Lung water assessment: from gravimetry to wearables

  • Frederic MichardEmail author


Several techniques are now available to detect and quantify pulmonary edema, from the laboratory postmortem method (gravimetry) to non-invasive wearable sensors. In critically ill patients with adult respiratory distress syndrome (ARDS), computed tomography scans are often performed to visualize lung lesions and quantify lung aeration, but their value seems somewhat limited to quantify pulmonary edema on a routine basis and of course to track changes with therapy. In this context, transpulmonary thermodilution is a convenient technique. It is invasive but most patients with ARDS have a central line and an arterial catheter in place. In addition to extravascular lung water measurements, transpulmonary thermodilution enables the measurement of hemodynamic variables that are useful to guide fluid and diuretic therapy. Echo probes are about to replace the stethoscope in our pocket and, if B lines (aka comet tails) do not allow a real quantification of pulmonary edema, they are useful to detect an increase in lung water. Finally, wireless and wearable sensors are now available to monitor patients on hospital wards and beyond (home monitoring). They should enable the detection of pulmonary congestion at a very early stage, and if combined with a proactive therapeutic strategy, have potential to improve outcome.


Pulmonary edema Lung water Transpulmonary thermodilution Point of care ultrasound Wearable 


Compliance with ethical standards

Conflict of interest

FM is the founder and managing director of MiCo, a Swiss consulting firm. MiCo does not sale any medical product. FM does not own shares and does not receive royalties from any medtech company.


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Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.MiCoDenensSwitzerland

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