Maximal Expiratory Flow Rates Research Articles

The impact of strategic napping on peak expiratory flow and respiratory function in young elite athletes

Respiratory health is a critical determinant of athletic performance, and the utilization of restorative strategies, such as strategic napping, may offer a competitive edge to athletes. This study investigates the effects of nap duration on the respiratory function of young elite athletes who have achieved top rankings national competitions. Participants engage in three test sessions with varying nap durations: no nap (N0), a 25-minute nap (N25), and a 45-minute nap (N45), with a minimum 72-hour interval between sessions. Respiratory parameters including Forced Vital Capacity (FVC), Forced Expiratory Volume in one second (FEV1), FEV1/FVC ratio, Peak Expiratory Flow rate (PEF), Forced Expiratory Flow at 25–75% of FVC (FEF25-75%), and Forced Expiratory Time (FET) are assessed. Results reveal a significant enhancement in PEF values following a 45-minute nap (N45) compared to the no-nap control (N0) [F1 − 11=7.356, p =.004, ηp2 = 0.401, (95% CI for difference: -1.56 to − 0.056)], indicating a potential positive influence of napping on maximum expiratory flow rate and, consequently, athletes’ respiratory performance. While no significant changes are observed in other respiratory parameters across different nap durations, these findings underscore the potential benefits of strategic napping in optimizing respiratory health in young elite athletes.

Exercise-Induced Bronchoconstriction in Children: A Comparison between Athletes and Non-Athletes.

Exercise-induced bronchoconstriction (EIB) is a dysfunction of the respiratory tract consisting of transient airflow obstruction. This study is a retrospective analysis of two prospective studies concerning EIB symptoms in two adolescent populations. Our study group included 400 non-athletes and 101 athletes. Due to the similarity of indoor exercise conditions, an analysis was performed on the basis of where training took place. The study aims to assess the EIB prevalence in the following groups of adolescent children: non-athletes and athletes. In "indoor" athletes, the EIB prevalence was 22.4%. Among non-athletes, EIB was diagnosed in 10.2% (p = 0.007). A history of asthma was found in 6.5% of non-athletes and 29.3% of indoor athletes (p < 0.001). The incidence of EIB without asthma was higher in indoor athletes (14.6%) than in non-athletes (9.9%). Athletes achieved higher mean values in forced expiratory volume in one second (FEV1), forced vital capacity (FVC), peak expiratory flow (PEF), and maximum expiratory flow rate at 25% (MEF25) parameters. In the group of non-athletes, higher results were observed in forced expiratory volume in one second % of vital capacity (FEV1%VC), MEF50, and MEF75. The findings of the study present the complexity of the EIB diagnosis among children training in an indoor environment.

What adverse health effects will environmental heavy metal co-exposure bring us: based on a biological monitoring study of sanitation workers.

To investigate the relationship between health effect profile and co-exposure to heavy metal, 254 sanitation workers from Guangzhou, China, were recruited. Ten urinary metals were determined by inductively coupled plasma mass spectrometry. Parameters of physical examination, including blood lipid metabolism, renal function, blood pressure, and lung function, were tested for each participant. The hazard quotients (HQs) of eight heavy metals were evaluated. Cobalt, copper (Cu), molybdenum (Mo), nickel (Ni), and tin (Sn) demonstrated the top five associations with human health with the ∑19β as 2.220, 1.351, 1.234, 0.957, and 0.930, respectively. Most physical examination parameters of workers were under the normal ranges, except the levels of forced mid expiratory flow rate (MMEF75/25), the maximum expiratory flow rate at 25% vital capacity (MEF25) and apolipoprotein B in the first quartile, and the level of uric acid in the third quartile of sanitation works. Moreover, Cu was significantly associated with diastolic pressure, pulse, and high density lipid (p < 0.05). Each unit increase in Mo level was related to a 120% increase odd ratio (OR) of abnormal of systolic pressure, but was significantly and negatively correlated with high density lipoprotein and apolipoprotein A, suggesting that Mo exposure may be a risk factor of cardiovascular disease. Each unit increase in Ni and Sn levels was associated with an increased OR of abnormal rate of MMEF75/25 and MEF25 (p < 0.001), suggesting the increasing risks of respiratory diseases. Sanitation workers exposed to Ni and Pb alone had no carcinogenic risks (HQ < 1). However, 23.8%, 34.6%, and 87.3% of sanitation workers confronted non-carcinogenic risks when exposed to Cu, Mo alone (HQ > 1), or co-exposed to the four heavy metals (HI > 1). Our study preliminarily revealed the potential sensitive health indicators of heavy metal co-exposure, which will provide beneficial health protection suggestions for the occupational populations.

