when do you use a non rebreather mask
Non-rebreather mask A non-rebreather mask (NRB, non-rebreather, non-rebreather facemask, etc.) is a device used in medicine to assist in the delivery of oxygen therapy. An NRB requires that the patient can breathe unassisted, but unlike low flow nasal cannula, the NRB allows for the delivery of higher concentrations of oxygen.