Evaluation of Ambu® aScope™ 2 in awake nasotracheal intubation in anticipated difficult airway using conventional or facilitated technique: A randomized controlled trial

Objectives
Ambu® aScop2 (aScope2) is a new disposable flexible videoscope, that has several advantages compared with the reusable devices. The purpose of this study was to evaluate the efficacy of this device in awake nasotracheal intubation for patients with anticipated difficult airway and to compare the use of facilitated technique with the conventional technique in an attempt to fasten the nasotracheal intubation and to increase the likelihood of success.
Methods
Fifty adult patients aged 18–45 years of ASA I–III with anticipated difficult intubation were randomly allocated into two groups of awake nasotracheal intubation either by the conventional technique of videoscopic nasotracheal intubation (C group) or by facilitated technique (F group) where a lubricated nasal tube was introduced first into nasopharynx till the mark 18 in males and 16 in females acting as a conduit for the aScope, then the aScope 2 was inserted through it to visualize the vocal cords and then advanced into the trachea, finally the nasal tube railroaded over the aScope. Times needed to visualize vocal cords (Tvc), to complete the endotracheal intubation (Tti) and the sum of both were recorded. Also number of attempts, the need of facilitating maneuver, success rate and any complications were compared.
Results
The overall success rate of aScope-guided intubation was 84% and 92% in the control and the facilitated groups respectively with a higher 1st attempt success rate in the facilitated group. Both Tvc and total nasotracheal intubation time were significantly shorter in facilitated group (156 ± 0.81 and 198.6 ± 0.82 s) compared to (201.6 ± 1.15 and 244.8 ± 1.15 s) in control group.
Conclusion
The aScope 2 provided a high success rate in awake nasotracheal intubation in patients with anticipated difficult airway and the use of a facilitated technique shortened the time needed to perform successful videoscopic intubation.