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Regional respiratory inflation and deflation pressure-volume curves determined by electrical impedance tomography
journal contribution
posted on 2023-05-17, 21:10 authored by Frerichs, I, Peter DargavillePeter Dargaville, Rimensberger, PCMeasurement of regional lung volume changes during a quasi-static pressure-volume (PV) manoeuvre using electrical impedance tomography (EIT) could be used to assess regional respiratory system mechanics and to determine optimal ventilator settings in individual patients. Using this approach, we studied regional respiratory system mechanics in healthy and lung-injured animals, before and after surfactant administration during inflation and deflation PV manoeuvres. The comparison of the EIT-derived regional PV curves in ventral, middle and dorsal regions of the right and left lungs showed not only different amounts of hysteresis in these regions but also marked differences among different landmark pressures calculated on the inflation and deflation limbs of the curves. Regional pressures at maximum compliance as well as the lower and upper pressures of maximum compliance change differed between the inflation and deflation and increased from ventral to dorsal regions in all lung conditions. All these pressure values increased in the injured and decreased in the surfactant treated lungs. Examination of regional respiratory system mechanics using EIT enables the assessment of spatial and temporal heterogeneities in the ventilation distribution. Characteristic landmarks on the inflation and especially on the deflation limb of regional PV curves may become useful measures for guiding mechanical ventilation.
History
Publication title
Physiological MeasurementVolume
34Issue
6Pagination
567-577ISSN
0967-3334Department/School
Menzies Institute for Medical ResearchPublisher
IOP Publishing LtdPlace of publication
Dirac House, Temple Back, Bristol, England, Bs1 6BeRights statement
Copyright 2013 Institute of Physics and Engineering in MedicineRepository Status
- Restricted