Simple face mask (Hudson mask) can deliver maximum FiO2 of:-: (A) 0.6, (B) 0.4, (C) 0.8, (D) 1
Answer is A. Simple facemask/ 'Hudson' mask These devices are used very commonly. They are variable performance devices and the maximum inspired oxygen concentration that can be achieved with these devices is up to 60%, but this is very dependent on the oxygen flowrate and the patient's respiratory pattern. The mask has side holes which are designed to allow indrawing of room air during inspiration