulate matter air pollution exposures were considered.

Respiratory health of workers exposed to polyacrylate dust.

Background:Polyacrylate (PA) powder dust formed in PA manufacturing units is fine sized, i.e., in nanosize. Although several previous studies reported possible significant adverse effects of nanomaterials, studies on the harmful effect of small-sized PA particles on the respiratory health of the workers are scarce. The present study was carried out to assess the effect of PA on respiratory health and lung volumes/rates among the workers of PA manufacturing unit.Materials and Methods:The present cross-sectional study included 84 workers of PA manufacturing unit. Using interview technique as a tool for data collection, demographic, occupational, and clinical details of the workers were recorded on the predesigned pro forma. This was followed by detailed clinical examination, spirometry, chest X-ray (posteroanterior [PA] view), and high-resolution computed tomography (HRCT) examination of each worker.Results:On the basis of clinical examination, chest radiography, and HRCT, 17.9% of the workers were found to have fibrotic and cavitarychanges in lung parenchyma. The production department workers had a higher proportion of respiratory morbidities as compared to supervisory or office staff. Age, gender, smoking habit, and duration of exposure were nonsignificant risk factors for respiratory morbidity. The overall mean forced vital capacity, forced expiratory volume in 1sts, Peak Expiratory Flow Rate (PEFR), (Maximal Mid Expiratory Flow Rate) MMEFR0.2–1.2, and MMEFR25%–75% were 3.19 ± 0.77 L, 2.72 ± 0.67 L, 6.82 ± 1.86 L/s, 5.79 ± 2.03 L/s, and 3.16 ± 1.19 L/s, respectively. Females and those having respiratory morbidity had significantly lower values of all spirometric parameters as compared to their counterparts.Conclusions:The workers exposed to engineered fine dust of PA may be at risk of respiratory ill-health.

Rapid effect of benralizumab for severe asthma with chronic rhinosinusitis with nasal polyps

BackgroundThe anti-interleukin (IL)-5 agent benralizumab has recently become available for treatment of severe asthma with promising results; however, it appears effective only in specific subgroups of asthma patients. Severe asthma with chronic rhinosinusitis/nasal polyps (CRSwNP or eosinophilic chronic rhinosinusitis, ECRS) is a severe eosinophilic asthma phenotype that necessitates individualized treatment. ObjectiveTo assess differences in response to benralizumab between severely eosinophilic asthma patients with and without CRSwNP. MethodsSeventeen outpatients with severe eosinophilic asthma treated with benralizumab for 1 year were evaluated at the Osaka Habikino Medical Center. Blood eosinophil count, Asthma Control Questionnaire 5 (ACQ5), Asthma Quality of Life Questionnaire (AQLQ), fractional exhaled nitric oxide (FeNO), and spirometry were recorded at weeks 0, 4, 16, 24, and 50. ResultsACQ5 and AQLQ in CRSwNP(+) groups improved significantly after 4, 16, 24, and 50 weeks (p = 0.0195, 0.0156, 0.0117, and 0.0078 and p = 0.0098, 0.0098, 0.0029, and 0.0098, respectively) of benralizumab treatment. ACQ5 in CRSwNP(−) groups did not improve significantly after benralizumab treatment, but AQLQ improved significantly after 24 (p = 0.0313) and 50 weeks (p = 0.0313). Forced expiratory volume in 1s (FEV1) predicted in CRSwNP(+) groups were improved significantly after 4 weeks (p = 0.0137), 16 weeks (p = 0.0127), 24 weeks (p = 0.0098) and 50 weeks (p = 0.0420) of benralizumab treatment. %FEV1 in CRSwNP(−) groups were improved significantly after 24 weeks (p = 0.0313) and 50 weeks (p = 0.0313) of benralizumab treatment (Fig. 3). Forced vital capacity (FVC) predicted in CRSwNP(+) groups were improved significantly after 24 weeks (p = 0.0195) and %FVC in CRSwNP(−) groups improved significantly after 50 weeks (p = 0.0313) of benralizumab treatment. Maximum mid-expiratory flow rate predicted in CRSwNP(+) groups were improved significantly after 16 (p = 0.0137 and 50 weeks (p = 0.0371) of benralizumab treatment. ConclusionsBenralizumab can exert a very rapid therapeutic action, detectable 4 weeks after treatment initiation in patients with severe eosinophilic asthma with CRSwNP. However, severe eosinophilic asthma without CRSwNP takes longer to respond to benralizumab treatment.

