Applied forces with direct versus indirect laryngoscopy in neonatal intubation: a randomized crossover mannequin study

Purpose: In adult mannequins, videolaryngoscopy improves glottic visualization with lower force applied to upper airway tissues and reduced task workload compared with direct laryngoscopy. This trial compared oropharyngeal applied forces and subjective workload during direct vs indirect (video) laryngoscopy in a neonatal mannequin. Methods: We conducted a randomized crossover trial of intubation with direct laryngoscopy, straight blade videolaryngoscopy, and hyperangulated videolaryngoscopy in a neonatal mannequin. Thirty neonatal/pediatric/anesthesiology consultants and residents participated. The primary outcome measure was the maximum peak force applied during intubation. Secondary outcome measures included the average peak force applied during intubation, time needed to intubate, and subjective workload. Results: Direct laryngoscopy median forces on the epiglottis were 8.2 N maximum peak and 6.8 N average peak. Straight blade videolaryngoscopy median forces were 4.7 N maximum peak and 3.6 N average peak. Hyperangulated videolaryngoscopy median forces were 2.8 N maximum peak and 2.1 N average peak. The differences were significant between direct laryngoscopy and straight blade videolaryngoscopy, and between direct laryngoscopy and hyperangulated videolaryngoscopy. Significant differences were also found in the top 10th percentile forces on the epiglottis and palate, but not in the median forces on the palate. Time to intubation and subjective workload were comparable with videolaryngoscopy vs direct laryngoscopy. Conclusions: The lower force applied during videolaryngoscopy in a neonatal mannequin model suggests a possible benefit in reducing potential patient harm during intubation, but the clinical implications require assessment in future studies. Registration: ClinicalTrials.gov (NCT05197868); registered 20 January 2022