title: Influence of nose and mouth leaks on peripheral oxygen saturation during continuous positive airway pressure in neonates.
abstract: BACKGROUND
  Nose and mouth leaks impair effective pressure transmission during neonatal continuous positive airway pressure (CPAP), but little is known about how these leaks affect physiological parameters. This study investigated the influence of nose leaks and spontaneous mouth opening on peripheral oxygen saturation (SpO₂) and respiratory rate (RR) using nasopharyngeal CPAP.
  
  
  METHODS
  In 32 neonates with a gestational age of 30 (24-38) weeks and a birth weight of 1435 (710-2730) g, SpO₂ and RR measurements were taken with and without occlusion of the contralateral nostril in a randomized cross-over trial in 1-minute intervals over a 10-minute period during each condition. Mouth opening and newborn activity were documented.
  
  
  RESULTS
  SpO₂ with open nostril was comparable to that with occluded nostril [93 (78.5-99.5)% vs. 94 (80-100)%, P=0.20]. RR decreased from 51 (26-82)/min to 48 (32-85)/min (P=0.027). In infants with an SpO₂ ≤ 93% during open nostril (n=17), SpO₂ increased after nostril occlusion [91 (80-96)% vs. 89.5 (78.5-93)%, P=0.036]. The mouth was open in 78.5% of measurements with open nostril, and in 87.4% of measurements after nostril occlusion (P=0.005). No significant influence of mouth opening or closure on SpO₂ or RR was detected.
  
  
  CONCLUSIONS
  In neonates on unilateral nasopharyngeal CPAP with an SpO₂ ≤ 93%, occlusion of the contralateral nostril significantly increased SpO₂ and reduced RR. The beneficial physiological effects further support using binasal prongs to minimize nose leaks in this population. Future studies should investigate the beneficial effects of reducing mouth leaks when applying CPAP to these infants.
authors.affiliation: Department of Neonatology, Charité University Medicine Berlin, Berlin, Germany, hendrik.fischer@charite.de.
authors.forename: Hendrik Stefan
authors.initials: HS
authors.lastname: Fischer
authors.forename: Charles Christoph
authors.initials: CC
authors.lastname: Roehr
authors.forename: Hans
authors.initials: H
authors.lastname: Proquitté
authors.forename: Gerd
authors.initials: G
authors.lastname: Schmalisch
mesh_terms: D045422:Continuous Positive Airway Pressure / Q000379:methods; D018592:Cross-Over Studies; D006801:Humans; D007231:Infant, Newborn; D009055:Mouth; D015508:Nasal Obstruction; D009305:Nasopharynx; D010100:Oxygen / Q000097:blood*; D011446:Prospective Studies; D056152:Respiratory Rate
chemical_list: D010100:Oxygen