ВЗАИМОСВЯЗЬ ОБМЕНА ФОСФАТОВ И ФУНКЦИИ ВНЕШНЕГО ДЫХАНИЯ У ДЕТЕЙ И ПОДРОСТКОВ С БРОНХИАЛЬНОЙ АСТМОЙ

Objective of the study: to study some indicators of renal function, phosphate homeostasis and their relationship with external respiration function parameters in children and adolescents with bronchial asthma (BA). Materials and methods of research: a pilot prospective non-randomized single-center comparative study of 31 children aged 12.0 [9.0; 14.0] years with atopic BA. All children underwent anthropometry, spirometry, blood biochemical parameters test and 24-hour urine collection. Results: glomerular filtration rate calculated by the classic Schwartz formula was below the median in 18 (58%) of 31 patients. Serum phosphate concentration was excessive (more than +1Z above the mean) in 71% (22/31) of patients. Positive relationships were found between the maximum expiratory flow rate at the 25% point of the flow–volume loop (MOC25), the average expiratory flow rate at the 25–75% portion of the flow–volume loop (COC25–75), and blood creatinine concentration (r=0.36, p=0.04 and r=0.34, p=0.05, respectively); a negative relationship between the ratio of forced expiratory volume in 1 s to forced vital capacity and urinary phosphate concentration (r=–0.38, p=0.03). A negative relationship was noted between MOC25, SOC25–75 and urinary phosphate concentration (r=–0.37, p=0.03 and r=–0.36, p=0.04, respectively) and phosphorus/creatinine ratio (r=–0.4, p=0.02 and r=–0.39, p=0.02, respectively). Agedependent sex differences normalized phosphate excretion was positively correlated with MOC25 (r=0.36, p=0.04). Conclusion: we have found a negative relationship between the concentration of phosphates in urine and blood with indicators of bronchial patency, as well as a positive relationship between patency in the small bronchi and the concentration of blood creatinine. The development of phosphate metabolism disorders in patients with BA may be associated with prolonged spasm of bronchial smooth muscles with the development of hyperphosphatemia and compensatory hyperphosphaturia. Further study of glomerular and tubular function in children with BA is required for the purpose of early prevention of the development of chronic kidney disease in this cohort.

Effect of age, gender, and body mass index on peak expiratory flow rate and other pulmonary function tests in healthy individuals in the age group 18-60 years

