Intraoperative blood salvage is a type of autotransfusion or transfusing patient’s own blood instead of allogenic blood retrieved from blood donors.
It is also known as autologous blood transfusion or cell salvage.
It is a medical procedure involving recovering blood lost during surgery and reinfusing it into the patient.
In other words, the blood that is shed during is retrieved, processed, and returned to the patient.
Other terms for intraoperative blood salvage are intraoperative autologous transfusion, intraoperative salvage, or intraoperative autotransfusion.
Intraoperative blood salvage provides immense quantities of patient’s own blood [autologous blood] very rapidly.
It reduced the need for allogenic blood transfusions and the risk of transmission of infections.
The concept of intraoperative blood salvage was suggested way back in 1874 when James Highmore proposed the use of autotransfusion and emphasized that patient’s own shed blood was an overlooked source which could be used to great advantage.
The first commercially available instrument that could concentrate and wash salvaged red cells was the Cell Saver (Haemonetics, Braintree, MA), introduced in 1974.
Virtually all similar intraoperative blood salvage instruments are referred to as “cell savers”.
Intraoperative blood salvage is widely used during cardiac surgery, non-infected major joint revision arthroplasty, scoliosis surgery, vascular surgery, major urological procedures, and trauma surgery.
Indications for Intraoperative Blood Salvage
Intraoperative blood salvage can be considered in a patient when the anticipated loss is greater than 20 percent of the blood volume.
Contraindications for Intraoperative Blood Salvage
- Patient refuses the procedure
- Contamination of the surgical field with feces, urine or amniotic fluid
- The presence of infection in the operative field
- The presence in the operative field of malignant tumors
- Patients with red cell disorders like sickle cell anemia
- Avoid using procedure when the surgical field contains
- Betadine / Chlorhexidine
- Hydrogen peroxide
- Distilled water
- Antibiotics not for parenteral use
- Fibrin adhesives
Types of Intraoperative Blood Salvage – Blood Salvage Techniques
three types of salvage procedures are known
- Cell Savers or cell processors
- Direct transfusion
- Ultrafiltration of whole blood
Cell Saver Technique
After the blood is collected from the surgical field, it is mixed with anticoagulant. The aspirated blood is collected in a reservoir until there is sufficient blood for processing.
When sufficient quantity is reached, the salvaged blood is pumped into the centrifuge bowl, where it is concentrated and then washed with an isotonic electrolyte solution, most often saline.
The processed red cell suspension is then pumped from the centrifuge bowl into an infusion bag.
Modern cell salvage instruments can process a full reservoir of blood, and provide 225 mL of washed, saline-suspended red cells with a hematocrit of 50 percent or more in approximately three minutes.
Thus, a massively bleeding patient can be provided with the equivalent of 12 units of banked blood per hour, all from his own blood.
- Air embolism
- Coagulation disorders
- Leukocyte activation with resulting lung damage
- Dissemination of microaggregates, infectious matter, cytokines, and malignant cells
Direct transfusion is a blood salvaging method associated with cardiopulmonary bypass circuits or other extracorporeal circuits that are used in surgery such as coronary artery bypass grafts, valve replacement, or surgical repair of the great vessels.
Following these surgeries, extracorporeal circuits contain a significant volume of diluted whole blood that can be harvested in transfer bags and re-infused into patients. As this residual blood is quite dilute, a diuretic is needed in addition.
Ultrafiltration devices filter the patient’s anticoagulated whole blood to remove unwanted excess elements and make concentrated whole blood available for reinfusion.
These are not as good as cell savers in the removal of potentially harmful contaminants but reduce contaminants enough.
Other Methods to Reduce Need for Allogenic Blood Transfusion
There are some other methods which can be employed to reduce the need for allogeneic transfusions of blood
Minimally Invasive Surgery
By using minimally invasive procedures, the blood loss decreases and therefore the need for transfusion is reduced. For example, a closed nailing of femur hardly results in blood loss whereas open nailing which involves exposure of fracture by cutting the tissue is associated with greater blood loss.
Erythropoietin is a hormone that stimulates peripheral stem cells in the bone marrow to produce red blood cells. This results in higher hemoglobin levels in patient and thus offsetting the blood loss during surgery
Blood volume expanders and oxygen carriers.
Preoperative Autologous Blood Donation
This includes pre-operative bleeding of the patient for a donation for self. That blood unit is used for transfusion during surgery to compensate for the blood loss.
Instead, someone else as being the donor and patient being the recipient, in this method, the patient himself is donor and recipient.
The drawback of this method is that it could only be applied in scheduled surgeries and once the blood has been donated, the surgery needs to be done before the expiry of the donated blood which equates with in vitro life of red blood cells, 35 days.