Fig. 2From: Ease and difficulty of pre-hospital airway management in 425 paediatric patients treated by a helicopter emergency medical service: a retrospective analysisTube depth of insertion (cm) for patient age (years). Filled triangle = primary mission; filled dot = secondary mission; yellow line = depth of insertion (10.612 + age [years] × 0.5493 in cm) according to Weiss et al. [31] Red line = depth of insertion according to formula (12 + [years] × 0.5 in cm) [35]Back to article page