A Comparative Study of Airtraq Versus Macintosh Laryngoscope for Endotracheal Intubation by First Year Resident

This study evaluates the learning and performance of tracheal intubation by first year anaesthesia trainee in Nepalese population using either Airtraq or Macintosh laryngoscopes.

The airway is primarily a conduit for air to reach the lungs. Maintaining a stable, patent airway is a fundamental element of safe perioperative care for all anesthesiologists. Though maintaining airway patency seems conceptually straightforward, a wide variety of clinical circumstances, patients, and tools can make the task of ensuring a stable, open airway under all clinical conditions extremely challenging.

In spite of endotracheal intubation being a lifesaving skill, problems like delayed intubation, misplaced tracheal tube, or airway trauma are frequently encountered, and can cause death or hypoxic brain damage. The magnitude of problems during airway management constitute 17% of anaesthesia closed claims in UK, with difficult intubation being the most common at a rate of 5%.The American Society of Anesthesiologists' Closed Claims Project (ASACCP) reports that though the proportion of claims for respiratory complications decreased from 34% in the 1970s to 15% in the 1990s, the 'big three' (inadequate ventilation, oesophageal intubation, and difficult tracheal intubation) still accounted for \>50% of claims leading to death or permanent brain damage.

Direct laryngoscopy (DL) remains the gold standard technique for securing the airway. Successful DL involves the creation of a new (non-anatomic) visual axis, through maximal alignment of the axes of the oral and pharyngeal cavities and displacement of the tongue that requires manipulations of head, neck and larynx and other stressful movements. These manipulations of the airway have numerous adverse implications including significant hemodynamic disturbances, cervical instability, injury to oral and pharyngeal tissues, and dental damage. It is thus, a complicated technical skill with a variable learning curve and requires regular training, experience, and practice to acquire and maintain.

The video laryngoscope (VL) is a recently developed device with a camera and light source on the tip of its blade that provides indirect glottic view. The Airtraq laryngoscope is a recently developed video laryngoscope. It has an anatomically shaped blade which contains two parallel channels, one, the guiding channel, for the insertion of the endotracheal tube (ETT) and the other, the optical channel, containing a series of lenses, prisms, and mirrors that transfer the image from the illuminated tip to a proximal viewfinder, giving a high-quality wide-angle view of the glottis and surrounding structures.

As compared to DL, Airtraq VL requires the application of lesser force to the base of the tongue and is thus less likely to stimulate stress response and induce local tissue injury, produces less cervical movement, and has a faster learning curve relative to DL. It has also been demonstrated to be beneficial in the difficult airway scenario, when compared with the Macintosh laryngoscope, by reducing the number of failed intubations, the duration of intubation attempts and the amount of airway manipulation required, making them suitable for use by medical personnel who intubate infrequently.

The purpose of this study is to evaluate learning and performance of tracheal intubation by first year anaesthesia trainee using either Airtraq VL or Macintosh laryngoscopes.

Eligibility Criteria:
Inclusion Criteria:

1. ASA physical status I and II
2. Age group 16-65 years of either gender
3. Patient requiring orotracheal intubation under general anaesthesia.

Exclusion Criteria:

1. Patient having respiratory tract (oropharynx, larynx) pathology,
2. Patient with predicted difficult airway (such as mouth opening \<2 cm),
3. Patient having gastroesophageal reflux disease, hiatus hernia, and pregnancy.