Effectiveness of oral motor respiratory exercise and vocal intonation therapy on respiratory function and vocal quality in patients with spinal cord injury: a randomized controlled trial.

Singing, as a method of combining respiratory function exercise and vocal intonation therapy, provides a new direction for respiratory function exercise in patients with spinal cord injury. This randomized controlled trial investigated the effects of oral motor respiratory exercise and vocal intonation therapy on respiratory function and vocal quality in patients with spinal cord injury. Among 31 included patients with spinal cord injury, 18 completed the treatment. These 18 patients were randomly assigned to undergo music therapy (intervention group, 30 min/d, 5 times a week, for a total of 12 weeks; n = 9, 7 males and 2 females; 30.33 ± 11.74 years old) or normal respiratory training (control group, n = 9; 8 males and 1 female; 34.78 ± 11.13 years old). Both patient groups received routine treatment concurrently. Before and at 6 and 12 weeks after intervention, a standard respiratory function test, a voice test, the St. George's Respiratory Questionnaire, and a quality of life questionnaire were administered. The results showed that the inspiratory capacity, forced expiratory volume in 1 second, forced vital capacity, maximal mid-expiratory flow rate, sing-loud pressure level, and sustained note length were significantly increased in the intervention group compared with the control group. The St. George's Respiratory Questionnaire and quality of life results of patients in the intervention group were significantly superior to those in the control group. These findings suggest that oral motor respiratory exercise and vocal intonation therapy, as respiratory training methods in music therapy, are effective and valuable for improving respiratory dysfunction and vocal quality in patients with spinal cord injury. This study was approved by the Ethics Committee of China Rehabilitation Research Center (approval No. 2019-78-1) on May 27, 2019 and was registered with the Chinese Clinical Trial Registry (registration number: ChiCTR1900026922) on October 26, 2019.

Association of Neutrophil to Lymphocyte Ratio With Pulmonary Function in a 30-Year Longitudinal Study of US Veterans

Chronic obstructive pulmonary disease (COPD) is a critical public health burden. The neutrophil to lymphocyte ratio (NLR), an inflammation biomarker, has been associated with COPD morbidity and mortality; however, its associations with lung function decline and COPD development are poorly understood. To explore the associations of NLR with lung function decline and COPD risks. This longitudinal cohort study included white male veterans in the US with more than 30 years of follow-up to investigate the associations of NLR with lung function, COPD, and hypomethylation of cg05575921, the top DNA methylation marker of lung function changes in response to tobacco smoking. This study included 7466 visits from 1549 participants, each examined up to 13 times between 1982 and 2018. A subgroup of 1411 participants without COPD at baseline were selected to analyze the association of NLR with incident COPD. Data were analyzed from September 2019 to January 2020. The primary exposure was NLR, which was estimated using automated whole blood cell counts based on a blood sample collected at each visit. The methylation level of cg05575921 was measured in blood DNA from a subgroup of 1228 visits. The outcomes of interest were lung function, measured as forced respiratory volume in the first second (FEV1) in liters, forced vital capacity (FVC) in liters, percentage of FVC exhaled in the first second (FEV1/FVC), and maximal midexpiratory flow rate (MMEF) in liters per minute and COPD status, defined as meeting the Global Initiative for Chronic Obstructive Lung Diseases stage II (or higher) criteria. Both outcomes were measured as each visit. Among 1549 included men (mean [SD] age, 68.3 [9.3] years) with 7466 visits from 1982 to 2018, a 1-unit increase in NLR was associated with statistically significant mean (SE) decreases of 0.021 (0.004) L in FEV1, 0.016 (0.005) L in FVC, 0.290% (0.005) L in FVC, 0.290% (0.065%) in FEV1/FVC, and 3.65 (0.916) L/min MMEF. Changes in NLR up to approximately 10 years were associated with corresponding longitudinal changes in lung function. Furthermore, this increase in NLR was associated with 9% higher odds of COPD (odds ratio, 1.09 [95% CI, 1.03-1.15]) for all visits and 27% higher risk of incident COPD (odds ratio, 1.07 [95% CI, 1.07-1.51]) for participants without COPD at baseline. Additionally, a 1-unit increase in NLR was associated with a mean (SE) decrease of 0.0048 (0.0021 in cg05575921 hypomethylation, which may mediate the adverse association of NLR-related inflammation on lung function. These findings suggest that NLR may be a clinically relevant biomarker associated with high risk of lung function impairment and COPD alone or in combination with DNA methylation profiles.

