Total Airway Resistance Research Articles

2592. Lung Function as an Indicator of Vaccine Enhanced RSV Disease in Cotton Rats

BackgroundRespiratory syncytial virus (RSV) infection is the leading cause of lower respiratory tract infections in infants and young children. Seronegative children previously vaccinated with formalin-inactivated live RSV formulated with aluminum (FIRSV) developed vaccine enhanced RSV disease (VERD), which is characterized by fever, wheezing, bronchopneumonia, and airway hyperresponsiveness (AHR). We investigated whether impaired lung function can serve as a marker for VERD in an animal model of RSV infection.MethodsUninfected and RSV-infected cotton rats intranasally challenged with 106 pfu of RSV A2 were anesthetized with pentobarbital and tracheostomized. A cannula was placed in the trachea and animals were connected to flexiVent™ (Scireq), which is a computer-controlled piston ventilator that analyzes pressure and volume signals in response to an oscillatory waveform applied at the animal’s airways. Vecuronium bromide was administered to ventilated animals to prevent independent breathing. To measure AHR, animals were exposed to increasing doses of inhaled methacholine, and methacholine-induced bronchoconstriction was measured.ResultsTwo independent studies showed that RSV-infected cotton rats (n = 4) exhibited increased total respiratory system resistance (Rrs) and airway resistance (Rn) following methacholine challenge on days 4 and 6 post-infection compared with uninfected cotton rats (n = 4).ConclusionRSV-induced impairment in lung function can be exploited for the development of a more robust and objective method for assessing vaccine safety in a cotton rat model of respiratory disease compared with traditional histopathological analysis.Disclosures All authors: No reported disclosures.

Impulse Oscillometry

Pulmonary function testing involves a battery of tests from the simple pulse oximetry to the cardiopulmonary exercise testing. Impulse oscillometry (IOS) is one of the newly described pulmonary function tests. It is based on the old principle of forced oscillatory technique modified and refined as per research and advances. It involves the use of sound waves during normal tidal breathing, which gives information on oscillatory pressure-flow relationships and eventually resistance and reactance. The resistance at 20 Hz (R20) represents the resistance of the large airways. The resistance at 5 Hz (R5) means the total airway resistance. (R5-R20) reflects resistance in the small airways. The reactance at 5 Hz (X5) indicates the elastic recoil of the peripheral airways. Resonant frequency and area of reactance are also measured. IOS has major uses in diagnosis and control of asthma in children and the elderly, where spirometry is otherwise normal. IOS has been studied in other respiratory diseases like COPD, ILD and supraglottic stenosis.

Acute Effects of Oscillatory PEP and Thoracic Compression on Secretion Removal and Impedance of the Respiratory System in Non-Cystic Fibrosis Bronchiectasis.

Bronchiectasis is characterized by abnormal and permanent dilatation of the bronchi, caused mainly by the progression of inflammatory processes and loss of the ability to remove mucus. Techniques to clear the airways are essential for the treatment of these patients. In this study, we aimed to evaluate the acute effects of oscillatory PEP and thoracic compression on both the clearance of secretions and impedance of airways in subjects with bronchiectasis. This was a randomized crossover single-blinded study that involved both subjects with bronchiectasis and healthy subjects evaluated by using an impulse oscillometry system, which assessed resistance at 5 Hz and resistance 20 Hz, reactance at 5 Hz, reactance area, and resonant frequency, before, after, and 30 min after oscillatory PEP, chest compression, or control sessions. Dry and total weights, adhesiveness, purulence of the expectorated secretions, the dyspnea scale score, the acceptability and tolerance scale score, pulse oximetry, and difficulty in expectoration were also assessed. The dry and total weights of secretions were higher after the use of the oscillatory PEP technique than those in a control session (P = .005 and P = .039, respectively). In the bronchiectasis group, there was a decrease after oscillatory PEP in total airway resistance (P = .04), peripheral resistance (P = .005), and reactance area (P = .001). After compression, there was a decrease in peripheral resistance Hz (P = .001) and reactance area (P = .001). In the healthy group, there was an increase in resistance at 5 Hz (P = .02) after oscillatory PEP. There were no differences in acceptability and tolerance, dyspnea, and oxygen saturation. The oscillatory PEP technique was effective for the removal of secretions and in decreasing total and peripheral respiratory system resistance; thoracic compression had comparable positive effects on the peripheral resistance. Both techniques were safe and well tolerated by the subjects with bronchiectasis. ClinicalTrials.gov registration NCT02509637.).

