Paeds Vivas · respiratory-sleep-and-airway
Spirometry and paediatric pulmonary-function testing — branching viva
Branching viva from the definition of spirometry and the FEV1, FVC and ratio through the physiology of flow limitation, the obstructive and restrictive patterns, bronchodilator reversibility, the Global Lung Function Initiative z-score interpretation that has replaced fixed cut-offs, and the quality and safety of testing in children.
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Study tools
Target exams
RACP DWEMRCPCH ClinicalRCPCH Progress+
Prompt
You are the paediatric registrar in a respiratory function laboratory. The consultant asks you to talk through spirometry from first principles: what it measures, how you tell obstruction from restriction, how you test and read a bronchodilator response, how you decide what is normal, and how you keep the test safe and valid in children.
Station opening
Examiner: "Tell me what spirometry measures and the three values you take from it." [1]
Strong candidate (must-hit)
- Explains that spirometry records a single maximal forced expiration and yields the forced vital capacity (the total volume exhaled), the forced expiratory volume in one second (the volume exhaled in the first second), and their ratio, which reflects how fast the lungs empty; adds that the effort is displayed as a flow-volume loop whose shape carries diagnostic information beyond the numbers. [1] [6]
Weak candidate
- "It measures how good the lungs are and gives you a percentage of normal." [2]
References6ShowHide
- [1]Graham BL; Steenbruggen I; Miller MR; Barjaktarevic IZ; Cooper BG; Hall GL; et al Standardization of Spirometry 2019 Update. An Official American Thoracic Society and European Respiratory Society Technical Statement. Am J Respir Crit Care Med, 2019.PMID 31613151
- [2]Stanojevic S; Kaminsky DA; Miller MR; Thompson B; Aliverti A; Barjaktarevic I; et al ERS/ATS technical standard on interpretive strategies for routine lung function tests. Eur Respir J, 2022.PMID 34949706
- [3]Quanjer PH; Stanojevic S; Cole TJ; Baur X; Hall GL; Culver BH; et al Multi-ethnic reference values for spirometry for the 3-95-yr age range: the global lung function 2012 equations. Eur Respir J, 2012.PMID 22743675
- [6]Pellegrino R; Viegi G; Brusasco V; Crapo RO; Burgos F; Casaburi R; et al Interpretative strategies for lung function tests. Eur Respir J, 2005.PMID 16264058
- [9]Hall GL; Filipow N; Ruppel G; Okitika T; Thompson B; Kirkby J; et al Official ERS technical standard: Global Lung Function Initiative reference values for static lung volumes in individuals of European ancestry. Eur Respir J, 2021.PMID 33707167
- [10]Gaillard EA; Kuehni CE; Turner S; Goutaki M; Holden KA; de Jong CCM; et al European Respiratory Society clinical practice guidelines for the diagnosis of asthma in children aged 5-16 years. Eur Respir J, 2021.PMID 33863747