The aim of this study was to determine feasibility for a larger definitive trial, focusing on first-pass intubation success rates. A first-pass intubation success rate of less than 85% would be required to produce a clinically viable, adequately powered study. This pilot study revealed an overall first-pass success rate of 78%, indicating that a larger trial assessing a robust endpoint of first-pass success is feasible.
Key Findings:
- First-Pass Success Rate: The study found an overall first-pass success rate of 78%, which is below the 85% threshold considered necessary for a clinically viable study.
- Comparison Between VL and DL: A recent meta-analysis found no significant difference in first-pass success rate between VL and DL, with an overall first-pass intubation rate of 84%. However, there was a moderate level of bias due to heterogeneity of the included trials.
- Time to Successful Intubation: The pilot study showed a significantly longer time to successful intubation using VL, which may be clinically significant in patient populations with high metabolic requirements.
- Operator Experience: The study used a minimum of 20 intubations as the operator exclusion criteria, acknowledging the potential for operator bias but emphasizing the need for a range of operator experience to appropriately test effectiveness.
Limitations:
- The trial design had several limitations, including the impossibility of blinding the operator from the technique being used, which could be a potential source of operator bias.
- The study did not routinely use neuromuscular monitoring to assess the degree of motor blockade prior to intubation, reflecting regular clinical practice but acknowledging this as a limitation.
- The Intubation Difficulty Scale (IDS) used to compare DL and VL may not be the optimal comparison tool, as it has not been validated for use in VL.
Conclusion: The pilot study demonstrated that a larger trial assessing first-pass intubation success rates is feasible. The findings suggest that further research is needed to assess the effectiveness of VL and DL, taking into account operator experience and potential biases. The study also highlighted the need for a validated scoring system to assess intubation difficulty using indirect videolaryngoscopes.