Autologous blood transfusion

This involves transfusion of the patient's own blood that has been obtained either long before surgery, immediately before or during surgery. Autologous blood transfusion is void of all disadvantages that transfusion of donor's blood may have, such as immunisation of the recipient, development of homological blood syndrome, and, apart from these, it eliminates the problem of finding individual donors for patients with antibodies to red blood cell antigens that are not included in the ABO and Rh systems.

The indications for autologous blood transfusion are as follows:

1) rare blood group of the patient;

2) inability to find a donor;

3) increased risk of a post-transfusion reaction;

4) impending operation associated with a massive blood loss.

Autologous transfusion is contraindicated in

1) infections;

2) severe liver or kidney diseases;

3) debilitating malady (e.g. full-blown tumours).

The widely known method is blood salvage, or retransfusion of the blood lost and collected during or after surgery. It is applied in such abdominal conditions as ectopic gestation, rupture of the spleen, liver or mesenteric vessels; in closed damage to the chest organs - injuries to the intrathoracic vessels and the lung. Reinfusion is effectively used for blood replacement during operations when the patient's blood from the wound is collected and reinfused. Blood collected into a bottle with anticoagulant is filtered through 8-layer gauze and emptied into the transfusion system equipped with a standard micro-filter for onward blood transfusion. Blood salvage is contraindicated if there is a damage to any hollow organ of the chest (the major bronchi, oesophagus) and the abdominal cavity (the stomach, intestine, gallbladder, extra-hepatic bile ducts, and urinary bladder) as well as in malignant tumours. Also, retransfusion of the blood that has stayed in the abdominal cavity for more than 24 hours should be avoided. Reinfusion is contraindicated when the accumulated blood is contaminated with pus, stomach and intestinal contents, bleeding from a ruptured uterus and malignant tumours.

To preserve the blood, preservative solutions in their ratio to blood of 1: 4, or most often heparin solution is used - 10 mg of heparin in 50 mL of normal saline is mixed with 500 ml of blood. The accumulated blood is collected by scooping dry with a small metallic cup and immediately filtered through an 8-layer gauze. Collecting blood by a suction machine with a pressure of at least 0, 2 atmospheres is more effective. Blood collected into a bottle with anticoagulant is filtered through 8-layer gauze and emptied into the transfusion system equipped with a standard filter for onward blood transfusion.

Autotransfusion, using previously preserved blood, is done by draining the patient about 4-6 days before scheduled surgery and storing the blood for later use. Four to six days is enough for the patient to regain their lost blood, the stored blood being intact with all the valuable components. The process of recovery after the donation is facilitated by not only the transfer of interstitial fluid into the blood stream (like is the case in any blood loss), but also by the stimulatory effect of blood drainage on haemopoiesis. Preparing blood through that way yields a volume of as great as 500 ml. When blood is collected in steps within a long-term preoperative period, as much as 1, 000 ml can be preserved within 15 days or even 1, 500 ml within 25 days. If this method is to be used, the blood volume of 300-400 ml first is drained, it is then reinfused every 4-5 days and 200-250 ml more than what has been given are drained. Such method provides a large amount of good quality blood that can be stored for maximum 4-5 days.

Blood is collected into bottles with preservatives and stored at 4 °C. To be able to keep blood for a long time it has to be frozen at -196 °C.

Haemodilution is another method of autologous blood transfusion. Urgent preoperative haemodilution is done immediately prior to the surgery and is aimed at reducing bleeding during the intervention. As a result, the patient loses the diluted blood (with limited amounts of blood cells and plasma factors); and replacement of blood loss by auto-blood follows. Immediately prior to operation the patient's blood is drawn into a bottle containing some preservative and at the same time the haemodilution solution consisting of rheopolyglukin, 20% albumin and Ringer-Lock's solution is given. In mild haemodilution (i.e. a reduction in haematocrit by a fourth) the volume of blood drained should approximate 800 ml, the volume of infusion given - 1, 100-1, 200 ml (rheopolyglukin - 400 ml, Ringer's solution - 500 ml, 20% albumin - 100 ml). Significant haemodilution (i.e. a reduction in haematocrit by one-third) involves drainage of about 1, 200 ml, infusion of about 1600 ml (rheopolyglukin - 700 ml, Ringer's solution - 750 ml, 20% albumin - 150 ml).

Haemodilution aimed at reducing the amount of blood lost at operation does not necessarily involve drainage the patient's blood. This can be achieved by infusing solutions with high colloid properties, that can increase the circulating blood volume (e.g. albumin, polyglukin, gelatinol) in combination with blood replacement solutions (Ringer's solution).

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