MAP:Mean Airway Pressure
This is the pressure at which the alveoli constantly remain open.
Remember, the ventilator can calculate this value for you on CMV, and what we will usually do is see what this measured value is on CMV and
increase it by 1-2 when transitioning to HFOV. MAP is a major
determinant of the infant’s oxygenation, until it compromises cardiac
output and pulmonary blood flow. The general goal when starting an
infant on HFOV is to achieve 9should always get a CXR within 30-10 rib expansion on chest x-60 minutes of putting someone on -ray, so you
HFOV. Because the MAP is directly related to oxygenation, you can
generally clinically correlate with your pulse oximeter readings.
ΔP:Amplitude
This is the degree of oscillation within the circuit around the MAP you’ve
chosen. It is directly related to CO2 removal, and is the parameter you adjust when ventilation is a problem. This is also the setting that
determines how much the baby’s chest is vibrating. Some people like to
keep the MAP and ΔP in a 1:2 or 1:3 ratio, so after you’ve chosen your
MAP, you can usually multiply that number by 2 or 3 to get a start point for your ΔP. Ultimately, though, you need to use whatever ΔP it takes toachieve good chest vibration.^
Hz:Hertz
In physics, this is defined as cycles/second. This is the number of oscillations that occur
around the MAP in any given second. A Hz
of 10 equals 600 cycles/second. This value
is rather fixed and isn’t chanHFOV is underway, except in circumstancesged much once
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MAP
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Hz