scholarly journals Bronchodilator Response Assessment of the Small Airways Obstructive Pattern

2017 ◽  
Vol 11 (1) ◽  
pp. 47-53 ◽  
Author(s):  
Plamen Bokov ◽  
Clémence Martin ◽  
Sémia Graba ◽  
Karine Gillet-Juvin ◽  
Mohamed Essalhi ◽  
...  
Keyword(s):  
Lower Limit ◽  
Pulmonary Function Tests ◽  
Response Assessment ◽  
Small Airways ◽  
Impulse Oscillometry ◽  
Bronchodilator Response ◽  
Airway Assessment ◽  
The Difference ◽  
Low Sensitivity ◽  
Lower Limit Of Normal

Background: A concomitant decrease in FEV1 and FVC with normal FEV1/FVC ratio and TLC defines small airways obstructive pattern (SAOP) and constitutes a classic pitfall of pulmonary-function-tests interpretation. Objective: To evaluate the prevalence of flow- (FEV1 increase≥12% and 200 mL), volume- (FVC or inspiratory capacity [IC] increase≥12% and 200 mL), flow and volume-, and non-response to bronchodilation in patients with SAOP. An additional objective was to assess whether impulse oscillometry (IOS) parameters allow the diagnosis of SAOP and its reversibility. Methods: Fifty consecutive adult patients with SAOP (FEV1 and FVC < lower limit of normal, FEV1/FVC and TLC > lower limit of normal) diagnosed on spirometry and plethysmography underwent the assessment of reversibility (400 µg salbutamol) on FEV1, FVC, IC and IOS parameters. Results: The diseases most frequently associated with SAOP were COPD and asthma (26 and 15 patients, respectively). Six patients were flow-responders, 20 were volume-responders, 9 were flow and volume-responders and 15 patients were non-responders. Overall, 26 patients had a significant improvement of IC, and 35 / 50 (70%, 95%CI: 57-83) exhibited a significant bronchodilator response. The difference between Rrs5Hz and Rrs20Hz was increased in 28/50 patients (56%, 95%CI: 42-70 with value higher than upper limit of normal) and its decrease after bronchodilator significantly correlated to FEV1 increase only, suggesting proximal airway assessment. Conclusion: A significant reversibility, mainly assessed on IC increase, is frequent in Small Airways Obstructive Pattern. Impulse oscillometry is of limited value in this context because of its low sensitivity.

scholarly journals Relationship between impulse oscillometry system and conventional lung function test for diagnosis of bronchiolitis obliterans in children

2021 ◽  
Author(s):  
Hye Jin Lee ◽  
Kyunghoon Kim ◽  
Seong koo Kim ◽  
Jae Wook Lee ◽  
Jong-Seo Yoon ◽  
...  
Keyword(s):  
Lung Function ◽  
Test Performance ◽  
Bronchiolitis Obliterans ◽  
Diagnostic Performance ◽  
Pulmonary Function Tests ◽  
Lung Function Test ◽  
Receiver Operating Curve ◽  
Small Airways ◽  
Impulse Oscillometry ◽  
Function Test

Background: Functional assessment of small airways in young children with bronchiolitis obliterans (BO) is challenging due to their relative inaccessibility and the generally poor lung function test performance of these patients. We analyze the correlation between impulse oscillometry (IOS), spirometry, and plethysmographic parameters in pediatric BO patients. Methods: A total of 89 IOS assessments of pediatric BO patients or children without lung disease were included, and the relationship between pulmonary function tests (PFTs) and diagnostic performance were analyzed. Results: R5, R5-20, X5, and AX were statistically significantly worse in the BO group. In Spearman’s correlation analysis, AX and R5 showed the strongest correlation with conventional PFT parameters, and AX was the variable with the highest relative correlation with FEV1, FEF25-75%, and both measures of plethysmographic resistance. Receiver operating curve analysis highlighted AX and Raw% pred as the most optimal parameters for BO diagnostic performance with areas under curve of 0.811 and 0.827, respectively. Conclusion: The AX and R5 parameters can be useful in identifying the severity of airway obstruction in children with BO, and IOS more generally can accurately detect pathological obliteration of small airways in pediatric BO patients.

scholarly journals Impulse Oscillometry May Be Useful in Evaluation of Bronchiectasis Severity and Prediction of Airway Reversibility.

