AHRFOPTIRESTNCT07679932
Optimization of Respiratory Effort With Titrated Sedation in AHRF
An observational study of AHRF, run by Fondazione Policlinico Universitario Agostino Gemelli IRCCS at 1 site in Italy.
Trial summary
Prospective, observational, monocentric study to assess the physiological effects of dexmedetomidine and remifentanil in spontaneously breathing patients with acute hypoxemic respiratory failure receiving high-flow nasal oxygen. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- AHRF
- How many people
- 40 participants
- Where
- 1 siteItaly
- Study dates
- Jul 2026to Jul 2028
- 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: Patients with hypoxemic respiratory failure treated with high-flow oxygen therapy for whom the attending physician, based on clinical indications, has decided to initiate sedative-analgesic treatment with dexmedetomidine or remifentanil. The study plans to enroll 40 patients, including 20 patients treated with dexmedetomidine and 20 patients treated with remifentanil.
Who may be able to join
- Age ≥18 years
- PaO2/FiO2 ratio ≤ 200;
- PaCO2 < 45 mmHg;
- At least one symptom prompting the use of sedative-analgesic drugs according to the prescription of the attending physician: dyspnea and/or discomfort equal of greater than 4/10 (Visual Analog Scale - VAS), respiratory rate equal or greater than 25 breaths per minute, PaCO2<35 mmHg, pain (Numeric Rating Scale ≥ 4 or Behavioral Pain Scale - Non-Intubated ≥ 4);
- Informed consent signature.
Who cannot join
- Pregnancy;
- Exacerbation of asthma or chronic obstructive pulmonary disease;
- Chronic lung disease, requiring oxygen therapy at home;
- Cardiogenic pulmonary oedema;
- Hemodynamic instability (systolic blood pressure <90 mmHg or mean arterial pressure <65 mmHg) and/or lactic acidosis (lactate >5 mmol/L) and/or clinically diagnosed shock;
- Metabolic acidosis (pH <7.30 with normal or hypocarbia);
- Glasgow Coma Scale <13;
- Contraindications to esophageal balloon and/or EIT placement.
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
Fondazione Policlinico Universitario A.Gemelli IRCCS
Roma, RM, 00168
Domenico Luca Grieco, MD, +393397681623, dlgrieco@outlook.it
About this study
Official title: Optimization of Respiratory Effort With Titrated Sedation in Patients With Acute Hypoxemic Respiratory Failure - The OPTIREST Study
Prospective, observational, monocentric study to assess the physiological effects of dexmedetomidine and remifentanil in spontaneously breathing patients with acute hypoxemic respiratory failure receiving high-flow nasal oxygen.
Read the detailed description
Sedation in spontaneously breathing hypoxemic patients represents a critical physiological trade-off between lung protection and maintenance of adequate ventilation. While spontaneous breathing is generally encouraged to preserve diaphragm function and avoid invasive ventilation, excessive respiratory drive may promote patient self-inflicted lung injury (P-SILI) through increased inspiratory effort, elevated transpulmonary pressure swings, pendelluft phenomena, and regional stress amplification. Conversely, excessive sedation may suppress respiratory drive, resulting in hypoventilation, impaired gas exchange, and diaphragm disuse. Sedation therefore behaves as a double-edged sword, requiring careful titration to balance lung protection and adequate ventilation. Despite the widespread use of dexmedetomidine and remifentanil in this setting, limited information is available regarding their dose-dependent physiological effects on inspiratory effort, transpulmonary pressure, regional ventilation distribution, expiratory muscle recruitment, and lung stress. Current clinical practice relies mainly on symptom control (dyspnea, agitation, tachypnea) without direct assessment of the mechanical and regional effects of sedation on the injured lung; consequently, sedation strategies remain largely empirical and poorly standardized. The study aims to characterize the effects of sedation administered through Target-Controlled Infusion (TCI) on respiratory mechanics and regional lung behavior in spontaneously breathing patients receiving high-flow nasal oxygen. By integrating esophageal pressure monitoring and electrical impedance tomography, the effects of increasing effect-site concentrations of dexmedetomidine or remifentanil on inspiratory effort and its regional consequences will be investigated.
- Conditions
- AHRF
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Dexmedetomidine during HFNC | The procedure performed as part of routine clinical practice involves the administration of high-flow nasal oxygen therapy (HFNC), with an initial flow set at 60 L/min, potentially reduced to the maximum tolerated flow in case of discomfort. FiO₂ is titrated to maintain the target SpO₂ of 92-96%. Humidification chamber is heated at 37°C or 34°C according to patient's comfort. During the procedure, patients receive sedative-analgesic treatment with dexmedetomidine as a clinical indication decided by the attending physician. | |
| Remifentanil during HFNC | The procedure performed as part of routine clinical practice involves the administration of high-flow nasal oxygen therapy (HFNC), with an initial flow set at 60 L/min, potentially reduced to the maximum tolerated flow in case of discomfort. FiO₂ is titrated to maintain the target SpO₂ of 92-96%. Humidification chamber is heated at 37°C or 34°C according to patient's comfort. During the procedure, patients receive sedative-analgesic treatment with remifentanil as a clinical indication decided by the attending physician. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Inspiratory effort, expressed in cmH2O
Negative deflection in esophageal pressure during inspiration
Measured: During procedure
Secondary outcomes (13)
Dyspnea
Defined according to visual analog scale of dyspnea (0-10, where 10 represents worst perceivable dyspnea)
Measured: During procedure
Discomfort
Defined according to visual analog scale of discomfort (0-10, where 10 represents worst perceivable discomfort).
