Reference Equations for Within-Breath Respiratory Oscillometry in White Adults.

BACKGROUND: Within-breath analysis of oscillometry parameters is a growing research area since it increases sensitivity and specificity to respiratory pathologies and conditions. However, reference equations for these parameters in White adults are lacking and devices using multiple sinusoids or pseudorandom forcing stimuli have been underrepresented in previous studies deriving reference equations. The current study aimed to establish reference ranges for oscillometry parameters, including also the within-breath ones in White adults using multi-sinusoidal oscillations. METHODS: White adults with normal spirometry, BMI ≤30 kg/m2, without a smoking history, respiratory symptoms, pulmonary or cardiac disease, neurological or neuromuscular disorders, and respiratory tract infections in the previous 4 weeks were eligible for the study. Study subjects underwent oscillometry (multifrequency waveform at 5-11-19 Hz, Resmon PRO FULL, RESTECH Srl, Italy) in 5 centers in Europe and the USA according to international standards. The within-breath and total resistance (R) and reactance (X), the resonance frequency, the area under the X curve, the frequency dependence of R (R5-19), and within-breath changes of X (ΔX) were submitted to lambda-mu-sigma models for deriving reference equations. For each output parameter, an AIC-based stepwise input variable selection procedure was applied. RESULTS: A total of 144 subjects (age 20.8-86.3 years; height 146-193 cm; BMI 17.42-29.98 kg/m2; 56% females) were included. We derived reference equations for 29 oscillatory parameters. Predicted values for inspiratory and expiratory parameters were similar, while differences were observed for their limits of normality. CONCLUSIONS: We derived reference equations with narrow confidence intervals for within-breath and whole-breath oscillatory parameters for White adults.

The rationale of applying inspiratory/expiratory muscle training within the same respiratory cycle in children with bronchial asthma: a placebo-controlled randomized clinical investigation.

OBJECTIVE: Even though positive implications of inspiratory muscle training (In-MT) have been established in children and adolescents with bronchial asthma (C/AwBA), the role of combined inspiratory and expiratory muscle training (Ex-MT) within the same respiratory cycle (In/Ex-SC) is still unknown. This study was, therefore, set out to explore the effect of In/Ex-SC on respiratory muscle strength, pulmonary functions, and control of asthma symptoms in C/AwBA. METHODS: This was a placebo-controlled randomized clinical investigation that included 51 C/AwBA (12-18 years). Participants were assigned randomly into three groups: Placebo, In-MT only, or combined In/Ex-SC training (n = 17, each group). The training was conducted for ∼35 min, thrice/week over 12 weeks. The maximal inspiratory (IPmax) and expiratory (EPmax) pressure (indicating the strength of the inspiratory and expiratory muscles, respectively), pulmonary functions [forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC index], and asthma control test (ACT) were assessed before and after the intervention. RESULTS: The In/Ex-SC yielded larger increases in IPmax and EPmax than either the Placebo training (P=.031 and P=.009 respectively) or the In-MT (P=.029 and P=.032 respectively). Further, In/Ex-SC produced favorable improvement in FEV1, FVC, and FEV1/FVC compared to the Placebo training (P=.001, P=.004, and P=.0005 respectively) or In-MT (P=.038, P=.037, and P=.025 respectively) training. Furthermore, In/Ex-SC led to better control of asthma symptoms than the Placebo (P<.001) or In-MT (P=.002) training. CONCLUSION: This study provides evidence that combined In/Ex-SC can considerably improve respiratory muscle strength, enhance pulmonary function, and promote control over asthma symptoms in C/AwBA.

Demographic and clinical characteristics of newborn pneumothorax patients and their effects on respiratory function tests during childhood.

PURPOSE: Pneumothorax is defined as the presence of air between the parietal and visceral leaves of the pleura, resulting in lung collapse. The aim of this study was to evaluate the respiratory functions of these patients when they reach school age and to reveal whether they cause permanent respiratory pathology. METHODS: The files of 229 patients who were hospitalised in a neonatal intensive care clinic had received a diagnosis of pneumothorax and had undergone tube thoracostomy were included in a retrospective cohort review. The respiratory functions of participants in the control and patient groups were evaluated using spirometry in a prospective cross-sectional study design. RESULTS: The study found the rates of pneumothorax to be higher in males, term infants and after caesarean delivery, mortality was 31%. Among patients who underwent spirometry, those with a history of pneumothorax had lower forced expiratory volume at timed intervals of 0.5 to 1.0 (FEV1), forced vital capacity (FVC), FEV1/FVC, peak expiratory flow (PEF) and forced expiratory flow 25-75% (MEF25-75). FEV1/FVC ratio was significantly lower (p < 0.05). CONCLUSION: Patients treated for pneumothorax in the neonatal period should be evaluated for obstructive pulmonary diseases during childhood using respiratory function tests.