Pattern of Pulmonary Dysfunctions in Craniovertebral Junction Anomaly and Its Persistence after Rigid Occipitocervical Fixation

Abstract Introduction Despite a significant advancement in operative techniques of occipitocervical fixation, there is a poor postoperative patient outcome. This can be attributed to restrictive lung pattern in craniovertebral junction anomalies (CVJAs) patients resulting from repeated trauma to cervicomedullary junction by the pincer action of the bony anomalies and compression of the brainstem. We evaluate the changes in pulmonary function tests (PFTs) following rigid occipitocervical fixation in CVJA. Methods PFTs of 20 CVJA patients were measured pre and postoperatively using spirometry. Measurements included forced vital capacity (FVC), forced expiratory volume in one second (FEV1), maximum forced mid-expiratory flow rate (FEF25–75%), and ratio of FEV1 and FVC (FEV1%). The parameters were compared with the predicted normal values based on their age and sex. PFTs were repeated on the seventh postoperative day. McCormick grading was used to assess neurological function. Results The values of PFTs in the preoperative period were significantly lower than predicted normal values. The mean values of FVC, FEV1, FEF25–75% were 72, 68, and 71% of their mean predicted values, with FEV1% in the range of 70 to 95% with a mean of 81.4%. Postoperatively there was further significant reduction in the mean values of FVC, FEV1, FEF25–75%, and FEV1% compared with the preoperative values. There was neurological improvement in McCormick grades of patients postoperatively (from grade III and IV to grade II). Conclusion A significant restrictive lung disease is present in patients of CVJA, even though not clinically apparent, and it persists in the early postoperative period. However, a long-term follow-up is required to assess whether pulmonary function parameters improve subsequently.

Reference value for expiratory time constant calculated from the maximal expiratory flow-volume curve

BackgroundThe expiratory time constant (RCEXP), which is defined as the product of airway resistance and lung compliance, enable us to assess the mechanical properties of the respiratory system in mechanically ventilated patients. Although RCEXP could also be applied to spontaneously breathing patients, little is known about RCEXP calculated from the maximal expiratory flow-volume (MEFV) curve. The aim of our study was to determine the reference value for RCEXP, as well as to investigate the association between RCEXP and other respiratory function parameters, including the forced expiratory volume in 1 s (FEV1)/ forced vital capacity (FVC) ratio, maximal mid-expiratory flow rate (MMF), maximal expiratory flow at 50 and 25% of FVC (MEF50 and MEF25, respectively), ratio of MEF50 to MEF25 (MEF50/MEF25).MethodsSpirometric parameters were extracted from the records of patients aged 15 years or older who underwent pulmonary function testing as a routine preoperative examination before non-cardiac surgery at the University of Tokyo Hospital. RCEXP was calculated in each patient from the slope of the descending limb of the MEFV curve using two points corresponding to MEF50 and MEF25. Airway obstruction was defined as an FEV1/FVC and FEV1 below the statistically lower limit of normal.ResultsWe retrospectively analyzed 777 spirometry records, and 62 patients were deemed to have airway obstruction according to Japanese spirometric reference values. The cut-off value for RCEXP was 0.601 s with an area under the receiver operating characteristic curve of 0.934 (95% confidence interval = 0.898–0.970). RCEXP was strongly associated with FEV1/FVC, and was moderately associated with MMF and MEF50. However, RCEXP was less associated with MEF25 and MEF50/MEF25.ConclusionsOur findings suggest that an RCEXP of longer than approximately 0.6 s can be linked to the presence of airway obstruction. Application of the concept of RCEXP to spontaneously breathing subjects was feasible, using our simple calculation method.

