A blood transfusion is a controlled medical procedure used to deliver donated blood components directly into a patient’s circulatory system. This intervention is often necessary to restore blood volume following significant blood loss, correct severe anemia, or replace specific components like platelets or clotting factors. Because this process involves introducing foreign material into the body, it is governed by strict protocols to ensure patient safety and prevent complications. Successfully administering blood requires meticulous attention to detail at every stage, from initial verification to post-infusion monitoring.
Essential Pre-Transfusion Verification
Before the blood product is brought to the patient’s bedside, a physician’s order and documented patient consent must be confirmed. The blood component should be retrieved from the blood bank no more than 30 minutes before the transfusion begins to maintain its quality. The most critical safety step is the final identification verification, which requires a “two-person check” at the patient’s bedside to prevent fatal errors.
The two healthcare professionals must visually and verbally confirm that the patient’s identification (ID) band matches the information on the blood bank tag and the blood product label. This triple-check must ensure that the patient’s full name, date of birth, and unique identification number are identical across all three sources. Verification also confirms that the blood product’s ABO and Rh type matches the patient’s required type and that the expiration date has not been exceeded.
If the patient is conscious, they are asked to state their name and date of birth, actively participating in the check. For patients unable to communicate, the ID band details are verified against the medical record and the blood component tag by the two staff members. This independent double-check procedure is designed to catch human error, which is the primary cause of incompatible transfusions.
Assembling the Transfusion Equipment
Preparing the physical equipment is the next step after the essential verification is complete, focusing on maintaining the integrity of the blood component. The transfusion must be administered using a specialized blood administration set, which is a Y-type tubing that includes an in-line filter. This filter, typically having a pore size between 170 and 260 micrometers, removes any small clots or cellular aggregates that may have formed during storage.
The tubing must first be primed with 0.9% sodium chloride, commonly known as normal saline, which is the only solution compatible with blood products. Normal saline is an isotonic solution, meaning it has the same osmotic pressure as the patient’s blood plasma. Other intravenous solutions, such as those containing dextrose or Ringer’s lactate, can cause the red blood cells to swell and rupture (hemolysis) or clot due to the presence of calcium.
To begin the preparation, one arm of the Y-tubing is spiked into the bag of normal saline, and the other arm is spiked into the blood component bag, such as packed red blood cells. The saline line is then opened to flush the tubing, pushing the air out and filling the entire line and the drip chamber with the isotonic solution before the blood is introduced. The blood product itself is visually inspected for any signs of discoloration, gas bubbles, or clumping before it is spiked and allowed to flow into the primed tubing.
Initiating the Infusion and Monitoring Start-Up
Once the equipment is prepared and the line is primed, the final steps at the bedside involve connecting the line and carefully starting the flow. Immediately before connecting the blood line, the patient’s baseline vital signs—including temperature, heart rate, blood pressure, and respiratory rate—must be measured and recorded. This provides a clear comparison point should any adverse change occur during the transfusion.
The primed blood line is connected to the patient’s established intravenous access, preferably an 18- to 20-gauge catheter for optimal flow. The infusion is then started at a very slow rate, typically around 50 milliliters per hour for adults, for the first 15 minutes. This slow initial rate is a safety measure because the most severe and immediate transfusion reactions generally occur within this timeframe, often after only a small volume of blood has been infused.
The healthcare professional must remain at the bedside for this entire 15-minute period to closely observe the patient for any subtle signs of a reaction. If the patient shows no signs of an adverse reaction after this initial period, another set of vital signs is taken and recorded. If tolerated, the infusion rate can then be increased to the prescribed rate, ensuring that the entire unit of blood is transfused within a maximum of four hours to prevent bacterial proliferation.
Identifying and Managing Adverse Reactions
Even with strict adherence to pre-transfusion protocols, adverse reactions can occur, making continuous monitoring throughout the process mandatory. Acute transfusion reactions can manifest rapidly and range from mild symptoms like a rash or itching to life-threatening signs such as fever, chills, back pain, shortness of breath, and a sudden drop in blood pressure. The patient should be educated to report any feeling of “something being wrong” or a sudden onset of symptoms.
If a transfusion reaction is suspected, the immediate action is to stop the transfusion instantly without hesitation. The intravenous line must be kept open, but only with the normal saline solution used to prime the line, ensuring that a patent access route remains for administering emergency medications. It is important not to flush the blood remaining in the administration set into the patient.
After stopping the infusion, the patient’s airway, breathing, and circulation are immediately assessed, and emergency procedures are activated if the reaction is severe. The physician and the blood bank must be notified immediately. The entire transfusion setup—the blood bag, the administration set, and any remaining saline—is often sent back to the laboratory for investigation, and the healthcare provider must re-verify the patient and blood unit identification to rule out a clerical error.