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ADC-FNN Online First, published on March 13, 2014 as 10.1136/archdischild-2013-305033 Original article
Are high flow nasal cannulae noisier than bubble CPAP for preterm infants? C T Roberts,1 J A Dawson,1,2,3 E Alquoka,4 P J Carew,4 S M Donath,5,6 P G Davis,1,2,3 B J Manley1,2,3 ▸ Additional material is published online only. To view please visit the journal online (http://dx.doi.org/10.1136/ archdischild-2013-305033). 1
Newborn Research Centre, The Royal Women’s Hospital, Melbourne, Australia 2 Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia 3 Critical Care and Neurosciences, Murdoch Children’s Research Institute, Melbourne, Australia 4 Department of Audiology and Speech Pathology, The University of Melbourne, Melbourne, Australia 5 Clinical Epidemiology and Biostatistics Unit, Murdoch Children’s Research Institute, Melbourne, Australia 6 Department of Paediatrics, The University of Melbourne, Melbourne, Australia Correspondence to Dr Calum T Roberts, Newborn Research Centre, The Royal Women’s Hospital, Level 7, 20 Flemington Road, Parkville, Vic 3052, Australia; calum. [email protected] Received 13 August 2013 Revised 17 February 2014 Accepted 20 February 2014
ABSTRACT Background Noise exposure in the neonatal intensive care unit is believed to be a risk factor for hearing loss in preterm neonates. Continuous positive airway pressure (CPAP) devices exceed recommended noise levels. High flow nasal cannulae (HFNC) are an increasingly popular alternative to CPAP for treating preterm infants, but there are no in vivo studies assessing noise production by HFNC. Objective To study whether HFNC are noisier than bubble CPAP (BCPAP) for preterm infants. Methods An observational study of preterm infants receiving HFNC or BCPAP. Noise levels within the external auditory meatus (EAM) were measured using a microphone probe tube connected to a calibrated digital dosimeter. Noise was measured across a range of frequencies and reported as decibels A-weighted (dBA). Results A total of 21 HFNC and 13 BCPAP noise measurements were performed in 21 infants. HFNC gas flows were 2–5 L/min, and BCPAP gas flows were 6–10 L/min with set pressures of 5–7 cm of water. There was no evidence of a difference in average noise levels measured at the EAM: mean difference (95% CI) of −1.6 (−4.0 to 0.9) dBA for HFNC compared to BCPAP. At low frequency (500 Hz), HFNC was mean (95% CI) 3.0 (0.3 to 5.7) dBA quieter than BCPAP. Noise increased with increasing BCPAP gas flow ( p=0.007), but not with increasing set pressure. There was a trend to noise increasing with increasing HFNC gas flows. Conclusions At the gas flows studied, HFNC are not noisier than BCPAP for preterm infants.
BACKGROUND
To cite: Roberts CT, Dawson JA, Alquoka E, et al. Arch Dis Child Fetal Neonatal Ed Published Online First: [ please include Day Month Year] doi:10.1136/archdischild2013-305033
Permanent hearing loss is a recognised complication of being born extremely preterm. In a population-based study of children born ≤28 weeks’ gestation or
ADC-FNN Online First, published on March 13, 2014 as 10.1136/archdischild-2013-305033 Original article
Are high flow nasal cannulae noisier than bubble CPAP for preterm infants? C T Roberts,1 J A Dawson,1,2,3 E Alquoka,4 P J Carew,4 S M Donath,5,6 P G Davis,1,2,3 B J Manley1,2,3 ▸ Additional material is published online only. To view please visit the journal online (http://dx.doi.org/10.1136/ archdischild-2013-305033). 1
Newborn Research Centre, The Royal Women’s Hospital, Melbourne, Australia 2 Department of Obstetrics and Gynaecology, The University of Melbourne, Melbourne, Australia 3 Critical Care and Neurosciences, Murdoch Children’s Research Institute, Melbourne, Australia 4 Department of Audiology and Speech Pathology, The University of Melbourne, Melbourne, Australia 5 Clinical Epidemiology and Biostatistics Unit, Murdoch Children’s Research Institute, Melbourne, Australia 6 Department of Paediatrics, The University of Melbourne, Melbourne, Australia Correspondence to Dr Calum T Roberts, Newborn Research Centre, The Royal Women’s Hospital, Level 7, 20 Flemington Road, Parkville, Vic 3052, Australia; calum. [email protected] Received 13 August 2013 Revised 17 February 2014 Accepted 20 February 2014
ABSTRACT Background Noise exposure in the neonatal intensive care unit is believed to be a risk factor for hearing loss in preterm neonates. Continuous positive airway pressure (CPAP) devices exceed recommended noise levels. High flow nasal cannulae (HFNC) are an increasingly popular alternative to CPAP for treating preterm infants, but there are no in vivo studies assessing noise production by HFNC. Objective To study whether HFNC are noisier than bubble CPAP (BCPAP) for preterm infants. Methods An observational study of preterm infants receiving HFNC or BCPAP. Noise levels within the external auditory meatus (EAM) were measured using a microphone probe tube connected to a calibrated digital dosimeter. Noise was measured across a range of frequencies and reported as decibels A-weighted (dBA). Results A total of 21 HFNC and 13 BCPAP noise measurements were performed in 21 infants. HFNC gas flows were 2–5 L/min, and BCPAP gas flows were 6–10 L/min with set pressures of 5–7 cm of water. There was no evidence of a difference in average noise levels measured at the EAM: mean difference (95% CI) of −1.6 (−4.0 to 0.9) dBA for HFNC compared to BCPAP. At low frequency (500 Hz), HFNC was mean (95% CI) 3.0 (0.3 to 5.7) dBA quieter than BCPAP. Noise increased with increasing BCPAP gas flow ( p=0.007), but not with increasing set pressure. There was a trend to noise increasing with increasing HFNC gas flows. Conclusions At the gas flows studied, HFNC are not noisier than BCPAP for preterm infants.
BACKGROUND
To cite: Roberts CT, Dawson JA, Alquoka E, et al. Arch Dis Child Fetal Neonatal Ed Published Online First: [ please include Day Month Year] doi:10.1136/archdischild2013-305033
Permanent hearing loss is a recognised complication of being born extremely preterm. In a population-based study of children born ≤28 weeks’ gestation or
