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Intensive Care Medicine

, Volume 29, Issue 12, pp 2312–2316 | Cite as

Electrical impedance tomography: a method for monitoring regional lung aeration and tidal volume distribution?

  • Inéz Frerichs
  • Peter A. Dargaville
  • Taras Dudykevych
  • Peter C. Rimensberger
Brief Report

Abstract

Objective

To demonstrate the monitoring capacity of modern electrical impedance tomography (EIT) as an indicator of regional lung aeration and tidal volume distribution.

Design and setting

Short-term ventilation experiment in an animal research laboratory.

Patients and participants

One newborn piglet (body weight: 2 kg).

Interventions

Surfactant depletion by repeated bronchoalveolar lavage, surfactant administration.

Measurements and results

EIT scanning was performed at an acquisition rate of 13 images/s during two ventilatory manoeuvres performed before and after surfactant administration. During the scanning periods of 120 s the piglet was ventilated with a tidal volume of 10 ml/kg at positive end-expiratory pressures (PEEP) in the range of 0–30 cmH2O, increasing and decreasing in 5 cmH2O steps. Local changes in aeration and ventilation with PEEP were visualised by EIT scans showing the regional shifts in end-expiratory lung volume and distribution of tidal volume, respectively. In selected regions of interest EIT clearly identified the changes in local aeration and tidal volume distribution over time and after surfactant treatment as well as the differences between stepwise inflation and deflation.

Conclusions

Our data indicate that modern EIT devices provide an assessment of regional lung aeration and tidal volume and allow evaluation of immediate effects of a change in ventilation or other therapeutic intervention. Future use of EIT in a clinical setting is expected to optimise the selection of appropriate ventilation strategies.

Keywords

Electrical impedance tomography Impedance Ventilation distribution Ventilation monitoring Saline lavage 

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Copyright information

© Springer-Verlag 2003

Authors and Affiliations

  • Inéz Frerichs
    • 1
  • Peter A. Dargaville
    • 2
  • Taras Dudykevych
    • 1
  • Peter C. Rimensberger
    • 3
  1. 1.Department of Anaesthesiological Research, Centre of Anaesthesiology, Emergency and Intensive Care MedicineUniversity of GöttingenGöttingenGermany
  2. 2.Department of NeonatologyRoyal Children’s HospitalMelbourneAustralia
  3. 3.Paediatric and Neonatal Intensive Care Unit, Hôpital des EnfantsUniversity Hospital of GenevaGenevaSwitzerland

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