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6.3.12.3.4
Pi Max
The Pi Max or NIF (negative inspiratory force) is only available for spontaneous modalities and is used
to assess inspiratory muscle strength during the weaning process of mechanical ventilation.
Before beginning the maneuver, orient the patient to make the maximum inspiratory effort possible as
soon as it is requested.
For this maneuver it is necessary to keep the START button pressed during the entire process.
Once the maneuver is initiated, the PEEP value will be temporarily reset, and the inspiratory branch
occlusion will occur.
The negative pressure values relative to the patient's inspiratory effort will be measured to the limit of
-60 cmH2O.
The best value reached will always be displayed in the table to the left of the pressure chart, i.e. the
largest pressure drops identified.
6.3.12.3.5
Gas Trapping Volume
The trapped volume is only available for assisted-controlled modes.
An unwanted volume of air may eventually become trapped in the lungs in cases of pulmonary
hyperinflation or when the interval between breaths is not enough for complete patient expiration to re-establish
the balance of the respiratory system. Most notably, when the presence of intrinsic PEEP is detected.
To accomplishment this procedure, it is ideal that the patient does not exert respiratory efforts.
Therefore, it is recommended that the operator advises the patient if the patient is conscious.
To perform the maneuver, simply press START and then, with each cycle, the ventilator will compare
the target volume value (desired) and the total volume value reached.
6.3.12.4 Trend
By pressing this button, the trend settings will be displayed. The trend holds up to 240 hours of
ventilation.
6.3.12.5 Calibration
Pressing this button displays the available calibrations: O
2
, CO
2
and touch. To perform the calibration,
put the equipment in Standby mode and select the item you want to calibrate.
