RT Journal Article SR Electronic T1 Electrical activity of the diaphragm during nCPAP and high flow nasal cannula JF Archives of Disease in Childhood - Fetal and Neonatal Edition JO Arch Dis Child Fetal Neonatal Ed FD BMJ Publishing Group Ltd and Royal College of Paediatrics and Child Health SP fetalneonatal-2016-312300 DO 10.1136/archdischild-2016-312300 A1 C G de Waal A1 G J Hutten A1 J V Kraaijenga A1 F H de Jongh A1 A H van Kaam YR 2017 UL http://fn.bmj.com/content/early/2017/03/14/archdischild-2016-312300.abstract AB Objective To determine if the electrical activity of the diaphragm, as measure of neural respiratory drive and breathing effort, changes over time in preterm infants transitioned from nasal continuous positive airway pressure (nCPAP) to high flow nasal cannula (HFNC).Design Prospective observational study.Setting Neonatal intensive care unit.Patients Stable preterm infants transitioned from nCPAP to HFNC using a 1:1 pressure to flow ratio.Interventions The electrical activity of the diaphragm was measured by transcutaneous electromyography (dEMG) from 30 min before until 3 hours after the transition.Main outcome measures At eight time points after the transition to HFNC, diaphragmatic activity was compared with the baseline on nCPAP. Percentage change in amplitudedEMG, peakdEMG and tonicdEMG were calculated. Furthermore, changes in respiratory rate, heart rate and fraction of inspired oxygen (FiO2) were analysed.Results Thirty-two preterm infants (mean gestational age: 28.1±2.2 weeks, mean birth weight: 1118±368 g) were included. Compared with nCPAP, the electrical activity of the diaphragm did not change during the first 3 hours on HFNC (median (IQR) change in amplitudedEMG at t=180 min: 2.81% (−21.51–14.10)). The respiratory rate, heart rate and FiO2 remained stable during the 3-hour measurement.Conclusions Neural respiratory drive and breathing effort assessed by electrical activity of the diaphragm is similar in the first 3 hours after transitioning stable preterm infants from nCPAP to HFNC with a 1:1 pressure-to-flow ratio.