Long-term clinical course and outcomes in patients with lymphangioleiomyomatosis.

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a rare multisystemic disorder with various clinical manifestations. Despite the recognition of several prognostic factors, the long-term clinical course and prognosis of patients with LAM in the era of sirolimus therapy are not established. METHODS: The clinical data of 104 patients with LAM were retrospectively analyzed. Death or lung transplantation was defined as the primary outcome. Disease progression (DP) was defined as a 10% absolute decline in forced expiratory volume in one second (FEV1). RESULTS: The mean age of all patients was 40.3 years. Over a median follow-up period of 7.1 years, of all patients, 6.7% died and 1.9% underwent lung transplantation, while of 92 patients with serial lung function data, 35.9% experienced DP. The 5-year and 10-year overall survival rates were 93.0% and 90.9%, respectively. The multivariable Cox analysis revealed that older age (hazard ratio [HR]: 1.136, P = 0.025), lower FEV1 (HR: 0.956, P = 0.026) or diffusing capacity for carbon monoxide (HR: 0.914, P = 0.003), and shorter distance during the 6-min walk test (HR: 0.993, P = 0.020) were independent prognostic factors for mortality. A propensity score-matched comparative analysis performed between patients who received sirolimus therapy and those who did not, found no differences in survival, DP, complications, and lung function decline rate. CONCLUSIONS: Over a follow-up period of approximately 7 years, one-tenth of all patients experienced death, while one-third experienced DP. Older age, lower lung function, and reduced exercise capacity were associated with a poor prognosis in patients with LAM.

Associations of physical condition with lung function and asthma in adolescents from the general population.

BACKGROUND: The relation of physical condition with respiratory outcomes in adolescents is unclear. We examined the hypothesis that adolescents with a lower physical condition represented by a lower cardiorespiratory fitness and physical activity, and a higher screen time have a lower lung function and higher risk of asthma. METHODS: In a population-based prospective cohort study on 4854 children aged 13 years, we assessed cardiorespiratory fitness by using the peak work rate measured by the steep ramp test. Information on physical activity and screen time was obtained by self-reported questionnaires. Lung function was measured by spirometry and current asthma was assessed by a parental-reported questionnaire. RESULTS: Taking sociodemographic, lifestyle, and growth-related confounders and multiple hypothesis testing into account, a 1 SD lower cardiorespiratory fitness was associated with a lower FEV1 , FVC, and FEF75 (Z-score difference (95% CI): -0.31 (-0.35, -0.28), -0.30 (-0.33, -0.26), -0.13 (-0.17, -0.10), respectively), and a higher risk of asthma (Odds Ratio (95% CI) 1.25 (1.06, 1.46)). A 1 SD higher screen time was associated with a lower FVC (Z-score difference (95% CI): -0.06 (-0.10, -0.03)). Physical activity and screen time were not related to asthma. Results did not materially change after additional adjustment for respiratory outcomes at an earlier age. CONCLUSION: Adolescents with a lower cardiorespiratory fitness had a lower lung function and a higher risk of asthma. Those with a higher screen time had a lower FVC. Further studies are needed to explore the effect of improvements in physical condition on long-term respiratory outcomes.

Effects of a new respiratory muscle training device in community-dwelling elderly men: an open-label, randomized, non-inferiority trial.

