title: Head elevation improves laryngeal exposure with direct laryngoscopy.
abstract: OBJECTIVE
  The aim of this study was to examine the effect of changing head position on the laryngeal view in the same subject.
  
  
  METHODS
  Prospective, randomized, crossover comparison of laryngeal views.
  
  
  METHODS
  Operating suite at a university-affiliated, community hospital.
  
  
  METHODS
  One hundred sixty-seven consenting adult patients scheduled to undergo elective surgery with general anesthesia.
  
  
  METHODS
  After anesthesia induction and muscle relaxation and the head in extended position, the laryngeal view was graded in 3 different head height positions. A special inflatable pillow was placed under the subject's head before induction and was deflated to produce no head elevation or inflated to produce either 6.0cm (sniffing position), or 10.0cm elevation (elevated sniffing position) in random order.
  
  
  RESULTS
  The incidence of difficult laryngoscopy (grade ≥3) was 8.38% with no head elevation, 2.39% in the sniffing position, and 1.19% in the elevated sniffing position. Head elevation was not associated with a worse grade in any single patient.
  
  
  CONCLUSIONS
  Sniffing position improves glottic exposure when the laryngoscopic grade is greater than 1 in the head-flat position. The elevated sniffing position improves the view to a better grade in some patients. Because head elevation was not associated with a worse grade in any subject, the elevated sniffing position should be considered as the initial head position before direct laryngoscopy when a difficult exposure is anticipated.
authors.affiliation: Medical College of Wisconsin, Milwaukee, Wis,. Electronic address: elorbany@mcw.edu.
authors.forename: Mohammad I
authors.initials: MI
authors.lastname: El-Orbany
authors.affiliation: Geisinger Medical Center, Danville Pa; Clinical Associate Professor of Anesthesiology, Temple University, Philadelphia, Pa.
authors.forename: Yohannes B
authors.initials: YB
authors.lastname: Getachew
authors.affiliation: Chicago ENT, Chicago, Ill.
authors.forename: Ninos J
authors.initials: NJ
authors.lastname: Joseph
authors.affiliation: Advocate Illinois Masonic Medical Center, Chicago, Ill; Clinical Professor of Anesthesiology, University of Illinois, Chicago, Ill.
authors.forename: M Ramez
authors.initials: MR
authors.lastname: Salem
authors.affiliation: Section of Head and Neck Surgery, Department of Otolaryngology, Advocate Illinois Masonic Medical Center, Chicago, Ill; Professor of Otolaryngology, Rush University, Chicago, Ill.
authors.forename: Michael
authors.initials: M
authors.lastname: Friedman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000768:Anesthesia, General / Q000379:methods; D018592:Cross-Over Studies; D005260:Female; D006257:Head / Q000033:anatomy & histology; D019416:Head Movements; D006801:Humans; D007442:Intubation, Intratracheal / Q000379:methods; D007828:Laryngoscopy / Q000379:methods*; D007830:Larynx / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning / Q000379:methods*; D011187:Posture / Q000502:physiology; D011446:Prospective Studies; D055815:Young Adult
keywords: Direct laryngoscopy; Sniffing position