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Combining Volumetric Capnography And Barometric Plethysmography To Measure The Lung Structure-function Relationship
Published on: January 8, 2019
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Multivariate analysis of the volumetric capnograph for PaCO2 estimation
Slava M Belenkiy1, William L Baker1, Andriy I Batchinsky2
1U.S. Army Institute of Surgical Research USA.
International Journal of Burns and Trauma
|November 10, 2015
Summary
Estimating arterial CO2 (PaCO2) is challenging during instability. New multivariate methods using volumetric capnograph (Vcap) waveforms modestly improved PaCO2 estimation accuracy in a porcine model.
Area of Science:
- Anesthesiology
- Critical Care Medicine
- Respiratory Physiology
Background:
- End-tidal CO2 (eTCO2) estimates arterial CO2 (PaCO2) under stable conditions.
- This estimation accuracy declines during hemodynamic or respiratory instability.
Purpose of the Study:
- To develop and test a multivariate method for improved PaCO2 estimation.
- Utilize volumetric capnograph (Vcap) waveform features beyond eTCO2.
Main Methods:
- A porcine model with induced chest trauma and hemorrhage was used.
- Data analyzed using multivariate linear regression and M5P machine-learning models.
- Vcap features including eTCO2, phase 2 slope, phase 3 slope, and inter-breath interval were measured.
Main Results:
- Univariate eTCO2 models were adequate only during stable conditions.
- Multivariate models incorporating Vcap features significantly improved PaCO2 estimation accuracy during instability.
- M5P model with Vcap features reduced mean error to -1.62 mmHg (R(2)=0.25).
Conclusions:
- Multivariate methods incorporating Vcap waveform features offer modest improvements in PaCO2 estimation.
- These methods show particular benefit during hemodynamic and respiratory instability.
- Further research is needed for a clinically applicable CO2 monitoring system.
Keywords:
End-tidal carbon dioxidearterial carbon dioxidecapnographyhemorrhagemachine learningpulmonary contusionMore Related Videos
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