Disclosed is an oxygen delivery apparatus constructed from an oxygen delivery manifold, a respiratory cannula, and a host controller. The host controller contains an oxygen delivery program and accepts a respiration input regarding whether the patient is inhaling or exhaling, and whether the patient is breathing orally or nasally. The oxygen delivery program regulates the flow rate of oxygen based in part upon the respiration input provided. A first rates is used when the patient is inhaling and exhaling orally, a second rate is used when the patient is inhaling nasally, and a third rate is used when the patient is exhaling nasally.