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Fractional Exhaled Nitric Oxide (fractional + exhaled_nitric_oxide)
Selected AbstractsExhaled Nitric Oxide Levels during Acute Asthma ExacerbationACADEMIC EMERGENCY MEDICINE, Issue 7 2005Michelle Gill MD Abstract Objectives: Fractional exhaled nitric oxide (FENO) has been shown in laboratory settings and trials of patients with stable asthma to correlate with the degree of airway inflammation. The authors hypothesized that the technique of measuring FENO would be reproducible in the setting of acute asthma in the emergency department (ED) and that the FENO results during ED visits would potentially predict disposition, predict relapse following discharge, and correlate with the National Institutes of Health (NIH) asthma severity scale and peak expiratory flow measurements. Methods: The authors prospectively measured FENO in a convenience sample of ED patients with acute exacerbations of asthma, both at the earliest possible opportunity and then one hour later. Each assessment point included triplicate measurements to assess reproducibility. The authors also performed spirometry and classified asthma severity using the NIH asthma severity scale. Discharged patients were contacted in 72 hours to determine whether their asthma had relapsed. Results: The authors discontinued the trial (n= 53) after a planned interim analysis demonstrated reproducibility (coefficient of variation, 15%) substantially worse than our a priori threshold for precision (4%). There was no association between FENO response and corresponding changes in spirometry or clinical scores. Areas under the receiver operating characteristic curves for the prediction of hospitalization and relapse were poor (0.579 and 0.713, respectively). Conclusions: FENO measurements in ED patients with acute asthma exacerbations were poorly reproducible and did not correlate with standard measures of asthma severity. These results suggest that using existing technology, FENO is not a useful marker for assessing severity, response to treatment, or disposition of acute asthmatic patients in the ED. [source] An economic evaluation of NIOX MINO airway inflammation monitor in the United KingdomALLERGY, Issue 3 2009D. Price Background:, Fractional exhaled nitric oxide (FENO), a marker of eosinophilic airway inflammation, is easily measured by noninvasive means. The objective of this study was to determine the cost-effectiveness of FENO measurement using a hand-held monitor (NIOX MINO), at a reimbursement price of £23, for asthma diagnosis and management in the UK. Methods:, We constructed two decision trees to compare FENO measurement with standard diagnostic testing and guideline recommendations for management. For asthma diagnosis, we compared FENO measurement with lung function and reversibility testing, bronchial provocation and sputum eosinophil count. For asthma management, we evaluated the impact on asthma control, including inhaled corticosteroid use, exacerbations and hospitalizations, of monitoring with FENO measurement vs symptoms and lung function as in standard care. Resource use and health outcomes were evaluated over a 1-year time frame. Direct costs were calculated from a UK health-care payer perspective (2005 £). Results:, An asthma diagnosis using FENO measurement cost £43 less per patient as compared with standard diagnostic tests. Asthma management using FENO measurement instead of lung function testing resulted in annual cost-savings of £341 and 0.06 quality-adjusted life-years gained for patients with mild to severe asthma and cost-savings of £554 and 0.004 quality-adjusted life-years gained for those with moderate to severe asthma. Conclusions:, Asthma diagnosis based on FENO measurement with NIOX MINO alone is less costly and more accurate than standard diagnostic methods. Asthma management based on FENO measurement is less costly than asthma management based on standard guidelines and provides similar health benefits. [source] Value of fractional exhaled nitric oxide (FENO) for the diagnosis of pulmonary involvement due to inflammatory bowel diseaseINFLAMMATORY BOWEL DISEASES, Issue 4 2010Ezgi Ozyilmaz MD Abstract Background: Pulmonary involvement due to inflammatory bowel disease (IBD) is frequent when evaluating a patient with IBD and pulmonary involvement remains complicated. Most of the patients are asymptomatic and the methods used are mostly invasive or expensive procedures. The aim of this prospective study is to evaluate the value of the fractional exhaled nitric oxide (FENO) level for the diagnosis of pulmonary involvement due to IBD and to investigate any correlation between FENO level and disease activity. Methods: Thirty-three nonsmoker patients with IBD (25 ulcerative colitis [UC] and 8 Crohn's Disease [CD]) who were free of corticosteroid treatment and 25 healthy subjects as a control group were enrolled in this study. All patients with IBD were investigated for pulmonary involvement with medical history, physical examination, chest roentgenogram, oxygen saturation, blood eosinophil levels, pulmonary function tests (PFTs), high-resolution computed tomography (HRCT), and FENO level. Results: Pulmonary involvement was established in 15 patients (45.5%) with IBD. The FENO level was higher in patients with pulmonary involvement than without pulmonary involvement and healthy controls independent from the pulmonary symptoms, eosinophil count, duration of disease, activity of disease, and surgery history (FENO: 32 ± 20; 24 ± 8; 14 ± 8 ppb, respectively) (P < 0.05). In addition, diffusion capacity (DLCO) was found to be significantly lower in