2021 ◽  
Author(s):  
Cuiyan Tan ◽  
Donghai Ma ◽  
Kongqiu Wang ◽  
Changli Tu ◽  
Meizhu Chen ◽  
...  
Keyword(s):  
Airway Resistance ◽  
Severe Disease ◽  
Peripheral Resistance ◽  
Roc Curves ◽  
Small Airways ◽  
Impulse Oscillometry ◽  
Airway Diseases ◽  
The Difference ◽  
Obstructive Airway Diseases ◽  
Airway Reversibility

Abstract BackgroundImpulse oscillometry (IOS) can be used to evaluateairway impedance in patients with obstructive airway diseases. Previous studies have demonstrated that IOS parameters differ betweenbronchiectasis patients and healthy controls. This study aims to explore the usefulness of IOS in assessing disease severity and airway reversibility in bronchiectasis.MethodSeventy-four patients with non-cystic fibrosis bronchiectasis who visited our Respiratory Medicine outpatient clinic were consecutively recruited. Spirometry, plethysmography and IOS tests were performed. Patients were stratified into mild, moderate and severe disease according to Reiff, Bhalla, BSI, FACED, and BRICS scores. Airway reversibility was measured by bronchodilation test (BDT) and the result was classified as positive or negative.. ROC curves of IOS parameters was used to assess the usefulness of IOS parameters in predicting airway reversibility. Correlations between the IOS, spirometric lung function and bronchiectasis severity parameters were analysed.ResultsMany IOS parameters, such as airway resistance at 5Hz (R5), small airways resistance (R5–R20), total airway reactance (X5), resonance frequency (Fres), total airway impedance at 5Hz (Z5), and peripheral resistance (Rp) increased with increased bronchiectasis severity according to the FACED, BSI and Reiff scores. Large airway resistance (R20) and central resistance (Rc) were not significantly different among groups with differentbronchiectasis severity. The difference between R5 and R20 (R5-R20) showed 81.0% sensitivity, and 69.8%specificity in predicting the airway reversibility in bronchiectasis with AUC of 0.794 (95%CI, 0.672-0.915).ConclusionIOS measurements are useful indicators of bronchiectasis severity and may be useful for predicting the airway reversibility.

Increased prevalence of small airways dysfunction in patients with systemic sclerosis as determined by impulse oscillometry

Rheumatology ◽  
2019 ◽  
Author(s):  
Martina Bonifazi ◽  
Nicola Sverzellati ◽  
Eva Negri ◽  
Giovanni Pomponio ◽  
Valeria Seletti ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Low Frequency ◽  
Small Airways ◽  
Impulse Oscillometry ◽  
Therapeutic Implications ◽  
Radiological Features ◽  
Related Quality ◽  
St George's Respiratory Questionnaire ◽  
The Difference

Abstract Objectives The prevalence and clinical implications of small airways involvement in SSc are still to be fully elucidated. The goal of the present work is to assess the prevalence of small airways dysfunction by impulse oscillometry and to determine whether it correlates with selected disease-related features and respiratory-related quality of life. Methods Ninety-four SSc patients and 93 healthy controls were studied by impulse oscillometry measurements. Small airways dysfunction was defined as the difference between resistance at low frequency, i.e. 5 Hz, and resistance at high frequency, i.e. 20 Hz, termed ‘R5-R20’, ⩾0.07 kPa/l/s. The St George’s Respiratory Questionnaire was used to measure health impairment in SSc patients. Radiological features of small airways disease and parenchymal abnormalities on high resolution CT chest scans were jointly assessed by two thoracic radiologists. Results Small airways dysfunction was present in 21.5% of the SSc patient cohort, with a prevalence almost 5-fold higher compared with controls, and it was significantly associated with worse respiratory-related quality of life. Radiological features consistent with small airways abnormalities were detected in 25% of SSc patients, mostly in the absence of interstitial lung changes. Combining functional and radiological evaluations, one-third of the SSc cohort showed at least one feature of small airways involvement, which was associated with the lcSSc phenotype and with longer disease duration. Conclusion The current study strengthens the hypothesis that small airway dysfunction might be a feature of SSc-related lung involvement, providing the first data on its significant impact on respiratory-related quality of life. A full assessment of lung function in SSc patients should include impulse oscillometry as a complementary technique, due to potential clinical and therapeutic implications.

