Mild vs Moderate Hypothermic Circulatory Arrest With Unilateral Anterograde Cerebral Perfusion in Hemiarch Replacement
Condition: Aortic Aneurysm
MeSH terms: Aneurysm; Aortic Aneurysm
Study type: Interventional

Summary: 
      The aim of our study is to analyze the immediate and long-term results between patients
      undergoing hemiarch replacement with ACP under mild hypothermic (30-32 °C) circulatory arrest
      versus moderate hypothermic (26-28 °C) circulatory arrest. It is hypothesized that
      circulatory arrest using mild hypothermia (30-32°C) and uSACP will result in complications
      reduction, during aortic hemiarch replacement, when compared to moderate hypothermia
      (26-28°C) and uSACP. For this purpose all of the patient population will be randomized into 2
      groups. The first group of the patients during aortic hemiarch replacement, mild hypothermia
      (30-32°C) will be used during circulatory arrest. The second group of the patients during
      aortic hemiarch replacement, moderate hypothermia (26-28°C) will be used during circulatory
      arrest.
    

Detailed description: 
      Mild versus moderate hypothermic circulatory arrest during aortic hemiarch replacement
      Hypothermic circulatory arrest with unilateral selective anterograde cerebral perfusion
      (SACP) is an important surgical technique, allowing complex aortic surgeries to be performed
      safely. One of the main positive aspects of the strategy for changing the hypothermia
      temperature is to reduce the systemic inflammatory response, minimize visceral organ
      dysfunction, and reduce the risk of postoperative bleeding - the adverse effects of
      hypothermia Patients will be operated for ascending aortic aneurysm in a hypothermic
      circulatory arrest with unilateral SACP. The main difference is during aortic hemiarch
      replacement, moderate hypothermia (26-28°C) and mild hypothermia (30-32°C) will be used
      during circulatory arrest. All data will be prospectively collected and recorded. All
      surgeries will be perform concurrently in the same time period. Experienced in aortic
      pathology surgeons will perform these operations.

      Description of the procedures:

      All surgical procedures will be performed via median sternotomy. During the aortic arch
      anastomosis, continuous, unilateral SACP using innominate artery will be employed. Unilateral
      SACP may be converted to bilateral ACP at the surgeon's discretion if adequate cerebral flows
      are not achieved or if there are concerns with cerebral oximetry measurements.

      Once on CPB, the patient will be cooled to a nasopharyngeal (NP) temperature of either 30-32
      °C or 26-28 °C, depending on to which treatment arm the patient has been randomized. Rectal
      temperature with be monitored as an additional temperature sites. Unilateral SACP will only
      be initiated once the target temperature has been reached. SACP via the innominate artery
      will be commenced with target flows of 8-10 ml/kg/min and perfusion pressure of 60-80 mmHg.
      Perfusion adequacy will be evaluated using measurement of blood pressure in both radial
      arteries and cerebral oximetry using near-infrared spectroscopy (NIRS).

      After completion of the aortic hemiarch replacement, CPB will be resumed and the patient
      re-warmed to 36 °C prior to coming off CPB, with a = 1 °C temperature difference between
      temperature monitoring sites (NP and rectal).

      Intraoperative information will be collected from the anesthetic record, surgical notes and
      perfusion records. Intraoperative data collection will include total operative time, CPB
      time, cross-clamp time, hypothermic cardiac arrest time, uSACP time, lowest nasopharyngeal
      and rectal temperature, arterial pressure in both radial arteries, perfusion rate and
      perfusion pressure during both of CPB and unilateral SACP, lowest hemoglobin concentration
      (g/L) and hematocrit (%), acid-base indices, intraoperative red blood cell transfusion
      (units), highest dose/agent used for intraoperative inotrope or vasopressor support. Also
      during the surgery will be performed NIRS and BIS-monitoring.

      Postoperative data will include valuation of following indicators: mortality (hospital
      mortality and death from any cause); neurological injury (TIA, stroke, delirium), MRI and
      CT-scan only in event of postoperative stroke; acute kidney injury (creatinine level prior
      and 1, 2, 4 postoperative day (POD), urine output-up to 24-48 h, renal replacement therapy
      (dialysis); time of mechanical ventilation; re-exploration for bleeding, tamponade or other
      reasons; postoperative transfusion (packed red blood cells, platelets, fresh frozen
      platelets, cryoprecipitate); postoperative myocardial infarction (electrocardiogram and
      troponins); inotropic support during 24-48 h (agent and dose (VIS)); length of stay
      (intensive care unit and total hospital days).

      Before surgery and on 12-16 POD, patients will undergo neurocognitive screening by trained
      personnel. Neurocognitive tests will include: MOCA examinations, Schulte Table and The
      Bourdon Test.

      In addition, indicators of specific markers of brain damage will be evaluated. Indicators
      such as neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), brain-derived
      neurotrophic factor (BDNF) will be evaluated before surgery and on first POD. Also will be
      evaluated indicators of the hemostatic system: thrombin-antithrombin (TAT) complexes,
      prothrombin fragments 1+2, glu-plasminogen, tissue plasminogen activator (t-PA), endothelin
      1-21 and thromboelastography (TEG) in following points - before surgery, lowest temperature
      during arrest time, after inactivation of heparin and 4 h after surgery.

      Follow-up information will be collected using direct or phone contact with patients,
      relatives, or physicians.
    

Intervention name(s): Hypothermic circulatory arrest with unilateral selective anterograde cerebral perfusion
Intervention type(s): Procedure
Intervention description(s): Hypothermic circulatory arrest provides protection to cerebral and visceral organs.
Allocation: Randomized
Intervention model: Parallel Assignment
Intervention model description: The total patient population will be randomized into 2 groups. The first group of the patients during aortic hemiarch replacement, mild hypothermia (30-32°C) will be used during circulatory arrest. (main group). The second group of the patients during aortic hemiarch replacement, moderate hypothermia (26-28°C) will be used during circulatory arrest. (control group).
Masking: Double (Participant, Outcomes Assessor)
Primary purpose: Treatment