Philips V200 manual Special Procedures, Auto-PEEP Calculation

Chapter 8

Operating Instructions

Special Procedures	Auto-PEEP Calculation
	The ventilator allows the operator to calculate Auto-PEEP from an expiratory
	hold procedure. This function is active only at the end of a mandatory breath
	and is not available in the emergency ventilation mode. Expiratory hold is
	initiated by pressing the EXP HOLD key on the front panel. When exhalation
	ends in the breath during which the EXP HOLD key is being pressed, an
	expiratory hold maneuver will begin and will continue only as long as the key is
	pressed. During the expiratory hold maneuver, the screen shown in Figure 8-35
	below will appear.

Pressure versus time waveform.

Figure 8-35: Expiratory Hold Maneuver

While the EXP HOLD key is held, the exhalation valve and the air and O2 valves will be closed. During this period there is no flow of gas into or out of the patient circuit from the ventilator. You can monitor the airway pressure by watching the EXPIRATORY PAUSE PRESSURE digital display, and by watching the pressure versus time waveform. When you determine the airway pressure has stabilized, the EXP HOLD key should be released. If the key is held for 5 seconds, the ventilator will automatically terminate the maneuver and perform the calculation if stability was achieved. The ventilator then calculates Auto- PEEP as shown in the equation below:

•Auto-PEEP = Expiratory Pause Pressure - End Expiratory Pressure

NOTE:	If the EXP HOLD key is held continuously, and the expiratory
	hold maneuver exceeds 5 seconds, the ventilator automatically
	terminates the expiratory hold maneuver and begins a new
	inspiratory period.
NOTE:	If Auto PEEP as calculated in Equation 1: Auto-PEEP = Expiratory
	Pause Pressure – End Expiratory Pressure, is negative, Auto-PEEP will
	be displayed as “—.”

REF 1057983 A Respironics V200 Ventilator Operator’s Manual 8-31