A bi-directional oxygenation apparatus for a patient includes a mouthpiece including an intraoral portion for placement in the patients mouth and defining a center orifice, the mouthpiece including an external portion coupled to the intraoral portion and in fluid communication with the center orifice. A valve port includes a continuous side wall operatively coupled to the external portion of the mouthpiece and defining an interior area in fluid communication with the center orifice, the valve port selectively moved toward or away from the external portion when air is inhaled or exhaled through the center orifice, respectively. A one-way positive-end expiratory pressure (“PEEP”) valve is situated in the interior area of the valve port and configured to resist air exhaled by the patient through the center orifice.