Background: Normal ageing and increasing body mass index (BMI) are related to decline in lung functions in adults in both genders. Females are more likely than age and height-matched males to show smaller lung size and diffusion surface, lower maximal expiratory flow rate, and reduced airway diameter. Lung mechanics and respiratory muscle strength, thoracic compliance, airway resistance, and elastic recoil of the lungs determine the pulmonary function tests (PFTs), and these tests are known to differ with age, sex, socio-economic status, cultural factors, and geographical region of the subject and are related to weight, height and BMI of the individuals. Aim and Objectives: The present study is planned to assess the peak expiratory flow rate (PEFR) and other PFTs and to evaluate the effect of age, gender and BMI on these lung functions. Materials and Methods: This study consists of 200 healthy individuals of age group 18–60 years. A sample was stratified into 5 age groups, and on the basis of BMI, the subjects were categorized as underweight, normal, overweight, and obese. Anthropometric measurements were recorded using standard procedures. PEFR was recorded using Wright’s peak-flow meter and forced vital capacity (FVC), Forced Expiratory Volume in 1 s (FEV1), FEV1/FVC, FEF25–75%, FEF2–1.2, slow vital capacity (SVC), and maximum voluntary ventilation (MVV) were analyzed using Expirograph (Helios 401, RMS, India). Chi-square test was used for analysis of categorical variables. For comparison of two groups, unpaired t-test was used and to assess the relation between the variables, Pearson’s co-relation was used. One way ANOVA was used to compare the difference between the means of more than two groups and Tukey post hoc analysis was done for multiple comparisons. Results: There was highly significant difference in the mean values of PEFR and other PFTs (P < 0.000) among the 5 age groups and a significant difference between younger and older age groups. PEFR, FVC, FEV1, FEV1/FVC, FEF25–75%, FEF0.2–1.2, SVC, and MVV were negatively correlated with age (r = −0.514, −0.535, −0.568, −0.255, −0.566, −0.516, −0.304, −0.523, respectively). Females showed reduced mean values of PEFR, FVC, FEV1, FEF25–75%, FEF0.2–1.2, SVC, MVV when compared to males (P < 0.000), and the differences in the mean values were significantly high. Highly significant difference was seen in the mean values of PEFR and other PFTs among the categories of BMI (P < 0.000). The mean values of FVC, FEV1, FEV1/FVC, FEF25–75%, FEF0.2–1.2, MVV were lower among underweight compared to their mean values among individuals with normal BMI. There was negative correlation between PEFR, FVC, FEV1, FEF25–75%, FEF0.2–1.2, SVC, MVV, and BMI (r = −0.327, −0.254, −0.238, −0.269, −0.254, −0.236, −0.195, respectively). Conclusions: PFTs aid in the prompt and accurate diagnosis of respiratory disorders, such as asthma, chronic obstructive pulmonary disease allowing for efficient management by encompassing a thorough understanding of the disease and exercise respiratory training regimens even in otherwise healthy individuals. The present study showed that PEFR and other PFTs decrease with advancing age and BMI and females showed reduced lung functions compared to males.

Changes and significance of autophagy in rat lung injury induced by gas explosion

Objective: To explore the changes and significance of autophagy in acute lung injury (ALI) induced by gas explosion in rats. Methods: In February 2018, the gas explosion in underground coal mine was simulated by large tunnel explosion experiment system, SD rats were randomly divided into control group and 6 distance groups (40 m, 80 m, 120 m, 160 m, 200 m, 240 m) with 18 rats in each group. The respiratory function of rats 24 h before and after explosion was detected. Post-explosion rats were anesthetized and sacrificed, histopathological changes of lung were observed by HE staining. Immunohistochemistry was performed to detect the in situ expression of autophagy marker protein microtubule-associated protein 1 light chain 3 (LC3B) . The expression levels of autophagy related gene 12 (Atg12) , LC3B, P62, lysosomal associated membrane protein 2 (Lamp2) , B-cell lymphoma/leukemia-2 (Bcl-2) and Bcl2 interaction protein (Beclin-1) were detected by Western blot. Results: After gas explosion, the rats in 80 m distance point group had the hightest mortality (n=13, 72.22%) and the most severe lung injury degree, and the histopathological scores was (4.00±0.00) point. After gas explosion, the minute ventilation volume (MVb) , maximum inspiratory flow rate (PIFb) and maximum expiratory flow rate (PEFb) of rats were lower than before the gas explosion (P<0.05) . The respiratory frequency of rats in 80 m, 200 m, and 240 m distance point groups were significantly higher than that in the control group (P<0.05) . The expression levels of LC3B in 40 m, 80 m, 120 m, 160 m, and 200 m distance point groups were higher than that in the control group (P<0.05) . The relative expression levels of Atg12 and LC3BⅡ/Ⅰ in lung tissues of rats in different distance point groups were higher than those in the control group (P<0.05) . The relative expression levels of Beclin1 in 40 m, 80 m, 120 m, and 160 m distance point groups were significantly higher than that in the control group (P<0.05) . The relative expression levels of P62 in 80 m, 160 m and 200 m distance point groups were lower than that in the control group (P<0.05) . The relative expression levels of Lamp2 and Bcl-2 in lung tissues of rats in all distance groups except 240 m distance group were lower than those in the control group (P<0.05) . Conclusion: Gas explosion could induce increased autophagy in lung tissues of ALI rats. Autophagy-related signaling pathway could be involved in the pathophysiological process of ALI in rats caused by gas explosion, then the autophagy and the severity of the lesion showed a significant positive correlation.

Effects of Endoscopic Sinus Surgery for Eosinophilic Chronic Rhinosinusitis on Respiratory Functions and FeNO Production in the Lower Respiratory Tract.