Small and large airways’ reactions to inhaled capsaicin in patients with chronic idiopathic cough, or asthma and in healthy control subjects

Aims: Cough is a common medical problem, and when it persists for more than 8 weeks it is arbitrarily defined as chronic. While spirometry assesses the large airways, impulse oscillometry system (IOS) measures peripheral airway function. The present study investigated whether provocation with inhaled capsaicin affects the large and small airways in patients with chronic idiopathic cough (CIC) or asthma and in healthy controls. Materials and methods: Twenty-one patients with CIC, 18 patients with asthma, and 22 healthy controls were subjected to a provocation with capsaicin, and lung function was assessed by IOS and spirometry. Results: At baseline, before the capsaicin provocation, the CIC group had significantly increased airway resistance compared to the controls. After capsaicin provocation, the CIC group exhibited a significant increase in total airway resistance. The asthma group showed a small but significant reduction in spirometry, increased airway resistance, and reactance after capsaicin provocation. Capsaicin inhalation affected neither the spirometry nor the IOS of the healthy controls. Conclusions: The present study demonstrates that inhaled capsaicin induces changes in lung function, both in patients with CIC and in patients with asthma, when IOS, which measures changes also in the peripheral airways, is used. IOS appears to be a more sensitive tool than spirometry for the detection of airway impairment in airway provocation studies. In patients with CIC, higher peripheral resistance at baseline may have clinical significance.

Impulse Oscillometry Discerns the Peripheral Airway Response to an Inhaled Bronchodilator between Obese and Nonobese Children

IntroductionImpulse oscillometry (iOS) is a useful tool to distinguish between central and peripheral airway resistance. For example, iOS has shown that peripheral airway resistance is greater in children with versus those without obesity, despite no difference in FEV1. Considering the added peripheral airway resistance in children with obesity, we sought to determine if iOS can detect potential differences in the peripheral airway response to an inhaled bronchodilator (BD) between children with and those without obesity.MethodsTwenty‐four children with and eleven without obesity, ages 8–12yrs, completed iOS and spirometry testing before and 15mins after the administration of four puffs of an inhaled BD (Ventolin®, 90μg). A mixed models ANOVA (group by pre‐to‐post‐BD) was used to determine differences in FEV1, plethysmographic airway resistance (Raw) and specific Raw (sRaw), and iOS parameters associated with airway resistance. These parameters include resistance at 5 Hz, 10 Hz (R5 and R10: total airway resistance), 20 Hz (R20: large airway resistance), and the difference between R5 and R20 (R5–20: peripheral airway resistance). Reactance at 5 Hz (X5: total airway elastic recoil) and the area under the reactance‐frequency curve (AX: index of small airway patency) were also measured using iOS.ResultsThere was no difference in FEV1 (% pred) or FEV1/FVC between groups and none of our participants showed a positive BD response based on the conventional method of a ≥12% increase in FEV1. Compared with children without obesity, children with obesity presented a greater baseline R5 (7.28 ± 1.20 vs. 5.42 ± 1.44 cmH2O·L−1·s−1; p=0.001), R10 (6.04 ± 1.12 vs. 4.58 ± 1.07 cmH2O·L−1·s−1; p=0.002), R20 (4.76 ± 0.95 vs. 3.94 ± 0.79 cmH2O·L−1·s−1; p=0.025), R5–20 (2.52 ± 0.64 vs. 1.49 ± 0.75 cmH2O·L−1·s−1; p<0.001), and AX (7.65 ± 5.59 vs. 3.75 ± 1.97 cmH2O·L−1; p=0.008), with no difference in X5 (−1.19 ± 0.77 vs. −1.19 ± 0.33 cmH2O·L−1; p=0.667). A group by pre‐to‐post‐BD interaction was found for R5 (p=0.033) and R10 (p=0.024). Both R5 and R10 decreased to a greater extent with BD in children with obesity versus children without obesity (R5: −20.8 ± 9.5% vs. −12.8 ± 15.2%; R10: −21.6 ± 8.6% vs. −14.5 ± 13.1%). In all children (n=35), Raw, sRaw, and all iOS parameters, except for X5, decreased with the BD (p<0.05).ConclusionIn addition to greater central and peripheral airway resistance in children with obesity, iOS also detected a greater peripheral airway response to a BD in children with obesity. Although no established criteria exist for children ages 8–12yrs, the American Thoracic Society defines an airway response in preschool children as a 20–40% decrease in R5 and a 15–30% decrease in R10. Based on these criteria, our finding that R5 and R10 dropped by 20.8% and 21.6% in children with obesity indicates potential peripheral airway hyperresponsiveness in children with obesity. However, further research is warranted to establish the meaning of, or normal criteria for, peripheral airway responsiveness in prepubescent children.Support or Funding InformationNIH R01 HL136643, Texas Health Presbyterian Hospital Dallas, King Charitable Foundation Trust, and Dr. Pepper Snapple.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Эффекты добавочного дыхательного сопротивления у подростков с повышенным тонусом симпатической нервной системы

