Acute Hypoxemic Respiratory FailureTAC-EIT-20-5NCT07175194
Association Between EIT and CT During PEEP Titration in Patients With Acute Respiratory Failure
An observational study of Acute Hypoxemic Respiratory Failure and Ventilation, Mechanical, run by Istituto Clinico Humanitas at 1 site in Italy.
Trial summary
This observational study will analyze data already collected by the investigators as part of their routine clinical practice from patients with acute respiratory failure (ARF) treated with mechanical ventilation. The study itself does not require any specific intervention. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Acute Hypoxemic Respiratory Failure, Ventilation, Mechanical
- How many people
- 30 participants
- Where
- 1 siteItaly
- Study dates
- 1 Nov 2025to Jun 2027
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adults admitted to the Intensive Care Unit of the IRCCS Humanitas Research Hospital, in Rozzano (Milan, Italy), with acute respiratory failure treated with mechanical ventilation
Who may be able to join
- Adults (≥18 years of age) admitted to our Unit with ARF treated with mechanical ventilation
- The patient undergoes a lung CT and EIT to guide the setting of PEEP as part of our routine clinical practice
Who cannot join
- The patient cannot undergo a lung CT and/or EIT as judged by the attending physician (for instance, transport to the radiology unit may be considered too risky if the patient is extremely severe, or using EIT may be contraindicated because of the presence of a pacemaker)
- Pregnancy (as this condition alters the respiratory physiology)
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Italy1 site, 1 recruiting
- Recruiting
IRCCS Humanitas Research Hospital
Milan, Milan, 20089
Alessandro Protti, +39.02.82244135, alessandro.protti@hunimed.eu
About this study
Official title: Association Between the "Best" Positive End-Expiratory Pressure Identified With Electrical Impedance Tomography and the Potential for Hyperinflation and Collapse Assessed With Lung Computed Tomography in Mechanically Ventilated Patients With Acute Respiratory Failure
This observational study will analyze data already collected by the investigators as part of their routine clinical practice from patients with acute respiratory failure (ARF) treated with mechanical ventilation. The study itself does not require any specific intervention.
Mechanical ventilation can save the lives of patients with ARF. However, if used improperly, it can exacerbate lung disease and worsen outcomes (Slutsky et al.).
Read more
Despite decades of animal and clinical research, it remains unclear how to establish the positive end-expiratory pressure (PEEP) during mechanical ventilation to reduce the risk of lung damage. Several methods have been suggested, but none have consistently proven superior to the others (Sahetya et al.).
As part of their routine clinical practice, the investigators study the responses to different PEEP levels of patients with ARF undergoing mechanical ventilation by integrating information from various techniques, each examining different aspects of lung morphology and physiology. The methods the investigators use include lung computed tomography (CT) and electrical impedance tomography (EIT). Lung CT is the reference technique for measuring the morphological response to PEEP (Gattinoni et al.). It quantifies the volume of the hyperinflated and non-aerated lung, both of which are related to the risk of mechanical ventilation causing damage (Slutsky et al.). Lung EIT monitors the functional response to PEEP in terms of changes in regional compliance across different PEEP levels. Allegedly, an increase in compliance when PEEP is decreased reveals overdistention, the functional correlate of (worrisome) hyperinflation, at the higher PEEP. A decrease in compliance when PEEP is decreased signals new collapse, the functional correlate of (worrisome) loss of aeration (Franchineau et al.).
In the Unit where the investigators work, patients with ARF treated with mechanical ventilation are routinely studied as follows. First, a lung CT with a PEEP of 20 cmH2O and then of 5 cmH2O is obtained. Thereafter, a decremental PEEP test is performed with the EIT, where PEEP is decreased from 20 cmH2O down to 5 cmH2O in steps of 2 or 3 cmH2O. Finally, results are analyzed and compared offline.