To confirm the relevance of upper and lower airway inflammation in eosinophilic chronic rhinosinusitis (ECRS), the effects of endoscopic sinus surgery (ESS) on lower airway functions and inflammation need to be examined in ECRS patients. Chronic rhinosinusitis patients with nasal polyps (25 non-ECRS, 28 ECRS) were enrolled. The 12 patients in the ECRS group had comorbid asthma, in contrast to none in the non-ECRS group. We divided ECRS patients into 2 groups of ECRS with and without asthma. Clinical markers, including fraction of exhaled nitric oxide (FeNO), respiratory functions, and the Asthma Control Test (ACT) questionnaire, were investigated before and after ESS. The FeNO levels in the ECRS with asthma group decreased after ESS. The mean FeNO levels in this group were 56.3 ppb before ESS and 24.9, 25.1, 25.0, and 15.5 ppb 1, 2, 3, and 4 months, respectively, after ESS. The mean forced expiratory rates in 1 second before and after ESS were 67.6% and 73.0%, respectively. The mean maximal expiratory flow rates at 50% of the vital capacity before and after ESS were 45.8% and 58.0%, respectively. Significant differences were observed in respiratory functions before and after ESS. The mean ACT scores in the ECRS with asthma group before and after ESS were 17.5 and 23.5, respectively. The ACT scores were significantly higher after than before ESS. The present results indicate that ECRS and bronchial asthma are common eosinophilic airway inflammatory diseases, and ESS for eosinophilic sinusitis may improve lower airway function.

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.

Abstract 16698: Cardiopulmonary Exercise Testing With an In-Line Filter During the COVID-19 Pandemic

Introduction: During maximum incremental exercise expiratory flow rates increase &gt; 10-fold and minute ventilation can exceed 100L/min, raising concern for possible spread of COVID-19 in asymptomatic patients undergoing exercise testing. Moreover, use of surgical or N95 masks that limit airflow are recognized to limit the ability to perform maximum exercise. Hypothesis: Use of an in-line filter during cardiopulmonary exercise testing is feasible and will not adversely impact measurements of exercise capacity. Methods: We conducted a proof-of-principle study in which a commercially available electrostat filter (Figure 1A), which has &gt;99.9% viral efficiency without affecting spirometry measurements during pulmonary function testing, was placed in-line, upstream of the flow meter and gas analyzer sample line for use during cardiopulmonary exercise testing. A single healthy subject completed incremental exercise with a 3 min period of unloaded exercise followed by 4-min stages of exercise at 50, 100, 150, and 200W with and without the filter in place on the same day. Mechanical dead space was 53 ml with the filter and 45 ml without. Results: In comparison to no internal filter, use of an in-line filter resulted in VO 2 measurements of 99%, 97%, 98%, and 97% during 50W, 100W, 150W, and 200W, respectively (Figure 1A). VO 2 /work slope measurements and measurements of minute ventilation were also highly consistent throughout exercise with and without use of an in-line filter (Figure 1B). Conclusions: Exercise testing is an integral part of cardiovascular care delivery. Our findings require further validation but suggest that an in-line filtration system can be utilized in an effort to reduce droplet and viral dissemination without impacting measures of cardiopulmonary performance.

Calprotectin as a New Sensitive Marker of Neutrophilic Inflammation in Patients with Bronchiolitis Obliterans.

Introduction Bronchiolitis obliterans (BO) is a chronic disease in which persistent inflammation leads to obstruction and obliteration of the small airways. The aim of this study was to evaluate the value of calprotectin as an inflammatory marker in induced sputum. Methods Twenty-eight patients suffering from BO and 18 healthy controls were examined. Lung function was measured by spirometry, body plethysmography, and lung clearance index (LCI). The induced sputum was obtained, cell counts were performed, and cytokines were measured using cytometric bead array (CBA). Calprotectin was quantified in the sputum and serum samples using commercially available sandwich ELISA. Results Spirometry parameters including forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), and maximum expiratory flow rate at 25% vital capacity (MEF25) were significantly lower in BO patients than in healthy controls, whereas the reserve volume (RV), RV to total lung capacity ratio (RV/TLC), and LCI were significantly increased. In sputum, calprotectin levels, neutrophils, and IL-8 were significantly elevated. Calprotectin levels correlated strongly with IL-8 and other biomarkers, neutrophils FEV1 and MEF25. In serum, calprotectin was significantly diminished in BO patients compared to controls. Conclusion Lung function is severely impaired in BO patients. Calprotectin is significantly elevated in the sputum of BO patients and reflects ongoing neutrophilic inflammation.

Differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia

Objective: To investigate the differences in small airway lesions in patients with different types of idiopathic interstitial pneumonia (IIPs). Methods: A total of 46 patients with IIPs confirmed by video assisted thoracoscopic or open lung biopsy, hospitalized in the Respiratory and Critical Care Medicine of Beijing Chao-Yang Hospital, from Dec. 1998 through Nov. 2007 were studied, including 19 patients with idiopathic pulmonary fibrosis (IPF group), 14 with nonspecific interstitial pneumonia (NSIP group), and 13 cryptogenic organizing pneumonia (COP group). Pulmonary function and high resolution CT (HRCT) of the patients were examined before lung biopsy, and lung biopsy tissue were stained with hematoxylin-eosin. The abnormality of small airways in pathology, pulmonary function and HRCT were compared among these patients with IIPs. Results: Small airway inflammatory cell infiltration score (53.8±17.7) was significantly higher in the COP group than in the IPF group (38.8±9.7) (P<0.01). The fibrous tissue proliferation score in small airways (42.9±12.1) in the IPF group was significantly higher than that in the NSIP group (31.4±10.5) and the COP group (26.7±16.3) (both P<0.05). In the IPF group, NSIP group and COP group, the small airway function index was significantly reduced, and the maximum expiratory flow rate (V(25%), V(50%)) at 25% and 50% of the lung capacity was<80% predicted, the incidences of small airway dysfunction in the three groups were 63.2%, 69.2%, and 63.6%, respectively. There was no significant difference among the groups (P>0.05). Small airway inflammatory cell infiltration was negatively correlated with V(50%) of small airway function (r=-0.305, P=0.049). The bronchodilation rate in the HRCT of the IPF group (100%) was significantly higher than that of the NSIP group (50.0%) and the COP group (53.8%) (both P<0.01). Conclusion: The patients with IPF, NSIP and COP have abnormal pathologic, physiological and imaging changes of small airways, moreover have different characteristics.

Design and Implementation of Digital Asthma Diagnosis System

In this article, the MSP430F149 is the microcontroller (MCU), and a pressure sensor, MPX5100AP, is used to measure body measurement of maximal forced expiratory volume (FEV) and peak expiratory flow rate (PEFR). The two analog signals are processed by the signal conditioning circuit, and then the corresponding digital signals are acquired by the MCU. With the related operations of multiple respiratory parameters, a built-up time of respiration signal mutation rate values and the determination of the mutation rate, a mathematical model is built among FEV, PEFR and the rate of variation. The mathematical model of the system is analyzed, and the relationship between the detection results and the degree of airway obstruction is established. Finally, the patient's condition analysis results are given directly on the LCD, which provided the objective indicators for the medical treatment of the disease.

Effect of EMG-biofeedback robotic-assisted body weight supported treadmill training on walking ability and cardiopulmonary function on people with subacute spinal cord injuries \u2013 a randomized controlled trial

