HypothermiaHYPO-TEPNCT06250374
Assessment of the Cerebral Perfusion During the Period of Deep Hypothermia at 18°C in Patient Undergoing Pulmonary Endarterectomy Surgery.
A study testing Bilateral trans-cranial Doppler ultrasound in people with Hypothermia and Cerebral Perfusion, run by Fondation Hôpital Saint-Joseph at 1 site in France.
Trial summary
Cardiopulmonary bypass (CPB) surgery present risk of acute postoperative neurological complications. These complications are most often postoperative cognitive dysfunction (confusion, cognitive disorders, executive disorders) with a prevalence of up to 40% at 5 years, and ischemic (stroke) with an incidence of between… Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Hypothermia, Cerebral Perfusion, Transcranial Doppler Ultrasound
- What is being tested?
- Bilateral trans-cranial Doppler ultrasound
- Type of treatment
- Injection or infusion, Surgery or procedure
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 45 participants
- Where
- 1 siteFrance
- Study dates
- 24 Aug 2023to 24 May 2025
- Phase
- Interventional
- 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
Who may be able to join
- Scheduled for pulmonary artery thromboendarterectomy surgery.
- Patient with free, written and informed consent.
- Patient affiliated to a social security scheme (beneficiary or beneficiary's beneficiary).
- French-speaking patient.
Who cannot join
- Patient refusing to participate in the study.
- Patient under guardianship.
- Patient deprived of liberty.
- Pregnant or breast-feeding women.
Trial locations and contacts
1 site in 1 country.
About this study
Cardiopulmonary bypass (CPB) surgery present risk of acute postoperative neurological complications. These complications are most often postoperative cognitive dysfunction (confusion, cognitive disorders, executive disorders) with a prevalence of up to 40% at 5 years, and ischemic (stroke) with an incidence of between 0.4 and 14%. The causes are usually multifactorial, but altered cerebral perfusion during CPB surgery is an important prognostic factor. Data regarding the effect of deep hypothermia on cerebral perfusion during CPB in adult are scarce. Currently, aortic arch replacement following aortic dissection or aneurysm, and pulmonary artery endarterectomy (PAE) in the treatment of pulmonary hypertension of post embolic origin are performed under deep hypothermia.
In this latter indication, the need to obtain a completely bloodless operating field necessitates complete circulatory arrest during short period of time to enable the surgeon to optimally remove the clot materials located into the pulmonary arteries.
Read more
To protect the brain and avoid irreversible brain injury during circulatory arrest(s), body temperature is lowered at 18-20°C. Deep hypothermia can lead to significant arterial vasoconstriction, which can reduce the blood supply to the brai. It also increases the solubility of CO2 in the blood, leading to respiratory alkalosis, which can also lead to vasoconstriction of cerebral vessels, increasing the risk of ischemic lesions.
In adult there is no consistent data on the cerebral perfusion during PAE surgery under deep hypothermia at 18-20°C. Animal studies showed that cerebral regulation seems to be preserved under these conditions. A better understanding of the effect of deep hypothermia on cerebral perfusion during PAE surgery is essential to adapt our management to limit the occurrence of postoperative neurological complications.
- Being tested
- Bilateral trans-cranial Doppler ultrasound
- Keywords
- Pulmonary endarterectomy, cerebral perfusion, Hypothermia, Transcranial doppler ultrasound, Cardiopulmonary bypass
- Medical subject headings
- Hypothermia, Hypertension, Pulmonary
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Bilateral trans-cranial Doppler ultrasoundProcedure or surgery
Velocity measurements in the middle cerebral artery are made using an ultrasound probe applied to the patient's temple during surgery.
| Study group | Role | What they receive |
|---|---|---|
| Patients with thromboendarterectomy surgery | Experimental | Anesthesia was induced with sufentanil 0.3 g/kg, etomidate 0.3-0.4 mg/kg, rocuronium 0.4 mg/kg and maintained with continuous infusion Propofol and sufentanil. A pulmonary arterial catheter was inserted in all patients. Patients were cooled by means of the oxygenator heat exchanger at a rate of one degree Celsius every three minutes. Rewarming was achieved at a rate of one degree Celsius every five to ten minutes.
The following measures were performed:
Measure 1: In normo-thermia after induction of general anesthesia Measure 2: On CPB, before circulatory arrest and in hypothermia at 18-20°C Measure 3: On bypass, after circulatory arrest and in hypothermia at 18-20°C Measure 4: At the end of the procedure, after weaning from the bypass and in normothermia.