Measured: During procedure
PaO2/FiO2 ratio
Change in arterial Pa/FiO2 (in mmHg)
Measured: During procedure
Respiratory rate
Change in respiratory rate (breaths/minute)
Measured: During procedure
Recuitment of expiratory muscles, expressed in cmH2O of gastric pressure
Expiratory increases in gastric pressure
Measured: During procedure
Tidal volume distribution
Tidal volume distribution in the different lung regions (ventral-midventral-middorsal-dorsal), assessed with electrical impedance tomography
Measured: During procedure
End-expiratory lung volume
Global impedance-derived end-expiratory lung volume (EELI), measured with electrical impedance tomography
Measured: During procedure
Regional End-expiratory lung volume
Regional (ventral-midventral-middorsal-dorsal) impedance-derived end-expiratory lung volume (EELI), measured with electrical impedance tomography
Measured: During procedure
Dynamic transpulmonary driving pressure
Tidal change in transpulmonary pressure assessed with esophageal catether
Measured: During procedure
Global impedance-derived lung dynamic strain
Change in impedance due to tidal volume / end expiratory lung impedance, both measured with electrical impedance tomography
Measured: During procedure
Regional impedance-derived lung dynamic strain
Change in impedance due to tidal volume / end expiratory lung impedance in the four regions of the lungs (ventral, mid-ventral, mid-dorsal, dorsal), measured with electrical impedance tomography
Measured: During procedure
Pendelluft
Occurrence of intra-tidal shift of gas within different lung regions at beginning of inspiration
Measured: During procedure
Work of breathing
Esophageal pressure simplified pressure time product per minute
Measured: During procedure
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Jul 2026
- Study startJul 2026 (estimated)
- Primary completionJun 2028 (estimated)
- Study completionJul 2028 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for AHRFStudies of the same condition, open and under way.
- More trials run by Fondazione Policlinico Universitario Agostino Gemelli IRCCSThe sponsor's other registered studies.
- 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
- Other
- Time perspective
- Prospective
- Enrolment
- 40 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, GRIECO DOMENICO LUCA, Fondazione Policlinico Universitario Agostino Gemelli IRCCS
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07679932
- Sponsor's protocol ID
- 27387-1
- Acronym
- OPTIREST
- Status last verified
- Jun 2026
- First submitted
- 17 Jun 2026
- Last updated
- 1 Jul 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 1 Jul 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Optimization of Respiratory Effort With Titrated Sedation in Patients With Acute Hypoxemic Respiratory Failure - The OPTIREST Study
- ClinicalTrials.gov ID
- NCT07679932
- Acronym / sponsor ID
- OPTIREST / 27387-1
- Conditions
- AHRF
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 40 participants (estimated)
- Lead sponsor
- Fondazione Policlinico Universitario Agostino Gemelli IRCCSUniversity, hospital or other
- Study start
- Jul 2026 (estimated)
- Primary completion
- Jun 2028 (estimated)
- Study completion
- Jul 2028 (estimated)
- First posted
- 1 Jul 2026 (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.
Prospective, observational, monocentric study to assess the physiological effects of dexmedetomidine and remifentanil in spontaneously breathing patients with acute hypoxemic respiratory failure receiving high-flow nasal oxygen.
Detailed description
Sedation in spontaneously breathing hypoxemic patients represents a critical physiological trade-off between lung protection and maintenance of adequate ventilation. While spontaneous breathing is generally encouraged to preserve diaphragm function and avoid invasive ventilation, excessive respiratory drive may promote patient self-inflicted lung injury (P-SILI) through increased inspiratory effort, elevated transpulmonary pressure swings, pendelluft phenomena, and regional stress amplification. Conversely, excessive sedation may suppress respiratory drive, resulting in hypoventilation, impaired gas exchange, and diaphragm disuse. Sedation therefore behaves as a double-edged sword, requiring careful titration to balance lung protection and adequate ventilation. Despite the widespread use of dexmedetomidine and remifentanil in this setting, limited information is available regarding their dose-dependent physiological effects on inspiratory effort, transpulmonary pressure, regional ventilation distribution, expiratory muscle recruitment, and lung stress. Current clinical practice relies mainly on symptom control (dyspnea, agitation, tachypnea) without direct assessment of the mechanical and regional effects of sedation on the injured lung; consequently, sedation strategies remain largely empirical and poorly standardized. The study aims to characterize the effects of sedation administered through Target-Controlled Infusion (TCI) on respiratory mechanics and regional lung behavior in spontaneously breathing patients receiving high-flow nasal oxygen. By integrating esophageal pressure monitoring and electrical impedance tomography, the effects of increasing effect-site concentrations of dexmedetomidine or remifentanil on inspiratory effort and its regional consequences will be investigated.