BackgroundBody weight supported treadmill training (BWSTT) is a frequently used approach for restoring the ability to walk after spinal cord injury (SCI). However, the duration of BWSTT is usually limited by fatigue of the therapists and patients. Robotic-assisted body weight supported treadmill training (RABWSTT) was developed to tackle the aforesaid limitation. Currently, limited randomized controlled trials are available to investigate its effectiveness, especially on cardiopulmonary function. The aim of this two-arm, parallel-group randomized controlled trial is to examine the feasibility of adapting an EMG-biofeedback system for assist-as-needed RABWSTT and its effects on walking and cardiopulmonary function in people with SCI.MethodsSixteen incomplete SCI subjects were recruited and randomly allocated into an intervention group or control group. The intervention group received 30 min of RABWSTT with EMG biofeedback system over the vastus lateralis muscle to enhance active participation. Dose equivalent passive lower limbs mobilization exercise was provided to subjects in the control group.ResultsSignificant time-group interaction was found in the Walking Index for Spinal Cord Injury version II (WISCI II) (p = 0.020), Spinal Cord Independence Measure version III (SCIM III) mobility sub-score (p < 0.001), bilateral symmetry (p = 0.048), maximal oxygen consumption (p = 0.014) and peak expiratory flow rate (p = 0.048). Wilcoxon signed-rank test showed that the intervention group had significant improvement in the above-mentioned outcomes after the intervention except WISCI II, which also yielded marginal significance level.ConclusionThe present study demonstrated that the use of EMG-biofeedback RABWSTT enhanced the walking performance for SCI subjects and improve cardiopulmonary function. Positive outcomes reflect that RABSTT training may be able to enhance their physical fitness.Trial registrationThe study protocol was approved by the Research Ethics Committee (Kowloon Central/ Kowloon East), Hospital Authority on 6 December 2013, and the Human Subjects Ethics Sub-committee of The Hong Kong Polytechnic University on 15 May 2013, with reference numbers KC/KC-13-0181/ER-2 and HSEARS20130510002 respectively. The study was registered in ClinicalTrials.gov on 20 November 2013, with reference number NCT01989806.)

Exploring physiological parameters in ski mountaineering during world cup races

ABSTRACTThe aim of this study was to explore the physiological changes induced by a vertical race and see how they are progressing the next day during individual race. A total of 10 elite skiers (19.4 ± 2.4 years) were evaluated before and after a vertical race and an individual race during a week end of World Cup. The parameters measured were as follows: heart rate, lactate, lung function by spirometry and body composition by bioelectrical impedance. During vertical race, mean heart rate (HR) values were around 93.1 ± 3.1% of theoretical HRmax. Before individual race, lactate concentration was significantly higher (+1.0 ± 1.6 mmol.l−1), whereas mid maximal expiratory flow rate and muscle mass (fall was around 700 g or 2.2% of muscle mass) were significantly lower compared to before vertical race. Metabolic activity indicator tended to be lower before individual race than before vertical race (6.8 ± 0.7 vs. 7.3 ± 1.3, p = 0.07). The high physiological demand of vertical race induces metabolic fatigue, loss of muscle mass and pulmonary impairment. Theses disturbances observed the next day before individual race indicate an incomplete recovery between the two races. That is why we recommend using method of recovery, especially nutritional strategy after vertical race.

Flow-Volume Curve Analysis for Predicting Recurrence After Endoscopic Dilation of Airway Stenosis

The flow-volume curve is a simple test for diagnosing upper airway obstruction. We evaluated its use to predict recurrence in patients undergoing endoscopic dilation for treatment of benign upper airway stenosis. The data of 89 consecutive patients undergoing endoscopic dilation of simple upper airway stenosis were retrospectively reviewed. Morphologic distortion of flow-volume loop (visual analysis) and quantitative criteria, including maximal expiratory flow rate at 50% of the vital capacity (MEF50%)/maximal inspiratory flow rate at 50% of the vital capacity (MIF50%) of less than 0.3 or more than 1.0, forced expiratory volume in 1 second/MEF exceeding 10, and forced expiratory volume in 1 second/forced expiratory volume in .05 second exceeding 1.5, were considered predictive of recurrence. In all cases, the recurrence was confirmed by radiologic or bronchoscopic findings, or both. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of visual, quantitative, and aggregate criteria for detecting recurrence were computed and compared. Of 89 patients treated, 27 (30%) had a recurrence. Visual analysis presented a sensitivity, specificity, PPV, NPV, and accuracy of 63%, 83.9%, 63%, 83.9%, and 77.5%, respectively. Among the quantitative criterion, the MEF50%/MIF50% was the most accurate, having a sensitivity, specificity, PPV, NPV, and accuracy of 77.8%, 79%, 61.8%, and 89.1%, and 78.7%, respectively. Aggregate criterion presented the best yield compared with other criteria in sensitivity (81.5%), specificity (91.9%), PPV (81.5%), NPV (91.9%), and accuracy (88.8%). The flow-volume curve is a simple and noninvasive method to monitor patients undergoing endoscopic dilation of upper airway stenosis. Morphologic changes in the flow-volume loop and in the MEF50%/MIF50% ratio are suggestive of recurrence and guide the physician to implement the follow-up with further diagnostic (non)invasive examinations.

