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Updated: Jun 27, 2025

Conducting Respiratory Oscillometry in an Outpatient Setting
Published on: April 8, 2022
Impulse oscillometry in the diagnosis of cough variant asthma in children
Chunyu Tian1, Shiqiu Xiong1, Shuo Li1
1Department of Allergy, Children's Hospital Affiliated with the Capital Institute of Pediatrics, No.2 Yabao Road, Chaoyang District, Beijing, 100020, China.
Insights
Impulse oscillometry (IOS) can help diagnose cough variant asthma (CVA) in children. Combining IOS parameters before and after bronchodilation significantly improves diagnostic accuracy for CVA.
Area of Science:
- Pediatric Pulmonology
- Respiratory Diagnostics
- Asthma Research
Background:
- Cough variant asthma (CVA) is a common cause of chronic cough in children, posing diagnostic challenges.
- Accurate diagnosis of CVA is crucial for effective management and treatment in pediatric populations.
Purpose of the Study:
- To evaluate the diagnostic utility of impulse oscillometry (IOS) pulmonary function tests in children with CVA.
- To assess the effectiveness of bronchodilation (BD) tests in conjunction with IOS for CVA diagnosis.
Main Methods:
- Children aged 4-12 with CVA underwent IOS and BD tests; a control group of healthy children was included.
- Pre- and post-bronchodilation IOS parameters were recorded and analyzed.
- Receiver operating characteristic (ROC) curves and area under the curve (AUC) were used to determine diagnostic discriminatory potential.
Main Results:
- Children with CVA showed significantly different baseline IOS parameters compared to controls.
- IOS parameters improved significantly after bronchodilation in the CVA group.
- Combinations of pre-BD and BD-induced changes in IOS parameters (pre-Z5%pred+△Z5% and pre-R5%pred+△R5%) yielded the highest diagnostic accuracy (AUC 0.920 and 0.898).
Conclusions:
- Children with CVA exhibit distinct IOS parameter profiles compared to healthy children.
- Changes in IOS parameters following bronchodilation offer valuable diagnostic insights for CVA.
- Combining multiple IOS parameters enhances the accuracy of CVA diagnosis in pediatric patients.
Background:
Cough variant asthma (CVA) is one of the most common causes of chronic cough in children worldwide. The diagnosis of CVA in children remains challenging. This study aimed to assess the diagnostic utility of impulse oscillometry (IOS) pulmonary function in children with CVA.
Methods:
This study included children aged 4 to 12 years diagnosed with CVA who underwent IOS pulmonary function and bronchodilation (BD) tests. A control group of healthy children was matched. Pre- and post-BD IOS parameters were recorded and presented as mean ± standard deviation or median. Receiver operating characteristic (ROC) curves were plotted, and the area under the curve (AUC) was calculated to evaluate the discriminatory potential of the IOS parameters for diagnosing CVA.
Results:
A total of 180 patients with CVA and 65 control subjects were included. The baseline IOS parameters in the CVA group, except X5%pred, were significantly greater compared to the control group. After inhalation of salbutamol sulfate, all IOS parameters improved significantly in the CVA group. However, Z5%pred, R5%pred, and R20%pred remained greater in the CVA group compared to the control group. The improvement rates of IOS parameters in the CVA group significantly surpassed those in the control group. The ROC curve results for pre-BD IOS parameters and the improvement rate during the BD test showed that the combinations of pre-Z5%pred+△Z5% and pre-R5%pred+△R5% achieved the highest AUC value of 0.920 and 0.898, respectively. The AUC values of these combined parameters surpassed those of individual ones.
Conclusions:
This study highlights that children with CVA exhibit greater IOS parameters compared to healthy children. The changes in IOS parameters during the BD test provided valuable diagnostic information for CVA, and the combination of various parameters can help pediatricians accurately identify CVA in children.
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