Background Hyperkalemia is a rare life‐threatening complication of red blood cell (RBC) transfusion. Stored RBCs leak intracellular potassium (K+) into the supernatant; irradiation potentiates the K+ leak. As the characteristics of patients and implicated RBCs have not been studied systematically, a multicenter study of transfusion‐associated hyperkalemia (TAH) in the pediatric population was conducted through the AABB Pediatric Transfusion Medicine Subsection. Study Design The medical records of patients <18 years old were retrospectively queried for hyperkalemia occurrence during or ≤12 h after the completion of RBC transfusion in a 1‐year period. Collected data included patient demographics, diagnosis, medical history, timing of hyperkalemia and transfusion, mortality, and RBC unit characteristics. Results/Findings A total of 3777 patients received 19,649 RBC units during the study period in four facilities. TAH was found in 35 patients (0.93%) in 37 occurrences. The patient median age and weight were 1.28 years and 9.80 kg, respectively. All patients had multiple serious comorbidities. There were 79 RBC units transfused in the TAH events; 62% were irradiated, and the median age of the units was 10 days. The median total RBC volume transfused ≤12 h before TAH was 24% of patient estimated total blood volume, and the median infusion rate (IR) was19.6 ml/kg/h. Mortality rate within 1 day after the TAH event was 20%. Conclusions The prevalence of TAH in children was low; however, the 1‐day mortality rate was 20%. Patients with multiple comorbidities may be at higher risk for TAH. The IR was higher for patients who had TAH than the IR threshold for safe transfusion.

The population at our institution is reflective of the previously reported standards for the genetic predispositions toward thrombosis. Although older age is associated with a lower incidence of thrombosis, the presence of a central venous access device is detrimental. Accumulation of factors results in an increased risk of thrombosis. This article suggests that when inserting a central venous access device, consideration of a hypercoagulation workup should occur. Those with any two or more risk factors, genetic or acquired, and the comorbidity of a CVL may warrant consideration for the institution of anticoagulation with an agent like low molecular weight heparin.