How is autotransfusion performed?

How to Perform Autotransfusion

Autotransfusion is performed by collecting shed blood from the surgical field, mixing it with anticoagulant during aspiration, processing it through centrifugation and washing with saline, then reinfusing the concentrated red cells back to the patient. 1

Intra-operative Cell Salvage Technique

The most widely recommended method follows this algorithmic approach 1:

Step 1: Blood Collection

• Aspirate shed blood from the surgical field using low-pressure suction
• Mix immediately with anticoagulant as blood is aspirated—either heparinized saline or acid-citrate dextrose
• Blood passes through a filter into a collection reservoir

Step 2: Processing

• Centrifugation separates red cells from whole anticoagulated blood
• Red cells are washed using intravenous saline 0.9%
• Processed cells are pumped into a reinfusion bag
• The end product is the patient's own red cells suspended in saline

Step 3: Reinfusion

• Transfuse the processed blood back to the patient
• Document all volumes collected and reinfused in the patient's case notes 2

Alternative Techniques for Different Settings

Acute Normovolemic Hemodilution (Preoperative)

For elective surgery with expected blood loss >20% total blood volume 2:

1. Collect blood into CPD-A1 anticoagulant packs (450 ml or 250 ml sizes—proper sizing maintains correct anticoagulant ratios)
2. Use a calibrated balance to measure volume drawn
3. Clean skin thoroughly with chlorhexidine in alcohol
4. Clamp donor tubing before removing needle guard to prevent air entry
5. Label immediately with: surname, first names, DOB, hospital number, date/time, responsible medical officer, and "UNTESTED BLOOD: FOR AUTOLOGOUS USE ONLY"
6. Agitate pack gently throughout collection to mix with anticoagulant
7. Seal bleed line with clips or heat sealer at both ends 2

Postoperative Salvage (Unwashed Blood)

• Used primarily after cardiac surgery for mediastinal drainage
• Reinfuse unwashed, filtered blood collected within first 24-48 hours postoperatively
• Simpler and cheaper for low-volume losses but carries theoretical risk of reinfusing activated clotting factors 2

Critical Indications

Use cell salvage when expected blood loss exceeds 500 ml in adults 1, specifically in:

• Cardiac surgery
• Major vascular surgery
• Complex urology
• Obstetric hemorrhage
• Orthopedic surgery

Absolute Contraindications

Do not perform autotransfusion when:

• Bacterial contamination of the surgical wound is present
• Malignant disease (relative contraindication—some centers use with leukocyte depletion filters)
• Sickle cell disease or sickle cell trait (relative) 2

For acute normovolemic hemodilution specifically, avoid in:

• Aortic stenosis
• Unstable angina
• Left main stem disease
• Moderate to severe left ventricular impairment 2

Common Pitfalls and How to Avoid Them

Dilutional coagulopathy: With large volume losses, the washed red cells lack platelets and clotting factors. Monitor coagulation parameters and replace with component therapy (FFP, platelets) as needed 2.

Inadequate anticoagulation: Failure to properly mix blood with anticoagulant during collection leads to clotting in the reservoir. Ensure continuous gentle agitation during collection 2.

Operator training: All cell salvage devices require trained operators. Designate a responsible person for equipment maintenance, adherence to standard operating procedures, and documentation 2.

Hemodynamic instability during hemodilution: Requires adequate monitoring and maintenance of normovolemia to prevent myocardial ischemia in susceptible patients 2.

Equipment Requirements

Cell salvage should be available 24 hours a day in any hospital performing major surgery (excluding minor/day case procedures) 1. Various systems are available—all produce comparable end-products. Centrifugal processors have an excellent long-standing safety record and become increasingly cost-effective with large volume losses 2.