Effect of cricoid force on airway calibre in children: a bronchoscopic assessment

Cricoid pressure or to be more exact cricoid force (CF) can cause airway obstruction and subsequent difficulty with airway management during an emergency induction. We studied 30 children with an age range of 3 months to 15 yr who presented for routine bronchoscopy or other surgical procedures requiring tracheal intubation. We looked at the effect of CF on the calibre of the subglottic airway and objectively measured the force which caused 50% or greater distortion/compression of the subglottic airway. There was a linear relationship between both age and weight and CF. No patient suffered any adverse effects. Overall, the mean force required to compress the airway was 10.5 N. However, this force could be as low as 5 N in children < 1 yr of age, and up to between 15 and 25 N in teenagers. Forces well below the recommended value of 30 N will cause significant compression/distortion of the airway in a child.