Adequately delivering heated and humidified gas at flows up to 60 L/min to:
Reduce inspiratory resistance and work of breathing by providing airway stenting
Improve work of breathing by washing out anatomical dead space from the upper airway
Improve oxygenation
Increase mucociliary clearance by possibly providing air with 100 % relative humidity
Indications
Hypoxemia
Hypercapnia
Tachypnea
Accessory muscle use
Grunting
Nasal flaring
General
The max size of prong to use with each patient is one not to occlude greater than 50% of the internal diameter of each of the nares
If flow has been increased too high
If the patient starts to have more of a forced exhalation
With auscultation, there will be a quieter expiratory flow than in previous assessments at lower flows
The heater should be set in the invasive mode while using the HFNC, unless the patient cannot tolerate the temperature
Once at 2 L/pm switch to 2 L/min off the wall (NO BLENDER), except NICU
The FiO2 is titrated with an Oxygen Blender so can be 21-100%
Size - Color - Min-Max Flows
XS - Blue - 0.5-8 L
Small - Red - 0.5-9 L
Medium - Yellow - 0.5-10 L
Large - Purple - 0.5-23 L
XL - Green - 0.5-25 L
XXL - Optiflow (Gray) - up to 50 L
Special Considerations
Each of the above nasal cannulas sizes is rated at a flow rate because if you try and push a higher flow rate through it than is allowed, the back pressure produced in the system will be higher than 40 cmH20 and thus any flow over the rating will escape or be released through the pop-off into the room.
The white manifold has a built-in pop-off valve that typically is set to pop-off (release) any flow that produces a pressure of 40 cmh20 or higher in the circuit. No alarms will sound and nothing will tell you that the patient is not actually receiving the flow rate that is on the flow meter
Floor Specifics
No more than a required FiO2 of 50%
Weight vs Max Flow per Pathway
Less than 7 kg - max flow is 8 L
7-9 kg - max flow is 10 L
Greater than 9 kg - max flow is 12 L
If on greater than 50% FiO2 and/or greater than the max flow allowed, the patient’s attending needs to evaluate for escalation of the level of respiratory support and a higher level of care.