At the lung CT, decreasing PEEP from 20 to 5 cmH2O is always associated with some decrease in the volume of the hyperinflated lung and some increase in the volume of the non-aerated lung. However, the magnitude of these two effects varies among individuals, and the net response may be defined as the difference between those two competing effects. If the decrease in the volume of the hyperinflated lung is greater than the increase in the volume of the non-aerated lung, the overall response (i.e., less hyperinflation) can be considered positive. PEEP should then be set closer to 5 than to 20 cmH2O. Diversely, if the decrease in the volume of the hyperinflated lung is smaller than the increase in the volume of the non-aerated lung, the overall response (i.e., more loss of aeration) can be considered negative. PEEP should then be set closer to 20 cmH2O (Protti et al.). Similarly, at the lung EIT, decreasing PEEP from 20 to 5 cmH2O is always associated with compliance improvement in some regions (i.e., less overdistension) and worsening in others (i.e., more collapse). Again, the magnitude of these two opposite effects varies among individuals. According to most experts on lung EIT, PEEP should be set at the level where both overdistension and collapse are minimized (the so-called "best" PEEP) (Jonkman et al.).
Lung CT requires transfer to the radiology unit, exposure of the patient to radiation, and complex analysis offline. By contrast, lung EIT is virtually risk-free, and analysis can be performed using an automatic algorithm. Nevertheless, lung EIT is less well validated than lung CT. For instance, the assumption that a decrease in compliance in response to a decrease in PEEP is due to new collapse has been questioned (Protti et al., Chiumello et al., Menga et al.). So far, lung CT remains the reference technique for studying individual responses to PEEP, while lung EIT requires further validation.
This study aims to verify whether the "best" PEEP identified using lung EIT is strongly associated with the net response assessed using lung CT, when PEEP is decreased from 20 to 5 cmH2O in patients with ARF treated with mechanical ventilation. If so, this would strengthen the rationale for using the lung EIT (which is safer and simpler than the lung CT) to set PEEP.
- Keywords
- Positive End-Expiratory Pressure, Computed Tomography, Electrical Impedance Tomography
- Medical subject headings
- Respiratory Insufficiency, Respiratory Aspiration
What is being measured
The primary outcome is the main question the study is designed to answer.
Association Between Lung EIT and CT Findings During PEEP Titration
The investigators will use the Spearman's correlation coefficient (rho) to measure the strength of the linear association between these two continuous variables:
Y: the "best" PEEP identified with the EIT, as the PEEP level between 20 and 5 cmH2O where overdistension and collapse are minimal. This variable is measured in cmH2O.
X: the overall net response to decreasing PEEP from 20 to 5 cmH2O, as assessed with the lung CT. This variable is the difference between the decrease in the volume of the hyperinflated lung and the increase in the volume of the non-aerated lung across the two PEEP levels and is measured in ml.
Measured: Within 72 hours from the start of mechanical ventilation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted16 Sep 2025
- Study start1 Nov 2025
- Primary completionMar 2027 (estimated)
- Study completionJun 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (8)Papers the sponsor has linked to this study.
- Other trials for Acute Hypoxemic Respiratory FailureStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Istituto Clinico Humanitas
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07175194
- Sponsor's protocol ID
- TAC-EIT-20-5
- Acronym
- TAC-EIT-20-5
- Status last verified
- May 2026
- First submitted
- 9 Sep 2025
- Last updated
- 19 May 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Publications
Slutsky AS, Ranieri VM. Ventilator-induced lung injury. N Engl J Med. 2013 Nov 28;369(22):2126-36. doi: 10.1056/NEJMra1208707. No abstract available.
PubMed 24283226Sahetya SK, Goligher EC, Brower RG. Fifty Years of Research in ARDS. Setting Positive End-Expiratory Pressure in Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2017 Jun 1;195(11):1429-1438. doi: 10.1164/rccm.201610-2035CI.
PubMed 28146639Gattinoni L, Caironi P, Cressoni M, Chiumello D, Ranieri VM, Quintel M, Russo S, Patroniti N, Cornejo R, Bugedo G. Lung recruitment in patients with the acute respiratory distress syndrome. N Engl J Med. 2006 Apr 27;354(17):1775-86. doi: 10.1056/NEJMoa052052.
