Visual recognition of anatomical structures in a circulated and in a non-circulated airway

Pre-hospital airway management is complex and complications occur frequently. Guidelines advice using waveform capnography to confirm correct tube position, but in the emergency setting this is not universally available. Continuous visualization of the airway with a video tube (VivaSight SL™) could serve as an alternative confirmation method, provided that airway structures are properly recognized. With this study we wanted to investigate whether airway management practitioners were able to recognize anatomical structures both in a circulated and in a non-circulated airway.

Ten staff anesthetists, ten trainee anesthetists and ten paramedics were asked to examine four pictures of a circulated airway, obtained in a healthy patient and four pictures of a non-circulated airway, obtained in a human cadaver. Correct recognition of the tube position in the airway was scored.

Anatomic structures in the circulated airway were more often recognized than in the non-circulated airway, 90% vs. 43% respectively (P<.001). Overall, anesthetists performed better than paramedics (P=.009), but also when only pictures of the non-circulated model were taken into account (P=.007). The majority of participants and all staff anesthetists correctly recognized the vocal cords in both the circulated and non-circulated airway.

Pictures of a circulated airway were more often recognized than of a non-circulated airway and personnel with a daily routine in airway management performed better than personnel with less frequent exposure. Future research should determine whether continuous visualization of the airway with a video tube could reduce the number of misplaced tracheal tubes in pre-hospital airway management.