Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Low-frequency respiratory mechanics using ventilator-driven forced oscillations

K R Lutchen1, D W Kaczka, B Suki

  • 1Department of Biomedical Engineering, Boston University, Massachusetts 02215.

Journal of Applied Physiology (Bethesda, Md. : 1985)
|December 1, 1993
PubMed
Summary
This summary is machine-generated.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Day-to-Day Variability of Respiratory Resistance in Asthma and COPD: Influence of Intra-Breath Data Sampling and Observation Period.

IEEE journal of translational engineering in health and medicine·2026
Same author

Wind of change: Better air for microbial environmental control.

Case studies in chemical and environmental engineering·2023
Same author

Safer school with near-UV technology: novel applications for environmental hygiene.

Journal of environmental health science & engineering·2023
Same author

Disinfecting Slush Machines by an Innovative Near Ultraviolet Light Emitting Diode (UV LED) Technological System.

Annali di igiene : medicina preventiva e di comunita·2022
Same author

EBV persistence in gastric cancer cases conventionally classified as EBER-ISH negative.

Infectious agents and cancer·2022
Same author

Improvement and standardization of disinfection in hospital theatre with ultraviolet-C technology.

The Journal of hospital infection·2022

Fast Fourier Transform (FFT) analysis of ventilator waveforms can estimate respiratory impedance. However, signal energy in humans is limited, unlike in dogs, impacting impedance spectra quality.

Area of Science:

  • Respiratory mechanics
  • Pulmonary physiology
  • Signal processing

Background:

  • Estimating respiratory impedance (resistance and elastance) is crucial for mechanical ventilation.
  • Frequency dependence of respiratory system mechanics provides insights into lung and chest wall properties.
  • Standard ventilator waveforms may offer a non-invasive method for impedance assessment.

Purpose of the Study:

  • To evaluate the feasibility of using Fast Fourier Transform (FFT) analysis on standard ventilator waveforms to estimate frequency dependence of respiratory impedance.
  • To compare impedance estimates derived from sine wave forcing versus a step ventilator flow wave in humans and animals.
  • To investigate factors influencing the quality and reliability of impedance spectra obtained from ventilator data.

Main Methods:

Related Experiment Videos

  • Healthy humans and mechanically ventilated patients underwent measurements of airway pressure and flow.
  • Sine wave forcing (0.2–0.6 Hz) and a step inspiratory ventilator flow wave were applied at varying tidal volumes.
  • Dogs with induced pulmonary edema were studied using simultaneous respiratory, lung, and chest wall impedance measurements (0.156–2 Hz).
  • FFT analysis was applied to waveform data to estimate respiratory resistance (Rrs) and elastance (Ers).

Main Results:

  • Humans showed minimal frequency dependence of Rrs and Ers below 0.6 Hz, with higher tidal volumes decreasing these values.
  • Step waveform spectral estimates in humans were comparable to sine wave results below 0.6 Hz but became erratic at higher frequencies.
  • In dogs, step wave analysis provided reliable impedance estimates up to 2 Hz, revealing oscillations related to nonlinear chest wall processes.
  • Ventilator flow signal energy in humans was insufficient beyond the third harmonic, influenced by the expiratory time constant, unlike in dogs.

Conclusions:

  • FFT analysis of standard ventilator waveforms can estimate respiratory impedance, but signal quality is subject-dependent.
  • Nonlinear chest wall mechanics can cause oscillations in impedance estimates, particularly in animal models.
  • The frequency content of ventilator flow is crucial for obtaining reliable impedance spectra, with limitations observed in human subjects.
  • Further research is needed to optimize ventilator-derived impedance measurements for clinical application.