A Comparative Study of Different Hypothermic Circulatory Arrest Strategies on Aortic Surgery.

Study Overview
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Brief Summary
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By comparing the clinical outcome of patients underwent different hypothermic circulatory arrest (mild hypothermic versus moderate hypothermic) during aortic arch surgery, this study aims to determine the optimal hypothermic circulatory arrest strategy for aortic surgery.

Detailed Description
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Hypothermic circulatory arrest (HCA) is the cornerstone of aortic surgery. It provides a bloodless and still operative field. But the side effect of hypothermia also draws people's concern. With the development of surgical techniques and cardiopulmonary bypass (CPB) management, the temperature of HCA has been raised from deep hypothermia (14.1-20 degree) to moderate hypothermia (20.1-28 degree), and it has been a primary choice for many surgeons around the world. Some of surgeons still tried to push the limit and started using mild hypothermia (28.1-34 degree), and satisfactory outcome was obtained. However, the optimal temperature of HCA has not yet been determined. In this randomized controlled study, 80 informed and consenting patients who are scheduled for total arch replacement with concomitant proximal aortic reconstruction will be randomized to mild (28.1-34 degree) or moderate (20.1-28 degree) hypothermia during circulatory arrest. Clinical outcomes of both groups will be analyzed to determine the optimal temperature for HCA.

Official Title
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A Comparative Study of Mild Hypothermic Circulatory Arrest Versus Moderate Hypothermic Circulatory Arrest on Aortic Surgery.

Conditions
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Aortic-cross Clamping Time, Morality, Hypothermic Circulatory Arrest Time, Cardiopulmonary Bypass Time, Operation Time, Re-Thoracotomy, ICU Stay, Mechanical Ventilation Time, Blood Transfusion, Neurological Disorder, Dialysis, Aneurysm, Endoleak, Hospital Stay

Intervention / Treatment
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* Procedure: the temperature of hypothermic circulatory arrest


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 1.Patients with confirmed diagnosis (i.e.aortic dissection, marfan syndrome, aortic arch aneurysm and so on), which require total aortic arch replacement. Exclusion Criteria: Preoperative heart attack or coma. Patients with surgical contraindication, including but not limited to severe cardiac,pulmonary,renal or hepatic insufficiency. Pre-existing heart condition or neurological disease. Variation of aortic arch or its branch vessels. Patient is currently on anticoagulation therapy or has other medical condition that compromises the coagulation. Patient with active infection. Allergy to anaesthetic or contrast agent. Pregnant or lactating female. Patient is already on other medical trial. Other medical, psychological or socioeconomics condition determined by investigator that is not eligible for the study.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: A randomised controlled study
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Mild hypothermia<br>Initiation of circulatory arrest using the cardiopulmonary bypass at temperature 28.1 - 34 degrees Celsius | Procedure: the temperature of hypothermic circulatory arrest<br>* Different temperature (mild 30 degree or moderate 25 degree) employed during the hypothermic circulatory arrest on aortic surgery.<br>|
| Active Comparator: Moderate hypothermia<br>Initiation of circulatory arrest using the cardiopulmonary bypass at temperature 20.1 - 28 degrees Celsius | Procedure: the temperature of hypothermic circulatory arrest<br>* Different temperature (mild 30 degree or moderate 25 degree) employed during the hypothermic circulatory arrest on aortic surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mortality | In-hospital Mortality or other related death | 3 months within surgery. | 
| Re-thoracotomy | Postoperative bleeding or other conditions require re-thoracotomy | Through the hospitalization, an average of 4 weeks. | 
| Neurological disorder | Any neurological event occur after surgery, including transient and permanent. | Through the hospitalization, an average of 4 weeks. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| HCA time | the time of hypothermic circulatory arrest | During the operation | 
| Aorta-cross clamp time | the time of aortic-cross clamp | During the operation | 
| CPB time | the time of cardiopulmonary bypass | During the operation | 
| Operation time | the time of the entire surgery. | During the operation | 
| ICU stay | the day of ICU treatment | Through the ICU stay, an average of 1 weeks. | 
| Time of mechanical ventilation | the time of using respirator | Through the use of ventilation, an average of 3 days. | 
| Blood transfusion | the number of blood product during the hospitalization, including red blood cell, platelet, plasma and so on. | Through the hospitalization, an average of 4 weeks. | 
| Dialysis | postoperative renal failure requiring dialysis | Through the hospitalization, an average of 4 weeks. | 
| Hospital stay | the time of hospitalization | Through the hospitalization, an average of 4 weeks. | 
| Postoperative aneurysm | Aortic aneurysm develope after the surgery | 1 year within the surgery | 
| Postoperative endoleak | Stent-graft endoleak occurs after the surgery. | 1 year within the surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hyperthermic circulatory arrest; Surgery