title: Nasal flaring as a clinical sign of respiratory acidosis in patients with dyspnea.
abstract: OBJECTIVE
  To determine whether the presence of nasal flaring is a clinical sign of respiratory acidosis in patients attending emergency departments for acute dyspnea.
  
  
  METHODS
  Single-center, prospective, observational study of patients aged over 15 requiring urgent attention for dyspnea, classified as level II or III according to the Andorran Triage Program and who underwent arterial blood gas test on arrival at the emergency department. The presence of nasal flaring was evaluated by two observers. Demographic and clinical variables, signs of respiratory difficulty, vital signs, arterial blood gases and clinical outcome (hospitalization and mortality) were recorded. Bivariate and multivariate analyses were performed using logistic regression models.
  
  
  RESULTS
  The sample comprised 212 patients, mean age 78years (SD=12.8), of whom 49.5% were women. Acidosis was recorded in 21.2%. Factors significantly associated with the presence of acidosis in the bivariate analysis were the need for pre-hospital medical care, triage level II, signs of respiratory distress, presence of nasal flaring, poor oxygenation, hypercapnia, low bicarbonates and greater need for noninvasive ventilation. Nasal flaring had a positive likelihood ratio for acidosis of 4.6 (95% CI 2.9-7.4). In the multivariate analysis, triage level II (aOR 5.16; 95% CI: 1.91 to 13.98), the need for oxygen therapy (aOR 2.60; 95% CI: 1.13-5.96) and presence of nasal flaring (aOR 6.32; 95% CI: 2.78-14.41) were maintained as factors independently associated with acidosis.
  
  
  CONCLUSIONS
  Nasal flaring is a clinical sign of severity in patients requiring urgent care for acute dyspnea, which has a strong association with acidosis and hypercapnia.
authors.affiliation: Emergency Service, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Barcelona, Spain; Universitat Internacional de Catalunya (UIC), Sant Cugat del Vallès, Barcelona, Spain. Electronic address: jzorrilla@althaia.cat.
authors.forename: José Gregorio
authors.initials: JG
authors.lastname: Zorrilla-Riveiro
authors.affiliation: Research and Innovation Unit, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Arnau-Bartés
authors.affiliation: Emergency Service, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Barcelona, Spain.
authors.forename: Ramón
authors.initials: R
authors.lastname: Rafat-Sellarés
authors.affiliation: Emergency Service, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Barcelona, Spain.
authors.forename: Dolors
authors.initials: D
authors.lastname: García-Pérez
authors.affiliation: Intensive Care Unit, Hospital Sant Joan Despi Moisés Broggi, Barcelona, Barcelona, Spain.
authors.forename: Arantxa
authors.initials: A
authors.lastname: Mas-Serra
authors.affiliation: Universitat Internacional de Catalunya (UIC), Sant Cugat del Vallès, Barcelona, Spain; Intensive Care Unit, Althaia Xarxa Assistencial Universitària de Manresa, Manresa, Barcelona, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Fernández-Fernández
mesh_terms: D000142:Acidosis, Respiratory / Q000097:blood / Q000503:physiopathology* / Q000628:therapy; D000368:Aged; D000369:Aged, 80 and over; D001784:Blood Gas Analysis; D016022:Case-Control Studies; D004417:Dyspnea / Q000097:blood / Q000503:physiopathology* / Q000628:therapy; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000097:blood / Q000503:physiopathology* / Q000628:therapy; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D063087:Noninvasive Ventilation; D009666:Nose; D010102:Oxygen Inhalation Therapy; D010808:Physical Examination; D011446:Prospective Studies; D012720:Severity of Illness Index; D014218:Triage
keywords: Dyspnea; Hypoventilation; Nasal flaring