For each measure mean arterial pressure, cardiac output, PaCO2, pH, bilateral NIRS value were also recorded. Receives: Procedure: Bilateral trans-cranial Doppler ultrasound |
What is being measured
The primary outcome is the main question the study is designed to answer.
Assessment of cerebral blood perfusion during deep hypothermia
Cerebral blood perfusion during deep hypothermia (18-20°C) will be assessed by measuring mean blood flow velocities in the middle cerebral arteries (MCAs) using trans-cranial Doppler ultrasound (DTC) at different time of the surgery (Four measures in total). All measure are performed during the time of the surgery. The first measure (M1) is baseline to which the other measure will be compared to.
Measured: M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Secondary outcomes (2)
Correlation between NIRS and middle cerebral arteries velocity values for each measure.
For each measure of middle cerebral arteries blood flow velocity performed during the surgery, the value of the near infrared spectroscopy (NIRS) is recorded. A total of four measures is performed during the time of the surgery.
Measured: M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Seek for post-circulatory arrest hyperemia
Comparison of the middle cerebral arteries blood flow velocities during the period of hypothermia, before and after cardiac arrest.
Measured: M2: During CPB after cooling at 18°C before cardiac arrest (H2). M3: After cardiac arrest at 18°C before rewarming period (H4).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted9 Feb 2024
- Study start24 Aug 2023
- Primary completion24 Feb 2025
- Study completion24 May 2025 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for HypothermiaStudies 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
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 45 participants (actual)
Sponsor and investigators
- Lead sponsor
- Fondation Hôpital Saint-Joseph
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06250374
- Sponsor's protocol ID
- 2023-A00270-45
- Acronym
- HYPO-TEP
- Status last verified
- Mar 2025
- First submitted
- 12 Jan 2024
- Last updated
- 13 Mar 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Liu Y, Chen K, Mei W. Neurological complications after cardiac surgery: anesthetic considerations based on outcome evidence. Curr Opin Anaesthesiol. 2019 Oct;32(5):563-567. doi: 10.1097/ACO.0000000000000755.
PubMed 31145196Brown CH 4th, Neufeld KJ, Tian J, Probert J, LaFlam A, Max L, Hori D, Nomura Y, Mandal K, Brady K, Hogue CW; Cerebral Autoregulation Study Group; Shah A, Zehr K, Cameron D, Conte J, Bienvenu OJ, Gottesman R, Yamaguchi A, Kraut M. Effect of Targeting Mean Arterial Pressure During Cardiopulmonary Bypass by Monitoring Cerebral Autoregulation on Postsurgical Delirium Among Older Patients: A Nested Randomized Clinical Trial. JAMA Surg. 2019 Sep 1;154(9):819-826. doi: 10.1001/jamasurg.2019.1163.
PubMed 31116358
Study at a glance
From the registry record, last updated by the sponsor on 13 Mar 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Assessment of the Cerebral Perfusion During the Period of Deep Hypothermia at 18°C in Patient Undergoing Pulmonary Endarterectomy Surgery.
- ClinicalTrials.gov ID
- NCT06250374
- Acronym / sponsor ID
- HYPO-TEP / 2023-A00270-45
- Keywords
- Pulmonary endarterectomy, cerebral perfusion, Hypothermia, Transcranial doppler ultrasound, Cardiopulmonary bypass
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 45 participants (actual)
- Lead sponsor
- Fondation Hôpital Saint-JosephUniversity, hospital or other
- Study start
- 24 Aug 2023 (actual)
- Primary completion
- 24 Feb 2025 (actual)
- Study completion
- 24 May 2025 (estimated)
- First posted
- 9 Feb 2024 (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.
Cardiopulmonary bypass (CPB) surgery present risk of acute postoperative neurological complications. These complications are most often postoperative cognitive dysfunction (confusion, cognitive disorders, executive disorders) with a prevalence of up to 40% at 5 years, and ischemic (stroke) with an incidence of between 0.4 and 14%. The causes are usually multifactorial, but altered cerebral perfusion during CPB surgery is an important prognostic factor. Data regarding the effect of deep hypothermia on cerebral perfusion during CPB in adult are scarce. Currently, aortic arch replacement following aortic dissection or aneurysm, and pulmonary artery endarterectomy (PAE) in the treatment of pulmonary hypertension of post embolic origin are performed under deep hypothermia.
In this latter indication, the need to obtain a completely bloodless operating field necessitates complete circulatory arrest during short period of time to enable the surgeon to optimally remove the clot materials located into the pulmonary arteries.
To protect the brain and avoid irreversible brain injury during circulatory arrest(s), body temperature is lowered at 18-20°C. Deep hypothermia can lead to significant arterial vasoconstriction, which can reduce the blood supply to the brai. It also increases the solubility of CO2 in the blood, leading to respiratory alkalosis, which can also lead to vasoconstriction of cerebral vessels, increasing the risk of ischemic lesions.
