Abstract: A neonatal suction adaptor with reduced deadspace allows tidal volume monitoring and synchronization to continue without substantial interference while a suction catheter is used. The adaptor includes a central housing disposed about a central chamber. A ventilation connector and an endotracheal connector are each secured to, and extend from, the central housing. Each tubular connector defines a passage connected with the central chamber. The connectors are sized and shaped to form press-fit connections with endotracheal tubes and ventilation monitors. The endotracheal connector includes a sleeve separated from a core by an annular recess configured to receive part of an endotracheal tube ventilation adaptor. A suction access tube is also secured to, and extends from, the central housing. The suction access tube is connectable to a wide variety of standard sleeved or exposed suction catheters.