Comparative analysis of maximal respiratory pressures with the reference values of a healthy Spanish pediatric population

Background and aim: Maximal inspiratory and expiratory pressures (PImax/PEmax) are the most common test in clinical practice to assess respiratory muscle strength in different populations, even pediatrics. The main aim was to analyse to what extent the existing predictive equations for the maximal inspiratory and expiratory pressures in the Spanish pediatric population are reliable. Material and methods: Cross-sectional study in 9 autonomous communities that includes 164 healthy boys and girls aged 8-17 years. PImax/PEmax were performed using a digital manometer according to the standards of Spanish Society of Pulmonology and Thoracic Surgery (SEPAR). The results were compared with predictive equations proposed by Domènech-Clar et al. in 2003. Results: The sample consisted of 86 girls (11.5 ± 2.7 years; PImax: 93.8 ± 25 cmH₂O; PEmax: 115.1 ± 29 cmH₂O) and 78 boys (12.2 ± 2.8 years; PIM: 109 ± 29.2 cmH₂O; PEM: 132.7 ± 33.3 cmH₂O). Girls showed a significant difference between the observed and predictive values: 13.7 ± 26.4 cmH₂O (P < .001) for PImax and 14.9 ± 30.1 cmH₂O (P < .001) for PEmax. A significant difference was also observed for boys between observed and estimated PImax: 9.1 ± 28.5 cmH₂O (P = .006), without significant differences for PEmax. Conclusions: The predicted values from the available predictive equations for PImax and PEmax in the Spanish pediatric population differ significantly from the obtained values. The results of this study highlight the need of new reference equations in order to get representative values for Spanish children.