8.2 Blood Transfusion Practice, Crossmatching & Transfusion Reactions

8.2 Blood Transfusion Practice, Crossmatching & Transfusion Reactions

Quick Answer: Safe blood transfusion therapy requires meticulous compliance with verification, administration, and monitoring standards. Transfusing nurses must perform a rigorous dual-nurse bedside check of the patient's identity and unit compatibility. Transfusions must be initiated within 30 minutes of removing blood from the blood bank refrigerator and completed within 4 hours. Only 0.9% Normal Saline is compatible with red blood cells; dextrose causes hemolysis, and Ringer's lactate causes in-line coagulation. During the first 15 minutes, infuse slowly (about 2 mL per minute or less) while remaining at the bedside. If a reaction occurs, immediately stop the transfusion, disconnect the set, keep the vein open with normal saline using new tubing, notify the physician and blood bank, monitor vitals, and send the implicated unit and patient samples for laboratory investigation.

---

Immunohematology: ABO and Rhesus Blood Group Systems

Blood transfusion safety rests on the biological compatibility of donor erythrocyte antigens with recipient plasma antibodies. Administering antigen-positive blood to an individual possessing corresponding antibodies triggers rapid, complement-mediated intravascular destruction of the transfused cells.

The ABO Blood Group System

The ABO system is determined by carbohydrate antigens (A and B) expressed on erythrocyte membranes, governed by alleles on chromosome 9. Individuals naturally synthesize circulating IgM isohemagglutinins (antibodies) against the antigens absent from their own erythrocytes:

• Group A: Has A antigens on erythrocytes; possesses anti-B antibodies in plasma.
• Group B: Has B antigens on erythrocytes; possesses anti-A antibodies in plasma.
• Group AB: Has both A and B antigens on erythrocytes; possesses neither anti-A nor anti-B antibodies in plasma. Known as the universal red cell recipient.
• Group O: Lacks A and B antigens on erythrocytes; possesses both anti-A and anti-B antibodies in plasma. Group O red cells will not be lysed by recipient ABO antibodies, making Group O negative the universal red cell donor for emergency un-crossmatched resuscitation.

The Rhesus (Rh) Blood Group System

The Rh system involves protein antigens on the red cell membrane, of which the D antigen is the most clinically immunogenic:

• Rh-Positive ($Rh^+$): Expresses the D antigen (accounts for approximately 95% of individuals in Ghana).
• Rh-Negative ($Rh^-$): Lacks the D antigen (approximately 5% of Ghanaians). Rh-negative individuals do not naturally possess anti-D antibodies; however, exposure to Rh-positive blood via transfusion or feto-maternal hemorrhage during childbirth stimulates IgG anti-D alloimmunization. Subsequent exposure causes severe hemolytic transfusion reactions or hemolytic disease of the fetus and newborn (erythroblastosis fetalis).

---

Blood Components: Indications, Dosing & Storage Benchmarks

Modern transfusion medicine emphasizes targeted component therapy rather than routine whole blood transfusion, ensuring optimal resource utilization and minimizing circulatory overload.

---

Pre-Transfusion Nursing Protocol: Verification & Patient Safety

Transfusion errors are almost entirely preventable human errors resulting from failure to adhere to standardized identification protocols.

1. Physician Orders and Informed Consent

• Verify a clear, written medical prescription specifying the component type, volume/number of units, specific rate or duration, and any required premedications (e.g., furosemide, antihistamines).
• Confirm that informed written consent has been obtained and documented by the physician, having explained benefits, risks, and alternatives to the patient.

2. Blood Grouping and Crossmatching

• Type and Screen: Confirms the patient's ABO and Rh group and screens for unexpected red cell alloantibodies.
• Major Crossmatch: The laboratory mixes donor red cells with recipient serum. Absence of agglutination or hemolysis confirms compatibility.
• Phlebotomy Safety: The pre-transfusion blood sample must be labeled immediately at the patient's bedside after verifying identity with the patient. Never pre-label collection tubes.