Изучены закономерности изменения вегетативного компонента регуляции деятельности сердца при включении дозированного дыхания с добавочным сопротивлением (ДДС) у подростков с исходным преобладанием тонуса симпатической нервной системы (ПТСНС). Методы. В исследовании приняли участие 17 человек, из них 8 юношей и 9 девушек, в возрасте от 14 до 17 лет. Всем добровольцам проводили регистрацию кардиоинтервалограммы с анализом вариабельности сердечного ритма (ВСР) до и во время дыхания c ДДС. Проводили анализ ВСР с выявлением вегетативного тонуса у детей с исходно ПТСНС. Результаты. Выявлено значимое снижение тонуса симпатической и возрастание тонуса парасимпатической нервной системы у детей с ПТСНС. Результаты работы позволяют прогнозировать изменения вегетативной регуляции деятельности сердца у детей в условиях закрытого помещения с длительно находящимися там людьми. Changes in neurogenic regulation of the heart function were studied after the onset of dosed lung ventilation with artificially increased total airway resistance in 8 male and 9 female adolescents aged 14-17 with originally high tone of the sympathetic system. Analysis of cardiointervalography and heart rate variability showed a significant decrease in sympathetic tone and an increase in parasympathetic tone due to the respiration with additional resistance, which can be regarded as a model for prediction of changes in neurogenic regulation of the heart function in children after a lengthy stay in a stuffy, enclosed area.

Impulse oscillometry to differentiate between chronic obstructive pulmonary disease and bronchial asthma

BackgroundThe impulse oscillation system (IOS) yields useful clinical data that predominantly include functional assessment of peripheral airways more than that available from commonly used spirometry. The aim of this study was to differentiate between chronic obstructive pulmonary disease (COPD) and bronchial asthma using IOS.Patients and methodsThis study was carried out on 40 patients; 20 patients were diagnosed with bronchial asthma and the remaining 20 patients had a clinical diagnosis of COPD. All patients underwent baseline IOS and spirometry, and then after 15 min of inhalation of 400 μg salbutamol, spirometry was repeated in all patients.ResultsA highly statistically significant difference was found between asthma patients and COPD patients in R20, whereas no statistically significant difference was found between the two studied groups in R5, X5. There was a statistically significant difference between asthma patients and COPD patients in resistance; 75% of asthmatic patients had increased total airway resistance, mainly proximal, 20% had increased total airway resistance, mainly peripheral, and 5% had normal airway resistance, whereas all COPD patients had increased total airway resistance, mainly peripheral. No significant correlation was found between IOS parameters and spirometric parameters in COPD or asthmatic patients, but in both groups, there was a significant correlation between forced expiratory volume 1 (FEV1) and R5, X5.ConclusionIOS provides useful clinical information that prominently includes functional assessment of small, peripheral airway behavior beyond that available from commonly used pulmonary function tests. IOS also aids differentiation between COPD and bronchial asthma. COPD patients had increased airway resistance, mainly in the peripheral airways, whereas asthmatic patients had increased airway resistance, mainly in the proximal airways. R20 is the best IOS parameter to differentiate between these two diseases.