patients with CD compared with UC (P < 0.05). Conclusions: This study showed that an increased FENO level may be used for identifying patients with IBD who need further pulmonary evaluation. Inflamm Bowel Dis 2009 [source] Reliability of a new hand-held device for the measurement of exhaled nitric oxideALLERGY, Issue 10 2007B. Khalili Background:, Given the importance of airway inflammation in asthma, there has been an effort to incorporate inflammatory markers into its management. Measurement of fractional exhaled nitric oxide (FeNO) is a noninvasive marker of airway inflammation; however, the use of the available FeNO analyzer is limited by several factors including its cost and lack of transportability. The aim of this study was to compare the performance of a new hand-held FeNO measuring device (NIOX MINO) to the current clinical standard , the chemiluminescence FeNO analyzer (NIOX). Methods:, Subjects 6 years and older presenting to an allergy and asthma clinic underwent FeNO evaluation by NIOX and each of three NIOX MINOs. The mean of two acceptable measurements from the NIOX and the first approved measurement from each NIOX MINO were used for analysis. Results:, One hundred ten patients aged 6,86 years completed the study. Intrasubject FeNO levels obtained by each of the three NIOX MINOs revealed no significant difference between the measurements (P = 0.59). There was a very strong correlation between FeNO measurements by NIOX and by NIOX MINO (r = 0.98, P < 0.0001). The mean intrasubject FeNO difference between NIOX and NIOX MINO was ,0.5 p.p.b. which was not statistically significantly different from zero (P = 0.21). Conclusions:, Fractional exhaled nitric oxide measurements by the NIOX MINO showed a strong correlation and a high degree of agreement with the current standard stationary device. The NIOX MINO may be reliably used in clinical practice. [source] Comparability of a hand-held nitric oxide analyser with online and offline chemiluminescence-based nitric oxide measurementPEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 7 2009Barbara Schiller Practicability is crucial for successful implementation of fractional exhaled nitric oxide (FeNO) measurement into asthma management. The study aimed at comparing a conventional chemiluminescence NO analyser (EcoMedics®) with a hand-held device (NIOX MINO®) and offline FeNO measurement using a commercially available system in an unselected cohort of children aged 6,16 yr. A secondary objective was to confirm FeNO stability over time in 15 samples from adult volunteers obtained using the offline system. Sixty-six children (mean ± s.d. age 11.8 ± 3.0 yr) underwent single breath FeNO measurement in triplets with each device. Offline collected FeNO was measured after offline breath collection into a Mylar balloon and subsequent analysis using the chemiluminescence NO analyser. Variability and between-method agreement were assessed, and stability over time within the Mylar balloons was tested by repeated hourly measurements. FeNO levels ranged from 2 to 113 p.p.b. Intra-class correlation was excellent (r = 0.98, p < 0.001 for each pair). Bland,Altman plots and back-transformation of logarithmic mean differences revealed fair agreement between methods. Stability over time was confirmed over 10 h both at room temperature and when stored under cooling conditions. FeNO values obtained using the chemiluminescence NO analyser, the portable NIOX MINO® system and the offline collection technique show between-method agreement within clinically acceptable range. [source] Association among lung function, exhaled nitric oxide, and the CAN questionnaire to assess asthma control in children,PEDIATRIC PULMONOLOGY, Issue 5 2010O. Sardón-Prado MD Abstract Background The aim of this study was to investigate the association among a validated symptom-based questionnaire for asthma control in children (CAN), forced expiratory volume in 1,sec (FEV1), and fractional exhaled nitric oxide (FENO). Methods Observational cross-sectional study was performed in a consecutive sample of asthmatic children aged between 7 and 14 years old from December 2007 to February 2008. FENO was measured with a portable electrochemical analyzer and forced spirometry was performed according to American Thoracic Society/European Respiratory Society. The CAN questionnaire was completed by the parents (aged <9 years old) or by the children (,9 years old). The strength of the association among FEV1, FENO, and CAN questionnaire was studied using Spearman's rho, and the degree of agreement for asthma control among FEV1, FENO, and CAN questionnaire, with classification of these variables according to values of normality, was studied using Pearson's ,2 test and Cohen's kappa (KC). Results We studied 268 children, mean age 9.7,±,2.1 years. Significant correlations were found between FENO and CAN (r,=,0.2), between FEV1 and CAN (r,=,,0.3), and between FENO and FEV1 (r,=,,0.12). On classifying the variables according to values of normality, no agreement was found to establish the degree of asthma control between FENO and CAN (KC,=,0.18, ,2 Pearson,=,9.63); between FEV1 and CAN (KC,=,0.29, ,2,=,38.5); or between FENO and FEV1 (KC,=,0.07, ,2,=,4.9). Conclusions The association among the three measurement instruments used to assess asthma control (FEV1, FENO, and CAN) was weak. These are instruments that quantify variables that influence asthma in different ways, in this sense, none can be used instead of another in asthma management although they are complementary. Pediatr Pulmonol. 