3. Dual-Nurse Bedside Verification Checklist

Immediately prior to spiking the blood bag, two qualified registered nurses must independently, concurrently verify all information at the patient's bedside:

1. Patient Full Legal Name and Hospital Identification Number (Folder Number) matched across the patient's identification wristband, the medical chart, and the laboratory crossmatch compatibility tag.
2. Patient's Verified Blood Group and Rh Type matches the crossmatch compatibility report.
3. Donor Blood Unit Serial Number printed on the blood bag matches the unit number listed on the crossmatch form.
4. ABO and Rh Group of the Donor Unit is compatible with the recipient.
5. Expiration Date and Time on the blood container has not passed.
6. Physical Inspection of the Unit: Inspect for dark purple or black discoloration (bacterial contamination), gas bubbles (microbial growth), gross clots (fibrin formation), or purple cloudiness/turbidity (hemolysis). If any irregularity is observed, quarantine the bag and return it immediately to the blood bank.

---

Administration Technique and Intravenous Compatibility

Cannula Sizing and Specialized Administration Tubing

• Intravenous Cannula Gauge: Use a large-bore cannula—18-gauge or 20-gauge in adults—to prevent mechanical sheer stress and hemolysis of fragile red cells during infusion. A 22-gauge cannula may be utilized in pediatric patients or adults with fragile peripheral veins, recognizing that infusion flow rates will be slower.
• Dedicated Blood Administration Set: Blood must be infused through a dedicated administration set incorporating an in-line microaggregate filter (170 to 200 microns). The filter traps fibrin strands, cellular debris, and microthrombi generated during storage. Tubing must be changed after every 2 units or after 4 hours of use to prevent bacterial seeding.

Strict Intravenous Fluid Compatibility: The 0.9% Normal Saline Rule

Only 0.9% Normal Saline (Isotonic Sodium Chloride) is compatible with blood components. No other intravenous fluid or medication may ever be piggybacked, added to, or co-infused through the same administration line:

• Dextrose Solutions (e.g., 5% D/W, D5 1/2 NS): Strictly contraindicated! Dextrose solutions are hypotonic relative to intracellular erythrocyte contents. When exposed, red blood cells rapidly absorb water, swell, clump, and undergo in-line osmotic hemolysis, infusing hemolyzed ghost cells and free hemoglobin directly into the recipient.
• Ringer's Lactate / Hartmann's Solution: Strictly contraindicated! Ringer's lactate contains ionized calcium ($Ca^{2+}$). Blood units are preserved with citrate, an anticoagulant that binds ionized calcium to prevent clotting in the bag. Infusing calcium-containing solutions overwhelms the citrate buffer, neutralizing its anticoagulant capacity and triggering intravascular and intraluminal clot formation that can occlude the line or embolize.
• Medications: Never inject any pharmacological agents into a running blood line. If medications are required during transfusion, establish a separate secondary IV access site.

---

Infusion Timelines and Vital Sign Monitoring Protocols

The 30-Minute and 4-Hour Rules

1. Initiate within 30 Minutes: Blood components must be spiked and the transfusion initiated within 30 minutes of release from blood bank refrigeration. If transfusion cannot be commenced within this window, the unit must be returned immediately to the blood bank. Units left at room temperature for $>30$ minutes cannot be re-refrigerated and must be discarded.
2. Complete within 4 Hours: The entire transfusion of a unit of PRBCs or whole blood must be completed within 4 hours from the time of issue. Prolonged hanging at ambient ward temperatures creates an ideal culture medium for proliferated psychrophilic and skin-contaminating bacteria, greatly increasing the risk of lethal septic shock.

The Critical First 15-Minute Observation Window

The most acute, fatal immunological reactions (such as ABO-incompatible hemolytic shock or anaphylaxis) manifest within the first 15 minutes of exposure:

• Initial Flow Rate: Run the transfusion slowly—about 2 mL per minute or less—for the first 15 minutes (roughly 30 mL of blood). Convert this to drops per minute with the drop factor printed on the blood giving set (e.g., a 15 drops/mL set at 2 mL/min gives 30 drops/min).
• Bedside Presence: The registered nurse must remain physically at the patient's bedside for the entire first 15 minutes, directly observing for subtle complaints of discomfort, chest tightness, dyspnea, chills, flushing, or back pain.
• Monitoring Schedule:
  • Obtain a full baseline set of vital signs (temperature, pulse, BP, respiratory rate, $\text{SpO}_2$) within 15 minutes prior to spiking the unit.
  • Repeat vital signs at 15 minutes after blood enters the vein.
  • If vitals remain stable and the patient is asymptomatic, advance the flow rate to the medically prescribed velocity (typically 2 to 3 hours total per unit).
  • Record vital signs at 30 minutes, hourly thereafter until completion, and one hour post-transfusion.