PubMed 16641394Franchineau G, Jonkman AH, Piquilloud L, Yoshida T, Costa E, Roze H, Camporota L, Piraino T, Spinelli E, Combes A, Alcala GC, Amato M, Mauri T, Frerichs I, Brochard LJ, Schmidt M. Electrical Impedance Tomography to Monitor Hypoxemic Respiratory Failure. Am J Respir Crit Care Med. 2024 Mar 15;209(6):670-682. doi: 10.1164/rccm.202306-1118CI.
PubMed 38127779Protti A, Santini A, Pennati F, Chiurazzi C, Cressoni M, Ferrari M, Iapichino GE, Carenzo L, Lanza E, Picardo G, Caironi P, Aliverti A, Cecconi M. Lung Response to a Higher Positive End-Expiratory Pressure in Mechanically Ventilated Patients With COVID-19. Chest. 2022 Apr;161(4):979-988. doi: 10.1016/j.chest.2021.10.012. Epub 2021 Oct 16.
PubMed 34666011Jonkman AH, Alcala GC, Pavlovsky B, Roca O, Spadaro S, Scaramuzzo G, Chen L, Dianti J, Sousa MLA, Sklar MC, Piraino T, Ge H, Chen GQ, Zhou JX, Li J, Goligher EC, Costa E, Mancebo J, Mauri T, Amato M, Brochard LJ; Pleural Pressure Working Group (PLUG). Lung Recruitment Assessed by Electrical Impedance Tomography (RECRUIT): A Multicenter Study of COVID-19 Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2023 Jul 1;208(1):25-38. doi: 10.1164/rccm.202212-2300OC.
PubMed 37097986Chiumello D, Marino A, Brioni M, Cigada I, Menga F, Colombo A, Crimella F, Algieri I, Cressoni M, Carlesso E, Gattinoni L. Lung Recruitment Assessed by Respiratory Mechanics and Computed Tomography in Patients with Acute Respiratory Distress Syndrome. What Is the Relationship? Am J Respir Crit Care Med. 2016 Jun 1;193(11):1254-63. doi: 10.1164/rccm.201507-1413OC.
PubMed 26699672Menga LS, Subira C, Wong A, Sousa M, Brochard LJ. Setting positive end-expiratory pressure: does the 'best compliance' concept really work? Curr Opin Crit Care. 2024 Feb 1;30(1):20-27. doi: 10.1097/MCC.0000000000001121. Epub 2023 Nov 29.
PubMed 38085857
Study at a glance
From the registry record, last updated by the sponsor on 19 May 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Association Between the "Best" Positive End-Expiratory Pressure Identified With Electrical Impedance Tomography and the Potential for Hyperinflation and Collapse Assessed With Lung Computed Tomography in Mechanically Ventilated Patients With Acute Respiratory Failure
- ClinicalTrials.gov ID
- NCT07175194
- Acronym / sponsor ID
- TAC-EIT-20-5 / TAC-EIT-20-5
- Keywords
- Positive End-Expiratory Pressure, Computed Tomography, Electrical Impedance Tomography
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Istituto Clinico HumanitasUniversity, hospital or other
- Study start
- 1 Nov 2025 (actual)
- Primary completion
- Mar 2027 (estimated)
- Study completion
- Jun 2027 (estimated)
- First posted
- 16 Sep 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This observational study will analyze data already collected by the investigators as part of their routine clinical practice from patients with acute respiratory failure (ARF) treated with mechanical ventilation. The study itself does not require any specific intervention.
Mechanical ventilation can save the lives of patients with ARF. However, if used improperly, it can exacerbate lung disease and worsen outcomes (Slutsky et al.).
Despite decades of animal and clinical research, it remains unclear how to establish the positive end-expiratory pressure (PEEP) during mechanical ventilation to reduce the risk of lung damage. Several methods have been suggested, but none have consistently proven superior to the others (Sahetya et al.).