Machine Learning Algorithms Utilizing Functional Respiratory Imaging May Predict COPD Exacerbations

Acute chronic obstructive pulmonary disease exacerbations (AECOPD) have a significant negative impact on the quality of life and accelerate progression of the disease. Functional respiratory imaging (FRI) has the potential to better characterize this disease. The purpose of this study was to identify FRI parameters specific to AECOPD and assess their ability to predict future AECOPD, by use of machine learning algorithms, enabling a better understanding and quantification of disease manifestation and progression. A multicenter cohort of 62 patients with COPD was analyzed. FRI obtained from baseline high resolution CT data (unenhanced and volume gated), clinical, and pulmonary function test were analyzed and incorporated into machine learning algorithms. A total of 11 baseline FRI parameters could significantly distinguish ( p < 0.05) the development of AECOPD from a stable period. In contrast, no baseline clinical or pulmonary function test parameters allowed significant classification. Furthermore, using Support Vector Machines, an accuracy of 80.65% and positive predictive value of 82.35% could be obtained by combining baseline FRI features such as total specific image-based airway volume and total specific image-based airway resistance, measured at functional residual capacity. Patients who developed an AECOPD, showed significantly smaller airway volumes and (hence) significantly higher airway resistances at baseline. This study indicates that FRI is a sensitive tool (PPV 82.35%) for predicting future AECOPD on a patient specific level in contrast to classical clinical parameters.

Effect of electroacupuncture on expressions of acetylcholine and mucin 5AC in the lungs of rats with chronic obstructive pulmonary disease

To observe the effect of electroacupuncture (EA) on the expressions of acetylcholine (ACh) and mucin 5AC (MUC5AC) in the lungs of rats with chronic obstructive pulmonary disease (COPD), and explore the mechanism of EA in treating COPD. Thirty Sprague-Dawley (SD) rats were randomly divided into a control group, a COPD group, and an EA group, with 10 rats in each group. The control group was a group of normal rats. The COPD rat model was induced by cigarette smoke combined with lipopolysaccharide (LPS). The COPD rats were treated with EA at bilateral Feishu (BL 13) and Zusanli (ST 36) in the EA group, 30 min each time, once a day, successively for 14 d. The lung function was tested. The contents of ACh and MUC5AC in lungs and bronchoalveolar lavage fluid (BALF) were detected by enzyme-linked immunosorbent assay (ELISA). Pearson method was used to analyze the correlation between pulmonary function and the content of MUC5AC in lungs. The mRNA and protein expressions of MUC5AC in lung tissues were detected by real-time polymerase chain reaction (RT-PCR) and Western blot (WB), respectively. The immune response of MUC5AC was observed by immunohistochemistry. Eight rats were left in each group, and the other two died. Compared with the control group, the total airway resistance (Raw) increased significantly and dynamic compliance (Cdyn) decreased significantly in the COPD group (P<0.01); compared with the COPD group, the Raw level declined significantly and Cdyn increased significantly in the EA group (P<0.01). The contents of ACh and MUC5AC in the lungs and BALF were remarkably higher in the COPD group compared with those in the control group (P<0.01, P<0.001); compared with the COPD group, the contents of ACh and MUC5AC were significantly lower in the EA group (P<0.05, P<0.001). There was a negative correlation between MUC5AC content and lung function (P<0.001). The mRNA and protein expressions of MUC5AC in the lungs were significantly higher in the COPD group than in the control group (P<0.001); compared with the COPD group, the expressions were significantly lower in the EA group (P<0.01). Compared with the control group, the immune response of MUC5AC in the airway epithelium significantly increased in the COPD group (P<0.001); the immune response of MUC5AC was significantly lower in the EA group compared with that in the COPD group (P<0.001). EA treatment can improve the lung function of COPD rats, which may be related to its effect in the down-regulation of ACh and MUC5AC contents in the lungs as well as the inhibition of mucus hypersecretion.