BACKGROUND: Respiratory muscle training (RMT) has various clinical benefits in older adults; however, the low adherence to training remains a challenging issue. The present study aimed to confirm the efficacy of a new device that combines inspiratory muscle training and a positive expiratory pressure (IMT/PEP) compared to that of a Threshold IMT device (Philips Respironics Inc), and to determine whether home-based training differed from rehabilitation center training. METHODS: This four-arm, multicenter, parallel, non-inferiority trial randomized 80 active community-dwelling older men (mean age = 72.93 ± 5.02 years) to center-based groups (new IMT/PEP device or Threshold IMT device; 16 supervised sessions) or home-based groups (new IMT/PEP device or Threshold IMT device; 2 supervised sessions and individual sessions). Participants in all groups performed RMT twice a day for 8 weeks. Assessments were performed at baseline and post-training. The primary outcomes were maximum inspiratory pressure and maximal expiratory pressure. The secondary outcomes included forced vital capacity and forced expiratory volume in the first second, peak cough flow, diaphragm thickness, VO2 peak, the International Physical Activity Questionnaire score, electromyographic activities of the sternocleidomastoid muscle, and skeletal muscle mass and phase angle as measured by bioimpedance analysis. In addition, rates of adherence to each protocol were also compared. RESULTS: Among all groups, the maximal inspiratory pressure was improved post-training, while the maximal expiratory pressure showed improvement only in the IMT/PEP groups. The overall non-inferiority of the IMT/PEP device was thus validated. A statistically significant improvement in diaphragm thickness was found. However, no consistent improvement was shown in other secondary outcomes. No significant difference in training adherence rate between protocols was observed (mean adherence rate of 91-99%). CONCLUSION: Compared to the Threshold IMT, the new IMT/PEP device did not result in a significant difference in maximal inspiratory pressure but did improve maximal expiratory pressure in older men. The IMT/PEP device's improved usability, which is associated with exercise adherence, provided distinct advantages in this cohort. If proper education is first provided, home-based RMT alone may provide sufficient effects in older individuals. TRIAL REGISTRATION: This trial was registered in the database cris.nih.go.kr (registration number KCT0003901 ) on 10/05/2019.

Clinical predictors of lung function in patients recovering from mild COVID-19.

BACKGROUND: Few studies have assessed lung function in Hispanic subjects recovering from mild COVID-19. Therefore, we examined the prevalence of impaired pulmonary diffusing capacity for carbon monoxide (DLCO) as defined by values below the lower limit of normal (< LLN, < 5th percentile) or less than 80% of predicted in Hispanics recovering from mild COVID-19. We also examined the prevalence of a restrictive spirometric pattern as defined by the ratio of forced expiratory volume in 1 s (FEV1) to forced vital capacity (FVC) being ≥ LLN with the FVC being < LLN. Finally, we evaluated previous studies to find factors correlated to impaired DLCO post-COVID-19. METHODS: In this observational study, adult patients (n = 146) with mild COVID-19 were recruited from a long-term follow-up COVID-19 clinic in Yucatan, Mexico, between March and August 2021. Spirometry, DLCO, and self-reported signs/symptoms were recorded 34 ± 4 days after diagnosis. RESULTS: At post-evaluation, 20% and 30% of patients recovering from COVID-19 were classified as having a restrictive spirometric pattern and impaired DLCO, respectively; 13% had both. The most prevalent reported symptoms were fatigue (73%), a persistent cough (43%), shortness of breath (42%) and a blocked/runny nose (36%). Increased age and a restrictive spirometric pattern increased the probability of having an impaired DLCO while having a blocked nose and excessive sweating decreased the likelihood. The proportion of patients with previous mild COVID-19 and impaired DLCO increased by 13% when the definition of impaired DLCO was < 80% predicted instead of below the LLN. When comparing previous studies, having severe COVID-19 increased the proportion of those with impaired DLCO by 21% compared to those with mild COVID-19. CONCLUSIONS: One-third of patients with mild COVID-19 have impaired DLCO thirty-four days post-diagnosis. The criteria that define impaired DLCO and the severity of COVID-19 disease affects the proportion of those with impaired DLCO at follow-up. One-fifth of patients have a restrictive spirometric pattern.

Cardio-metabolic risk factors during childhood in relation to lung function and asthma.

BACKGROUND: Cardio-metabolic risk factors might have an adverse effect on respiratory outcomes, but associations in children are unknown. We aimed to study the longitudinal associations of cardio-metabolic risk factors with lung function and asthma at school age. We also examined whether any association was explained by child's body mass index (BMI). METHODS: In a population-based cohort study among 4988 children, cardio-metabolic risk factors were measured at 6 and 10 years and included blood pressure, cholesterol, triglycerides, insulin, and C-reactive protein (CRP) concentrations. At age 10 years, lung function was measured by spirometry and current physician-diagnosed asthma was assessed by questionnaire. RESULTS: After adjustment for confounders, child's BMI, and multiple testing, we observed that a higher diastolic blood pressure at the age of 6 years was associated with a higher forced vital capacity (FVC) at the age of 10 years (Z-score difference (95% CI): 0.05 (0.01, 0.08), per SDS increase in diastolic blood pressure). Also, child's CRP concentrations above the 75th percentile at both ages 6 and 10 years were related to a lower FVC as compared to CRP concentrations below the 75th percentile at both ages (Z-score difference (95% CI) -0.21 (-0.36, -0.06)). No consistent associations of other cardio-metabolic risk factors with respiratory outcomes were observed. CONCLUSION: Blood pressure and CRP, but not lipids and insulin, were associated with lower lung function but not with asthma. The underlying mechanisms and long-term effects of these associations require further investigation.

