Restrictive Transfusion StratEgy Adjusted by SvO2 During Cardiac Surgery

Study Overview
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Brief Summary
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The goal of the clinical trial is to evaluate whether a restrictive transfusion strategy adjusted by SvO2 during the perioperative period of cardiac surgery may reduce the incidence of red blood cell transfusion. Adult patients operated on cardiac surgery will be randomly allocated into two groups, one receiving standard restrictive transfusion, the other receiving SvO2 adjusted restrictive transfusion.The proportion of patients transfused will be compared between the 2 groups.

Detailed Description
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Cardiac surgery represents only a small fraction of all surgical procedures, but consumes a significant proportion of the stored red blood cells (RBC), with almost 50% of patients receiving a perioperative transfusion. Since RBC transfusion is associated with an increased risk of morbidity and mortality, blood patient management strategy has been promoted to favour prevention of anaemia, reduction of bleeding and limitation of transfusion. Current guidelines recommend haemoglobin (Hb) threshold as low as 7 g/dL, but still with a wide possible range (7 to 9 g/dl) and suggest that Hb alone may not be the best criteria for triggering transfusion. As Hb is an oxygen carrier, the rationale for RBC transfusion should be to increase tissue oxygen delivery. Central venous oxygen saturation (central SvO2), which is related to the balance between tissue oxygen delivery and consumption, is easily measurable in cardiac surgery. In a previous study, the investigators showed that in anaemic patients having undergone cardiac surgery, restrictive transfusion according to central SvO2 allowed a significant reduction in RBC transfusion incidence in the ICU. The investigators hypothesize that a restrictive transfusion strategy adjusted by SvO2 during all the perioperative period of cardiac surgery may reduce further the incidence of RBC transfusion. Limiting RBC transfusion to patients with a low SvO2 could save unnecessary transfusions, without increasing the anaemia related risk.

Official Title
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Restrictive Transfusion StratEgy Adjusted by SvO2 During Cardiac Surgery: Multicenter, Single-blinded, Randomised Controlled Trial.

Conditions
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Cardiac Surgery, Cardiopulmonary Bypass

Intervention / Treatment
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* Other: Adjusted Transfusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged above 18 years and under 85 years Signed informed consent form Operated on elective, on-pump cardiac surgery for:Coronary artery bypass graft (CABG); Aortic, mitral or tricuspid valve (replacement or repair); Ascending aorta;Left ventricle assistance device (LVAD) Operated on urgent on-pump cardiac surgery for : CABG;Endocarditis;Aortic dissection; Heart transplantation Subjects must be covered by public health insurance Exclusion Criteria: Patient with no central venous catheter inserted in the superior vena cava Pregnant or breast feeding patient Subject unable to read or/and write Participation in another clinical trial or administration of an unapproved drug within the last 4 weeks before the screening date Medical history of heparin-induced thrombocytopenia contraindicating heparin use during surgery Persons deprived of their liberty by a judicial or administrative decision, persons undergoing psychiatric care and persons admitted to a health or social establishment for purposes other than research

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 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: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Multi-center, single-blinded, and randomized controlled trial.
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Patients assigned to the Control group will be transfused if hemoglobin (Hb) concentration is lower than 7-9 g/d. | |
| Active Comparator: Adjusted transfusion<br>Patients assigned to the SvO2 group will be transfused if Hb concentration is lower than 7-9 g/dL and central SvO2 ≤ 65%. | Other: Adjusted Transfusion<br>* Patients assigned to the SvO2 group will be transfused if Hb concentration is lower than 7-9 g/dL and central SvO2 ≤ 65%. Transfusion will be repeated whenever Hb concentration is lower than 7-9 g/dL and central SvO2 ≤ 65% during surgery and in the ICU (until day 5). Central SvO2 will be measured on a blood sample obtained from the distal lumen of the central venous catheter. Oximetry will be used for measurement with a point-of-care of gas analysis.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| RBC transfusion incidence | Proportion of RBC transfused patients | During cardiac surgery and postoperative ICU stay up to postoperative day 5 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| RBC transfusion incidence during surgery | Proportion of patients transfused with RBC during surgery | During cardiac surgery | 
| RBC units transfused during surgery | Number of RBC units transfused during surgery | During cardiac surgery | 
| RBC transfusion incidence during postoperative ICU stay | Proportions of patients transfused with RBC during postoperative ICU stay | During postoperative ICU stay | 
| RBC units transfused during postoperative ICU stay | Number of RBC units transfused during postoperative stay in ICU | During postoperative ICU stay | 
| RBC transfusion incidence at hospital discharge or day 28 | Proportions of patients transfused with RBC at hospital discharge or day 28 | From cadiac surgery to hospital discharge or day 28 | 
| RBC units transfused at hospital discharge or day 28 | Number of RBC units transfused at hospital discharge or day 28 | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative septic complications | Proportion of postoperative septic complications | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative ischemic complications | Proportion of postoperative ischemic complications (myocardial infarction, stroke, mesenteric) | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative acute kidney injury | Proportion postoperative AKI according to Kdigo stages | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative liver dysfuncion | Proportion of postoperative increase in binirubin or plasma hepatic enzymes | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative respiratory failure | Proportion of postoperative of Pa/Fi<200 | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative low cardiac output syndrome | Proportion of low cardiac output | From cardiac surgery to hospital discharge or day 28 | 
| Postoperative arythmias | Proportion of atrial fibrillation | From cardiac surgery to hospital discharge or day 28 | 
| Length of ICU stay | ICU length of stay (number of days) | From ICU admission to ICU discharge ofr day 28 | 
| Length of hospital stay | Hospital length of stay (number of days) | From ICU admission to hospital discharge or day 28 | 
| Postoperative anemia | Hemoglobin concentration | From ICU admission to hospital discharge or day 28 | 
| Death | Proportion of deaths | From cardiac surgery to hospital discharge or day 28 | 
| Effect of RBC transfusion on Hb | Hb changes after RBC transfusion | During cardiac surgery and postoperative ICU stay up to postoperative day 5 | 
| Effect of RBC transfusion on central SvO2 | Central SvO2 changes after RBC transfusion | During cardiac surgery and postoperative ICU stay up to postoperative day 5 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Blood transfusion, Cardiac surgery