2010; 45:434,439. © 2010 Wiley-Liss, Inc. [source] Methodological issues related to exhaled nitric oxide measurement in children aged four to six yearsPEDIATRIC PULMONOLOGY, Issue 2 2005Edward Napier MBBS Abstract This study was designed to test five methodological issues related to measurement of fractional exhaled nitric oxide (FENO) in children aged 4,6 years using commercially available apparatus. Participants attended two randomly selected schools. A respiratory questionnaire was completed. Measurements of FENO were made on successive days, using a NIOX® analyzer employing standard or modified methodologies. Ninety-one children participated in the study (mean age, 5.3 years; 46 boys). Using a standard methodology (n,=,61), FENO was successfully measured in 28 (46%) children, 1/12 aged 4 years, 12/25 aged 5 years, and 15/24 aged 6 years (trend test P,=,0.01). On the first assessment, FENO could be determined in more boys than girls (64% vs. 30%, respectively, P,=,0.008), but this gender difference was not apparent on the second assessment. Exhaled NO was reproducible over a 24-hr period; the mean difference between repeated measurements of natural log (ln) FENO was 0.016 parts per billion (ppb) (95% confidence limits, ,0.479, 0.511), n,=,20. Data from 35 assessments showed that values of FENO did not alter over nine individual, successive measurements. Use of a modified methodology in 30 children increased success in obtaining FENO, but these values were unreliable. In conclusion, measurements of FENO can be obtained in the majority of 5- and 6-year-old but not 4-year-old children. Exhaled NO measurements were reproducible over a 24-hr interval, and did not change over up to nine expiratory maneuvers in these young children. Pediatr Pulmonol. 2005; 40:97,104. © 2005 Wiley-Liss, Inc. [source] Asthma Control Test correlates well with the treatment decisions made by asthma specialistsRESPIROLOGY, Issue 4 2009Fanny W.S. KO ABSTRACT Background and objective: Poor assessment of asthma control results in suboptimal treatment. Identifying parameters that accurately assess control will benefit treatment decisions. The Asthma Control Test (ACT) is a five-item questionnaire for the assessment of asthma control. This study evaluated its correlation with the treatment decisions made by asthma specialists in an outpatient clinic setting, and compared its performance with other conventional parameters including spirometry, PEF rate (PEFR), fractional exhaled nitric oxide (FeNO) and BHR. Methods: The 383 (122 men) study subjects completed a 1-month diary on symptoms and PEFR before the assessment. All subjects then completed the ACT together with same-day spirometry and FeNO measurement. BHR to methacholine was performed in 73 subjects in the week before assessment. Asthma specialists, blinded to the results of the ACT, FeNO and BHR (but not spirometry and PEFR), assessed the patients' level of control according to the 2006 version of the Global Initiative for Asthma guidelines and made appropriate treatment decision. Results: The group mean (SD) age was 46.1 (13.4) years with pre-bronchodilator FEV1 84.72 (20.81) % predicted. Receiver operating characteristic (ROC) curve analysis found that an ACT score of ,20 best correlated with uncontrolled asthma (area under curve (AUC) = 0.76) with a sensitivity of 70.5%, specificity 76.0%, positive predictive value 76.2% and negative predictive value 70.2% for predicting step-up of asthma therapy. On ROC analysis, the ACT score had the highest AUC (0.81 (P < 0.001)) for changing asthma therapy when compared with FeNO, spirometry, PEFR and BHR parameters Conclusions: The ACT correlated better with treatment decisions made by asthma specialists than spirometry, PEFR and FeNO. [source] Using fractional exhaled nitric oxide to guide asthma therapy: design and methodological issues for ASthma TReatment ALgorithm studiesCLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2009P. G. Gibson Prof. Summary Background Current asthma guidelines recommend treatment based on the assessment of asthma control using symptoms and lung function. Noninvasive markers are an attractive way to modify therapy since they offer improvedselection of active treatment(s) based on individual response, and improvedtitration of treatment using markers that are better related to treatment outcomes. Aims: To review the methodological and design features of noninvasive marker studies in asthma. Methods Systematic assessment of published randomized trials of asthma therapy guided by fraction of exhaled nitric oxide(FENO). Results FENO has appeal as a marker to adjust asthma therapy since it is readily measured, gives reproducible results, and is responsive to changes in inhaled corticosteroid doses. However, the five randomised trials of FENO guided therapy have had mixed results. This may be because there are specific design and methodological issues that need to be addressed in the conduct of ASthma TReatment ALgorithm(ASTRAL) studies. There needs to be a clear dose response relationship for the active drugs used and the outcomes measured. The algorithm decision points should be based on outcomes in the population of interest rather than the range of values in healthy people, and the algorithm used needs to provide a sufficiently different result to clinical decision making in order for there to be any discernible benefit. A new metric is required to assess the algorithm performance, and the discordance:concordance(DC) ratio can assist with this. Conclusion Incorporating these design features into future FENO studies should improve the study performance and aid in obtaining a better estimate of the value of FENO guided asthma therapy. [source] | ||||||||||||||||||||||