Hyperangulated videolaryngoscope for difficult airway management: a protocol for a systematic review with meta-analysis and trial sequential analysis.

Introduction: Videolaryngoscopes are recommended as the top preference for tracheal intubation in adults, children, infants and neonates, and even in patients with anticipated difficult airways, since they are generally easier to use and quicker to master than fibreoptic bronchoscopes. Compared with standard videolaryngoscopes, hyperangulated videolaryngoscopes possess a more sharply curved blade or blade tip, resulting in a higher first-attempt success rate among patients with anticipated difficult airways. However, hyperangulated videolaryngoscopes also pose challenges in advancing the tracheal tube, which decreases the first-attempt success rate while increasing the tracheal intubation time when the tracheal tube introducer is unsuitable. Hence, controversy still remains regarding the efficiency of hyperangulated videolaryngoscopes as first-line devices in patients with anticipated difficult airways, owing to the inconsistent clinical findings. Consequently, we will conduct a protocol for a systematic review and meta-analysis to determine the usefulness of hyperangulated videolaryngoscopes in patients with anticipated difficult airways.

Methods And Analysis: English-language databases (Web of Science, Cochrane Library, PubMed, Embase and Ovid Medline), Chinese electronic databases (VIP database, China National Knowledge Infrastructure, and Wanfang database) and clinical trial registry platforms will be scoured from their inception to May 2025 to locate randomised controlled trials of hyperangulated videolaryngoscopes in patients with anticipated difficult airways. For continuous data, mean differences or standardised mean differences, accompanied by their 95% CIs, and for dichotomous data, the risk ratio, accompanied by its 95% CI, will be calculated using Review Manager V.5.4. Either a fixed-effects model or a random-effects model will be used depending on the magnitude of statistical heterogeneity as evaluated via the I test. The risk of bias will be assessed via the Cochrane risk-of-bias tool 2. Additionally, the quality of evidence regarding each outcome will be evaluated using the Grading of Recommendations Assessment, Development and Evaluation. The reliability of all outcomes will be appraised via trial sequential analysis. Moreover, the publication bias of all outcomes will be examined using Funnel plots and Egger's regression test.

Ethics And Dissemination: Ethical approval was not required for this systematic review protocol. The results will be disseminated through peer-reviewed publications.

Prospero Registration Number: CRD42024627484.