Blenders

Question 1

define oxygen mixing device and its purpose

Answer 1

a device which mixes 2 or more gases (one is oxygen) at controlled concentrations

purpose is to provide means of blending gases at specific FiO2 for pt delivery.

Question 2

4 types of oxygen mixing devices

Answer 2

1. oxygen adder
   - e.g. manual resuscitator; air; tandem
2. entrainment devices
   - e.g. venturi systems
3. precision metering devices
   - e.g. bird mark 2
4. oxygen controllers (Blenders)
   - e.g. bird blender

Question 3

bird mark 2 precision metering device

Answer 3

control knob adjusts positioning shaft to move double ended tapered needle valve to control amount of air or oxygen coming through orifice seats to create desired mixture

Question 4

purpose of bleed

Answer 4

when flow meter attached to blender, the bleed helps to ensure accuracy of FiO2 at flows down to 2 LPM

bleed constant at 10-12 LPM of mixed gas

Question 5

flow rates for blender

Answer 5

2-120 LPM