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Updated: May 26, 2026
10:02
Characterization of the Isolated, Ventilated, and Instrumented Mouse Lung Perfused with Pulsatile Flow
Published on: April 29, 2011
The flow-time waveform predicts respiratory system resistance and compliance
Boulos S Nassar1, Nicole D Collett, Gregory A Schmidt
1Division of Pulmonary, Critical Care, and Occupational Medicine, Department of Internal Medicine, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA. boulos-nassar@uiowa.edu
Journal of Critical Care
|January 10, 2012
Summary
Lung compliance and resistance can be estimated during pressure assist-control ventilation (PACV), correlating well with values from volume assist-control ventilation (VACV). This finding aids clinical management of mechanically ventilated patients.
Area of Science:
- Respiratory Mechanics
- Mechanical Ventilation
Background:
- Accurate assessment of lung compliance and resistance is crucial for effective clinical management of mechanically ventilated patients.
- These parameters are routinely measured during volume assist-control ventilation (VACV).
Purpose of the Study:
- To investigate if lung compliance and resistance can be reliably estimated during pressure assist-control ventilation (PACV).
- To compare these estimations with values obtained during VACV.
Main Methods:
- Collected data from 12 mechanically ventilated human subjects.
- Measured respiratory parameters during both VACV and PACV modes.
- Calculated inspiratory resistance and compliance during PACV by extrapolating the linear component of the pressure-time waveform.
Main Results:
- Mean compliance during PACV (37.06 ± 15.65 mL/cm H2O) closely matched VACV values (36.93 ± 12.18 mL/cm H2O).
- Mean inspiratory resistance during PACV (15.17 ± 5.14 cm H2O/L/s) showed strong correlation with VACV values (12.50 ± 2.99 cm H2O/L/s), with R² of 0.73 and 0.51 respectively.
- A strong correlation was observed between compliance and inspiratory resistance calculated during PACV versus VACV.
Conclusions:
- The inspiratory flow waveform during PACV is linear and contains information about respiratory system resistance and compliance.
- Estimated lung compliance and resistance during PACV correlate well with conventionally measured values during VACV.
- These findings support the use of PACV for estimating key respiratory mechanics parameters.
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