Longitudinal Evaluation of Lung Function in Patients With Advanced Non-Small Cell Lung Cancer Treated With Concurrent Chemoradiation Therapy

In lung cancer patients, radiation therapy modifies lung architecture, resulting in functional deterioration, which worsens symptoms and reduces quality of life. A multicenter, prospective, longitudinal study was conducted in a cohort of patients with locally advanced and oligometastatic non-small cell lung cancer treated with concurrent chemoradiation therapy (CCRT). A wide array of pulmonary function tests (forced spirometry, body plethysmography, impulse oscillometry, carbon monoxide diffusing capacity, fraction of exhaled nitric oxide, arterial blood gases, and 6-minute walk test) were used to evaluate lung function at baseline; after radiation therapy; and at 6, 12, 24, and 48weeks after CCRT. Relative changes in test results (percentages) were estimated at the aforementioned intervals and compared with baseline results. Thirty-seven patients completed the follow-up and were included in the analysis. After CCRT, patients showed a maximum decline in lung volumes as follows: (1) 31% in forced expiratory volume in the first second after 24weeks (P=.008), (2) 9.6% in forced vital capacity after 48weeks (P=.04), and (3) 15.1% in total lung capacity after 48weeks (P=.0015).Similarly, at 12weeks after CCRT, patients showed a 21.8% decrease in carbon monoxide diffusing capacity (P=.002). Increases were found in total airway resistance (respiratory system resistance at 5Hz), frequency dependence of resistance (change in respiratory system resistance at 5 Hz-respiratory system resistance at 20Hz, P=.012), and reactance (P=.0003 for respiratory system reactance at 5Hz and P=.001 for reactance area), which together indicate small-airway dysfunction. The longitudinal evaluation of lung function through pulmonary function tests detects CCRT-induced damage before the appearance of clinical symptoms associated with CCRT lung toxicity.

Gender differences in morphological and functional outcomes after mandibular setback surgery

PurposeThe aim of this study was to examine and compare morphological and functional outcomes after either isolated mandibular setback or bimaxillary surgery in males and females. Materials and methodsA retrospective study was done on 52 patients, in whom surgical correction for mandibular prognathism was performed either by isolated mandibular setback (30 cases) or by bimaxillary surgery (22 cases). Morphological changes were studied using cephalograms and functional changes studied using impulse oscillometry (IOS) taken before surgery (T0), 3 months (T1) and 1 year after surgery (T2). Also 3% oxygen desaturation index (ODI) was measured at T0 and T2. ResultPosterior airway space decreased significantly in both groups and both sexes but more so in males after mandibular setback surgery and in females after bimaxillary surgery. Changes in supine R20 (central airway resistance at 20 Hz) and supine R5 (total airway resistance at 5 Hz) in IOS statistically significantly increased in the period T0–T1 in males compared with females after mandibular setback surgery (p < 0.05). ConclusionGender dimorphism is present according to morphological and functional outcomes, with males at a higher risk for obstructive sleep apnea (OSA) after mandibular setback surgery and females after bimaxillary surgery; however, compensatory changes act as a barrier against this.

IMPULSE OSCILLOMETRY AND SPIROMETRY IN SCHOOLERS SUBMITTED TO THE SIX-MINUTE WALK TEST.

ABSTRACTObjective: To verify repercussions of submaximal exercise testing on respiratory mechanics and pulmonary function in schoolchildren.Methods: Cross-sectional study, with children aged 7 to 14 years, who had their respiratory mechanics assessed by impulse oscillometry (IOS), and pulmonary function by spirometry. They performed the six-minute walk test (6MWT), as per the standards by the American Thoracic Society. The 6MWT was performed twice with a 30-minute interval. IOS and spirometry were performed before the first 6MWT (Pre-6MWT) and immediately after the first (Post-6MWT1) and second walking tests (Post-6MWT2). The results in these three phases were compared by analysis of variance for repeated measures (post-hoc Bonferroni test) or by the Friedman’s test, with p≤0.05 considered significant.Results: Twenty-one subjects participated in the study: 53% were males and mean age was 10.9±2.3 years. There were differences between total resistance (R5) and central airway resistance (R20) at the three phases of assessment (p=0.025 and p=0.041, respectively). Post-hoc analysis indicated increase in R5 when Pre-6MWT and Post-6MWT1 were compared (R5=0.540±0.100 versus 0.590±0.150 kPa/L/s, p=0.013; and R20=0.440±0.800 versus 0.470±0.100 kPa/L/s, p=0.038). Forced expiratory flow 25-75% (FEF25-75%) changed over time (p=0.003).Conclusions: Repercussions were: increase in central and total airway resistance and reduction of FEF25-75% after 6MWT in schoolchildren, suggesting that greater attention should be given to submaximal tests in children with predisposition to airways alterations.