The influence of Epstein-Barr virus and cytomegalovirus on childhood respiratory health: A population-based prospective cohort study.

BACKGROUND: Epstein-Barr virus (EBV) and cytomegalovirus (CMV) infection are common in early childhood. CMV infection favours a T-helper-1 and EBV infection a T-helper-2 cell response, possibly leading to disbalanced T-helper cell response, and subsequent risk of asthma or atopy. OBJECTIVE: To study the associations of EBV and CMV with lung function, asthma and inhalant allergic sensitization at school age. METHODS: This study among 3546 children was embedded in a population-based prospective cohort. At age 6 years, serum IgG levels against EBV and CMV were measured by ELISA. At age 10 years, lung function was measured by spirometry, asthma by questionnaire and inhalant allergic sensitization by skin prick test. RESULTS: Unadjusted models showed that seropositivity for EBV was associated with a higher FEV1 and FEF75 (Z-score difference (95% CI): 0.09 (0.02, 0.16) and 0.09 (0.02, 0.15)), while seropositivity for CMV was not. Specific combinations of viruses showed that seropositivity for EBV was only associated with FEV1 and FEF75 in the presence of seropositivity for CMV (0.12 (0.04, 0.20)) and 0.08 (0.01, 0.15)). Seropositivity for CMV in the absence of seropositivity for EBV was associated with an increased risk of inhalant allergic sensitization (OR (95% CI): 1.31 (1.02, 1.68)). All effect estimates attenuated into non-significant mainly after adjustment for child's ethnicity. Seropositivity for EBV or CMV was not associated with asthma. CONCLUSIONS AND CLINICAL RELEVANCE: Associations of EBV and CMV infections in early childhood with school-age lung function and inhalant allergic sensitization are explained by ethnicity, or sociodemographic and lifestyle-related factors.

Computed tomography patterns predict clinical course of idiopathic pulmonary fibrosis.

BACKGROUND: A new clinical guideline for idiopathic pulmonary fibrosis (IPF) uses high-resolution computed tomography (HRCT) patterns for diagnostic purposes. However, it is unknown how they relate to the IPF clinical course. We aimed to investigate whether HRCT patterns could be used to predict lung function changes and survival in patients with IPF. METHODS: Clinical data were retrospectively reviewed in 337 patients with IPF (all biopsy-proven cases). HRCT patterns were classified according to the 2018 IPF diagnostic criteria. RESULTS: The median follow-up was 46.9 months. The mean age was 62.5 years, and 74.2% were men. Among the HRCT patterns, usual interstitial pneumonia (UIP), probable UIP, indeterminate for UIP, and an alternative diagnosis were identified in 163 (48.4%), 110 (32.6%), 33 (9.8%), and 31 (9.2%) patients, respectively. The indeterminate for UIP group showed higher lung function and exercise capacity and better prognosis than the other groups. They also had a lesser decline in lung function than the other groups during follow-up. In the multivariate Cox analysis, which was adjusted by age, smoking status, lung function, exercise capacity, and use of antifibrotic agents, indeterminate for UIP pattern was found to be an independent prognostic factor (hazard ratio 0.559, 95% confidence interval 0.335-0.933, P = 0.026). However, the probable UIP group had similar lung function changes and prognosis when compared the UIP group. CONCLUSIONS: Our results suggest that indeterminate for UIP pattern on HRCT may predict a more favorable clinical course in patients with IPF, supporting the validity of the new IPF diagnostic guidelines.

Airway bacterial carriage and childhood respiratory health: A population-based prospective cohort study.

