Sequestration of Platelets Prior to Bypass Reduces Bleeding After Cardiac Surgery

NCT ID: NCT00359398

Last Updated: 2016-04-14

Basic Information

• Recruitment Status: TERMINATED
• Clinical Phase: PHASE2
• Total Enrollment: 30 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2006-08-31
• Study Completion Date: 2009-07-31

Brief Summary

Excessive bleeding is common after cardiac surgery. This may result in patients receiving a blood transfusion or suffering the life-threatening complication of cardiac tamponade. Tamponade is when excessive bleeding compresses the heart and prevents it from pumping properly. A major reason for the bleeding is the damage done to platelets by the cardiopulmonary bypass (CPB) machine. Often patients receive platelets and plasma from blood donors to try to reduce the bleeding post-operatively. The investigators plan to take platelets and plasma from patients before they are damaged. They would then return these 'undamaged' sequestered platelets to the patients after the bypass machine is no longer needed. Therefore, the investigators' primary question is whether platelet sequestration would reduce the bleeding problems that occur following cardiac surgery. They will evaluate bleeding problems using thromboelastography, which provides a comprehensive assessment of both how blood clots form and their strength. If sequestration reduces bleeding problems following cardiac surgery then it may reduce the chance of patients receiving blood products from donors. Although donated blood is thoroughly tested, its use does expose patients to the risk of transfusion errors, blood borne infections and reactions. Avoiding its use would be very desirable.

Detailed Description

Hypothesis:

Patients undergoing repeat median sternotomy or requiring prolonged cardiopulmonary bypass (CPB) often develop a coagulopathy at the end of surgery. We propose sequestering plasma and platelets from these patients prior to CPB and thus prior to the dilution and platelet damage that occurs with CPB. We hypothesise that if these plasma and platelets are stored properly during CPB, and administered at the end of the operation, they will reduce any coagulopathy and the associated bleeding.

Study population:

Patients undergoing repeat median sternotomy, mitral valve repair, double valve operations, aortic surgery, or combined valve and coronary artery surgery.

Exclusion criteria will include those with anaemia, thrombocytopenia, unstable angina, anti-platelet therapy within the previous seven days, known or symptomatic cerebrovascular disease, known disorders of haemostasis, aprotinin sensitivity and pregnancy.

Intervention:

Patients will be randomised by a closed envelope technique to receive platelet/plasma sequestration or not. Patients randomised to undergo sequestration will have 14 mL/Kg blood taken. The blood will be separated into red cells and platelets/plasma. Anaemia would be prevented by returning the processed red blood cells to the patient. We will store platelets at 20-24°C/room temperature on a platelet rocker according to guidelines from the National Blood Service.

Assessment of coagulation:

Patients' coagulation status will be evaluated before and after surgery. Four methods will be employed to comprehensively assess the coagulation system: platelet counts and conventional clotting studies; heparin levels; thromboelastography; and platelet function analyser.

Conditions

Cardiac Surgical Procedures; Cardiopulmonary Bypass; Blood Platelet Disorders; Blood Coagulation Disorders

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: SINGLE

Study Groups

Platelet sequestration

Sequestration of platelet rich plasma before cardiopulmonary bypass

Group Type: EXPERIMENTAL

Platelet rich plasma sequestration

Intervention Type: PROCEDURE

Venesection of blood (14 ml/kg) and separation to red cells and platelet rich plasma.

Standard care

No platelet rich plasma sequestration undertaken before cardiopulmonary bypass (usual practice)

Group Type: NO_INTERVENTION

No interventions assigned to this group

Interventions

Platelet rich plasma sequestration

Venesection of blood (14 ml/kg) and separation to red cells and platelet rich plasma.

Intervention Type: PROCEDURE

Other Intervention Names

Haemonetics cell salavage system

Eligibility Criteria

Inclusion Criteria

Adult patients undergoing cardiac surgery that involves:

• Repeat median sternotomy
• Mitral valve repair
• Double valve operations
• Combined valve and coronary surgery
• Anticipated prolonged cardiopulmonary bypass

Exclusion Criteria

• Pre-operative anaemia
• Pre-operative thrombocytopenia
• Unstable angina
• Anti-platelet therapy (e.g. aspirin, clopidogrel) within the previous 7 days
• Known or symptomatic cerebrovascular disease
• Known disorders of haemostasis
• Aprotinin sensitivity
• Pregnancy.

• Minimum Eligible Age: 16 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Royal Brompton & Harefield NHS Foundation Trust

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Simon J Finney, MBChB, PhD

Role: PRINCIPAL_INVESTIGATOR

Royal Brompton & Harefield NHS Foundation Trust

Andrea Kelleher, MBBS

Role: PRINCIPAL_INVESTIGATOR

Royal Brompton & Harefield NHS Foundation Trust

Judith Hall

Role: PRINCIPAL_INVESTIGATOR

Royal Brompton & Harefield NHS Foundation Trust

Simon Davidson, PhD

Role: PRINCIPAL_INVESTIGATOR

Royal Brompton & Harefield NHS Foundation Trust

Locations

Royal Brompton Hospital

London, , United Kingdom

Countries

United Kingdom

Other Identifiers

2006IC003B

Identifier Type: -

Identifier Source: org_study_id