Maximal respiratory pressures of healthy children: comparison between obtained and predicted values.

Objective: To compare maximal inspiratory and expiratory pressures (PImax and PEmax, respectively) obtained in Brazilian children who are healthy with reference and predicted values from previous studies.

Methods: Respiratory muscle strength of 144 children (63 boys), aged 7 to 11 years, was assessed. A digital manovacuometer was used to measure PImax and PEmax from residual volume and total lung capacity, respectively. Children were assessed in the sitting position while wearing a nose clip.

Results: Mean values of PImax for boys and girls were 81.6 ± 20.2 and 66.1 ± 19.5 cmH2O, respectively. Mean values of PEmax in boys and girls were 95.6 ± 21.1 and 78.9 ± 19.7 cmH2O, respectively.

Conclusions: Published reference values demonstrated a wide diversity across age groups studied, and published equations were not successful in predicting maximal respiratory pressures; thus, the assessment of respiratory muscle strength of children should consider the minimization of ethnic and methodological differences.