Assessment of the Cerebral Perfusion During the Period of Deep Hypothermia at 18°C in Patient Undergoing Pulmonary Endarterectomy Surgery.

Study Purpose

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.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

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Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - 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.

Exclusion Criteria:

  • - Patient refusing to participate in the study.
  • - Patient under guardianship.
  • - Patient deprived of liberty.
  • - Pregnant or breast-feeding women.

Trial Details

Trial ID:

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Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

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Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

Fondation Hôpital Saint-Joseph
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

Principal Investigator Affiliation N/A
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Overall Status Recruiting
Countries France

The disease, disorder, syndrome, illness, or injury that is being studied.

Hypothermia, Cerebral Perfusion, Transcranial Doppler Ultrasound, Pulmonary Hypertension
Arms & Interventions


Experimental: Patients with thromboendarterectomy surgery

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.


Procedure: - Bilateral trans-cranial Doppler ultrasound

Velocity measurements in the middle cerebral artery are made using an ultrasound probe applied to the patient's temple during surgery.

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International Sites

Hôpital Marie Lannelongue, Le Plessis-Robinson, France




Hôpital Marie Lannelongue

Le Plessis-Robinson, , 92350

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