title: Comparison of intubation success and glottic visualization using King Vision and C-MAC videolaryngoscopes in patients with cervical spine injuries with cervical immobilization: A randomized clinical trial.
abstract: BACKGROUND
  Glottic visualization can be difficult with cervical immobilization in patients with cervical spine injury. Indirect laryngoscopes may provide better glottic visualization in these groups of patients. Hence, we compared King Vision videolaryngoscope, C-MAC videolaryngoscope for endotracheal intubation in patients with proven/suspected cervical spine injury.
  
  
  METHODS
  After standard induction of anesthesia, 135 patients were randomized into three groups: group C (conventional C-MAC videolaryngoscope), group K (King Vision videolaryngoscope), and group D (D blade C-MAC videolaryngoscope). Cervical immobilization was maintained with Manual in line stabilization with anterior part of cervical collar removed. First pass intubation success, time for intubation, and glottic visualization (Cormack - Lehane grade and percentage of glottic opening) were noted. Intubation difficulty score (IDS) was used for grading difficulty of intubation. Five-point Likert scale was used for ease of insertion of laryngoscope.
  
  
  RESULTS
  First attempt success rate were 100% (45/45), 93.3% (42/45), and 95.6% (43/45) in patients using conventional C-MAC, King Vision, and D blade C-MAC videolaryngoscopes, respectively. Time for intubation in seconds was significantly faster with conventional C-MAC videolaryngoscope (23.3 ± 4.7) compared to D blade C-MAC videolaryngoscope (26.7 ± 7.1), whereas conventional C-MAC and King Vision were comparable (24.9 ± 7.2). Good grade glottic visualization was obtained with all the three videolaryngoscopes.
  
  
  CONCLUSIONS
  All the videolaryngoscopes provided good glottic visualization and first attempt success rate. Conventional C-MAC insertion was significantly easier. We conclude that all the three videolaryngoscopes can be used effectively in patients with cervical spine injury.
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: Dhanyasi
authors.initials: D
authors.lastname: Shravanalakshmi
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: Prasanna U
authors.initials: PU
authors.lastname: Bidkar
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: K
authors.initials: K
authors.lastname: Narmadalakshmi
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: Suman
authors.initials: S
authors.lastname: Lata
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: Sandeep K
authors.initials: SK
authors.lastname: Mishra
authors.affiliation: Department of Anaesthesiology and Critical Care, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, India.
authors.forename: S
authors.initials: S
authors.lastname: Adinarayanan
keywords: Cervical spine immobilization; glottic visualization; videolaryngoscopes