Transfusion Triggers in Cardiac Surgery

Study Overview
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Brief Summary
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A high proportion of patients having cardiac surgery receive red cell transfusions. Yet, the investigators do not know whether transfusions are beneficial and they may be associated with harm. It is thus important to determine when a transfusion is required. The investigators will conduct a small pilot study at St. Michael's Hospital to address this issue. Patients having cardiac surgery will be allocated to one of two transfusion strategies with endpoints being compliance with the transfusion strategy and clinical outcome. The results of this study will be used to design a large definitive multicentered trial of these two transfusion strategies.

Detailed Description
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The optimal hemoglobin concentrations for transfusion in the perioperative setting in patients having cardiac surgery have not been established, and red cell transfusion rates for these patients are high. In a recent retrospective study of seven Canadian centres, which included 11,812 cardiac surgical patients, 44% of patients received one or more red cell units, and the range of patients transfused was 28% to 60%. As morbidity and mortality may be dependent on the severity of anemia and administration of transfusions, it is essential to determine at what hemoglobin concentration physicians should be transfusing these patients, particularly because the efficacy of transfusion has not been established. However, as any definitive trial will require thousands of patients, and as there is variability in transfusion practices, preliminary studies need to be completed to ensure the feasibility of adherence to proposed transfusion strategies. This pilot study is the first of two pilot trials designed to address the question of optimum hemoglobin concentrations for transfusion in patients having cardiac surgery prior to undertaking a definitive randomized controlled trial. The purpose of this study is to determine adherence to transfusion strategies.

Official Title
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Transfusion Triggers in Cardiac Surgery

Conditions
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Cardiac Surgery

Intervention / Treatment
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* Procedure: Transfusion with Red Blood Cells
* Biological: 1 unit of donated red blood cells
* Biological: 1 unit of donated red blood cells


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Care Score of 3/4 or age >/= 80 Signed informed consent Exclusion Criteria: Patients who refuse participation Unable to or refuse blood products Involved in an autologous pre-donation program

Ages Eligible for Study
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Minimum Age: 18 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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1<br>Liberal transfusion strategy | Procedure: Transfusion with Red Blood Cells<br>* Units of donated Red blood cells<br>Biological: 1 unit of donated red blood cells<br>* Units of red blood cells<br>|
| Active Comparator: 2<br>Restrictive transfusion strategy | Biological: 1 unit of donated red blood cells<br>* Units of donated red blood cells<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Overall adherence to the transfusion strategies defined as adherence to the transfusion strategies in 90% of patients in more than 90% of their days in hospital. |  | Day of surgery through to hospital discharge. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 1) enrollment rates 2) proportion of missing data 3) indicators for hypoxemia 4) mean number of red cell units used 5) clinical outcomes |  | Day of surgery through to hospital discharge | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cardiac Surgery, Transfusion Medicine, Cardiac Anesthesia Risk Evaluation (CARE) Score of 3 or 4, (Dupuis J-Y et al, Anesthesiology 2001;94: 194-204)