Karen Eline Stensby Bains1,2,3, Martin Färdig4,5,3, Hrefna Katrín Gudmundsdóttir1,2, Catarina Almqvist5,6, Gunilla Hedlin4,5, Live S Nordhagen7, Eva M Rehbinder2,8, Håvard O Skjerven1,2, Cilla Söderhäll4,5, Riyas Vettukattil1,2, Björn Nordlund4,5, Karin C Lødrup Carlsen1,2. 1. Division of Paediatric and Adolescent Medicine, Oslo University Hospital, Oslo, Norway. 2. University of Oslo, Faculty of Medicine, Institute of Clinical Medicine, Oslo, Norway. 3. These authors contributed equally and share first authorship. 4. Dept of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. 5. Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden. 6. Dept of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden. 7. VID Specialized University, Oslo, Norway. 8. Dept of Dermatology, Oslo University Hospital, Oslo, Norway.
Abstract
Background: Infant lung function can be assessed with tidal flow-volume (TFV) loops. While TFV loops can be measured in both awake and sleeping infants, the influence of arousal state in early infancy is not established. The aim of the present study was to determine whether TFV loop parameters in healthy infants differed while awake compared to the sleeping state at 3 months of age. Methods: From the population-based Scandinavian Preventing Atopic Dermatitis and ALLergies in children (PreventADALL) birth cohort, 91 infants had reproducible TFV loops measured with Exhalyzer® D in both the awake and sleeping state at 3 months of age. The TFV loops were manually selected according to a standardised procedure. The ratio of time to peak tidal expiratory flow (t PTEF) to expiratory time (t E) and the corresponding volume ratio (V PTEF/V E), as well as tidal volume (V T) and respiratory rate were compared using nonparametric tests. Results: The mean (95% CI) t PTEF/t E was significantly higher while awake compared to the sleeping state: 0.39 (0.37-0.41) versus 0.28 (0.27-0.29); with the corresponding V PTEF/V E of 0.38 (0.36-0.40) versus 0.29 (0.28-0.30). The V T was similar, while the respiratory rate was higher while awake compared to the sleeping state: 53 (51-56) breaths·min-1 versus 38 (36-40) breaths·min-1. Conclusion: Higher t PTEF/t E, V PTEF/V E and respiratory rate, but similar V T while awake compared to the sleeping state suggests that separate normative TFV loop values according to arousal state may be required in early infancy.
Background: Infant lung function can be assessed with tidal flow-volume (TFV) loops. While TFV loops can be measured in both awake and sleeping infants, the influence of arousal state in early infancy is not established. The aim of the present study was to determine whether TFV loop parameters in healthy infants differed while awake compared to the sleeping state at 3 months of age. Methods: From the population-based Scandinavian Preventing Atopic Dermatitis and ALLergies in children (PreventADALL) birth cohort, 91 infants had reproducible TFV loops measured with Exhalyzer® D in both the awake and sleeping state at 3 months of age. The TFV loops were manually selected according to a standardised procedure. The ratio of time to peak tidal expiratory flow (t PTEF) to expiratory time (t E) and the corresponding volume ratio (V PTEF/V E), as well as tidal volume (V T) and respiratory rate were compared using nonparametric tests. Results: The mean (95% CI) t PTEF/t E was significantly higher while awake compared to the sleeping state: 0.39 (0.37-0.41) versus 0.28 (0.27-0.29); with the corresponding V PTEF/V E of 0.38 (0.36-0.40) versus 0.29 (0.28-0.30). The V T was similar, while the respiratory rate was higher while awake compared to the sleeping state: 53 (51-56) breaths·min-1 versus 38 (36-40) breaths·min-1. Conclusion: Higher t PTEF/t E, V PTEF/V E and respiratory rate, but similar V T while awake compared to the sleeping state suggests that separate normative TFV loop values according to arousal state may be required in early infancy.
Authors: Nicole Beydon; Stephanie D Davis; Enrico Lombardi; Julian L Allen; Hubertus G M Arets; Paul Aurora; Hans Bisgaard; G Michael Davis; Francine M Ducharme; Howard Eigen; Monika Gappa; Claude Gaultier; Per M Gustafsson; Graham L Hall; Zoltán Hantos; Michael J R Healy; Marcus H Jones; Bent Klug; Karin C Lødrup Carlsen; Sheila A McKenzie; Francçois Marchal; Oscar H Mayer; Peter J F M Merkus; Mohy G Morris; Ellie Oostveen; J Jane Pillow; Paul C Seddon; Michael Silverman; Peter D Sly; Janet Stocks; Robert S Tepper; Daphna Vilozni; Nicola M Wilson Journal: Am J Respir Crit Care Med Date: 2007-06-15 Impact factor: 21.405
Authors: Alexander Moeller; Kai-Hakon Carlsen; Peter D Sly; Eugenio Baraldi; Giorgio Piacentini; Ian Pavord; Christiane Lex; Sejal Saglani Journal: Eur Respir Rev Date: 2015-06