Blood Transfusion Associated Adverse Reactions

This study will be a randomized, double-blinded, placebo-controlled study conducted at a university hospital. Forty children undergoing elective repair of a congenital heart defect will be included. The patients will be randomly allocated (20 patients per group) to receive a single intravenous dose of combined chlorpheniramine or normal saline immediately after separation from CPB, before protamine administration.

The prevalence of transfusion reactions is between 1 and 11% of transfusions. Most reactions are mild and do not pose a life-threatening risk to the patient. More serious problems may be the only manifestations that lead to suspicion of a transfusion reaction. Most noninfectious transfusion reactions are immune-mediated. Two main types of reactions can be distinguished: TACO (transfusion associated cardiac overload, which is a cardiogenic pulmonary edema) and TRALI (transfusion related acute lung injury, non-cardiogenic pulmonary edema). Although TRALI are diagnoses of exclusion, the presence of noncardiogenic pulmonary edema and respiratory problems in the vicinity of blood product transfusions should raise suspicion. Other signs of TRALI are hypotension and tachycardia, while in TACO arterial hypertension with positive water balance can be observed. According to previous reports, the prevalence of transfusion reactions in the neonatal population is approximately 8%. Factors associated with these reactions are low birth weight and low gestational age. However, diagnostic criteria of respiratory transfusion reactions are not uniform across studies, and often the generic terms "acute lung injury" have been used. Therefore, the primary objective of this study is to evaluate the respiratory trend during blood transfusions; secondary objectives are the study of risk factors for the development of respiratory worsening and the possible association with complications.