Table 2.
Action | PS effect | PH effect |
---|---|---|
Increase ventilator pressure control (PC) | Decrease EtCO2 | Decrease EtCO2 |
Decrease ventilator PC | Increase EtCO2 | Increase EtCO2 |
Increase ventilator positive end expiratory pressure (PEEP) | Minimal increase EtCO2 | Minimal increase ETCO2 |
Decrease ventilator PEEP | Minimal decrease EtCO2 | Minimal decrease EtCO2 |
Decrease PH’s FRE resistance | No effect | Decrease EtCO2 |
Increase PHs FRE resistance | No effect | Increase EtCO2 |
Increase ventilator I-time | Decrease EtCO2 | Decrease EtCO2 |
Decrease ventilator I-time | Increase EtCO2 | Increase EtCO2 |
For the standard MPVC setup, PS has the proximal line attached to give feedback to the ventilator (I.e., the three-way flow valve is turned to monitor PS). Each patient has their own FRE; however, adjusting the PS’s FRE has no effect since the proximal line is monitoring that patient. Thus, the FRE on the PH circuit is the only FRE that should be adjusted unless the patient’s lung compliances are switched