Spirometric and exhaled nitric oxide reference values in preschool children from the community of Navarra.

BACKGROUND AND OBJECTIVE: Preschool children can perform quality, reproducible spirometric maneuvers, provided appropriate equipment is used and specially trained nursing staff training are available. However, use of spirometry for the diagnosis and follow-up of preschool children with respiratory diseases remains limited in clinical practice, because consensus on test quality and acceptability criteria and reference data are lacking. We initiated the present study with the aim of developing reference equations, since tables of normal values for this age group are not available in our area. PATIENTS AND METHODS: The study population comprised healthy preschool children in our community. Normal values for exhaled nitric oxide in this age range were assessed. Regression equations were constructed using univariate and multivariate models. RESULTS: A total of 114 healthy preschool children aged 3 to 6 years were enrolled. According to the criteria of the American Thoracic Society/European Respiratory Society, 60 children were able to perform acceptable and reproducible spirometric maneuvers. The best correlations were observed for the untransformed linear regression model that included height. The correlation coefficients for forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), and FEV0.5 were 0.89, 0.88, and 0.86, respectively. The regression equations for the calculation of reference values were as follows: FVC = -2.6 + 0.036 x height, cm FEV1 = -2.04 + 0.029 x height, cm FEV0.5 = -1.53 + 0.022 x height, cm. We obtained fraction of inhaled nitric oxygen (FeNO) values for 56 children. The mean (SD) value was 11 (4.9) ppb. CONCLUSIONS: Most preschool children in our area were able to perform quality spirometry maneuvers. We obtained regression equations that allowed us to calculate the reference ranges in our population and the distribution of normal FeNO values.

Spirometric and exhaled nitric oxide reference values in preschool children from the Community of Navarra

Background and Objective: Preschool children can perform quality, reproducible spirometric maneuvers, provided appropriate equipment is used and specially trained nursing staff training are available. However, use of spirometry for the diagnosis and follow-up of preschool children with respiratory diseases remains limited in clinical practice, because consensus on test quality and acceptability criteria and reference data are lacking. We initiated the present study with the aim of developing reference equations, since tables of normal values for this age group are not available in our area. Patients and Methods: The study population comprised healthy preschool children in our community. Normal values for exhaled nitric oxide in this age range were assessed. Regression equations were constructed using univariate and multivariate models. Results: A total of 114 healthy preschool children aged 3 to 6 years were enrolled. According to the criteria of the American Thoracic Society/ European Respiratory Society, 60 children were able to perform acceptable and reproducible spirometric maneuvers. The best correlations were observed for the untransformed linear regression model that included height. The correlation coefficients for forced vital capacity (FVC), forced expiratory volume in the first second (FEV 1 ), and FEV 0.5 were 0.89, 0.88, and 0.86, respectively. The regression equations for the calculation of reference values were as follows: FVC = -2.6 + 0.036 x height, cm FEV 1 = -2.04 + 0.029 x height, cm FEV 0.5 = -1.53 + 0.022 x height, cm We obtained fraction of inhaled nitric oxygen (FeNO) values for 56 children. The mean (SD) value was 11 (4.9) ppb. Conclusions: Most preschool children in our area were able to perform quality spirometry maneuvers. We obtained regression equations that allowed us to calculate the reference ranges in our population and the distribution of normal FeNO values (AU)

Antecedentes: Los niños preescolares pueden realizar maniobras espirométricas de calidad y reproducible, siempre y cuando se utilice un equipamiento adecuado y se disponga de personal de enfermería con entrenamiento específico para ello. Sin embargo su uso clínico en este rango de edad tanto en diagnóstico como en seguimiento de pacientes con enfermedades respiratorias sigue siendo muy escaso, por diversas razones. Entre otras se encuentran la falta de un consenso en los criterios de calidad y aceptabilidad de la prueba la escasez de datos de referencia. Objetivo y métodos: Debido a que no se disponía de tablas de valores normales para este rango de edad en nuestra área, se inició este estudio con el fin de obtener ecuaciones de referencia provenientes de una población de niños preescolares sanos de nuestra comunidad, aprovechando el esfuerzo para obtener también valores de normalidad de óxido nítrico en aire exhalado en este rango de edad. Para la obtención de las ecuaciones de regresión se utilizaron modelos uni y multivariantes. Resultados: Se incluyeron un total de 114 niños preescolares sanos con edades comprendidas entre los 3 y los 6 años. De ellos 60 fueron capaces de realizar maniobras espirométricas aceptables y reproducibles, de acuerdo a los criterios ATS/ERS. El modelo de regresión lineal no transformado que incluía la altura, obtuvo las mejores correlaciones. La introducción de otras variables no mejoraba significativamente los resultados. Los coeficientes de correlación para FVC, FEV 1 and FEV 0,5 fueron 0.89, 0.88 y 0.86 respectivamente. Las ecuaciones de regresión para el cálculo de los valores de referencia fueron: FEVC= -2,6+0,036*altura (cm) FEV 1 = -2.04 + 0.029*altura (cm) FEV 0,5 = -1,53+ 0,022*altura (cm) El cociente FEV 1 /FVC disminuía con la edad y la altura, si bien los resultados de los distintos modelos eran pobres y no permitían el uso de las ecuaciones de regresión para el cálculo de valores de referencia. Obtuvimos valores de FeNO en 56 niños. El valor medio fue 11 ppb (SD 4,9) con un rango entre 5 y 18 ppb. Conclusiones: La mayoría de los preescolares de nuestra área pudieron realizar espirometrías de calidad. Se han obtenido ecuaciones de regresión que nos permiten calcular los rangos de referencia en nuestra población y también la distribución de los valores normales de FeNO (AU)