Clinical evaluation of Ambu ® Aura-i™ - A new intubating laryngeal mask airway as an independent ventilatory device and a conduit for tracheal intubation in pediatric patients.

BACKGROUND: Ambu® Aura-i™, a recently introduced second generation supraglottic airway device has been designed to function as an independent ventilatory device as well as a conduit for passage of conventional cuffed tracheal tubes through it. There is dearth of literature on experience of tracheal intubation through intubating laryngeal mask airway (ILMA) in paediatric age group. This study was conducted to study the ventilatory effectiveness and the intubating characteristics of Ambu® Aura-i™ in paediatric patients.

AIM: To study the effectiveness of Ambu ® Aura-i ™ as a supraglottic device for its ventilatory effectiveness and intubation characteristics in paediatric patients.

OBJECTIVES: To study the Ventilatory effectiveness of Ambu ® Aura-i ™ in terms of: 1) Time taken in insertion of Ambu ® Aura-i ™. 2) No of attempts made for successful insertion of Ambu ® Aura-i™. 3) Tidal volume attained on positive pressure ventilation. 4) Etco2, Spo2 and Leak pressure achieved. To study the Intubating characterstics of Ambu ® Aura-i ™ in terms of :- 1) Grade of alignment of the ventilating orifice achieved in relation to the larynx in the fibre optic view. 2) Time taken in intubation through Ambu ® Aura-i ™. 3) Number of attempts made in intubation. 4) Time taken for removal of the Ambu ® Aura-i ™ after intubation through it has been accomplished.

METHOD: Sixty three children undergoing elective surgery under general anaesthesia requiring intubation of trachea, weighing between 5-30 kg were stratified into 3 groups (n= 21) each. Ambu® Aura-i™ size 1.5 , 2.0 ,2.5 were used based on their body weight for airway management. Ventilatory effectiveness was studied in terms of success rate, number of attempts made at insertion, time taken in insertion, tidal volume delivered and leak pressure achieved. Intubating characterstics studied during fibreoptic guided tracheal intubation included grade of alignment of the ventilating orifice achieved in relation to the larynx in fibre optic view, time taken in fibreoptic guided tracheal intubation, success rate and number of attempts made at intubation. Time taken in removal of the device and complications observed were also recorded.

RESULTS: Ambu® Aura-i™ insertion, fibreoptic guided tracheal intubation and device removal were successful in all the patients in first attempt. The mean time taken in successful device insertion was 10.83±2.04 sec. The mean tidal volume delivered was 7.88±1.33 ml/kg body weight and mean leak pressure achieved was 16.27±5.2 cm H2O. The fibreoptic guided intubation was possible in first attempt in 100% of the patients (n=63). The Fibre optic view was grade 1 in 82.55% patients (n=52 /63) and grade 2 in 17.46% (n=11/ 63) patients. The mean time taken in fibre optic guided intubation was 12.68 ±2.82 sec. The mean time taken in removal of the device over the tracheal tube was 12.27 sec. There was no significant incidence of trauma to soft tissues, sore throat, laryngospasm or hoarseness of voice.

CONCLUSION: On the basis of observations of this study, we conclude that Ambu ® Aura-i ™ is not only an effective ventilatoy device, but also an excellent conduit for fibre optic guided intubation using conventional uncuffed endotracheal tube in paediatric patients. Ambu ® Aura-i ™ , is also valuable for establishing rapid airway access in emergent difficult paediatric airway.