In adult there is no consistent data on the cerebral perfusion during PAE surgery under deep hypothermia at 18-20°C. Animal studies showed that cerebral regulation seems to be preserved under these conditions. A better understanding of the effect of deep hypothermia on cerebral perfusion during PAE surgery is essential to adapt our management to limit the occurrence of postoperative neurological complications.
Study design
- Primary purpose
- Other
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Patients with thromboendarterectomy surgery | Experimental | Procedure: Bilateral trans-cranial Doppler ultrasoundAnesthesia was induced with sufentanil 0.3 g/kg, etomidate 0.3-0.4 mg/kg, rocuronium 0.4 mg/kg and maintained with continuous infusion Propofol and sufentanil. A pulmonary arterial catheter was inserted in all patients. Patients were cooled by means of the oxygenator heat exchanger at a rate of one degree Celsius every three minutes. Rewarming was achieved at a rate of one degree Celsius every five to ten minutes. The following measures were performed: Measure 1: In normo-thermia after induction of general anesthesia Measure 2: On CPB, before circulatory arrest and in hypothermia at 18-20°C Measure 3: On bypass, after circulatory arrest and in hypothermia at 18-20°C Measure 4: At the end of the procedure, after weaning from the bypass and in normothermia. For each measure mean arterial pressure, cardiac output, PaCO2, pH, bilateral NIRS value were also recorded. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Scheduled for pulmonary artery thromboendarterectomy surgery.
- Patient with free, written and informed consent.
- Patient affiliated to a social security scheme (beneficiary or beneficiary's beneficiary).
- French-speaking patient.
Key exclusion criteria (4 listed)
- Patient refusing to participate in the study.
- Patient under guardianship.
- Patient deprived of liberty.
- Pregnant or breast-feeding women.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Bilateral trans-cranial Doppler ultrasoundVelocity measurements in the middle cerebral artery are made using an ultrasound probe applied to the patient's temple during surgery. | Procedure or surgery | Patients with thromboendarterectomy surgery |
Primary outcome
Assessment of cerebral blood perfusion during deep hypothermia
Time frame: M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Cerebral blood perfusion during deep hypothermia (18-20°C) will be assessed by measuring mean blood flow velocities in the middle cerebral arteries (MCAs) using trans-cranial Doppler ultrasound (DTC) at different time of the surgery (Four measures in total). All measure are performed during the time of the surgery. The first measure (M1) is baseline to which the other measure will be compared to.
2 secondary outcomes
Correlation between NIRS and middle cerebral arteries velocity values for each measure.
Time frame: M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)
Seek for post-circulatory arrest hyperemia
Time frame: M2: During CPB after cooling at 18°C before cardiac arrest (H2). M3: After cardiac arrest at 18°C before rewarming period (H4).
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 13 Mar 2025.
- Background: PubMed 31145196Liu Y, Chen K, Mei W. Neurological complications after cardiac surgery: anesthetic considerations based on outcome evidence. Curr Opin Anaesthesiol. 2019 Oct;32(5):563-567. doi: 10.1097/ACO.0000000000000755.
- Background: PubMed 31116358Brown CH 4th, Neufeld KJ, Tian J, Probert J, LaFlam A, Max L, Hori D, Nomura Y, Mandal K, Brady K, Hogue CW; Cerebral Autoregulation Study Group; Shah A, Zehr K, Cameron D, Conte J, Bienvenu OJ, Gottesman R, Yamaguchi A, Kraut M. Effect of Targeting Mean Arterial Pressure During Cardiopulmonary Bypass by Monitoring Cerebral Autoregulation on Postsurgical Delirium Among Older Patients: A Nested Randomized Clinical Trial. JAMA Surg. 2019 Sep 1;154(9):819-826. doi: 10.1001/jamasurg.2019.1163.
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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. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Bilateral trans-cranial Doppler ultrasound in people with Hypothermia and Cerebral Perfusion, run by Fondation Hôpital Saint-Joseph at 1 site in France.
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 4 inclusion and 4 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: under way, not looking for participants, as of the sponsor's last update on 13 Mar 2025. 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 France. 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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Assessment of cerebral blood perfusion during deep hypothermia (time frame: M1: Baseline-normothermia after induction of general anesthesia (H0) M2: During CPB-at 18°C-before cardiac arrest (H2) M3: After cardiac arrest-at 18°C before (H4) M4: End of surgery-normothermia (H6)). 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 NCT06250374, which also lists 2 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 13 Mar 2025.