The airway hyperresponsiveness to methacholine may be predicted by impulse oscillometry and plethysmography in children with well-controlled asthma

ABSTRACTObjective: Airway hyperresponsiveness (AHR) is a hallmark of asthma. Methacholine challenge test which is mostly used to confirm AHR is not routinely available. The aim of this study was to investigate the predictive values of fractional exhaled nitric oxide (FeNO), impulse oscillometry (IOS), and plethysmography for the assessment of AHR in children with well-controlled asthma. Methods: 60 children with controlled allergic asthma aged 6–18 years participated in the study. FeNO measurement, spirometry, IOS, and plethysmography were performed. Methacholine challenge test was done to assess AHR. PC20 and dose response slope (DRS) of methacholine was calculated. Results: Mild to severe AHR with PC20 < 4 mg/ml was confirmed in 31 (51.7%) patients. Baseline FeNO and total specific airway resistance (SRtot)%pred and residual volume (RV)%pred levels in plethysmography were significantly higher and FEV1%pred, FEV1/FVC%pred, MMEF%pred values were lower in the group with PC20 < 4 mg/ml. FeNO, SRtot%pred, and RV%pred levels were found to be positively correlated with DRS methacholine. The higher baseline FeNO, frequency dependence of resistance (R5–R20) in IOS and SRtot%pred in plethysmography were found to be significantly related to DRS methacholine in linear regression analysis (β: 1.35, p = 0.046, β: 4.58, p = 0.002, and β: 0.78, p = 0.035, respectively). The cut-off points for FeNO and SRtot% for differentiating asthmatic children with PC20 < 4 mg/ml from those with PC20 ≥ 4 mg/ml were 28 ppb (sensitivity: 67.7%, specificity: 72.4%, p < 0.001) and 294.9% (sensitivity: 35.5%, specificity: 96.6%, p = 0.013), respectively. Conclusion: IOS and plethysmography may serve as reliable and practical tools for prediction of mild to severe methacholine induced AHR in otherwise “seemingly well-controlled’’ asthma.

Contributions of Kinetic Energy and Viscous Dissipation to Airway Resistance in Pulmonary Inspiratory and Expiratory Airflows in Successive Symmetric Airway Models With Various Bifurcation Angles.

The aim of this study was to investigate and quantify contributions of kinetic energy and viscous dissipation to airway resistance during inspiration and expiration at various flow rates in airway models of different bifurcation angles. We employed symmetric airway models up to the 20th generation with the following five different bifurcation angles at a tracheal flow rate of 20 L/min: 15 deg, 25 deg, 35 deg, 45 deg, and 55 deg. Thus, a total of ten computational fluid dynamics (CFD) simulations for both inspiration and expiration were conducted. Furthermore, we performed additional four simulations with tracheal flow rate values of 10 and 40 L/min for a bifurcation angle of 35 deg to study the effect of flow rate on inspiration and expiration. Using an energy balance equation, we quantified contributions of the pressure drop associated with kinetic energy and viscous dissipation. Kinetic energy was found to be a key variable that explained the differences in airway resistance on inspiration and expiration. The total pressure drop and airway resistance were larger during expiration than inspiration, whereas wall shear stress and viscous dissipation were larger during inspiration than expiration. The dimensional analysis demonstrated that the coefficients of kinetic energy and viscous dissipation were strongly correlated with generation number. In addition, the viscous dissipation coefficient was significantly correlated with bifurcation angle and tracheal flow rate. We performed multiple linear regressions to determine the coefficients of kinetic energy and viscous dissipation, which could be utilized to better estimate the pressure drop in broader ranges of successive bifurcation structures.

