Kim YM, et al. - High-flow nasal cannula oxygen (HFNC) creates a positive pressure effect through high-flow rates compared with conventional oxygen therapy. Researchers investigated the effects of HFNC vs conventional oxygen therapy on the rate of carbon monoxide (CO) clearance from the blood in patients with mild to moderate CO poisoning. In this human pilot study, CO-poisoned patients randomly assigned to receive 100% oxygen from a rebreathing reserve mask (NBO ₂, flow of 15 L/min) or HFNC (flow of 60 L/min). They identified a total of 22 patients who had fraction of COHb value (fCOHb) levels ≥ 10% at the time of ED arrival; 9 of these had fCOHb level ranging between 25% and 50%. No reduction in half-life time of fCOHb (fCOHb t _1/2) was observed with HFNC therapy vs NBO ₂ therapy. However, HFNC therapy seemed to be beneficial in maintaining a constant fCOHbt _1/2 as well as in reducing fCOHbt _1/2 in mild CO poisoning patients compared with conventional NBO ₂ therapy.