Comparison of different types of stylets with no-stylet technique for intubation with C-MAC D-Blade® videolaryngoscope in simulated difficult airway: A prospective randomized study

The angulated C-MAC D-Blade videolaryngoscope (VL) is designed for difficult intubation and may not be compatible with standard PVC endotracheal tubes.Present study was planned to compare efficacy of C-MAC, D-blade VL using endotracheal tube with three different stylets versus No stylet in patients undergoing tracheal intubation with simulated difficult airway.After obtaining written consent and IEC approval, total 144 adult patients were allocated to four groups of 36 each using no stylet or different types of stylets. The four groups were Group NS: No stylet; Group CS: C-MAC stylet; Group DS: D-blade type stylet; Group HS: hockey-stick shaped stylet. A rigid appropriate sized Philadelphia cervical collar was placed around the neck to simulate difficult airway and C-MAC D-Blade VL was used for intubation. The duration of each intubation stage and attempts were evaluated. Statistical analysis was performed using SPSS 22.0 for Windows and appropriate tests for different variables were applied. Appropriately, Student's t test, Chi-square test, Mann-Whitney U test and one-way ANOVA test were applied.Similar Cormack Lehane grade glottic view was observed in all groups. The number of attempts and duration of intubation was significantly greater using NS than for other groups. Additional laryngeal manipulation, was required in all cases in Group NS, compared to one, zero and two cases in group CS, DS and HS respectively (p0.001).Use of Hockey stick shaped, D blade shaped stylet and C Mac stylet decreased the total intubation duration in patients with simulated difficult airway.