Authors: Aleš Rára, Karel Roubík, Tomáš Tyll


Rara, A., Roubik, K., Tyll, T. Effects of pleural effusion drainage in the mechanically ventilated patient as monitored by electrical impedance tomography and end-expiratory lung volume: A pilot study. Journal of Critical Care, 59, October 2020, pp. 76-80.

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Published in Journal of Critical Care, 2020


Purpose: In patients with pleural effusion (PLE) monitored by Electrical Impedance Tomography (EIT) an increase in end-expiratory lung impedance (EELI) is observed following evacuation of the PLE. We aimed at differentiating the effect of fluid removal from lung reaeration and describe the change in ventilation distribution.
Materials and methods: Mechanically ventilated patients were monitored by EIT during PLE evacuation. End-expiratory lung volume (EELV) was measured concurrently. We included a calibration maneuver consisting of an increase in positive end-expiratory pressure (PEEP) by 5 cm H2O. The ratio ΔEELI/ΔEELV was used to compare changes of EELI and EELV in response to the calibration maneuver and PLE evacuation. At the same time we assessed distribution of ventilation using changes in tidal variation.
Results: PLE removal resulted in a 6–fold greater increase in ΔEELI/ΔEELV when compared to the calibration maneuver (r = 0.84, p < .05). We observed a relative increase in ventilation in the area of the effusion (mean 7.1%, p < .006) and an overall shift of ventilation to the dorsal fraction of the lungs (mean 8%, p < .0002).
Conclusions: The increase in EELI in the EIT image after PLE removal was primarily due to the removal of the conductive effusion fluid.


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