Videolaryngoscopy for Intubation in Patients With Diabetes
Condition: Anesthesia; Diabetes Mellitus; Intubation;Difficult; Videolaryngoscopy
MeSH terms: Diabetes Mellitus
Study type: Interventional

Summary: 
      The use of videolarygoscopy (VL) as first choice for tracheal intubation versus direct
      laryngoscopy (DL) is a matter of debate.

      These two methods were compared in several studies. Videolaryngoscopes may reduce the number
      of failed intubations, particularly among patients presenting with a difficult airway. They
      improve the glottic view and may reduce airway trauma. DM is accepted as a risk factor for
      difficult intubation.

      The aim of this study is to compare VL to DL in adult patients requiring tracheal intubation
      for anesthesia, in terms of intubation success, glottic view quality, intubation failure,
      intubation time, conversion to another laringoscopy method and adverse outcomes related to
      tracheal intubation.
    

Detailed description: 
      The use of videolarygoscopy (VL) as first choice for tracheal intubation versus direct
      laryngoscopy (DL) is a matter of debate.

      These two methods were compared in several studies. First attempt intubation success and
      glottic visualization with VL versus DL by pediatric emergency medicine providers in
      simulated patients were evaluated and it was concluded that VL was associated with greater
      first-attempt success during intubation by pediatric emergency physicians on an adult
      simulator.

      The ease of viewing the glottis under direct vision during conventional laryngoscopy with the
      quality of indirectly viewing on a monitor during laryngoscopy with a Macintosh
      videolaryngoscope was compared in a multicenter study. The results were that VL can lead to
      better viewing conditions but in rare cases it may result in worse viewing conditions.

      The study evaluating the efficacy and safety of VL compared to DL in decreasing the time and
      attempts required and increasing the success rate for endotracheal intubation in neonates
      concluded that there was insufficient evidence to recommend or refute the use of VL for
      endotracheal intubation in neonates.

      Diverse videolaryngoscopes where also compared in patients undergoing tracheal intubation for
      elective surgery: the GlideScope Ranger (GlideScope, Bothell, WA), the V-MAC Storz Berci DCI
      (Karl Storz, Tuttlingen, Germany), and the McGrath (McGrath series 5, Aircraft medical,
      Edinburgh, UK) and tested whether it is feasible to intubate the trachea of patients with
      indirect videolaryngoscopy without using a stylet. The authors concluded that the trachea of
      a large proportion of patients with normal airways can be intubated successfully with certain
      VL blades without using a stylet, although the three studied VL's clearly differ in outcome.
      The Storz VL displaces soft tissues in the fashion of a classic Macintosh scope, affording
      room for tracheal tube insertion and limiting the need for stylet use compared with the other
      two scopes. Although VL's offer several advantages, including better visualization of the
      glottic entrance and intubation conditions, a good laryngeal view does not guarantee easy or
      successful tracheal tube insertion.

      Three different videolarygoscope devices were compared to direct laringoscopy in obese
      patients undergoing bariatric surgery: Video Mac and GlideScope required fewer intubation
      attempts that DL and Video Mac provide shorter intubation times and improved glottis view
      compared to DL.

      A recent metanalysis stated that videolaryngoscopes may reduce the number of failed
      intubations, particularly among patients presenting with a difficult airway. They improve the
      glottic view and may reduce laryngeal/airway trauma. However currently, no evidence indicates
      that use of a VLS reduces the number of intubation attempts or the incidence of hypoxia or
      respiratory complications, and no evidence indicates that use of a VL's affects time required
      for intubation.

      DM is accepted as a risk factor for difficult intubation. The aim of this study is to compare
      VL to DL in adult diabetic patients requiring tracheal intubation for anesthesia, in terms of
      intubation success, glottic view quality, intubation failure, intubation time, conversion to
      another laringoscopy method and adverse outcomes related to tracheal intubation.

      METHODS After obtaining ethical approval and written informed patient consent, consecutive
      patients having diabetes mellitus (DM) and requiring elective intubation for anesthesia will
      be randomly allocated to either the videolaryngoscopy (McGRATH MAC videolaryngoscope) (Group
      VL) or the direct larngoscopy (Macintosh laryngoscope) (Group DL). Age, gender, body mass
      index, American Society of Anesthesiologists (ASA) physiologic classification, the duration
      of DM will be recorded. The patients will be evaluated for difficult airway predictors and
      the following parameters will be recorded: Malampati class, thyromental distance,
      sternomental distance, mandibulohyoid distance, interincisor distance, neck circumference,
      the ability of upper lip overbite and lower lip overbite, the presence of limited neck
      extension. Fentanyl-propofol-rocuronium will be used for anesthesia induction. After
      subsequent positive-pressure ventilation using a face mask and an oxygen-air-sevoflurane
      mixture for 3 min, the trachea will be intubated according to group allocation using either
      DL or VL. During intubation, the following data will be documented: intubation time, number
      of intubation attempts, use of extra tools to facilitate intubation, conversion to another
      laryngoscopy method,intubation difficulty score and the quality of the view of the glottis
      will be assessed according to the Cormack and Lehane scoring system and the percentage of
      glottic opening. Adverse events related to tracheal intubation will be also evaluated:
      desaturation (SPO2<94), hypercabia (ETCO2>35), hypertension (mean arterial pressure >20%
      above baseline values), tachycardia (heart rate >20% above baseline values), new onset
      arrhythmia, laryngospasm, bronchospasm, airway trauma and sore throat in PACU).

      The primary outcome measure is the first-attempt intubation success; intubation timeand ease
      of intubation, secondary outcome measures are the glottic view guality, conversion to another
      laryngoscopy method and adverse outcomes related to tracheal intubation.
    

Intervention name(s): Videolaryngoscopy; laringoscope
Intervention type(s): Device; Device
Intervention description(s): the trachea will be intubated with a videolaryngoscope; the trachea will be intubated with a laringoscope
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: Prosspective randomised
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: Direct laryngoscopy; Videolaryngoscopy; Diabetes Mellitus; Intubation; Anesthesia