BACKGROUND: Airway bacterial carriage might play a role in respiratory disease. We hypothesize that nasal carriage with Staphylococcus aureus or nasopharyngeal carriage with Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus pneumoniae predisposes individuals to adverse respiratory health. OBJECTIVE: To examine the association of early-life airway bacterial carriage with respiratory tract infections and vice versa, and of early-life airway bacterial carriage with wheezing, lung function, and asthma in later childhood. METHODS: We collected upper airway swabs for bacterial culturing for S aureus, H influenzae, M catarrhalis, and H influenzae at six timepoints between the ages of 6 weeks and 6 years among 945 children participating in a population-based prospective cohort study. Information on respiratory tract infections and wheezing until age 6 years, and asthma at age 10 years was obtained by questionnaires. Lung function at age 10 years was measured by spirometry. We tested possible bidirectional associations between airway bacterial carriage and respiratory tract infections by cross-lagged models, and associations of repeatedly measured airway bacterial carriage with wheezing, lung function, and asthma by generalized estimating equations models and regression models. RESULTS: Cross-lagged modeling showed that early-life airway bacterial carriage was not consistently associated with upper and lower respiratory tract infections or vice versa. Nasopharyngeal carriage with any bacteria in infancy was associated with an increased risk of wheezing (OR [95% CI]: 1.66 [1.31, 2.10]). Airway bacterial carriage was not consistently associated with school-age lung function or asthma. CONCLUSION: Nasopharyngeal carriage with any bacteria is associated with wheezing, but not respiratory tract infections, asthma, or lung function.

Cross talk between Hsp72, HMGB1 and RAGE/ERK1/2 signaling in the pathogenesis of bronchial asthma in obese patients.

BACKGROUND: The incidence of obesity-related asthma has shown a remarkable increase. OBJECTIVES: We aimed to explore the role of heat shock protein 72 (Hsp72) and receptor for advanced glycation end products (RAGE) axis with its downstream signaling in the pathogenesis of obesity-related asthma. METHODS: We enrolled a total of 55 subjects and divided them into three groups. Groups I and II included healthy, normal weight (n = 15) and obese (n = 15) subjects, respectively. Twenty-five obese asthmatics (group III) were subdivided into group IIIa (10 patients with mild to moderate asthma) and group IIIb (15 patients with severe asthma). High mobility group box 1 (HMGB1), interleukin 8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), extracellular signal-regulated protein kinases 1 and 2 (ERK1/2), and urinary Hsp72 were immunoassayed. Hydrogen peroxide (H2O2) and free fatty acids (FFAs) levels were photometrically measured. RAGE mRNA expression was relatively quantified by real-time PCR. RESULTS: We found significant elevations of serum HMGB1, IL-8, MCP1, ERK1/2, FFAs, and H2O2 levels as well as urinary Hsp72 levels in obese subjects compared to healthy control. These were more evident in patients with severe asthma (group IIIb). Multivariate regression analysis identified Hsp72 and ERK1/2 as independent predictors of bronchial asthma severity. Receiver operating characteristic (ROC) curve analysis revealed that areas under the curve (AUC) for Hsp72 and ERK1/2 were 0.991 and 0.981, respectively, which denotes a strong predictive value for identifying the severity of bronchial asthma in obese patients. CONCLUSION: The current study highlights the role of Hsp72 and HMGB1/RAGE/ERK1/2 signaling cascade in the pathogenesis of bronchial asthma and its link to obesity, which could be reflected on monitoring, severity grading, and management of this disease.

The relationship between systolic pulmonary arterial pressure and Tp-e interval, Tp-e/QT, and Tp-e/QTc ratios in patients with newly diagnosed chronic obstructive pulmonary disease.