As part of their routine clinical practice, the investigators study the responses to different PEEP levels of patients with ARF undergoing mechanical ventilation by integrating information from various techniques, each examining different aspects of lung morphology and physiology. The methods the investigators use include lung computed tomography (CT) and electrical impedance tomography (EIT). Lung CT is the reference technique for measuring the morphological response to PEEP (Gattinoni et al.). It quantifies the volume of the hyperinflated and non-aerated lung, both of which are related to the risk of mechanical ventilation causing damage (Slutsky et al.). Lung EIT monitors the functional response to PEEP in terms of changes in regional compliance across different PEEP levels. Allegedly, an increase in compliance when PEEP is decreased reveals overdistention, the functional correlate of (worrisome) hyperinflation, at the higher PEEP. A decrease in compliance when PEEP is decreased signals new collapse, the functional correlate of (worrisome) loss of aeration (Franchineau et al.).
In the Unit where the investigators work, patients with ARF treated with mechanical ventilation are routinely studied as follows. First, a lung CT with a PEEP of 20 cmH2O and then of 5 cmH2O is obtained. Thereafter, a decremental PEEP test is performed with the EIT, where PEEP is decreased from 20 cmH2O down to 5 cmH2O in steps of 2 or 3 cmH2O. Finally, results are analyzed and compared offline.
At the lung CT, decreasing PEEP from 20 to 5 cmH2O is always associated with some decrease in the volume of the hyperinflated lung and some increase in the volume of the non-aerated lung. However, the magnitude of these two effects varies among individuals, and the net response may be defined as the difference between those two competing effects. If the decrease in the volume of the hyperinflated lung is greater than the increase in the volume of the non-aerated lung, the overall response (i.e., less hyperinflation) can be considered positive. PEEP should then be set closer to 5 than to 20 cmH2O. Diversely, if the decrease in the volume of the hyperinflated lung is smaller than the increase in the volume of the non-aerated lung, the overall response (i.e., more loss of aeration) can be considered negative. PEEP should then be set closer to 20 cmH2O (Protti et al.). Similarly, at the lung EIT, decreasing PEEP from 20 to 5 cmH2O is always associated with compliance improvement in some regions (i.e., less overdistension) and worsening in others (i.e., more collapse). Again, the magnitude of these two opposite effects varies among individuals. According to most experts on lung EIT, PEEP should be set at the level where both overdistension and collapse are minimized (the so-called "best" PEEP) (Jonkman et al.).
Lung CT requires transfer to the radiology unit, exposure of the patient to radiation, and complex analysis offline. By contrast, lung EIT is virtually risk-free, and analysis can be performed using an automatic algorithm. Nevertheless, lung EIT is less well validated than lung CT. For instance, the assumption that a decrease in compliance in response to a decrease in PEEP is due to new collapse has been questioned (Protti et al., Chiumello et al., Menga et al.). So far, lung CT remains the reference technique for studying individual responses to PEEP, while lung EIT requires further validation.
This study aims to verify whether the "best" PEEP identified using lung EIT is strongly associated with the net response assessed using lung CT, when PEEP is decreased from 20 to 5 cmH2O in patients with ARF treated with mechanical ventilation. If so, this would strengthen the rationale for using the lung EIT (which is safer and simpler than the lung CT) to set PEEP.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adults admitted to the Intensive Care Unit of the IRCCS Humanitas Research Hospital, in Rozzano (Milan, Italy), with acute respiratory failure treated with mechanical ventilation
Key inclusion criteria (2 listed)
- Adults (≥18 years of age) admitted to our Unit with ARF treated with mechanical ventilation
- The patient undergoes a lung CT and EIT to guide the setting of PEEP as part of our routine clinical practice
Key exclusion criteria (2 listed)
- The patient cannot undergo a lung CT and/or EIT as judged by the attending physician (for instance, transport to the radiology unit may be considered too risky if the patient is extremely severe, or using EIT may be contraindicated because of the presence of a pacemaker)
- Pregnancy (as this condition alters the respiratory physiology)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Association Between Lung EIT and CT Findings During PEEP Titration
Time frame: Within 72 hours from the start of mechanical ventilation
The investigators will use the Spearman's correlation coefficient (rho) to measure the strength of the linear association between these two continuous variables: Y: the "best" PEEP identified with the EIT, as the PEEP level between 20 and 5 cmH2O where overdistension and collapse are minimal. This variable is measured in cmH2O. X: the overall net response to decreasing PEEP from 20 to 5 cmH2O, as assessed with the lung CT. This variable is the difference between the decrease in the volume of the hyperinflated lung and the increase in the volume of the non-aerated lung across the two PEEP levels and is measured in ml.
