Evaluation of the Ambu aScope, a new single-use flexible videoscope
MV Kumar, A Clarke, AR Wilkes, N Goodwin, I Hodzovic
Anaesthetics, Intensive Care and Pain Medicine,
Cardiff University, Cardiff CF14 4XN
Fibreoptic scopes (FOS) are well established in the management of difficult airways [1]. However these reusable devices need to bedisinfected before each use. This cleaning process can take 20-60 minutes to complete [2]. In addition, some contamination may remain
despite cleaning [3]. Ambu aScopeTM is a recently introduced flexible videoscope. This portable, light-weight, single-use device has notbeen evaluated before. We therefore decided to compare the handling and ease of use of the Ambu aScope (Ambu) against an Olympus reusable fibreoptic scope (Olympus).
Methods
We invited 75 anaesthetists to take part in this randomised cross-over study. Each volunteer was asked to place the FOS via the nasal routein the trachea of the AirSim Multi manikin (Trucorp Ltd). The manikin was modified by narrowing the airway in three places. A video of
the fibreoptic view was recorded. We measured the time to complete the task (from handing the scope to the time the tip of the scope
appeared through the left main bronchus), user device preference and volunteer’s impression on the ease of use (VAS: 0mm-extremely
difficult, 100mm-extremely easy). The volunteers were asked to do the task twice with each scope. Two members of the research teamindependently counted the number of tip surface collisions (a complete red out on the screen) three times from each of the video
recordings. We used SPSS v16 to analyse the data.
Results
The median (IQR) number of years of anaesthetic experience of the volunteers was 9 (5-15) years. The main findings of the study arepresented in the table.
Table: Values are mean (SD), proportion (%) as appropriate. (n = 75)
Olympus
Ambu
Diff [95% CI]
P-value
Completion
time; s63 (31) 10 [3 to 17]
0.008
1st attempt 53 (23)48 (23)
6 [2 to 11]
0.010
2nd attempt 41 (19)
Tip collisions
st2.7 (1.9) 0.2 [-0.4 to 0.7] 0.56
1 attempt 2.5 (1.8)
2.6 (2.0) 0.0 [-0.4 to 0.5] 0.89
2nd attempt 2.6 (1.8)
77 (14)65 (18) -12 [-7 to -17]<0.001Ease of use
VAS; mm57 (76%)
18 (24%)<0.001
Preference
Discussion
This study found a significant difference in the time to task completion between the Ambu and Olympus scopes. However, there was nodifference in the number of tip surface collisions between the two scopes. It is debatable which of the two outcomes is more relevant
clinically. The participants found the Olympus significantly easier to use and preferred this device to the Ambu scope: they stated thefamiliarity and ease of manoeuvring the tip of the scope as their reason for this. Clinical studies are needed to further evaluate the place ofthe Ambu scope in the management of difficult airway.
References
1.
Henderson JJ, Popat MT, Latto IP, Pearce AC. DAS guidelines for management of the unanticipated difficult intubation Anaesthesia
2004; 59: 675-94
2.
British Thoracic Society guidelines on diagnostic flexible bronchoscopy. Thorax 2001; 56: i1-i21
3.
Reeves DS, Brown NM. Mycobacterial contamination of fibreoptic bronchoscopes. Journal of Hospital Infection 1995; 30: 531-6