INTRODUCTION: The risk of sudden cardiac death (SCD) and arrhythmias has been shown to be common in chronic obstructive pulmonary disease (COPD) subjects. We aimed to evaluate the markers of arrhythmia such as QT, QTc (corrected QT), Tp-e, and cTp-e (corrected Tp-e) intervals, Tp-e/QT ratio, and Tp-e/QTc ratio in newly diagnosed COPD subjects in both right and left precordial leads. MATERIALS AND METHODS: The study group consisted of 74 subjects with obstructive respiratory function tests (RFTs). The control group consisted of 78 subjects who had nonobstructive RFTs. RFTs, electrocardiograms (ECG), and transthoracic echocardiograms (TTE) were performed, and QTR (QT interval in right precordial leads), QTL (QT interval in left precordial leads), Tp-eR (Tp-e interval in right precordial leads), and Tp-eL (Tp-e interval in left precordial leads) intervals; systolic pulmonary arterial pressure (sPAP); forced expiratory volume in one second (FEV1 )/forced vital capacity (FVC); and peripheral oxygen saturation(POS) values were measured. RESULTS: Tp-eR interval 85.82 ± 5.34 millisecond (ms) versus 62.87 ± 3.55 ms (t = 31.29/p < .00001), cTp-eR interval 97.51 ± 7.18 ms versus 71.07 ± 4.58 ms (t = 27.20/p < .00001), Tp-eR/QTR ratio 0.234 ± 0.02 versus 0.164 ± 0.01 (t = 2.2/p = .014), and Tp-eR/QTcR ratio 0.201 ± 0.01 versus 0.141 ± 0.01 (t = 1.92/p = .028) were statistically significantly higher in COPD subjects. There was a strong negative correlation between RFT and sPAP (sPAP, 29.93 ± 5.1 mm Hg; and FEV1 /FVC, 63.78 ± 3.33%, r = -.85/p < .00001). There was a moderate positive correlation between sPAP and Tp-eR. CONCLUSION: We found Tp-e and cTp-e intervals, Tp-e/QT ratio, and Tp-e/QTc ratio were significantly higher in the COPD patients than in the control group. In addition, in the COPD group, heart rate variability (HRV) parameters were significantly lower on ECG.

Respiratory health profile of Indigenous Australian children and young adults.

AIM: National data report respiratory illness to be the most common chronic illness in Australian Indigenous people aged <35 years but multi-centre data on specific diseases is sparse. Respiratory health is now known to be an independent predictor of future all-cause mortality and cardiovascular disease. We aimed to describe the respiratory health profile (clinical and spirometry data) of randomly recruited Indigenous Australian children and young adults from several sites. METHODS: As part of the Indigenous Respiratory Reference Values study, 1278 Australian Indigenous children and young adults (aged 3-25 years) were recruited from nine communities (Queensland, n = 8; Northern Territory, n = 1). Self-reported and medical records were used to ascertain respiratory history. Participants were classified as 'healthy' if there was no current/previous respiratory disease history. Spirometry was performed on all participants and assessed according to forced expiratory volume at 1 s impairment. RESULTS: Medical history data were available for 1245 (97.4%) and spirometry for 1106 participants (86.5%). Asthma and bronchitis were the most commonly reported respiratory conditions (city/regional 19.5% and rural/remote 16.8%, respectively). Participants with a history of any respiratory disease or those living in rural/remote communities had lower lung function compared to the 'healthy' group. Almost 52.0% of the entire cohort had mild-moderate forced expiratory volume at 1 s impairment (47.7% in 'healthy' group, 58.5% in 'respiratory history' group). CONCLUSION: The high prevalence of poor respiratory health among Indigenous Australian children/young adults places them at increased risk of future all-cause mortality and cardiovascular disease. Respiratory assessments including spirometry should be part of the routine evaluation of Indigenous Australians.

Predicting the outcome of respiratory disease in wheezing infants using tidal flow-volume loop shape.

INTRODUCTION AND OBJECTIVES: Wheezing (RW) infants with a positive asthma predictive index (API+) have a lower lung function as measured by forced expiratory techniques. Tidal flow-volume loops (TFVL) are easy to perform in infants, and sedation is not necessary. MATERIALS AND METHODS: A total of 216 wheezing infants were successfully measured, and 183 of them were followed for over a year. TFVL loops were classified into one of three categories depending of their geometric shape (symmetric, convex, and concave). Respiratory rate (Rr), presence of API+, and the number of exacerbations during the following year were also recorded. RESULTS: Children with concave loops had more exacerbations in the following year (OR = 6.8 [IC95% 3.33;13.91]). Infants API + were also significantly more related to concave loops (OR = 10.02 [IC 95% 4.53; 22.15]). Rr was higher in infants with concave loops (44+/-15.5 vs. 36.6 +/-12.6; p < 0.01). CONCLUSION: Infants with a concave TFVL have a higher probability of experiencing exacerbations in the following year, and are at a higher risk of suffering asthma.

Risk factors for postoperative pneumonia according to examination findings before surgery under general anesthesia.

