Question: I have some questions regarding supplemental oxygen. For a patient who requires oxygen, but is vomiting frequently is a nasal cannula an adequate oxygen delivery system, or should a Non Rebreather be continually removed an reapplied as necessary? Also I see a wide range of flow rates applied to the nasal cannula (anywhere from 2-8 lpm). What flow rate is most beneficial to a patient in a pre-hospital setting who requires supplemental oxygen via nasal cannula?