Evaluation of nasal obstruction in lowlander males in high altitude

BackgroundNasal symptoms are a major problem affecting the quality of life of lowlanders deployed at high altitude. Study was carried out in fresh male inductees inducted in high altitude of 11,500ft (3500m) above sea level to evaluate the nasal obstruction using the subjective Nasal obstruction and symptom evaluation (NOSE) score and rhinomanometry during the stay in high altitude. MethodsA prospective study was carried out in 100 males inducted into high altitude. The subjects were evaluated using the subjective assessment tool, NOSE scale and rhinomanometry on induction and after 2 months. The data were analysed for NOSE scale in the 1st and 2nd visit by test for equality of proportions and the total nasal airway resistance (Pa) has been expressed as mean±standard deviation and compared across severity of NOSE score using one way ANOVA and between 1st and 2nd visit using paired t test. Results and conclusionsOut of the 100 subjects, 77 came for the 2nd review after 2 months. There was statistically significant worsening in the subjective feeling of nasal obstruction during the stay in high altitude without any significant change in the nasal airway resistance.

Impact of sports activities on respiratory function and mechanics in children

Abstract Introduction: Being physically active in childhood may improve the quality of life in adulthood. So, it is extremely important to evaluate the respiratory function and mechanics of children who participate in sports activities, in order to determine the impact of physical activity on airway resistance. Objective: To analyze measures of respiratory function and mechanics in children who participate (PG) and who do not participate (CG) in sports activities regularly, as well as to compare and correlate the results. Methods: This is a cross-sectional analytical study of healthy school-aged children aged 6 to 12 years, assessed by impulse oscillometry tests (IOS) and spirometry. The sample was divided into PG and CG. The Student’s t-Test or Mann-Whitney test was used to compare the groups according to normality of data tested by the Shapiro-Wilk test. The correlation between the tests and age, sex, weight, height and body mass index (BMI) was performed using Pearson’s and Spearman correlation coefficient. Statistical data were processed by the SPSS® software, considering significance level at p &lt; 0.05. Results: Forty children participated in the study, 20 in each group, with no differences regarding age, sex, weight, height and BMI. There were significant differences in FEF25-75% (CG: 94.19% ± 13.08 x PG: 101.75% ± 17.44, p = 0.049), and oscillometry data did not differ between both groups. Sex correlated with total airway resistance (R5 - p = 0.049, r = 0.314). Conclusion: In the group with children who participated in sports activities, FEF25-75% was higher, compared to the control group.

COMPARISON OF SUB MUCOSAL DIATHERMY AND PARTIAL RESECTION OF INFERIOR TURBINATE IN THE TREATMENT OF SYMPTOMATIC SANAL VALVE BLOCKAGE

OBJECTIVEES: To evaluate the efficacy of sub mucosal diathermy (SMD) and partial resection of inferior turbinate (PRIT) in the treatment of symptomatic enlarged inferior turbinate. STUDY DESIGN: Prospective, METHODS: Sixty patents at age group 18 -56 yrs. with symptomatic enlarged inferior turbinate had given choices for SMD and PRIT. All the patients had history of failed medical treatment. RESULTS: Each thirty patients underwent SMD (group I), PRIT (group II), eight patients of group l, have anterior nasal packing after surgery for bleeding. Four patients complained of excessive rhinorrhea for first 2 weeks while 4 patients of Group 1 complained of nasal blockage for 1 week even after intervention. In group 2, 8 patients have re-anterior nasal packing after pack removal. Both groups followed up for 6 months. 13 patients were lost in follow up, so excluded from the study. Following 6 months of follow up, 8 patient of group I had recurrence with nasal blockage and in gr. II none had recurrence. CONCLUSION: PRIT is better than SMD in long course; nevertheless it should be reserved for failed SMD, not as a primary option. Ink described the nasal valve in 1903. The nasal valve is formed medially by the septum and laterally by the caudal edge of the upper lateral cartilage and it accounts for approximately 50% of total upper airway resistance. The anterior tip of the inferior turbinate is found in the nasal valve region, and hypertrophy of this structure can cause exponential increase in airway resistance.

The Contribution of Small Airway Obstruction to the Pathogenesis of Chronic Obstructive Pulmonary Disease.

