F M Ducharme1, G M Davis, G R Ducharme. 1. Department of Pediatrics, Montreal Children's Hospital, McGill University Faculty of Medicine, Quebec, Canada.
Abstract
OBJECTIVES: To determine, in North American children, reference values for respiratory resistance measurements by the forced oscillation (Rfo) technique and to examine whether sitting height, as index of truncal length, is a better determinant of resistance, less influenced by race and gender, than standing height. DESIGN/ SETTING: A prospective cross-sectional study of healthy nonobese children, carefully selected for absence of atopy, exposure to tobacco smoke, and recent upper respiratory tract infection. MEASUREMENTS: Three measurements of respiratory resistance by forced oscillation were obtained at the fixed frequencies of 8 Hz (Rfo8), 12 Hz (Rfo12), and at 16 Hz (Rfo16) using the Custo Vit R (Custo Med GMBH; Munich, Germany). In cooperative children, routine spirometry (FEV1, FVC, and peak expiratory flow rate [PEFR]) was also performed. RESULTS: We recruited 217 healthy children aged 3 to 17 years. Reproducible measurements of Rfo8 were obtained for 206 children, Rfo12 for 197 children, and Rfo16 for 209 children. Normal FEV1, FVC, and PEFR values were documented in all 69 subjects who were able to reproducibly cooperate with spirometry. Multiple linear regression identified measurements of either sitting or standing height as the best, and equally strong, determinants of respiratory resistance at all three frequencies. Gender and race were not important factors once either sitting or standing height measurement was considered. Our regression equations at 8 Hz are comparable to published reference values obtained at fixed frequencies of 6, 8, and 10 Hz using other instruments. However, in comparison to our results, prior values tended to underestimate resistance in the shortest children or to overestimate it in the tallest ones. Our regression equation for Rfo12 is similar to the only previously published one, while no reference values at 16 Hz were available for comparison. CONCLUSIONS: Height is the best predictor for total respiratory resistance at 8, 12, and 16 Hz in children aged > or = 3 years. Use of sitting height does not appear to be a stronger determinant of resistance than standing height.
OBJECTIVES: To determine, in North American children, reference values for respiratory resistance measurements by the forced oscillation (Rfo) technique and to examine whether sitting height, as index of truncal length, is a better determinant of resistance, less influenced by race and gender, than standing height. DESIGN/ SETTING: A prospective cross-sectional study of healthy nonobese children, carefully selected for absence of atopy, exposure to tobacco smoke, and recent upper respiratory tract infection. MEASUREMENTS: Three measurements of respiratory resistance by forced oscillation were obtained at the fixed frequencies of 8 Hz (Rfo8), 12 Hz (Rfo12), and at 16 Hz (Rfo16) using the Custo Vit R (Custo Med GMBH; Munich, Germany). In cooperative children, routine spirometry (FEV1, FVC, and peak expiratory flow rate [PEFR]) was also performed. RESULTS: We recruited 217 healthy children aged 3 to 17 years. Reproducible measurements of Rfo8 were obtained for 206 children, Rfo12 for 197 children, and Rfo16 for 209 children. Normal FEV1, FVC, and PEFR values were documented in all 69 subjects who were able to reproducibly cooperate with spirometry. Multiple linear regression identified measurements of either sitting or standing height as the best, and equally strong, determinants of respiratory resistance at all three frequencies. Gender and race were not important factors once either sitting or standing height measurement was considered. Our regression equations at 8 Hz are comparable to published reference values obtained at fixed frequencies of 6, 8, and 10 Hz using other instruments. However, in comparison to our results, prior values tended to underestimate resistance in the shortest children or to overestimate it in the tallest ones. Our regression equation for Rfo12 is similar to the only previously published one, while no reference values at 16 Hz were available for comparison. CONCLUSIONS: Height is the best predictor for total respiratory resistance at 8, 12, and 16 Hz in children aged > or = 3 years. Use of sitting height does not appear to be a stronger determinant of resistance than standing height.
Authors: Graham L Hall; Peter D Sly; Takayoshi Fukushima; Merci M Kusel; Peter J Franklin; Friedrich Horak; Hilary Patterson; Catherine Gangell; Stephen M Stick Journal: Thorax Date: 2007-01-24 Impact factor: 9.139
Authors: Alice Trye; Kenneth I Berger; Mrudula Naidu; Teresa M Attina; Joseph Gilbert; Tony T Koshy; Xiaoxia Han; Michael Marmor; Yongzhao Shao; Robert Giusti; Roberta M Goldring; Leonardo Trasande Journal: J Pediatr Date: 2018-07-18 Impact factor: 4.406
Authors: Jye Hae Park; Jung Won Yoon; Youn Ho Shin; Hye Mi Jee; Young Sun Wee; Sun Jung Chang; Jung Hwa Sim; Hye Yung Yum; Man Yong Han Journal: Korean J Pediatr Date: 2011-02-28
Authors: F M Ducharme; R Zemek; J Gravel; D Chalut; N Poonai; S Laberge; C Quach; M Krajinovic; C Guimont; C Lemière; M C Guertin Journal: BMJ Open Date: 2014-04-07 Impact factor: 2.692