Evaluating the Usability of a 3D-Printed Video Laryngoscope for Tracheal Intubation of a Manikin

Background: Compared to direct laryngoscopy, videolaryngoscopy (VL) can provide improved laryngeal and glottic view, higher intubation success rates in patients with a known or predicted difficult airway and reduced incidence of laryngeal/airway trauma. However, the cost and availability of these devices handicap its use in resource-restricted facilities. The objective was to design and manufacture a novel VL using additive manufacturing (AM) and evaluate its usability on an intubation manikin by comparing it to one of the most common video laryngoscopes used in clinical practice, the CMAC (R), by measuring the time to first pass of the endotracheal tube as the main outcome. Methods: A randomised cross-over study was performed with 36 anaesthetists attempting tracheal intubation of a manikin. The novel 3D-printed hyperangulated VL blade was compared to a CMAC (R) VL (D-blade). Participants had no prior experience or training with the novel device. The participants included consultants, registrars/trainees and medical officers in the Department of Anaesthesiology at the University of the Free State (UFS) in South Africa. Results: The CMAC (R) had a statistically shorter time to first pass (median 13.8 seconds) compared to the 3D-printed model (median 19.0 seconds) (95% confidence interval [CI] 1.0-6.2; P=0.0013). No failed attempts occurred with either device. Conclusion: Intubation times were faster with the CMAC (R) than with the novel device. However, with a comparable intubation success rate, 3D printing technology potentially can improve access to video laryngoscopy. Further design improvements, validation of materials and manufacturing processes are required before 3D-printed laryngoscope blades can be used in human subjects.