Laryngoscopy: time to shed fresh light?

Comparison of endotracheal intubation time in neutral position between C-Mac® and Airtraq® laryngoscopes: A prospective randomised study

BACKGROUND AND AIMS

In the recent past, many novel devices such as AirTraq^® and C-MAC^® video laryngoscope (VL) have been introduced in an attempt to reduce anaesthetic morbidity and mortality associated with difficult intubation. In this study, we aimed to evaluate and compare C-MAC^® VL with a standard Macintosh blade and the AirTraq^® optical laryngoscope as a intubating devices with the patient's head in neutral position.

METHODS

Sixty American Society of Anesthesiologist Physical Status I-II patients were randomly assigned to be intubated with C-MAC^® VL (Group CM; n = 30) or AirTraq^® (Group AT; n = 30) in the neutral position, with or without the application of optimization manoeuvres. The primary outcomes of this study were the success rate and the time taken to intubate. Glottic view, ease of tracheal intubation and haemodynamic responses were considered as secondary end points.

RESULTS

The incidence of successful intubation was similar in both the groups (P = 1.00). However, the time for intubation was significantly less with C-MAC^® VL (Group CM = 14.9 ± 12.89 s, Group AT = 26.3 ± 13.34 s; P = 0.0014). There was no significant difference between the two groups in terms of ease of intubation and glottic view. However, the haemodynamic perturbations were much less with C-MAC^® VL.

CONCLUSION

We conclude that both the devices were similar in visualising larynx in the neutral position with similar success rates of intubation. However, the C-MAC^® VL was better with respect to intubation time and haemodynamic stability.

The Development and Preliminary Evaluation of a Proposed New Scoring System for Videolaryngoscopy

Clear documentation of anaesthetic technique, difficulties and complications is an essential part of good anaesthetic practice, particularly in the area of airway management. The current convention of describing intubation using a videolaryngoscope only in terms of a Cormack and Lehane score is at best unhelpful and at worst dangerous. In an attempt to address the inadequacy of a Cormack and Lehane score to describe videoscopic intubation, we propose a three part scoring system: view, ease and device - the ‘Fremantle Score’. Preliminary evaluation of this system in a diverse group of anaesthetists utilising four available videolaryngoscopes in a simulated normal and difficult airway manikin has demonstrated that the system is easy to use, easy to understand and relevant.

In three of the eight device and manikin combinations studied, the videolaryngoscopic view correlated with the ease of intubation. This highlights the need for an alternative tool to describe intubation with a videolaryngoscope.

We consider this development of a specific videoscopic scoring system a first step in better describing intubation by a videolaryngoscope and improving patient care.