Quest for an Ideal Intubating Device

Abstract

The first scientific report of tracheal intubation and artificial respiration is attributed to Vesalius, who in 1543 performed this in animals. The first perioperative use of tracheal intubation was described by Macewen in 1880 to prevent aspiration during the removal of a tumor from the base of the tongue. However, regular perioperative use of tracheal intubation in anesthetized patients started only in the early 1900s. Until then, even oral surgery was performed without a definitive airway, thus predisposing patients to the risk of aspiration. As the use of tracheal tubes and intubation gained popularity, a proportional need to develop equipment that could help in placing a tracheal tube into the trachea arose. In 1913, Chevalier Jackson reported a high rate of success for the use of direct laryngoscopy as a means to intubate the trachea. The development of a rigid, curved laryngoscope by Macintosh in 1943, made the process of intubation simpler and less traumatic as it could now be performed under direct vision. Development of anesthetic drugs that rendered the patient unconscious within seconds and muscle relaxants that facilitated intubation made direct laryngoscopy and intubation the most followed technique for the establishment of a definitive airway. However, as the technique gained popularity, its limitations also came to the fore. A limited mouth opening (<25 mm) or an anteriorly placed glottis were commonly encountered situations where direct laryngoscopy and intubation was rendered difficult if not impossible. This resulted in the development of several alternatives to facilitate tracheal intubation; such as intubating laryngeal mask airway (ILMA), lightwand, fiberoptic bronchoscope (fiberscope), and video/optical laryngoscopes (such as Airtraq, Glidescope, retromolar scope, bullard laryngoscope etc). While some of these devices permit visualization of the larynx prior to intubation; some, such as lightwand /intubating laryngeal mask airway are semi-blind or blind techniques. Despite manifold advances in the development of airway gadgets and a vast range of available devices, only a few prove useful in patients with limited mouth opening where nasal intubation is required. In my opinion, an ideal intubation device should be versatile enough to aid in securing a definitive airway by both oral and nasal routes, especially in situations that result in failure to intubate with direct laryngoscopy. A plausible exception where even such an ideal intubation device may fail would be in the presence of an infraglottic pathology that prevents the advancement of a tracheal tube beyond the glottis.

Keywords