A prospective observational pilot study for the assessment of inter-rater agreement/ reliability of the Fremantle and VCI scores in cancer patients undergoing videolaryngoscopic orotracheal intubations at a tertiary care oncological centre

The Glottic Visualisation is an important aspect of determining the difficulty in intubation in a direct laryngoscopy, as the direct line of sight corresponds to the direction of the tube during intubation. This was the principle in establishing the Cormack and Lehane Grading system and further modifications of it [1,2]-To give the subsequent airway operator an idea about the means and method of airway handling to be used. Hence an accurate and reproducible recording of laryngoscopic view at tracheal intubation is an important aspect of anaesthetic practice.

For Videolaryngoscopy a similar system was established by Levitan et al, The Percentage of Glottic Opening (POGO) score [3,11]. Unlike direct laryngoscopy, in which the view achieved by the line of sight directly relates to the ease of intubating the trachea, videolaryngoscopy can create a situation in which the view is good, but intubation is difficult or impossible as it offers an indirect view of the Glottis. A good or complete glottis view on Videolaryngoscopy does not essentially translate into an easy and successful intubation with a Videolaryngoscope [4,8].Videolaryngoscopy does not achieve a 100% intubation success rate, and complications have been associated with the procedure [5,6,7]. With videolaryngoscopy, the success of intubation lies not in the view obtained, but in the ease of inserting the endotracheal tube.

This has created the need for a different scoring system other than the standard Cormack Lehane Grading for direct laryngoscopic intubations or Levitan et al’s Percentage of Glottic Opening (POGO) Score. Any scoring system based solely on view does not adequately describe the issue encountered at videolaryngoscopy of a good view of the glottis but difficulty in intubation. The Fremantle and VCI scoring systems for Videolaryngoscopic intubation addresses these pitfalls.

The key to a successful outcome lies not in the view obtained but in the ease of inserting the endotracheal tube and this must be taken into account in any scoring system. If videolaryngoscopy is planned and a device has been previously documented to easily facilitate intubation at the first attempt then view obtained on the video screen is only a small part of the information that an anaesthetist wants to know. The Fremantle Score/VCI score is an attempt to improve the description of intubation by video laryngoscopes [9,10].