The hypothesis that the small conducting airways were the major site of obstruction to airflow in normal lungs was introduced by Rohrer in 1915 and prevailed until Weibel introduced a quantitative method of studying lung anatomy in 1963. Green repeated Rohrer's calculations using Weibels new data in 1965 and found that the smaller conducting airways offered very little resistance to airflow. This conflict was resolved by seminal experiments conducted by Macklem and Mead in 1967, which confirmed that a small proportion of the total lower airways resistance is attributable to small airways <2 mm in diameter. Shortly thereafter, Hogg, Macklem, and Thurlbeck used this technique to show that small airways become the major site of obstruction in lungs affected by emphysema. These and other observations led Mead to write a seminal editorial in 1970 that postulated the small airways are a silent zone within normal lungs where disease can accumulate over many years without being noticed. This review provides a progress report since the 1970s on methods for detecting chronic obstructive pulmonary disease, the structural nature of small airways' disease, and the cellular and molecular mechanisms that are thought to underlie its pathogenesis.

A new infant hybrid respiratory simulator: preliminary evaluation based on clinical data.

A new hybrid (numerical-physical) simulator of the respiratory system, designed to simulate spontaneous and artificial/assisted ventilation of preterm and full-term infants underwent preliminary evaluation. A numerical, seven-compartmental model of the respiratory system mechanics allows the operator to simulate global and peripheral obstruction and restriction of the lungs. The physical part of the simulator is a piston-based construction of impedance transformer. LabVIEW real-time software coordinates the work of both parts of the simulator and its interaction with a ventilator. Using clinical data, five groups of "artificial infants" were examined: healthy full-term infants, very low-birth-weight preterm infants successfully (VLBW) and unsuccessfully extubated (VLBWun) and extremely low-birth-weight preterm infants without (ELBW) and with bronchopulmonary dysplasia (ELBW_BPD). Pressure-controlled ventilation was simulated to measure peak inspiratory pressure, mean airway pressure, total (patient+endotracheal tube) airway resistance (R), total dynamic compliance of the respiratory system (C), and total work of breathing by the ventilator (WOB). The differences between simulation and clinical parameters were not significant. High correlation coefficients between both types of data were obtained for R, C, and WOB (γ R =0.99, P<0.0005; γ C =0.85, P<0.005; γWOB=0.96, P<0.05, respectively). Thus, the simulator accurately reproduces infant respiratory system mechanics.

Impact of Hatha Yoga on the Airway Resistances in Healthy Individuals and Allergic Rhinitis Patients.

There have been limited studies on Hatha yoga training as a complementary therapy to manage the symptoms of Allergic Rhinitis. The main Aim of the study was to check the impact of Hatha yogasanas on the Airway resistances in Healthy volunteers, a baseline data can be established and also to study the impact of Hatha yogasanas on the Airway resistances in Allergic Rhinitis patients in Bangalore, India. This is a prospective case series of 51 healthy volunteers (18 Males and 33 Females) Group 1 and 51 Allergic Rhinitis patients (18 Males and 33 Females) Group 2. The Objective analysis of the upper airway resistance was measured using a rhinomanometer and the lower airway resistance was measured using a spirometer. Then the subjects practiced specific Hatha yogasanas for three months. Then the airway resistance tests were again done at 3months interval. The subjective analysis was done pre yoga and post yoga using the Short form-12 (SF-12) and Sino Nasal Outcome Test (SNOT) Questionnaires to assess the quality of life. The data was analyzed by doing a Paired (2-tailed) T Test, using SPSS (Software Package for Social Sciences) version 16. Total Nasal Airway Resistance pre yoga and post yoga in 51 healthy volunteers had significantly reduced at 150Pa and the Forced Vital Capacity(FVC) pre yoga and post yoga had significantly increased,Forced Expiratory volume (FEV1) & % Residual standard deviation (%RSD) had increased but not significant. The Physical component score (PCS) and Mental component score (MCS) of the SF-12 health survey questionnaire had significantly improved with and the SNOT questionnaire score had significantly reduced. The Total Nasal Airway Resistance in 51 Allergic Rhinitis had significantly reduced at 150Pa and the FVC pre yoga and post yoga showed increase but change was not significant, FEV1 pre yoga and post yoga had significantly increased, %RSD pre yoga and post yoga had significantly increased. The PCS and MCS of the SF-12 health survey questionnaire had significantly increased and the SNOT questionnaire score had significantly decreased. The scientific documentation of the impact of Hatha Yoga on the airway resistances can be an eye opener in the management of several other diseases of the airways.