OBJECTIVE: This study was performed to determine the risk factors associated with postoperative complications after surgery under general anesthesia according to respiratory function test results and oral conditions. MATERIALS AND METHODS: Preoperative examination data were collected for 471 patients who underwent surgery under general anesthesia at the Medical Hospital of Kyusyu University. Respiratory function tests, oral examinations, and perioperative oral management were performed in all patients. The incidence of and risk factors for postoperative complications were investigated. Classification and regression tree analyses were performed to investigate the risk factors for postoperative complications. RESULTS: Among the 471 patients, 11 developed postoperative pneumonia, 10 developed postoperative respiratory symptoms, and 10 developed postoperative fever. The most important risk factor for pneumonia was edentulism. Age, the Brinkman index, and head and neck surgery were also revealed as important risk factors for pneumonia. The O'Leary plaque control record (initial visit) was an important risk factor for postoperative respiratory symptoms. With respect to postoperative fever, a Hugh-Jones classification of grade > 1 was the most important risk factor; edentulism and a Brinkman index of > 642.5 were also found to be risk factors. CONCLUSION: In addition to respiratory function tests, oral examinations may be important for the prediction of postoperative complications. Additionally, improved oral hygiene may be effective in preventing postoperative respiratory complications. CLINICAL RELEVANCE: Risk factors for postoperative complications should be comprehensively evaluated using both respiratory function tests and oral findings.

Quantitative assessment of airway remodelling and response to allergen in asthma.

BACKGROUND AND OBJECTIVE: In vivo evaluation of the microstructural differences between asthmatic and non-asthmatic airways and their functional consequences is relevant to understanding and, potentially, treating asthma. In this study, we use endobronchial optical coherence tomography to investigate how allergic airways with asthma differ from allergic non-asthmatic airways in baseline microstructure and in response to allergen challenge. METHODS: A total of 45 subjects completed the study, including 20 allergic, mildly asthmatic individuals, 22 non-asthmatic allergic controls and 3 healthy controls. A 3-cm airway segment in the right middle and right upper lobe were imaged in each subject immediately before and 24 h following segmental allergen challenge to the right middle lobe. Relationships between optical airway measurements (epithelial and mucosal thicknesses, mucosal buckling and mucus) and airway obstruction (FEV1 /FVC (forced expiratory volume in 1 s/forced vital capacity) and FEV1 % (FEV1 as a percentage of predictive value)) were investigated. RESULTS: Significant increases at baseline and in response to allergen were observed for all four of our imaging metrics in the asthmatic airways compared to the non-asthmatic airways. Epithelial thickness and mucosal buckling exhibited a significant relationship to FEV1 /FVC in the asthmatic group. CONCLUSION: Simultaneous assessments of airway microstructure, buckling and mucus revealed both structural and functional differences between the mildly asthmatic and control groups, with airway buckling seeming to be the most relevant factor. The results of this study demonstrate that a comprehensive, microstructural approach to assessing the airways may be important in future asthma studies as well as in the monitoring and treatment of asthma.

Efficacy and Safety of Pirfenidone in Advanced Idiopathic Pulmonary Fibrosis.

BACKGROUND: Although phase 3 trials showed significant efficacy and acceptable safety profiles for pirfenidone in mild-to-moderate idiopathic pulmonary fibrosis (IPF), data on advanced IPF are limited. OBJECTIVES: The study aimed to evaluate the efficacy and safety of pirfenidone in advanced IPF patients. METHODS: The clinical data of 138 IPF patients (advanced group: 27%) treated with pirfenidone were retrospectively reviewed and compared between advanced and non-advanced groups. Advanced IPF was defined as (1) forced vital capacity (FVC) < 50% predicted or (2) diffusing capacity for carbon monoxide < 30% predicted. RESULTS: The mean treatment duration was 51.3 weeks, and lung function analysis was performed in 81 patients (17 in the advanced group). Changes in FVC and total lung capacity (TLC) were significantly reduced at 6 months after treatment in both the advanced (ΔFVC [6 months]: -6.3 [before] vs. 0.7% predicted [after]; ΔTLC: -5.3 vs. 0.8) and non-advanced (ΔFVC: -3.4 vs. 0.5; ΔTLC: -3.1 vs. -0.9) groups. The rate of decline in FVC and TLC was significant before treatment, but not after treatment in the advanced (FVC: -1.27 [before] vs. 0.21% predicted/month [after]; TLC: -0.89 vs. -0.15) and non-advanced (FVC: -0.60 vs. -0.20; TLC: -0.54 vs. -0.17) groups. The advanced group showed a similar rate of adverse events (AEs) (78.4 vs. 88.1%, p = 0.270), but more serious AEs (40.5 vs. 10.9%, p < 0.001) including death (24.3 vs. 5.0%, p = 0.002). CONCLUSIONS: In advanced IPF, pirfenidone showed similar efficacy and safety to non-advanced IPF except for serious AEs, which may be due to the advanced status itself.

