Related Experiment Videos
Methacholine challenge in preschool children: methacholine-induced wheeze versus transcutaneous oximetry
Insights
Tracheal/chest auscultation and arterial oxygen saturation monitoring are sensitive and safe endpoints for bronchial provocation tests in young children. Transcutaneous oxygen pressure monitoring showed unreliable results in preschool children during methacholine challenges.
Area of Science:
- Pediatric Pulmonology
- Respiratory Medicine
- Clinical Trials
Background:
- Bronchial provocation tests assess airway hyperresponsiveness.
- Wheezing and oxygen saturation are common outcome measures in pediatric respiratory assessments.
- Evaluating sensitive and safe endpoints is crucial for accurate pediatric testing.
Purpose of the Study:
- To compare the sensitivity and safety of tracheal/chest auscultation versus transcutaneous oximetry as endpoints for methacholine challenge tests in children under 4 years old.
- To determine the reliability of transcutaneous oxygen pressure (tcPO2) as a proxy for bronchial obstruction in this age group.
Main Methods:
- Seventy-two methacholine challenges were conducted in 39 children (<4 years) with recurrent wheeze.
- Continuous monitoring of arterial oxygen saturation (Sa,O2) and transcutaneous oxygen pressure (tcPO2).
- Test termination criteria included audible wheeze or Sa,O2 <91%.
Main Results:
- Wheeze or desaturation occurred at or below 8 mg x mL(-1) methacholine in all tests.
- Fifty-six tests (78%) were terminated due to wheeze, seven (10%) for decreased Sa,O2.
- Transcutaneous oxygen pressure showed erratic responses in some children, casting doubt on its reliability.
Conclusions:
- Tracheal/chest auscultation combined with Sa,O2 monitoring provides a sensitive and safe endpoint for bronchial challenges in preschool children.
- Transcutaneous oxygen pressure monitoring is less reliable for assessing bronchial obstruction in this pediatric population due to inconsistent responses.
Abstract:
Tracheal/chest auscultation for wheeze and transcutaneous oximetry have both been suggested as measures of outcome in bronchial provocation tests in young children. This study aimed to compare the sensitivity and safety of these two techniques as end-points for methacholine challenge in children aged <4 yrs. Seventy-two methacholine challenges were performed in 39 children aged <4 yrs with recurrent wheeze. Arterial oxygen saturation (Sa,O2) and transcutaneous oxygen pressure tcPO2 continuously, and the test was terminated when wheeze was heard or at Sa,O2 <91%. tcPO2 was not used as an end-point. Wheeze or desaturation occurred at < or =8 mg x mL(-1) methacholine in every test. One child had transient clinical cyanosis, but no other ill-effects were seen. Fifty-six tests (78%) were terminated for wheeze, seven (10%) for fall in Sa,O2 and nine (12%) showed simultaneous responses in both parameters. Twenty-eight tests (39%) contained a fall in tcPO2 >3 kPa but six of these also showed a significant rise. Fifty-three tests (75%) contained a fall in tcPO2 >15%, but 20 of these also showed a significant rise. Tracheal/chest auscultation with Sa,O2 monitoring is a sensitive and relatively safe end-point for bronchial challenges in preschool children. The erratic pattern of transcutaneous oxygen pressure response in some children casts doubt on its reliability as a proxy measure of bronchial obstruction.