Paediatric airway management: bringing dead space back to life

Dead space is the portion of each breath that does not participate in gas exchange and is a fundamental but frequently misunderstood concept in paediatric airway management. While anatomical and alveolar dead space are fixed physiological factors, apparatus dead space added by airway equipment is modifiable, yet often overlooked in emergency settings where adult-sized components may default into use. Because paediatric tidal volumes are small, even modest additional apparatus dead space can disproportionately reduce effective alveolar ventilation, risking hypercapnia despite visible chest rise or a reassuring capnography trace. Using simplified worked calculations, this article offers clinicians and educators a straightforward way to understand dead space and effective alveolar ventilation, and to examine their own equipment, training systems and default airway-management practices.