Zero-Balance Ultrafiltration of Priming Blood Attenuates Procalcitonin and Improves the Respiratory Function in Infants After Cardiopulmonary Bypass: A Randomized Controlled Trial.

Blood priming is needed for cardiopulmonary bypass (CPB) in neonates and infants to avoid exceeding hemodilution; however, transfusion-related inflammation affects post-CPB outcomes in infant open-heart surgery. Procalcitonin, a newly detected inflammatory moderator and a sensitive parameter for predicting pulmonary dysfunction secondary to CPB, rises after CPB. We hypothesized that the hemofiltration of priming blood before CPB might decrease inflammatory mediators in the blood and post-CPB inflammatory replications, thereby improving the respiratory function after CPB in infants. Sixty infants with a weight below 10 kg were divided randomly into two equal groups of CPB with the zero-balance ultrafiltration (Z-BUF) of priming blood and CPB without it. The procalcitonin level was measured before anesthesia, after admission to the intensive care unit (ICU), and 24 h afterward. The respiratory index and pulmonary compliance were measured after anesthesia, at the end of CPB, and 2 h after admission to the ICU. Additionally, time to extubation was recorded. The Z-BUF of priming blood maintained electrolytes within a physiologic level, and procalcitonin had a slighter rise in the Z-BUF Group at 24 h after admission to the ICU (P = 0.05). The respiratory index was decreased in the Z-BUF Group, but the difference with the control group did not reach statistical significance (P > 0.05). The change in pulmonary compliance was significantly increased in the cyanotic patients in the intervention group, but there was no significant difference between the two groups. The time to extubation and the ICU stay were shorter in the Z-BUF Group (P < 0.05). A positive correlation was found between the peak procalcitonin concentration and the time to extubation directly and pulmonary compliance reversely. These results suggest that the Z-BUF of priming blood may have some beneficial clinical effects such as improved respiratory function and attenuated procalcitonin.

Substantial variation exists in spirometry interpretation practices for airflow obstruction in accredited lung function laboratories across Australia and New Zealand.

BACKGROUND: Spirometry forms the foundation investigation for the diagnosis and monitoring of common pulmonary conditions. However, potential variation in spirometry interpretation for airflow obstruction may impact subsequent clinical management. AIM: To audit spirometry interpretation practices for airflow obstruction in Thoracic Society of Australia and New Zealand accredited laboratories. METHODS: Thirty-nine accredited complex lung function laboratories were invited to participate in an online survey. The survey enquired about demographics, definition of lower limit of normal range for spirometry parameters, spirometric parameters used for identifying airflow obstruction, spirometric definition of airflow obstruction, definition of significant bronchodilator response and chosen spirometry reference equations. RESULTS: Thirty-six laboratories provided complete responses (response rate, 92%). To define the lower limit of normal, 26 of 36 used the 5th percentile, 7 of 36 used a fixed cut-off and 3 used other. Twenty-nine laboratories utilised forced expiratory volume in 1 s/forced vital capacity (FEV1 /FVC) as the sole parameter to identify airflow obstruction, 3 of 36 used FEV1 /FVC and FEF25-75% , and 4 used other. To define airflow obstruction, 25 of 36 laboratories used FEV1 /FVC < 5th percentile, 9 of 36 used a fixed cut-off (FEV1 /FVC < 0.7, 6/36; FEV1 /FVC < 0.8, 2/36; FEV1 /FVC < 0.75, 1/36) and 2 of 36 used other. Twenty-six laboratories defined a significant bronchodilator response as an increase of at least 200 mL and 12% in FEV1 and/or FVC, 9 of 36 used ≥200 mL and ≥ 12% increase in FEV1 only, and 1 used other criteria. Reference equations utilised for interpretation of spirometry data included: Quanjer 2012 Global Lung Initiative (16/36), the third National Health and Nutritional Examination Survey (8/36), European Community of Coal and Steel (8/36) and other (4/36). CONCLUSIONS: Significant heterogeneity in spirometry interpretation for airflow obstruction exists across Australian and New Zealand accredited lung function laboratories. Lack of standardisation may translate into clinically appreciable differences for the diagnosis and management of common respiratory conditions. Ongoing discussion regarding formal standardisation is required.