Dimensional compatibility of rigid ventilating bronchoscopes with pediatric airway anatomy using different recommendations for age-related sizing-A bench study.

Based on this in vitro study, most of the recommendations analyzed result in a balanced fit of rigid bronchoscopes within the cricoid. Since the left mainstem bronchus is considerably smaller than the cricoid, any insertion on this level will require careful endoscopic guidance to avoid damage to the left mainstem bronchus.