The Effect of Using the Lower Limit of Normal 2.5 in Pulmonary Aeromedical Assessments

2020 ◽  
Vol 91 (8) ◽  
pp. 636-640 ◽  
Author(s):  
Yara Q. Wingelaar-Jagt ◽  
Thijs T. Wingelaar ◽  
Metin Bülbül ◽  
Pijke P. vd Bergh ◽  
Erik Frijters ◽  
...  
Keyword(s):  
Lower Limit ◽  
Reference Values ◽  
Pulmonary Function Tests ◽  
Fixed Ratio ◽  
Forced Expiratory Volume ◽  
Chi Squared ◽  
Group 2 ◽  
The Impact ◽  
Lower Limit Of Normal ◽  
Group 1

INTRODUCTION: Many regulations for aeromedical assessments state that a ratio between forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) of < 0.7 should be evaluated by a pulmonary specialist. The Global Lung Initiative (GLI) reference values introduced the lower limit of normal (LLN 2.5), in which the lowest 2.5% of the population is regarded as abnormal, instead of a fixed ratio. This study assesses the impact of adopting GLI reference values on aeromedical evaluation and referrals.METHODS: The Royal Netherlands Air Force performed 7492 aeromedical assessments between February 2012 and April 2017. Cases with FEV1/FVC < 0.7 from three groups were selected: 1) men < 25 yr; 2) men > 40 yr; and 3) women, with twice as many matched controls. Pearson's Chi-squared and Fisher’s exact tests were used to analyze the data.RESULTS: From the database, 23 (group 1), 62 (group 2), and 7 (group 3) cases were selected, with 184 controls. Respectively, 17%, 84%, and 29% would not be referred using the GLI. In the controls, this would lead to one additional referral (group 1). Qualitative analysis of the cases who would not be referred using the GLI showed that no significant diagnoses would have been missed.DISCUSSION: Using the GLI LLN 2.5 reference values for pulmonary function tests leads to significantly fewer referrals to a pulmonary specialist without missing relevant pulmonary pathology in our aircrew. This would reduce resources spent on the assessment of aircrew without compromising flight safety.Wingelaar-Jagt YQ, Wingelaar TT, Bülbül M, vd Bergh PP, Frijters E, Staudt E. The effect of using the lower limit of normal 2.5 in pulmonary aeromedical assessments. Aerosp Med Hum Perform. 2020; 91(8):636–640.

Factor XII Determinations in the Presence and Absence of Phospholipid Antibodies

1998 ◽  
Vol 79 (01) ◽  
pp. 87-90 ◽  
Author(s):  
D. W. Jones ◽  
M. Winter ◽  
M. J. Gallimore
Keyword(s):  
Lower Limit ◽  
Lupus Anticoagulant ◽  
Factor Xii ◽  
Chromogenic Substrate ◽  
Plasma Samples ◽  
Presence And Absence ◽  
Lower Limit Of Normal

SummaryFactor XII (FXII) levels were determined in plasma samples from 29 normal donors, 10 patients with inherited FXII deficiency (all lupus anticoagulant [LA] negative) and 67 LA positive patients, using clotting (FXIIct), chromogenic substrate (FXIIcs) and immunochemical (FXIIag) assays. Excellent correlations were obtained in the three FXII assays with the LA negative samples and between the FXIIcs and FXIIag assays in the LA positive samples. Correlations between both the FXIIcs and FXIIag with FXIIct in the LA positive patients were poor. Of 67 LA positive samples studied, 25 (37.3%) showed lower values in the FXIIct assay; 13 (19.4%) of these patients were pseudo FXII deficient with values of FXII below the lower limit of normal.These results indicate that a diagnosis of FXII deficiency can be made inappropriately in the presence of phospholipid antibodies and that such a diagnosis should not be made by FXIIct assay alone.

VARIABLE BRONCHODILATOR RESPONSE IN 6867 PULMONARY FUNCTION TESTS

CHEST Journal ◽  
2007 ◽  
Vol 132 (4) ◽  
pp. 613B
Author(s):  
Tarun Madappa ◽  
Jeffrey C. Nascimento ◽  
Mir O. Ali ◽  
Steve Lowenstein ◽  
Murray Rogers ◽  
...  
Keyword(s):  
Pulmonary Function ◽  
Pulmonary Function Tests ◽  
Bronchodilator Response ◽  
Function Tests

Agreement Between Fixed-Ratio and Lower Limit of Normal Spirometry Interpretation Protocols Decreases With Age

2013 ◽  
Vol 55 (7) ◽  
pp. 802-808 ◽  
Author(s):  
Marek A. Mikulski ◽  
Alicia K. Gerke ◽  
Spencer Lourens ◽  
Thomas Czeczok ◽  
Nancy L. Sprince ◽  
...  
Keyword(s):  
Lower Limit ◽  
Fixed Ratio ◽  
Lower Limit Of Normal

scholarly journals Markers of Perioperative Bowel Complications in Colorectal Surgery Patients

