Introduction and General Principles

Blood component transfusions should be based on strict guidelines that include clinical parameters besides threshold laboratory values.
Component therapy optimizes the utilization of donated blood and prevents unnecessary exposure to blood components that are not required.
Whole blood is not recommended for transfusing neonates for routine anemia.
Care taken to reduce blood loss through micro-sampling and delayed cord clamping can significantly decrease the need for transfusions.

Packed Red Blood Cells Transfusion

Packed red blood cells (PRBC) must be transfused only to patients lacking sufficient oxygen-carrying capacity due to anemia, hemorrhage, or hemoglobinopathy.
Restrictive transfusion thresholds are generally recommended, as liberal transfusions do not improve health outcomes and increase exposure to blood products.
Transfusion thresholds depend on postnatal age, gestational age, and the need for respiratory support.

Postnatal Age	Ventilated Neonates	On Oxygen or CPAP/NIPPV	No Respiratory Support
First 24 hours	< 12.0 g/dL (35%)	< 12.0 g/dL (35%)	< 10.0 g/dL (30%)
Days 2 to 7	< 12.0 g/dL (35%)	< 10.0 g/dL (30%)	< 10.0 g/dL (30%)
Days 8 to 14	< 10.0 g/dL (30%)	< 9.5 g/dL (28%)	< 7.5 to 8.5 g/dL (23-25%)
Day 15 onwards	< 10.0 g/dL (30%)	< 8.5 g/dL (25%)	< 7.5 g/dL (23%)

Table: PRBC transfusion thresholds for preterm neonates < 32 weeks birth gestation.

Clinical Condition	Suggested Transfusion Threshold (Hemoglobin)
Severe pulmonary disease or severe cardiac disease	< 10.0 g/dL (30%)
Moderate pulmonary disease	< 8.0 g/dL (24%)
Prior to major surgery	< 10.0 g/dL (30%)
Symptomatic anemia	< 7.0 g/dL (21%)

Table: PRBC transfusion thresholds for term neonates.

Small volume top-up transfusions of 10 to 15 mL/kg are preferred in babies < 32 weeks due to the reported risk of necrotizing enterocolitis at higher volumes.
The recommended rate for PRBC transfusion is 5 mL/kg/hour.
Transfusions should be initiated at a slow rate to watch for reactions and completed over 3 to 4 hours.
Diuretics are not routinely recommended before or after PRBC transfusion unless specifically indicated for pre-existing cardiac failure.

Liberal platelet transfusions are associated with no benefits and a higher potential for harm, including major bleeding and bronchopulmonary dysplasia.
Transfusion thresholds are determined by the presence of bleeding, planned surgeries, and the underlying clinical condition.

Platelet Count	Clinical Condition for Transfusion
< 25,000 / mm³	Stable preterm neonates with no active bleeding.
< 50,000 / mm³	Neonates with clinical bleeding, current coagulopathy, or before invasive procedures.
< 100,000 / mm³	Major bleeding (e.g., significant intraventricular hemorrhage) or major surgery.
< 30,000 / mm³	Neonates with fetal and neonatal alloimmune thrombocytopenia (FNAIT).

The typical dose for platelet transfusion is 10 to 20 mL/kg, which can increase the platelet count by approximately 100,000 / mm³.
The recommended rate of transfusion is 10 to 20 mL/kg/hour.
Platelets should be transfused immediately after receiving them from the blood center and completed within 30 to 60 minutes if no adverse reaction is noted.

Fresh frozen plasma (FFP) should be transfused only to correct clinical coagulopathy.
FFP should not be transfused merely based on deranged laboratory coagulation reports without clinical bleeding.
Clinical indications include disseminated intravascular coagulation (DIC), large gastrointestinal bleeds with shock, and significant pulmonary hemorrhage.
FFP should not be used for volume replacement during hypotension or for the prevention of intraventricular hemorrhage in preterm infants.

The recommended dose is 10 to 15 mL/kg, which increases the levels of coagulation factors by 15% to 20%.
FFP must be transfused over 30 to 60 minutes.

Cytomegalovirus (CMV) safe blood: Preterm neonates < 30 weeks or < 1,500 g birth weight are at high risk of postnatal CMV infection. Leukoreduced or CMV-negative blood products should be used.
Leukoreduction: Removing white blood cells decreases the risk of CMV transmission, febrile non-hemolytic reactions, and human leukocyte antigen (HLA) alloimmunization.
Irradiation: Cellular components should be irradiated with 25-50 Gray to render T lymphocytes incapable of replication. This prevents transfusion-associated graft-versus-host disease (TA-GVHD) in immunocompromised preterm neonates.
Washing: Removing acellular plasma fluids reduces exposure to donor antibodies, lowering the risk of severe allergy and hyperkalemia.

Both the mother's and neonate's blood samples should be obtained for initial ABO and Rhesus (Rh) group determination.
Donor PRBC must be cross-matched with maternal blood to test for atypical antibodies that may persist in the neonate.
In emergencies where cross-matching is not possible, emergency-release blood (type O Rh-negative PRBC, AB plasma) may be issued.

All blood components must be transfused through a standard filter (170-260 microns) to remove clots and clumps.
Blood products should be examined for any hemolysis, clot, or discoloration prior to starting the transfusion.
It is not recommended to administer any medication or solution through the same intravenous line used for blood components, except 0.9% normal saline.
Satellite bags (small 30 mL bags split from a standard adult PRBC bag) should be used for serial top-up transfusions. This limits multiple donor exposures.

Transfusion-transmitted infections: Although risks are reduced by modern screening, transmission of HIV, Hepatitis B and C, and CMV remains a serious concern.
Transfusion-associated necrotizing enterocolitis (TRANEC): NEC occurring within 24 to 48 hours of PRBC transfusions in very low birth weight babies may be related to the transfusion or the underlying severe anemia.
Metabolic complications: Massive transfusions can cause hypoglycemia, hyperkalemia, and hypocalcemia.
Transfusion-associated acute lung injury (TRALI): Presents as worsening respiratory distress within 6 hours of transfusion due to non-cardiogenic pulmonary edema.
Transfusion-associated circulatory overload (TACO): Occurs with rapid and large volume transfusions, leading to cardiogenic edema and hypertension.