Merck Manual

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Technique of Transfusion


Ravindra Sarode

, MD, The University of Texas Southwestern Medical Center

Reviewed/Revised Feb 2022 | Modified Sep 2022

CAUTION: Before transfusion is started, consent should be obtained, and the patient’s wristband, blood unit label, and compatibility test report must be checked at the bedside to ensure that the blood component is the one intended for the recipient.

Use of an 18-gauge (or larger) needle prevents mechanical damage to and hemolysis of red blood cells. A standard filter should always be used for infusion of any blood component. Only 0.9% saline IV should be allowed into the blood bag or in the same tubing with blood. Hypotonic solutions lyse red blood cells, and the calcium in Ringer’s lactate can cause clotting.

Transfusion of 1 unit of blood or blood component should be completed by 4 hours; longer duration increases the risk of bacterial growth. If transfusion must be given slowly because of heart failure Heart Failure (HF) Heart failure (HF) is a syndrome of ventricular dysfunction. Left ventricular (LV) failure causes shortness of breath and fatigue, and right ventricular (RV) failure causes peripheral and abdominal... read more Heart Failure (HF) or hypervolemia Volume Overload Volume overload generally refers to expansion of the extracellular fluid (ECF) volume. ECF volume expansion typically occurs in heart failure, kidney failure, nephrotic syndrome, and cirrhosis... read more , units may be divided into smaller aliquots in the blood bank. For children, 1 unit of blood can be provided in small sterile aliquots used over several days, thereby minimizing exposure to multiple donors.

Close observation is important, particularly during the first 15 minutes, and includes recording temperature, blood pressure, pulse, and respiratory rate. Periodic observation continues throughout and after the transfusion, during which fluid status is assessed. The patient is kept covered and warm to prevent chills, which may be interpreted as a transfusion reaction.

Elective transfusions at night are discouraged.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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