per chap 11

  1. Define volume ventilator
    A preset VT is delivered to the patient in each machine breath and once delivered inspiration ends
  2. What is volume-limited
    inspiration pressure maintains the preset VT when changes in airway resistance and compliance occur
  3. pressure-cycled ventilator
    Preset inspiratory pressure is delivered to PT once it is reached inspiration ends
  4. In a pressure cycled ventilator what effects the VT?
    It is unknown, it varies with changes in airway resistance and compliance. Volume varies pressure is constant.
  5. On a pressure cycled vent what happens to TV when lung compliance decreases?
    VT decreases as the PT's lungs become stiffer and harder to ventilate
  6. On a pressure controlled vent when inspiratory pressure is increased what happens to the VT?
    It increases
  7. On PCV if the target TV is not reached what should be done to PIP
    Increase the PIP to increase TV
  8. What does it mean when a patient is on PCV and the exhaled VT decreases with no change in vent settings
    Either compliance has decreased or airway resistance has increased
  9. How are Bi-PAP's inspirations triggered?
    either time triggered or patient triggered
  10. what is auto peep
    gas trapped in alveoli at end expiration
  11. Pressure support Ventilation how is it used; indications
    • Can be used alone or with SIMV.
    • PT assisted
    • pressure generated
    • flow cycled breath
    • used to overcome resistance from ET tube
    • PT initiates Insp; preset pressure is reached and held constant until Insp flow is reached then pressure terminated
  12. What are the parameters for determining VT for:
    most PT's
    PT's with ARDS
    PT's with COPD
    • most pt=8-12 ml/kg ibw
    • ARDS= 5-6 ml/kg ibw
    • COPD= 8-10 ml/kg
  13. What is the threshold for static pressure in order to avoid over distention of alveoli and lung damage?
    Less than 35 cm H2O
  14. What is the most effective way to improve alveolar ventilation and decrease PaCO2?
    By increasing TV NOT by increasing Vent rate
  15. What are two solutions to vent pt with high PaCO2?
    Increase the VT and increase the RR.
  16. How does adjusting the RR effect the I:E ratio?
    It effects the expiratory time. Increasing RR decreases E time; decreasing the RR increases the I time
  17. How does adjusting the RR effect the minute volume?
    Increasing the rate increases the minute volume; decreasing the rate decreases the minute volume.
  18. How is the PaCO2 most effectively controlled on PT's using controlled ventilation or SIMV? Why?
    On controlled or SIMV PaCO2 is most effectively controlled by altering the rate. Because the Patient's RR is dependent and controlled by the vent. So changing the rate changes the PaCO2
  19. What is the most effective way to control PaCO2 when the PT is on Assist/control? Why?
    When on Assist/control the pt may obtain as many breaths as needed no matter the rate so the most effective way to adjust PaCO2 is by adjusting TV
  20. What is the normal setting for Inspiratory flow control?
    40-60 L/min
  21. How does adjusting the flow rate alter the I:E ratio?
    • It alters the Inspiratory time
    • increasing flow rate decreases I time
    • decreasing flow rate increases I time
  22. How do you alter the Inspiratory time and the Expiratory time on the I:E ratio
    • Altering the flow adjusts the inspiratory time
    • Altering the rate adjusts the expiratory time
    • Altering the VT adjusts the inspiratory time
  23. What are the 2 ways to control PaCO2?
    adjusting TV or Flow rate
  24. What portion of the I:E ratio controls PaCO2?
  25. What is the difference between adjusting flow rate and Tidal Volume
    The flow rate is how fast air gets to lungs tidal volume is the amount that the lungs receive
  26. How does altering the TV change alter the I:E ratio
    • increasing TV increases I time (makes longer)
    • decreasing TV decreases I time (makes shorter)
  27. What are the parameters for the sensitivity control?
    -0.5 to -2.0
Card Set
per chap 11