The level of exhaled nitric oxide and its clinical significance in children with Mycoplasma pneumoniae pneumonia

Objective To investigate the changes of levels of exhaled nitric oxide and the clinical significance in children with Mycoplasma pneumoniae pneumonia(MPP). Methods From June 2014 to March 2017, 95 children with MPP and 64 children with bronchial pneumonia in Jinshan Branch of The Sixth People's Hospital of Shanghai were collected, 32 healthy children were enrolled as controls.According to the imaging examination, patients with MPP were further grouped into lobar pneumonia group, bronchopneumonia group and interstitial pneumonia group.FeNO and lung function were measured in all children. Results The level of FeNO in the MPP group was (7.25±3.41) ppb, which was lower than that in the non-MPP group and control group[(11.24±3.52)ppb, (10.51±4.23)ppb](t=5.82, 5.77, all P 0.05). The FEV1, FEV1/FVC%, FEF25%-75% of the MPP group[(66.23±13.21), (84.62±6.73), (58.65.±19.43)]were lower than those of the control group and non-MPP group[(91.81±11.36), (93.80±8.91), (86.80±20.71); (85.43±10.32), (90.18±11.35), (74.73±17.91)](t=4.35, 3.62, 4.78; 4.56, 7.12, 5.06, all P 0.05). In the MPP group, the FEV1, FEV1/FVC%, FEF25%-75% were not associated with FeNO level(r=-0.15, P>0.05; r=-0.06, P>0.05; r=0.07, P>0.05). Conclusion The level of FeNO in children with MPP is lower, and the level of FeNO is not significantly correlated with the parameters of lung function, and FeNO can be used as an inflammatory marker to evaluate the correlation between MP infection and airway inflammation. Key words: Pneumonia, mycoplasma; Nitric oxide; Maximal midexpiratory flow rate; Forced expiratory volume; Child

IMPACT OF OBESITY ON PULMONARY FUNCTIONS AMONG YOUNG NON-SMOKER HEALTHY FEMALE OF SHAH ALAM, MALAYSIA

Objectives: The sedentary lifestyle, physical inactivity, and unhealthy diet of Malaysian female have become important contributing factors to the rise of obesity. Studies on pulmonary function in relation to obesity are very few in Malaysia. Therefore, the study was aimed to evaluate the effect of obesity on pulmonary functions among young adult healthy female students of Shah Alam, Malaysia.Methods: A cross-sectional comparative study was conducted in a total of 100 (50 obese and 50 non-obese) adult non-smoker healthy female students aged 18–25 years. Forced vital capacity (FVC), forced expiratory volume in 1 sec (FEV1), FEV1 as a percentage of FVC (FEV1/FVC%), maximum midexpiratory flow rate (FEF 25–75%), and peak expiratory flow rate (PEFR) were measured using a computerized spirometer. Body weight, height, waist circumference (WC), and hip circumference (HC) were measured.Results: The mean FVC (L), FEV1 (L), FEV1/FVC ratio, FEF 25–75% (L/s), and PEFR (L/s) of obese group were marginally lower than non-obese control group, but the differences were not statistically significant. WC and waist–hip ratio exhibited significant (p&lt;0.05) inverse correlation with all pulmonary function measurements except FEV1/FVC%. However, body mass index had no significant correlation with any spirometric variables in studied obese females.Conclusion: There was no significant effect of obesity on pulmonary functions in the studied Malaysian females. However, abdominal obesity had more impact on the impairment of pulmonary functions than overall relative obesity.

Evaluation of Noncystic Fibrosis Bronchiectasis Using Clinical and Radiological Scorings in Children.

