Lung Function during Intensive Care

Coordinator: Gaetano Perchiazzi, Associate Professor at the Department of Surgical Sciences, Anaesthesiology and Intensive Care, e-mail:

Our research field is artificial ventilation and respiratory mechanics of intensive care patients. We have two main areas of investigation, both active.

- The first regards the use of technologies of artificial intelligence to extract parameters of respiratory mechanics at the airway opening of ventilated patients. Per se, this research brings to developing instruments to continuously monitor patients in a more robust way than conventional bedside equipment.

- The second area of investigation exploits the use of mathematical analysis of imaging technologies. The purpose is to study the micromechanics of lung and its role in the generation of lung injury during mechanical ventilation.

The group is formed by medical doctors trained in the use of advanced methods of mathematical analysis of images and signals who cooperate with biologists, physicists, engineers.

The knowledge of MatLab image processing and signal analysis toolboxes allows us to combine information deriving from medical imaging with more “classical” spirometry measurements, in order to obtain a complete new set of physiological information from the lung. An example is the application of these technologies to the diaphragm function during spontaneous breathing, a very important clinical issue in intensive care medicine.

Our Contribution to Medical Research


We have been among the very first to apply technologies of artificial intelligence to extract quantitative information from respiratory tracings derived from mechanically ventilated subjects. This research paved the way to the development of monitoring tools now incorporated in intensive care monitors.

  • Assessment of respiratory system mechanics by artificial neural networks: an exploratory study. Perchiazzi G, Högman M, Rylander C, Giuliani R, Fiore T, Hedenstierna G. J Appl Physiol (1985). 2001 May;90(5):1817-24. doi:10.1152/jappl.2001.90.5.1817.
  • Estimating respiratory system compliance during mechanical ventilation using artificial neural networks. Perchiazzi G, Giuliani R, Ruggiero L, Fiore T, Hedenstierna G. Anesth Analg. 2003 Oct;97(4):1143-8 doi: 10.1213/01.ane.0000077905.92474.82.

This research is now pointing at developing tools for controlling mechanical ventilation in closed loop teamed up with engineers of the Department of Electrical Engineering of Uppsala University (with Ass. Prof. Robin Augustine and Researcher Mauricio Perez).


We have developed methods for computing and assigning lung mechanical parameters (as compliance) voxel-by-voxel to lung computed tomography, drawing the field of elastic forces acting on the lung. This method of study gave new insight to the knowledge of lung inhomogeneity during mechanical ventilation.

  • Regional distribution of lung compliance by image analysis of computed tomograms. Perchiazzi G, Rylander C, Derosa S, Pellegrini M, Pitagora L, Polieri D, Vena A, Tannoia A, Fiore T, Hedenstierna G. Respir Physiol Neurobiol. 2014 Sep 15;201:60-70. doi: 10.1016/j.resp.2014.07.001.
  • Effects of superimposed tissue weight on regional compliance of injured lungs. Pellegrini M, Derosa S, Tannoia A, Rylander C, Fiore T, Larsson A, Hedenstierna G, Perchiazzi G. Respir Physiol Neurobiol. 2016 Jul;228:16-24. doi: 10.1016/j.resp.2016.03.005.

We actively collaborate with the Translational Positron Emission Tomography Imaging lab (Ass. Prof. Olof Eriksson) in projects aiming at combining information about lung inflammation and the topographical distribution of lung properties. 


Together with the researchers from the European Synchrotron Radiation Facility and the MAX IV synchrotron in Lund we are among the few that can look at the lung at ultra high resolution, in vivo, during mechanical ventilation using synchrotron radiation computed tomography. These observations guided us to propose new theories about the process of lung inflation and about lung inhomogeneity during mechanical ventilation.

