1 / 26

Basic Pulmonary Mechanics during Mechanical Ventilation

Basic Pulmonary Mechanics during Mechanical Ventilation. Equation of Motion. dP = R x Flow + dV / C st. Points of Discussion. Equation of motion Airway pressures Compliance Resistance Pressure-Time Flow-Time Pressure-volume loop Flow-volume loop. Spontaneous Breathing.

step
Download Presentation

Basic Pulmonary Mechanics during Mechanical Ventilation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Basic Pulmonary Mechanics during Mechanical Ventilation Equation of Motion dP=Rx Flow +dV / C st

  2. Points of Discussion • Equation of motion • Airway pressures • Compliance • Resistance • Pressure-Time • Flow-Time • Pressure-volume loop • Flow-volume loop

  3. Spontaneous Breathing Exhalation Inspiration

  4. Precondition of Inspiration Gas Flow Pa • Pa<Pb • Spontaneous breath • Pb>Pa • Mechanical ventilation Pb

  5. Lung Mechanics transairway pressure transrespiratory pressure transthoracic pressure volume compliance= Dvolume/ Dpressure resistance = Dpressure / Dflow flow

  6. Tube + Spring Model Resistive Forces Elastic Forces

  7. Airway Resistance “The Feature of the Tube” D P R = D F Pressure Difference= Flow Rate x Resistance

  8. Compliance Volume D V D P Pressure D V Cs= D P Pressure Difference = Volume Change/ Compliance

  9. Compliance and Resistance D P R = D F D V Cs= D P

  10. Equation of Motion DYNAMIC CHARACTERISTICS: dP = dV / Cdyn RESISTANCE: dPresistive= R x Flow STATIC COMPLIANCE: dPdistensive = dV / Cst dP = dPresist. + dP dist. dP = R x Flow + dV / C st

  11. Equation of Motion dP=Rx Flow +dV / C st

  12. Components of Inflation Pressure Pplateau (Palveolar) Begin Inspiration PIP } Transairway Pressure (PTA) Paw (cm H2O) Inspiratory Pause Expiration Time (sec) Begin Expiration

  13. Exhalation Valve Opens Begin Inspiration Inflation Hold (seconds) Pplateau (Palveolar Paw (cm H2O) Time (sec) PIP } Transairway Pressure (PTA) Paw (cm H2O) Expiration Time (sec) Begin Expiration PIP Distending (Alveolar) Pressure Airway Resistance Expiration Begin Inspiration Begin Expiration

  14. Spontaneous vs. Mechanical Mechanical Inspiration Paw (cm H2O) Spontaneous Expiration Expiration Inspiration Time (sec)

  15. PIP vsPplat PIP PIP PPlat High Raw PPlat Normal Paw (cm H2O) PIP PIP PPlat High Flow Low Compliance PPlat Time (sec)

  16. Mean Airway Pressure Lengthen Inspiratory Time Increase peak pressure Increase PEEP Increase Rate Increase Flow

  17. Inspiratory Flow Pattern Total cycle time TCT Peak Expiratory Flow Rate PEFR Beginning of expiration exhalation valve opens Peak inspiratory flow rate PIFR Inspiration Inspiratory Time TI Expiratory Time TE Flow (L/min) Time (sec) Beginning of inspiration exhalation valve closes Expiration

  18. Flow vs Time Inspiration Time (sec) Flow (L/min) Expiration

  19. Flow Patterns SQUARE DECELERATING ACCELERATING SINE

  20. Flow Patterns and Effects of Volume ACCELERATING SINE DECELERATING SQUARE

  21. Mechanical vs Spontaneous Mechanical Spontaneous Inspiration Expiration

  22. Volume vs. Time Inspiratory Tidal Volume Volume (ml) Inspiration Expiration TI Time (sec)

  23. FRC and PV Loop Normal Compliance TLC VOLUME FRC FRC Negative Positive 0 DISTENDING PRESSURE

  24. Components of Pressure-Volume Loop VT Expiration Volume (mL) Inspiration PIP Paw (cm H2O)

  25. PEEP and P-V Loop VT PEEP PIP Volume (mL) Paw (cm H2O)

  26. Thank You

More Related