Differential Effects of Inspiratory Muscle Training Between Athletes and Performing Artists

The purpose of this study was to examine whether inspiratory muscle training (IMT) had differential effects between athletes and performing artist's diaphragm performance. It was hypothesized that the performing artists would experience greater improvements in diaphragm performance than the athletes following an IMT program. The two groups underwent IMT by breathing through an IMT device 2 times every day for 9–11 weeks at 50% of their maximal inspiratory pressure (IP) for 30 seconds. Following IMT there was a significant increase (p&lt;0.05) in maximal IP for athletes (2.7 mmHg or a 24% increase) and performing artists (5.8 mmHg or a 28.5% increase) compared to the control group (1.8 mmHg or a 13.1% increase). No significant difference in maximal expiratory flow rate (EFR) was observed between the groups or compared to controls. While athletes and performing artists both experienced significant improvements in diaphragm performance following the IMT program compared to the control group, no significant difference was observed between the groups for their percent change in IP or EFR. These results show that the magnitude of the effect of the IMT program between athletes and performing artists was equal. The data suggests that performing artists' diaphragm performance responds similarly to athletes' following a IMT program, which is likely due to regular use of their respiratory muscles when practicing for performancesThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The effect of ventilator mask atomization inhalation of ipratropium bromide and budesonide suspension liquid in the treatment of COPD in acute exacerbation period on circulating levels of inflammation and prognosis.

We investigated the effects of ventilator mask atomization inhalation of ipratropium bromide and budesonide suspension liquid in the treatment of acute exacerbation COPD (AECOPD) on circulating levels of inflammatory factors and prognosis. A total of 86 cases of patients on ventilator support were randomly divided into control group and observation group with 43 cases each. The control group was administered routine treatment including basic disease treatment, anti-infection, maintenance of a stable internal environment, nutritional support, oxygen inhalation and so on. The control group was administered saline through a ventilator mask. The observation group was treated with atomized inhalation of ipratropium bromide and budesonide suspension and oxygen flow 3-5 L/min, 15-20 min/time and twice a day for 1 week. The treatment effects were compared. Serum TNF-α, IL-6, and CRP levels were decreased in both groups after treatment, but levels in the observation group were significantly lower than those of the control group; differences were statistically significant (p < 0.05). Forced vital capacity (FVC), forced expiratory volume (FEV1), FEV1/FVC and maximal expiratory flow rate in the observation group were significantly higher than those in the control group after treatment (p < 0.05). After treatment, the PaO2, SpO2 and respiratory failure index (RFI) of the observation group were significantly higher than those of the control group. The PaCO2 levels of the observation group were lower than those of the control group. The differences were statistically significant (p < 0.05). The clinical efficacy of the observation group was better than that of the control group; the ventilation time and total treatment time was significantly shorter and the differences were statistically significant (p < 0.05). The ventilator mask atomizing inhalation of ipratropium bromide and budesonide suspension liquid in the treatment of AECOPD can significantly improve circulating inflammatory reaction, improve lung function and blood gas levels, increase the treatment efficiency, and shorten the treatment time.

The relationship between lung function and the clinical and histopathological features in Chinese patients with nasal polyps.

To investigate lung function in Chinese patients suffering from chronic rhinosinusitis with nasal polyps and examine its association with histopathological features. The lung function of 99 patients with nasal polyps was measured. Haematoxylin and eosin and immunohistochemistry staining were performed to evaluate any inflammatory cells and epithelial tissue remodelling. Predicted maximal expiratory flow rate at 25 per cent vital capacity was reduced (p < 0.05) in epithelial hyperplasia, and predicted maximal expiratory flow rate at 50 per cent vital capacity was reduced (p < 0.05) in goblet cell hyperplasia. Both peripheral blood eosinophilia and tissue eosinophilia nasal polyps manifested significantly reduced: forced expiratory volume in 1 second/forced vital capacity ratio, predicted maximal expiratory flow rate at 25, 50 and 75 per cent of vital capacity, and predicted maximal mid-expiratory flow. Peripheral blood eosinophils were negatively correlated with predicted maximal expiratory flow rate at 25 and 50 per cent of vital capacity, and predicted maximal mid-expiratory flow. Eosinophils in tissue were negatively correlated with all lung function parameters investigated except predicted forced vital capacity. Clinicians should be aware of lung function decline in nasal polyps patients, especially in those with tissue eosinophilia.