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 19 May 2026.
- Background: PubMed 24283226Slutsky AS, Ranieri VM. Ventilator-induced lung injury. N Engl J Med. 2013 Nov 28;369(22):2126-36. doi: 10.1056/NEJMra1208707. No abstract available.
- Background: PubMed 28146639Sahetya SK, Goligher EC, Brower RG. Fifty Years of Research in ARDS. Setting Positive End-Expiratory Pressure in Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2017 Jun 1;195(11):1429-1438. doi: 10.1164/rccm.201610-2035CI.
- Background: PubMed 16641394Gattinoni L, Caironi P, Cressoni M, Chiumello D, Ranieri VM, Quintel M, Russo S, Patroniti N, Cornejo R, Bugedo G. Lung recruitment in patients with the acute respiratory distress syndrome. N Engl J Med. 2006 Apr 27;354(17):1775-86. doi: 10.1056/NEJMoa052052.
- Background: PubMed 38127779Franchineau G, Jonkman AH, Piquilloud L, Yoshida T, Costa E, Roze H, Camporota L, Piraino T, Spinelli E, Combes A, Alcala GC, Amato M, Mauri T, Frerichs I, Brochard LJ, Schmidt M. Electrical Impedance Tomography to Monitor Hypoxemic Respiratory Failure. Am J Respir Crit Care Med. 2024 Mar 15;209(6):670-682. doi: 10.1164/rccm.202306-1118CI.
- Background: PubMed 34666011Protti A, Santini A, Pennati F, Chiurazzi C, Cressoni M, Ferrari M, Iapichino GE, Carenzo L, Lanza E, Picardo G, Caironi P, Aliverti A, Cecconi M. Lung Response to a Higher Positive End-Expiratory Pressure in Mechanically Ventilated Patients With COVID-19. Chest. 2022 Apr;161(4):979-988. doi: 10.1016/j.chest.2021.10.012. Epub 2021 Oct 16.
- Background: PubMed 37097986Jonkman AH, Alcala GC, Pavlovsky B, Roca O, Spadaro S, Scaramuzzo G, Chen L, Dianti J, Sousa MLA, Sklar MC, Piraino T, Ge H, Chen GQ, Zhou JX, Li J, Goligher EC, Costa E, Mancebo J, Mauri T, Amato M, Brochard LJ; Pleural Pressure Working Group (PLUG). Lung Recruitment Assessed by Electrical Impedance Tomography (RECRUIT): A Multicenter Study of COVID-19 Acute Respiratory Distress Syndrome. Am J Respir Crit Care Med. 2023 Jul 1;208(1):25-38. doi: 10.1164/rccm.202212-2300OC.
- Background: PubMed 26699672Chiumello D, Marino A, Brioni M, Cigada I, Menga F, Colombo A, Crimella F, Algieri I, Cressoni M, Carlesso E, Gattinoni L. Lung Recruitment Assessed by Respiratory Mechanics and Computed Tomography in Patients with Acute Respiratory Distress Syndrome. What Is the Relationship? Am J Respir Crit Care Med. 2016 Jun 1;193(11):1254-63. doi: 10.1164/rccm.201507-1413OC.
- Background: PubMed 38085857Menga LS, Subira C, Wong A, Sousa M, Brochard LJ. Setting positive end-expiratory pressure: does the 'best compliance' concept really work? Curr Opin Crit Care. 2024 Feb 1;30(1):20-27. doi: 10.1097/MCC.0000000000001121. Epub 2023 Nov 29.
- Individual participant dataSharing planned: No
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Acute Hypoxemic Respiratory Failure and Ventilation, Mechanical, run by Istituto Clinico Humanitas at 1 site in Italy.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 19 May 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Italy. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Alessandro Protti (+39 02 82244135, alessandro.protti@hunimed.eu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Association Between Lung EIT and CT Findings During PEEP Titration (time frame: Within 72 hours from the start of mechanical ventilation). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07175194, which also lists 8 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 19 May 2026.