The aim of this study was to evaluate radiological, clinical, and demographic data of patients with noncystic fibrosis bronchiectasis and to compare high-resolution computed tomography (HRCT) scores based on the demographic and clinical characteristics. A total of 34 patients (18 male, 16 female) were assessed in terms of age at symptom onset, age at diagnosis, annual attack frequency, cough severity score, physical examination findings, and pulmonary function test results. Modified Bhalla scoring system (B total) and anatomical prevalence degree score (D total) were used for HRCT examination. There was a strong negative correlation between forced expiratory volume at first second (FEV1) and bronchial dilatation degree (SBRDIL). There was a moderate negative correlation of FEV1, forced vital capacity (FVC), and maximum mid-expiratory flow rate (MEF; 25-75) with bronchiectasis degree (EXBRNC), bronchial wall thickness degree (SBWTHICK), and mucus accumulation in the major airways (PMPLA). The B total, D total, EXBRNC, and SBRDIL scores were significantly higher in patients with hemoptysis and sputum. In comparing B and D total scoring systems, B total provided better results in terms of rale, annual exacerbation frequency (AEF), cough severity score (CSS), and FEV1 values. As it is proved using HRCT, pulmonary function impairment, sputum production, hemoptysis, and increase in AEF strongly correlating with objective HRCT scoring can be accepted as markers for pathological changes due to bronchiectasis.

Effect of Different Concentrations of Moxa-smoke on Lung Function and TNF-α and IL-1 β Levels in Serum and Lung Tissues in Normal Rats

To study the effect of moxa-smoke inhaling on the respiratory system, so as to provide experimental data and theoretical basis for evaluating the safety of moxa-smoke inhaling during moxibustion treatment. A total of 48 SD rats were randomized into control, low, medium and high moxa-smoke-concentration groups (n＝12 in each group). The low, medium and high concentrations of smoke were controlled in (0.11±0.05) mg/m3, (0.23±0.05) mg/m3 and (0.53±0.05) mg/m3 respectively in each of 3 glass boxes (with reference to the level of PM 2.5). The smoking was conducted 4 hours each time, twice a day for 100 days. The normal group did not receive any moxa-smoke inhaling. The histopathological changes of lung and bronchial tissues were detected by H．E. stainning, and the contents of TNF-α and IL-1 β of plasma, bronchoalveolar la-vage fluid (BALF) and lung tissue detected by ELISA. The levels of forced vital capacity (FVC), forced expiratory volume (FEV), FEV 0.3/FVC (0.3＝ the 0.3rd second), maximal mid-expiratory flow rate(MMEF), peak expiratory flow(PEF) were detected by animal pulmonary function analysis system. After 100 days' moxa-smoke inhaling, the contents of TNF-α in the plasma, BALF and lung tissues and IL-1 β in the lung tissue of the low, medium and high concentration moxa-smoke groups, and IL-1 β in the plasma and BALF of the medium and high concentration groups were significantly increased relevant to the control group (P<0.05, P<0.01). H．E. stain showed various inflammatory changes in the lungs and trachea tissues, including obvious fusion of pulmonary alveoli, lymphocyte infiltration, increase of capillary permeability, red blood cell exudation, etc. in the high concentration group, these situations were milder in the medium concentration group and were not obvious in the low concentration group. Compared with the control group, there were no significant changes in the FVC, FEV, FEV 0.3/FVC, MMEF and PEF of lung function in the three concentration groups (P> 0.05)．. Long term inhalation of high concentration of moxa-smoke may lead to inflammatory injury in the lung and bronchial tissues but has no significant effect on the respiratory function in rats. Nevertheless, a good air-ventilation during moxibustion in a treatment room is necessary.