  • Regional Behavior of Airspaces During Positive Pressure Reduction Assessed by Synchrotron Radiation Computed Tomography. Scaramuzzo G, Broche L, Pellegrini M, Porra L, Derosa S, Tannoia AP, Marzullo A, Borges JB, Bayat S, Bravin A, Larsson A, Perchiazzi G. Front Physiol. 2019 Jun 7;10:719. doi: 10.3389/fphys.2019.00719. eCollection 2019.
  • Dynamic Mechanical Interactions Between Neighboring Airspaces Determine Cyclic Opening and Closure in Injured Lung. Broche L, Perchiazzi G, Porra L, Tannoia A, Pellegrini M, Derosa S, Sindaco A, Batista Borges J, Degrugilliers L, Larsson A, Hedenstierna G, Wexler AS, Bravin A, Verbanck S, Smith BJ, Bates JH, Bayat S. Crit Care Med. 2017 Apr;45(4):687-694. doi: 10.1097/CCM.0000000000002234.


By using our own developed programs we are able to synchronize computer tomography imaging, spirometry and electrical activity of the diaphragm. By this way, we have created a new standard in the assessment of lung physiology during spontaneous and assisted ventilation.

  • The Diaphragm Acts as a Brake during Expiration to Prevent Lung Collapse. Pellegrini M, Hedenstierna G, Roneus A, Segelsjö M, Larsson A, Perchiazzi G. Am J Respir Crit Care Med. 2017 Jun 15;195(12):1608-1616. doi: 10.1164/rccm.201605-0992OC.
  • Expiratory Resistances Prevent Expiratory Diaphragm Contraction, Flow Limitation, and Lung Collapse. Pellegrini M, Gudmundsson M, Bencze R, Segelsjö M, Freden F, Rylander C, Hedenstierna G, Larsson AS, Perchiazzi G. Am J Respir Crit Care Med. 2020 May 15;201(10):1218-1229. doi: 10.1164/rccm.201909-1690OC.

Our research is currently supported by grants from the following sources:

  • The European Society of Intensive Care Medicine
  • The Swedish Heart and Lung foundation
  • The Swedish Research Council
  • The ALF grant from the Swedish State
  • The Allvar Gullstrand grant

Our base is the Hedenstierna Laboratory at Uppsala University which is equipped with state of the art technologies, including monitors, ventilators, dialysis machines, infusion pumps, data acquisition systems.

It is organized as an intensive care unit, able to perform simultaneous measurements up to seven stations simultaneously. The laboratory has several high specialized research assistants / medical technicians.

With us it is possible to develop projects of different complexity, from the undergraduate level to post-doctoral research.

If you want to join our research group, please send an e-mail to Eva-Maria Hedin Specify what you are interested in and which type of project you want to develop (PhD thesis, ST-project, student project, international collaboration, research visit).

Members of the research group 2021

Perchiazzi, Gaetano, MD, specialist, PhD, Associate Professor
Hedin, Eva-Maria, Research assistant

Senior Researchers
Hedenstierna, Göran MD, specialist, PhD, Senior Professor
Fredén, Filip, MD, specialist, PhD, Associate Professor
Frykholm, Peter, MD, specialist, PhD, Associate Professor
Larsson Anders, MD, specialist, PhD, Senior Professor
Olivero-Reinius, Henrik, MD, specialist, PhD, Director of Specialty Program
Pellegrini, Mariangela, MD, specialist, PhD, MD, Post-Doc

Barrueta, Annelie, MD, spec. in training, PhD student
Bencze, Reka, MD, specialist
Bergmann, Astrid, MD, specialist, PhD
Bjarnadottir, Kristin Jona, MD, spec. in training
Blokhin, Ivan, MD, specialist
Chiodaroli, Elena, MD, specialist
Dirscherl, Konstantin, MD, specialist
Engström, Joakim, Specialist SSK, PhD
Larina, Aleksandra, MD, spec. in training
Liggieri, Francesco, MD, spec. in training
Maltese, Antonio, MD, spec. in training
Mariotti, Paola Sara, MD, spec. in training
Pedrotti, Niccolò, MD, spec. in training
Ravlic, Martina, MD, spec. in training
Scaramuzzo, Gaetano, MD, specialist
Widing, Hannes, MD, spec. in training, PhD student

A list of the publications produced in the last five years from the research groups working at the Hedenstierna Laboratory (research themes: respiration, sepsis, kidney, cardiac arrest and hemodynamics) can be read by clicking this PubMed link.

Gaetano Perchiazzi

Researcher Associate Professor at Department of Surgical Sciences, Anaesthesiology and Intensive Care

Mobile phone:
+46 70 5640861
Last modified: 2021-05-18