An artificial airway device to facilitate a patient's lung ventilation comprising at least one airway tube and a mask at one end of the airway tube, the mask having a peripheral formation capable of conforming to, and fitting within, the actual and potential space behind the patient's larynx to form a seal around the circumference of the laryngeal inlet, the peripheral formation surrounding a hollow interior space or lumen of the mask and the airway tube opening into the lumen of the mask, wherein the mask provides a space for drainage of gastric matter leaving the oesophagus, such space being an internal volume of the mask and providing a conduit having a volume large enough to effect a significant rise in the pressure of fluid emerging from the oesophageal sphincter while still providing an inflatable mask shape maintaining the seal around the circumference of the laryngeal inlet.