If you add flow from an alternative source to PB 840 or Servo 300, the expiratory TV reads higher. Is this due to added flow to expiratory sensors, or actual addition to VT?
Oh but forgot. During the insp time, when the exp valve is closed, the flow will be part of the VT. So if the insp time is 1.0 seconds and the flow is 10 liters/min then you'll get a VT addition--gee it's late and I think it's 167cc's?. But during the exp time that same flow is going and then that will be displayed as well. So the displayed VT is then the vent VT, the insp time addition to the VT, and the "fools gold" VT during the total exp time.
Posts: 171 | Location: Palo Alto, CA USA | Registered: November 14, 2002
dentonrrt Junior Member Posted March 01, 2010 02:01 PM If you add flow from an alternative source to PB 840 or Servo 300, the expiratory TV reads higher. Is this due to added flow to expiratory sensors, or actual addition to VT? Posts: 1 | Registered: March 01, 2010
JeffWhitnack Member
Posted March 02, 2010 04:06 AM Hide Post Both. Flow is just volume over time. Posts: 171 | Location: Palo Alto, CA USA | Registered: November 15, 2002
Ignored post by JeffWhitnack posted March 02, 2010 04:06 AM Show Post
JeffWhitnack Member
Posted March 02, 2010 04:11 AM Hide Post Oh but forgot. During the insp time, when the exp valve is closed, the flow will be part of the VT. So if the insp time is 1.0 seconds and the flow is 10 liters/min then you'll get a VT addition--gee it's late and I think it's 167cc's?. But during the exp time that same flow is going and then that will be displayed as well. So the displayed VT is then the vent VT, the insp time addition to the VT, and the "fools gold" VT during the total exp time. Posts: 171 | Location: Palo Alto, CA USA | Registered: November 15, 2002
Ignored post by JeffWhitnack posted March 02, 2010 04:11 AM Show Post
[QUOTE]Originally posted by dentonrrt: If you add flow from an alternative source to PB 840 or Servo 300, the expiratory TV reads higher. Is this due to added flow to expiratory sensors, or actual addition to VT? [This is a very Old concept and I believe if we search the Artifacts we should find older discussions on this Topic.]
Posts: 8 | Location: Chicago,ILL.USA. | Registered: April 08, 2003
Ofcourse it will, but the actual VT the patient received can not be measured, I think the actual VT is between the VTi and VTe, so most ventilator manufactures do not suggest adding foreign flow into ventilator system. For doing this will disturbance the normal work of ventilator.