title: Sequential application of oxygen therapy via high-flow nasal cannula and noninvasive ventilation in acute respiratory failure: an observational pilot study.
abstract: BACKGROUND
  The aim of this study was to evaluate the clinical efficacy of humidified oxygen via high-flow nasal cannula (HFNC) alternating with noninvasive ventilation (NIV) in acute hypoxemic respiratory failure (AHRF).
  
  
  METHODS
  We performed a prospective observational study in a 12-bed ICU of a university hospital. All subjects with a PaO2 /FIO2 of ≤300 mm Hg with standard mask oxygen and a breathing frequency of > 30 breaths/min or signs of respiratory distress were included and treated with HFNC first and then NIV. Ventilatory parameters, blood gases, and tolerance were recorded during 2 consecutive sessions of NIV and HFNC. Outcome was assessed after continuation of this noninvasive strategy.
  
  
  RESULTS
  Twenty-eight subjects with AHRF were studied, including 23 (82%) with ARDS. Compared with standard oxygen therapy, PaO2 significantly increased from 83 (68-97) mm Hg to 108 (83-140) mm Hg using HFNC and to 125 (97-200) mm Hg using NIV (P<.01), whereas breathing frequency significantly decreased. HFNC was significantly better tolerated than NIV, with a lower score on the visual analog scale. The non-intubated subjects received HFNC for 75 (27-127) h and NIV for 23 (8-31) h. Intubation was required in 10 of 28 subjects (36%), including 8 of 23 subjects with ARDS (35%). After HFNC initiation, a breathing frequency of ≥30 breaths/min was an early factor associated with intubation.
  
  
  CONCLUSIONS
  HFNC was better tolerated than NIV and allowed for significant improvement in oxygenation and tachypnea compared with standard oxygen therapy in subjects with AHRF, a large majority of whom had ARDS. Thus, HFNC may be used between NIV sessions to avoid marked impairment of oxygenation.
authors.affiliation: Réanimation Médicale Institut National de la Santé et de la Recherche Médicale, CIC-1402, Université de Poitiers, Poitiers, France. jean-pierre.frat@chu-poitiers.fr.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Frat
authors.affiliation: Réanimation Médicale.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Brugiere
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, CIC-1402, Université de Poitiers, Poitiers, France.
authors.forename: Stéphanie
authors.initials: S
authors.lastname: Ragot
authors.affiliation: Réanimation Médicale.
authors.forename: Delphine
authors.initials: D
authors.lastname: Chatellier
authors.affiliation: Réanimation Médicale.
authors.forename: Anne
authors.initials: A
authors.lastname: Veinstein
authors.affiliation: Réanimation Médicale.
authors.forename: Véronique
authors.initials: V
authors.lastname: Goudet
authors.affiliation: Réanimation Médicale.
authors.forename: Rémi
authors.initials: R
authors.lastname: Coudroy
authors.affiliation: Département d'Anesthésie-Réanimation, Centre Hospitalier Universitaire de Poitiers, Poitiers, France.
authors.forename: Franck
authors.initials: F
authors.lastname: Petitpas
authors.affiliation: Réanimation Médicale Institut National de la Santé et de la Recherche Médicale, CIC-1402, Université de Poitiers, Poitiers, France.
authors.forename: René
authors.initials: R
authors.lastname: Robert
authors.affiliation: Réanimation Médicale Institut National de la Santé et de la Recherche Médicale, CIC-1402, Université de Poitiers, Poitiers, France.
authors.forename: Arnaud W
authors.initials: AW
authors.lastname: Thille
authors.affiliation: Medical Intensive Care Department, Centre Hospitalier Universitaire de Rouen, Charles Nicolle University Hospital, Rouen, France and UPRES EA 3830-IRIB, Rouen University, Rouen, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Girault
mesh_terms: D000208:Acute Disease; D000368:Aged; D057785:Catheters; D005260:Female; D006801:Humans; D000860:Hypoxia / Q000209:etiology / Q000628:therapy*; D007362:Intensive Care Units; D007442:Intubation, Intratracheal; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation; D009666:Nose; D010100:Oxygen / Q000008:administration & dosage / Q000097:blood; D010102:Oxygen Inhalation Therapy / Q000379:methods*; D010313:Partial Pressure; D017060:Patient Satisfaction; D010865:Pilot Projects; D011446:Prospective Studies; D012128:Respiratory Distress Syndrome / Q000150:complications / Q000628:therapy*; D012131:Respiratory Insufficiency / Q000150:complications / Q000628:therapy*; D056152:Respiratory Rate; D012720:Severity of Illness Index; D017211:Treatment Failure
chemical_list: D010100:Oxygen
keywords: acute respiratory distress syndrome (ARDS); acute respiratory failure; intensive care unit (ICU); nasal high-flow oxygen therapy; noninvasive ventilation