---

Clinical Spectrum of Transfusion Reactions

Transfusion reactions are classified into acute (occurring during or within 24 hours of transfusion) and delayed complications:

                         ACUTE TRANSFUSION REACTIONS
                                      |
        +-----------------+-----------+-----------+-----------------+
        |                 |                       |                 |
        v                 v                       v                 v
 Acute Hemolytic    Febrile Non-              Allergic /        Volume Overload
   (ABO Mismatch)     Hemolytic (FNHTR)       Anaphylactic         (TACO)
        |                 |                       |                 |
  * Flank/Back pain * Temp rise >= 1°C      * Urticaria/Hives * Dyspnea & Crackles
  * Fever & Chills  * Shivering/Chills      * Pruritus        * Hypertension & JVD
  * Hypotension     * Stable hemodynamics   * Stridor/Wheeze  * S3 gallop
  * Red/Dark urine  * Cytokine-mediated     * IgA deficiency  * Treat: Furosemide,
  * Shock & DIC     * Treat: Paracetamol      shock             upright posture

1. Acute Hemolytic Transfusion Reaction (AHTR)

• Pathophysiology: Caused by ABO or major red cell antigen incompatibility. Pre-existing recipient antibodies bind donor red cell antigens, triggering complement cascade activation, fulminant intravascular hemolysis, release of vasoactive substances, and generation of procoagulant tissue factor.
• Clinical Manifestations: Sudden onset of severe lumbar/flank pain, substernal chest tightness, burning sensation along the infusion vein, high fever, rigors, tachycardia, profound hypotension, hemoglobinuria ("port-wine" or dark reddish-brown urine), and progression into Disseminated Intravascular Coagulation (DIC) and acute oliguric renal failure.

2. Febrile Non-Hemolytic Transfusion Reaction (FNHTR)

• Pathophysiology: The most frequent transfusion reaction. Caused by recipient antibodies directed against donor leukocytes or accumulation of pro-inflammatory cytokines (IL-1, IL-6, TNF-alpha) released from white cells during storage.
• Manifestations: Temperature rise of $\ge 1^\circ\text{C}$ ($1.8^\circ\text{F}$) above baseline, accompanied by chills, shivering, headache, and flushing, in the absence of hemolysis or hypotension.
• Management: Stop transfusion, verify absence of hemolysis. Administer paracetamol (avoid aspirin in thrombocytopenia). Prevent in future transfusions using leukocyte-depleted (leukoreduced) blood components.

3. Allergic and Anaphylactic Reactions

• Pathophysiology: Hypersensitivity response to foreign soluble plasma proteins in donor blood. Mild allergic reactions are IgE-mediated histamine releases. Anaphylactic reactions occur classically in IgA-deficient patients who have anti-IgA antibodies reacting to donor IgA.
• Manifestations: Mild presents with generalized pruritus, urticaria (hives), and flushing. Anaphylaxis presents immediately with stridor, bronchospasm, severe wheezing, laryngeal angioedema, facial swelling, abdominal cramps, hypotension, and circulatory collapse without fever.
• Management: For mild hives without systemic symptoms, temporarily hold transfusion, administer oral/parenteral antihistamine (e.g., chlorpheniramine), and resume slowly if resolved. For anaphylaxis: stop immediately, administer intramuscular adrenaline (epinephrine 1:1000, 0.3–0.5 mg IM) into anterolateral thigh, support airway, deliver high-flow oxygen, and administer IV fluids and corticosteroids.

