title: High-flow nasal cannulae are associated with increased diaphragm activation compared with nasal continuous positive airway pressure in preterm infants.
abstract: OBJECTIVE
  High-flow nasal cannulae (HFNC) are increasingly used for respiratory management of preterm infants. However, their ability to provide support compared to nasal continuous positive airway pressure (CPAP) has been questioned. We compared the effect of HFNC versus nasal CPAP on diaphragm electrical activity (EAdi) in preterm infants.
  
  
  METHODS
  Preterm infants ≤1500 g were randomised in a crossover design to receive 2 hours of either Infant Flow(®) CPAP (IF-CPAP) at 5-6 cmH2 O or HFNC with the flow rate adjusted to achieve an equivalent pharyngeal pressure. A feeding catheter with miniaturised sensors was inserted for continuous EAdi measurement.
  
  
  RESULTS
  The study comprised ten infants. Physiologic parameters and oxygen requirements were not different between the two modes. However, seven infants demonstrated a higher EAdi peak and six showed a higher EAdi tonic on HFNC, even though the mean group data showed no difference between HFNC and IF-CPAP. Neural inspiratory time was significantly longer with HFNC than IF-CPAP (0.55 ± 0.11 versus 0.48 ± 0.06 seconds, p = 0.018).
  
  
  CONCLUSIONS
  In this cohort of preterm infants, the majority exhibited greater diaphragm activation, as assessed by neural breathing patterns, when supported with HFNC than IF-CPAP, suggesting that nasal CPAP may provide more effective respiratory support.
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
authors.forename: Nehad
authors.initials: N
authors.lastname: Nasef
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
authors.forename: Enas
authors.initials: E
authors.lastname: El-Gouhary
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
authors.forename: Patti
authors.initials: P
authors.lastname: Schurr
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.
authors.forename: Maureen
authors.initials: M
authors.lastname: Reilly
authors.affiliation: Keenan Research Centre for Biomedical Science, Department of Critical Care, St. Michael's Hospital, Toronto, ON, Canada.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Beck
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.|Division of Neonatology, Department of Paediatrics, University of Toronto, Toronto, ON, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Dunn
authors.affiliation: Women and Babies Program, Sunnybrook Health Sciences Centre, Toronto, ON, Canada.|Division of Neonatology, Department of Paediatrics, University of Toronto, Toronto, ON, Canada.
authors.forename: Eugene
authors.initials: E
authors.lastname: Ng
mesh_terms: D057785:Catheters; D045422:Continuous Positive Airway Pressure; D018592:Cross-Over Studies; D003964:Diaphragm / Q000502:physiology*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D008297:Male; D009666:Nose; D011446:Prospective Studies; D012121:Respiration, Artificial / Q000295:instrumentation*; D012127:Respiratory Distress Syndrome, Newborn / Q000628:therapy*
keywords: Continuous positive airway pressure; Diaphragm; Electromyography; High-flow nasal cannulae; Infants