Segmental bronchi collapsibility: computed tomography-based quantification in patients with chronic obstructive pulmonary disease and correlation with emphysema phenotype, corresponding lung volume changes and clinical parameters.

Global pulmonary function tests lack region specific differentiation that might influence therapy in severe chronic obstructive pulmonary disease (COPD) patients. Therefore, the aim of this work was to assess the degree of expiratory 3rd generation bronchial lumen collapsibility in patients with severe COPD using chest-computed tomography (CT), to evaluate emphysema-phenotype, lobar volumes and correlate results with pulmonary function tests. Thin-slice chest-CTs acquired at end-inspiration & end-expiration in 42 COPD GOLD IV patients (19 females, median-age: 65.9 y) from November 2011 to July 2014 were re-evaluated. The cross-sectional area of all segmental bronchi was measured 5 mm below the bronchial origin in both examinations. Lung lobes were semi-automatically segmented, volumes calculated at end-inspiratory and end-expiratory phase and visually defined emphysema-phenotypes defined. Results of CT densitometry were compared with lung functional tests including forced expiratory volume at 1 s (FEV1), total lung capacity (TLC), vital capacity (VC), residual volume (RV), diffusion capacity parameters and the maximal expiratory flow rates (MEFs). Mean expiratory bronchial collapse was 31%, stronger in lobes with homogenous (38.5%) vs. heterogeneous emphysema-phenotype (27.8%, P=0.014). The mean lobar expiratory volume reduction was comparable in both emphysema-phenotypes (volume reduction 18.6%±8.3% in homogenous vs. 17.6%±16.5% in heterogeneous phenotype). The degree of bronchial lumen collapsibility, did not correlate with expiratory volume reduction. MEF25 correlated weakly with 3rd generation airway collapsibility (r=0.339, P=0.03). All patients showed a concentric expiratory reduction of bronchial cross-sectional area. Changes in collapsibility of 3rd generation bronchi in COPD grade IV patients is significantly lower than that in the trachea and the main bronchi. Collapsibility did not correlate with the reduction in lung volume but was significantly higher in lobes with homogeneous vs. heterogeneous emphysema phenotype. Changes in the 3rd generation bronchial calibres between inspiration and expiration are not predictive for the degree of small airway collapsibility and related airflow limitation.

Step-down therapy in well-controlled asthmatic patients using salmeterol xinafoate/fluticasone propionate combination therapy.

PurposeA combination therapy with inhaled corticosteroid (ICS) and a long-acting β agonist (LABA) is the standard treatment for asthmatic patients, and step-down treatment is recommended once control has been achieved. However, little data exist that evaluate the long-term outcomes after step-down treatment.ObjectiveTo compare the long-term outcomes of step-down therapy with ICS/LABA or ICS alone for asthmatic patients who have achieved well-controlled asthma by the ICS (250 µg fluticasone)/LABA (50 µg salmeterol) combination (SFC, two puffs per day).Patients and methodsWe randomized 40 well-controlled patients with asthma receiving SFC (250 µg) to two groups; one group of patients received step-down therapy with low-dose SFC (100 µg, two puffs daily) and another group of patients received step-down therapy with high-dose fluticasone propionate (FP) alone (500 µg, daily). The two groups were monitored over 12 months for changes in asthma control test scores, respiratory function (percent forced expiratory volume in 1 second, maximal expiratory flow rate at 50% of the vital capacity [%FEF50], and maximal expiratory flow rate at 25% of the vital capacity [%FEF25]), and the concentration of fractional exhaled nitric oxide.ResultsThere was no significant difference in the dropout rate between the SFC and FP groups. Low-dose SFC maintained the stability of all parameters over 12 months, whereas the FP group exhibited a rapid 5% decrease in forced expiratory volume in 1 second within 2 months after discontinuation of salmeterol; furthermore, after 10 months, there was a gradual decrease in %FEF50 and %FEF25.ConclusionThis study suggests that a balanced step-down protocol, including both ICS and LABA, is essential in providing long-term stability to patients with mild-to-moderate well-controlled asthma.