4. Transfusion-Associated Circulatory Overload (TACO)

• Pathophysiology: Non-cardiogenic or cardiogenic acute pulmonary edema resulting from excessively rapid or voluminous blood component administration beyond the cardiovascular system's reserve. High-risk groups include elderly patients, chronic renal disease, and pre-existing heart failure.
• Manifestations: Acute dyspnea, orthopnea, cyanosis, tachypnea, tachycardia, severe hypertension, jugular venous distension (JVD), bibasilar pulmonary crackles, and an $S_3$ gallop occurring during or within 6 hours of transfusion.
• Management: Immediately stop the transfusion. Position the patient upright with legs dangling over the bed (reduces preload), administer high-flow oxygen, and administer intravenous loop diuretics (furosemide 20–40 mg IV).

5. Transfusion-Related Acute Lung Injury (TRALI)

• Pathophysiology: Leading cause of transfusion-related fatality in developed health systems. Mediated by donor antibodies (anti-HLA or anti-HNA) that activate recipient neutrophils sequestered in pulmonary microvasculature, causing capillary endothelial breakdown and non-cardiogenic alveolar edema.
• Manifestations: Sudden hypoxemic respiratory failure within 6 hours of transfusion, bilateral non-cardiogenic pulmonary infiltrates on CXR ("white-out"), hypotension, fever, with normal jugular venous pressure (distinguishing it from TACO).
• Management: Stop transfusion immediately; manage with aggressive ventilatory support and hemodynamic stabilization. Avoid diuretics as patients are often normovolemic or hypotensive.

---

Emergency Nursing Protocol: Step-by-Step Response to Reactions

If any signs of an adverse transfusion reaction emerge, the nurse must immediately execute the following six-step emergency protocol:

                               TRANSFUSION REACTION OCCURS
                                            |
                                            v
                      +------------------------------------------+
                      | 1. STOP THE TRANSFUSION IMMEDIATELY      |
                      +------------------------------------------+
                                            |
                                            v
                      +------------------------------------------+
                      | 2. DISCONNECT BLOOD SET & KVO WITH       |
                      |    NORMAL SALINE USING NEW STERILE TUBING|
                      +------------------------------------------+
                                            |
                                            v
                      +------------------------------------------+
                      | 3. NOTIFY ATTENDING DOCTOR & BLOOD BANK  |
                      +------------------------------------------+
                                            |
                                            v
                      +------------------------------------------+
                      | 4. ASSESS VITALS, MAINTAIN ABCs &        |
                      |    PREPARE EMERGENCY PHARMACOTHERAPY     |
                      +------------------------------------------+
                                            |
                                            v
                      +------------------------------------------+
                      | 5. COLLECT & DESPATCH BLOOD/URINE LAB    |
                      |    SPECIMENS WITH IMPLICATED UNIT & TUBING|
                      +------------------------------------------+
                                            |
                                            v
                      +------------------------------------------+
                      | 6. DOCUMENT THOROUGHLY IN MEDICAL RECORD |
                      +------------------------------------------+

1. STOP THE TRANSFUSION IMMEDIATELY: Cease flow instantly. Do not allow another drop to enter the patient.
2. DISCONNECT AND MAINTAIN ACCESS: Disconnect the blood administration set from the IV cannula hub. Never flush residual blood from the tubing into the patient! Attach a completely new sterile IV set primed with 0.9% Normal Saline and run at a keep-vein-open (KVO) rate to preserve emergency venous access.
3. NOTIFY PHYSICIAN AND BLOOD BANK: Summon the attending physician to the bedside and notify the blood bank laboratory that an acute reaction is underway.
4. ASSESS AND SUPPORT ABCs: Recheck full vital signs every 5 minutes. Deliver supplemental high-flow oxygen, maintain airway patency, and prepare emergency pharmacotherapy (adrenaline, antihistamines, hydrocortisone, dopamine, or furosemide as clinically indicated).
5. DESPATCH SAMPLES AND UNIT: Package the remaining blood unit, attached infusion set, and IV solution. Collect fresh post-transfusion venous blood samples (for repeat crossmatch, direct antiglobulin test [DAT], free plasma hemoglobin, and coagulation profile) and the patient's first voided urine sample (to test for free hemoglobinuria). Despatch immediately to the blood bank with a completed adverse transfusion reaction form.
6. DOCUMENTATION: Record a comprehensive narrative note detailing the exact time the reaction commenced, the volume of blood infused, initial symptoms, chronological vital signs, all medical notifications, interventions instituted, and the patient's clinical outcome.