Study design
- Observational model
- Other
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Dexmedetomidine during HFNC | – | –The procedure performed as part of routine clinical practice involves the administration of high-flow nasal oxygen therapy (HFNC), with an initial flow set at 60 L/min, potentially reduced to the maximum tolerated flow in case of discomfort. FiO₂ is titrated to maintain the target SpO₂ of 92-96%. Humidification chamber is heated at 37°C or 34°C according to patient's comfort. During the procedure, patients receive sedative-analgesic treatment with dexmedetomidine as a clinical indication decided by the attending physician. |
| Remifentanil during HFNC | – | –The procedure performed as part of routine clinical practice involves the administration of high-flow nasal oxygen therapy (HFNC), with an initial flow set at 60 L/min, potentially reduced to the maximum tolerated flow in case of discomfort. FiO₂ is titrated to maintain the target SpO₂ of 92-96%. Humidification chamber is heated at 37°C or 34°C according to patient's comfort. During the procedure, patients receive sedative-analgesic treatment with remifentanil as a clinical indication decided by the attending physician. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with hypoxemic respiratory failure treated with high-flow oxygen therapy for whom the attending physician, based on clinical indications, has decided to initiate sedative-analgesic treatment with dexmedetomidine or remifentanil. The study plans to enroll 40 patients, including 20 patients treated with dexmedetomidine and 20 patients treated with remifentanil.
Key inclusion criteria (5 listed)
- Age ≥18 years
- PaO2/FiO2 ratio ≤ 200;
- PaCO2 < 45 mmHg;
- At least one symptom prompting the use of sedative-analgesic drugs according to the prescription of the attending physician: dyspnea and/or discomfort equal of greater than 4/10 (Visual Analog Scale - VAS), respiratory rate equal or greater than 25 breaths per minute, PaCO2<35 mmHg, pain (Numeric Rating Scale ≥ 4 or Behavioral Pain Scale - Non-Intubated ≥ 4);
- Informed consent signature.
Key exclusion criteria (8 listed)
- Pregnancy;
- Exacerbation of asthma or chronic obstructive pulmonary disease;
- Chronic lung disease, requiring oxygen therapy at home;
- Cardiogenic pulmonary oedema;
- Hemodynamic instability (systolic blood pressure <90 mmHg or mean arterial pressure <65 mmHg) and/or lactic acidosis (lactate >5 mmol/L) and/or clinically diagnosed shock;
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
Inspiratory effort, expressed in cmH2O
Time frame: During procedure
Negative deflection in esophageal pressure during inspiration
13 secondary outcomes
Dyspnea
Time frame: During procedure
Discomfort
Time frame: During procedure
PaO2/FiO2 ratio
Time frame: During procedure
Respiratory rate
Time frame: During procedure
Recuitment of expiratory muscles, expressed in cmH2O of gastric pressure
Time frame: During procedure
Tidal volume distribution
Time frame: During procedure
End-expiratory lung volume
Time frame: During procedure
Regional End-expiratory lung volume
Time frame: During procedure
Dynamic transpulmonary driving pressure
Time frame: During procedure
Global impedance-derived lung dynamic strain
Time frame: During procedure
Regional impedance-derived lung dynamic strain
Time frame: During procedure
Pendelluft
Time frame: During procedure
Work of breathing
Time frame: During procedure
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 1 Jul 2026.
- Individual participant dataSharing planned: Undecided
Related trials for AHRF
Recruiting
STimulation to Activate RespIration
ARDS (Moderate or Severe), AHRF
RecruitingPhase 2
A Clinical Trial to Evaluate agenT-797 Plus Standard of Care in Participants With Severe Pneumonia With Moderate to Severe Acute Hypoxemic Respiratory Failure
Pneumonia
RecruitingObservational study
Predicting High-Flow Nasal Cannula Failure in Acute Hypoxemic Respiratory Failure Using Metabolomics and Clinical Data
Acute Hypoxemic Respiratory Failure
Active, not recruitingPhase 2
I-SPY COVID-19 TRIAL: An Adaptive Platform Trial for Critically Ill Patients
COVID-19
Not yet recruiting
HemodynamIc eFfects of Lung Collapse and overdIstension During ARDS
ARDS, AHRF
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 AHRF, run by Fondazione Policlinico Universitario Agostino Gemelli IRCCS 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 5 inclusion and 8 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: opening soon, as of the sponsor's last update on 1 Jul 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 Domenico Luca Grieco, MD (+393397681623, dlgrieco@outlook.it), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Inspiratory effort, expressed in cmH2O (time frame: During procedure). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
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 1 Jul 2026.