Direct and exchange blood transfusion

Direct transfusion: core concepts and indications

Although indirect transfusion of preserved blood remains the primary clinical method, direct transfusion is used in rare cases. This is the immediate transfer of blood from a donor to a recipient.

The procedure is performed under strict indications when preserved blood is ineffective:

• Hemophilia accompanied by prolonged bleeding that is refractory to standard hemostatic therapy.
• Severe coagulation disorders, such as acute fibrinolysis, afibrinogenemia, or thrombocytopenia (especially in blood system disorders or following previous massive blood transfusions).
• Stage III traumatic shock associated with acute blood loss exceeding 25–50% of the circulating blood volume (CBV).

Algorithm and technique of direct transfusion

The donor undergoes preliminary screening at the blood transfusion station. However, the physician performs the essential safety checks directly at the patient's bedside prior to the procedure. These include determining the blood group and Rh factor of both participants, as well as performing compatibility tests for these parameters.

The classical syringe method requires 20 to 40 syringes of 20 mL capacity, venipuncture needles with rubber tubing, Billroth clamps, and sterile gauze balls. The procedure is performed through synchronized actions of the physician and the nurse:

1. The nurse draws blood from the donor's vein into the syringe.
2. Quickly clamps the rubber tubing to prevent blood loss.
3. Passes the filled syringe to the physician.
4. The physician immediately administers the fresh blood into the patient's vein.

Features of the biological test: The biological test is performed at the very beginning of the transfusion. Before drawing donor blood, 2 mL of a 4% sodium citrate solution is drawn into the first three syringes. This is necessary to prevent clotting, as the blood from these first syringes is injected very slowly — at a rate of one syringe per 2 minutes. If no adverse reactions occur, the team proceeds to rapid administration.

Note: An alternative to the syringe method is the use of special hardware systems for direct transfusion.

Exchange blood transfusion

This method involves partial or complete exfusion (removal) of blood from the patient's vascular bed with simultaneous replacement of the lost volume using donor blood or blood substitutes. Freshly preserved blood or preserved blood with a short storage life is used for the procedure.

Main indications:

• Severe poisoning (for the removal of poisons and toxins circulating in the bloodstream).
• Hemolytic disease of the newborn.
• Transfusion reaction shock.
• Acute renal failure.

Technique: The most critical rule is that removal and infusion must occur strictly simultaneously.

• Infusion is usually performed into any available superficial vein.
• Exfusion (removal) is performed from large veins or arteries, which prevents blood clotting during a prolonged procedure.

The exchange rate is approximately 1000 mL per 15–20 minutes. Complete replacement of the patient's total blood volume may require a colossal amount of donor material — from 10 to 15 liters.

Briefly: answers to topical questions

Class and exam questions

What else to study on this topic

• Transfusion of preserved blood (indirect transfusion)
• Autologous blood transfusion: collection and transfusion of own blood
• Transfusion shock: pathogenesis and management algorithm
• Acute fibrinolysis and DIC syndrome in surgery
• Hemolytic disease of the newborn: indications for exchange transfusion

Other topics in the section "CHAPTER 6. BLOOD TRANSFUSION"

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