Pernafasan Active Cycle of Breathing Meningkatkan Aliran Ekspirasi Maksimum Penderita Tuberkulosis Paru

Introduction: Tuberculosis bacterial can cause fibrosis tissue in lung. Fibrosis decrease elasticity and compliance of lung as a result, there will be air ventilation and oxygenation disorder, thus it will decrease peak expiratory flow rate (PEFR). The objective of this study was to analyze the effect of active cycle of breathing technique on raised peak expiratory flow rate (PEFR). Method: A quasy experimental purposive sampling design was used in this study. There were 14 sample who met in inclusion criteria divided into 7 subjects for intervention group and 7 subject for control group. Data were analyzed by using Paired t-Test, Independent t-Test, Wilcoxon Signed Rank Test, and Mann Whitney U Test with significance level α≤0.05. Result: The result showed that active cycle of breathing had significance level on increased peak expiratory flow rate (PEFR) (p=0.001). Discussion: It can be concluded that active cycle of breathing has effect on raise peak expiratory flow rate. Further study are recommended to measure the effect of active cycle of breathing on raised maximum midexpiratory flow rate (MMFR50-75%).

Correlation of Cobb's angle with pulmonary function in idiopathic scoliosis

Background: Idiopathic scoliosis, which accounts for the 80-85% of all lateral spine curvatures, distorts the chest wall anatomy and results in functional pulmonary disability. Aims and Objectives: The aim of this study is to evaluate the pulmonary function in patients with asymptomatic idiopathic scoliosis and matched controls and to study the correlation between the degree of spinal deformity (Cobb’s angle) and pulmonary function test (PFT) parameters. Materials and Methods: This study included 35 (27 males and 8 females) patients with idiopathic scoliosis in the age group of 15-30 years, with mean Cobb’s angle 62°. Standing anteroposterior X-rays of the spine were taken. The radiographs were assessed and angle of curvature was measured by the Cobb’s method. PFT parameters were recorded and compared with matched controls, and their correlation with Cobb’s angle was studied. The data were analyzed with the Student’s unpaired t-test and Pearson’s correlation coefficient. Results: Pulmonary parameters such as tidal volume, vital capacity (VC), forced VC (FVC), forced expiratory volume in first second (FEV1), maximum mid-expiratory flow rate, peak expiratory flow rate, and maximum voluntary ventilation were significantly reduced in scoliosis patients than controls, and they were inversely correlated with Cobb’s angle. However, the mean FEV1/FVC ratio at rest in scoliosis patients was within normal limits and the ratio was not correlated with Cobb’s angle. Conclusion: Thus, it can be concluded that patients with idiopathic scoliosis show reduced lung volumes and capacity on PFT and the pulmonary parameters show strong inverse correlation with the severity of the spinal deformity (Cobb’s angle).

Periostin as a biomarker for the diagnosis of pediatric asthma.

There are some biomarkers for asthma diagnosis but they are often difficult in clinical use, particularly in pediatric cases. Periostin is an extracellular matrix protein, upregulated in response to IL-4 or IL-13. Serum periostin is expected to be used as a non-invasive biomarker for asthma diagnosis and management. Twenty-eight children with asthma (BA) and 27 children without asthma (patients with pectus excavatum, etc. as control group) aged 6-16 years were included. Bronchial asthma was diagnosed according to International Study of Asthma and Allergies in Childhood (ISAAC) questionnaire. Fractional exhaled nitric oxide (FeNO), lung function, blood eosinophil counts, total immunoglobulin E (IgE) levels, and serum periostin levels were assessed. Results were compared between BA and controls. Asthma diagnostic accuracies were calculated using receiver operating characteristics (ROC) curve analyses. Serum periostin levels in the BA group were significantly higher than those in the control group [medians (with interquartile ranges), 134.0 (116.3-166.3) vs. 112.0 (97.0-132.0) ng/ml; p = 0.012]. The area under the ROC curve (AUC) for periostin, FeNO, and eosinophil counts were 0.70, 0.72, and 0.84, respectively. After the exclusion of controls with pectus excavatum, AUC for periostin, forced expiratory volume in 1 s (FEV1 ), and maximum mid-expiratory flow rate (MMF) were 0.75, 0.74, and 0.80, respectively. Serum periostin levels were significantly higher in children with asthma. ROC AUC values for periostin were equivalent to conventional biomarkers, including FeNO levels and lung function testing, indicating the utility of serum periostin levels in diagnosing asthma in children.