Many adverse events can result from the rapid transfusion of blood products to children. At times, they can only be managed and not prevented. Transfusion-associated hyperkalemia (TAH) has been associated with cardiac arrest in patients receiving large volume or rapidly administered RBC transfusions. Currently, there are not pediatric-specific diagnostic criteria for transfusion-associated circulatory overload (TACO). Both large fluid volumes and a rapid rate of transfusion have been implicated, although the etiology is usually multifactorial. Hypocalcemia is attributed to citrate binding of calcium during rapid transfusion. The downstream metabolic effects of transfusion-induced hypothermia are extensive, including reduced metabolism of citrate preservative, a leftward shift of the oxyhemoglobin-dissociation curve, platelet dysfunction, and reduced procoagulant activity. Venous air embolism (VAE) can occur with any infusion device because fluid infusion systems contain many potential air entrainment sites. The key to safe management of any rapidly administered blood transfusion is knowledge of the potential side effects and an understanding of which patients are at greatest risk.