Parameter Monitoring (Waveforms) Operations
5 - 20 046-004667-00 A7™ Operating Instructions
FIGURE 5-20 Gas Parameter Group
5.10 Parameter Monitoring (Waveforms)
The system displays waveforms in the waveforms / spirometry area. The waveforms are separated
into four groups: pressure waveform, flow waveform, volume waveform and gas waveform
(available with the AG module).
5.10.1 Pressure Waveform
The Pressure vs. Time waveform displays in the waveform area.
FIGURE 5-21 Example Simulated Pressure vs. Time Waveform
Pressure vs. Time
The Y-axis of the Pressure vs. Time waveform is labeled PAW (which represents Airway Pressure).
The unit of measure is cmH
2
O, hPa, or mbar. The Y-axis automatically adjusts the scales. Though
the X-axis is not labeled, it represents a time scale of 0 to 15 seconds.
NOTE: The purple in the waveform means it is a triggered breath.
5.10.1.1 Auto-zeroing the Pressure Sensors
The A7 auto-zeros the pressure sensors at regular intervals to compensate for changes in
temperature and/or barometric pressure that could affect both pressure and flow measurements.
This may affect the waveforms on the screen, but does not affect the volume/pressure delivered
to the patient.
The auto-zeroing intervals are: startup, 5 mins, 15 mins, 30 mins, 60 mins, and every 120 mins
thereafter.
NOTE: The A7 displays the message “Auto-zeroing in process” during the
auto-zeroing intervals.
5.10.2 Flow Waveform