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Radomír Hyšpler ◽  
Alena Tichá ◽  
Milan Kaška ◽  
Lenka Žaloudková ◽  
Lenka Plíšková ◽  
...  
Keyword(s):  
Colorectal Surgery ◽  
Anastomotic Leakage ◽  
Intestinal Resection ◽  
Specific Marker ◽  
Exhaled Breath ◽  
Fatty Acid Binding ◽  
Gastrointestinal Complications ◽  
Reactive Protein ◽  
The Difference ◽  
Low Sensitivity

Colorectal cancer is a clinical condition whose treatment often involves intestinal resection. Such treatment frequently results in two major gastrointestinal complications after surgery: anastomotic leakage and prolonged ileus. Anastomotic leakage is a serious complication which, more often than not, is diagnosed late; to date, C-reactive protein is the only available diagnostic marker. A monocentric, prospective, open case-control study was performed in patients(n=117)undergoing colorectal surgery. Intestinal fatty acid binding protein (i-FABP), citrulline, D-lactate, exhaled hydrogen,Escherichia coligenomic DNA, and ischemia modified albumin (IMA) were determined preoperatively, postoperatively, and on the following four consecutive days. Bacterial DNA was not detected in any sample, and i-FABP and D-lactate lacked any distinct potential to detect postoperative bowel complications. Exhaled breath hydrogen content showed unacceptably low sensitivity. However, citrulline turned out to be a specific marker for prolonged ileus on postoperative days 3-4. Using a cut-off value of 20 μmol/L, a sensitivity and specificity of ~75% was achieved on postoperative day 4. IMA was found to be an efficient predictor of anastomosis leak by calculating the difference between preoperative and postoperative values. This test had 100% sensitivity and 80% specificity and 100% negative and 20% positive predictive value.

Evaluation of the Capillary Microhematocrit as a Screening Test for Anemia in Pediatric Office Practice

PEDIATRICS ◽  
1986 ◽  
Vol 78 (2) ◽  
pp. 206-209
Author(s):  
Paul C. Young ◽  
Barbara Hamill ◽  
Richard C. Wasserman ◽  
Joseph D. Dickerman
Keyword(s):  
Lower Limit ◽  
Screening Test ◽  
Pediatric Patients ◽  
Capillary Blood ◽  
White Children ◽  
Predictive Values ◽  
Special Skill ◽  
Capillary Sample ◽  
Sensitivity Specificity ◽  
Lower Limit Of Normal

The capillary microhematocrit test is widely used to screen pediatric patients for anemia. Recently, it has been suggested that this method produces spuriously elevated values compared with venous hematocrits measured by a Coulter electronic counter and might consequently fail to detect children who are truly anemic. To address this issue we studied 66 white children 9 months to 14 years of age whose capillary hematocrits were either below, equal to, or one or two points above the lower limit of normal for age. Venous specimens were obtained simultaneously with the capillary sample; hemoglobin, hematocrit, and mean corpuscular volume results were obtained using a Coulter electronic counter. Using published standards of venous hemoglobin, we determined the sensitivity, specificity, and predictive values of the capillary microhematocrit in this population of patients with low or borderline values. Twenty of the 66 patients had venous hemoglobin values less than the lower limit of normal. The sensitivity of the microhematocrit was 90.0%; the specificity was 43.5%. The predictive values for a normal (negative) hematocrit was 90.1%; the predictive value for a low (positive) hematocrit was 40.9%. We conclude that the microhematocrit method using capillary blood will miss very few patients with significantly low venous hemoglobin values and is thus an acceptable screening test for anemia. Because it does not require expensive equipment or special skill to obtain the specimen or perform the test, it is ideal for physicians' offices or nonhospital-based clinics.

scholarly journals The definition of anemia: what is the lower limit of normal of the blood hemoglobin concentration?

Blood ◽  
2006 ◽  
Vol 107 (5) ◽  
pp. 1747-1750 ◽  
Author(s):  
Ernest Beutler ◽  
Jill Waalen
Keyword(s):  
Normal Distribution ◽  
Lower Limit ◽  
Population Distribution ◽  
Hemoglobin Concentration ◽  
Blood Hemoglobin ◽  
Definition Of ◽  
Lower Limit Of Normal ◽  
Blood Hemoglobin Concentration

The diagnosis of anemia is an important aspect of the practice of hematology. The first step is to decide whether the patient is, in fact, anemic. Unless earlier blood counts are available, and they often are not, the physician must make his or her decision on the basis of the population distribution of hemoglobin values. How likely is it that the patient's hemoglobin value lies below the normal distribution; that is, “the lower limit”?

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