title: [Post analysis simulated correlation of the El-Ganzouri airway difficulty score with difficult airway].
abstract: BACKGROUND
  Difficult airway (DA) occurs frequently (5-15%) in clinical practice. The El-Ganzouri Risk Index (EGRI) has a high sensitivity for predicting a difficult intubation (DI). However difficult mask ventilation (DMV) was never included in the EGRI. Since DMV was not included in the EGRI assessment, and obstructive sleep apnea (OSA) is also correlated with DMV, a study correlating the prediction of DA and OSA (identified by STOP-Bang questionnaire, SB) seemed important.
  
  
  METHODS
  We accessed a database previously collected for a post analysis simulation of the airway difficulty predictivity of the EGRI, associated with normal and difficult airway, particularly DMV. As secondary aim, we measured the correlation between the SB prediction system and DA, compared to the EGRI.
  
  
  RESULTS
  A total of 2747 patients were included in the study. The proportion of patients with DI was 14.7% (95% CI 13.4-16) and the proportion of patients with DMV was 3.42% (95% CI 2.7-4.1). The incidence of DMV combined with DI was (2.3%). The optimal cutoff value of EGRI was 3. EGRI registered also an higher ability to predict DMV (AUC=0.76 (95% CI 0.71-0.81)). Adding the SB variables in the logistic model, the AUC increases with the inclusion of "observed apnea" variable (0.83 vs. 0.81, p=0.03). The area under the ROC curve for the patients with DI and DMV was 0.77 (95% CI 0.72-0.83).
  
  
  CONCLUSIONS
  This study confirms that the incidence of DA is not negligible and suggests the use of the EGRI as simple bedside predictive score to improve patient safety.
authors.affiliation: Setor de Emergência, Anestesia e Tratamento Intensivo, G.B. Morgagni-Pierantoni Hospital, Forlì, Itália. Electronic address: rmcorso@gmail.com.
authors.forename: Ruggero M
authors.initials: RM
authors.lastname: Corso
authors.affiliation: Departamento de Anestesiologia, The University of Texas Medical School at Houston, Houston, EUA.
authors.forename: Davide
authors.initials: D
authors.lastname: Cattano
authors.affiliation: Setor de Emergência, Anestesia e Tratamento Intensivo, G.B. Morgagni-Pierantoni Hospital, Forlì, Itália.
authors.forename: Matteo
authors.initials: M
authors.lastname: Buccioli
authors.affiliation: Departamento de Bioestatística e Ensaios Clínicos, Institute Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST), Meldola, Itália.
authors.forename: Elisa
authors.initials: E
authors.lastname: Carretta
authors.affiliation: Setor de Emergência, Anestesia e Tratamento Intensivo, G.B. Morgagni-Pierantoni Hospital, Forlì, Itália.
authors.forename: Stefano
authors.initials: S
authors.lastname: Maitan
keywords: Apneia do sono; Difficult airway; Escore preditivo; Predictive score; Sleep apnea; Via aérea difícil