Massive transfusions and severe hypocalcemia: An opportunity for monitoring and supplementation guidelines.

BACKGROUND: Massive transfusion protocols (MTPs) are associated with severe hypocalcemia, contributing to coagulopathy and mortality in severely injured patients. Severity of hypocalcemia following massive transfusion activation and appropriate treatment strategies remain undefined. STUDY DESIGN AND METHODS: This was a retrospective study of all MTP activations in adult trauma patients at a Level 1 trauma center between August 2016 and September 2017. Units of blood products transfused, ionized calcium levels, and amount of calcium supplementation administered were recorded. Primary outcomes were ionized calcium levels and the incidence of severe ionized hypocalcemia (iCa ≤1.0 mmol/L) in relation to the volume of blood products transfused. RESULTS: Seventy-one patients had an MTP activated during the study period. The median amount of packed red blood cells (PRBCs) transfused was 10 units (range 1-52). A total of 42 (59.1%) patients had periods of severe hypocalcemia. Patients receiving 13 or more units of PRBC had a greater prevalence of hypocalcemia with 83.3% having at least one measured ionized calcium ≤1.0 mmoL/L (p = .001). The number of ionized calcium levels checked and the amount of supplemental calcium given in patients who experienced hypocalcemia varied considerably. DISCUSSION: Severe hypocalcemia commonly occurs during MTP activations and correlates with the number of packed red blood cells transfused. Monitoring of ionized calcium and amount of calcium supplementation administered is widely variable. Standardized protocols for recognition and management of severe hypocalcemia during massive transfusions may improve outcomes.

[Treatment of transfusional iron overload].

Frequent packed red blood cell (pRBC) transfusion can cause transfusional iron overload. Excess iron generates reactive oxygen species and provokes organ dysfunction. In lower-risk myelodysplastic syndrome (MDS), hyperferritinemia is known as one of the negative prognostic factors. Thus far, iron chelation therapy (ICT) is the only effective treatment for chronic iron overload induced by transfusion. Transfusional iron overload is diagnosed when serum ferritin (SF) levels are ≥500 ng/ml and cumulative volume of pRBC transfusion is ≥20 JPN units. ICT should be initiated when SF levels are ≥1,000 ng/ml and will be further continued until SF levels decline to <500 ng/ml. ICT serves to ameliorate organ dysfunction. A prospective study demonstrated that in patients with lower-risk MDS, ICT can reduce the risk of combined events, including cardiac events, hepatic events, AML transformation, and death of any cause. In some patients, hematological improvement will be observed. However, clinical features underling this hematological phenomenon are not fully understood. Therefore, ICT should not be performed solely for the purpose of hematological recovery.

Iron overload in patients with myelodysplastic syndromes: An updated overview.

Myelodysplastic syndromes (MDS) encompass a heterogeneous group of clonal hematopoietic stem cell disorders characterized by a broad clinical spectrum related to ineffective hematopoiesis leading to unilineage or multilineage cytopenias, with a high propensity for transformation to acute myeloid leukemia. Iron overload has been recently identified as one of the important conditions complicating the management of these diverse disorders. The accumulation of iron is mainly related to chronic transfusions; however, evidence suggests a possible role for ineffective erythropoiesis and increased intestinal absorption of iron, related to altered hepcidin and growth differentiation factor-15 levels in the development of hemosiderosis in patients with MDS. In addition to its suggested role in the exacerbation of ineffective erythropoiesis, multiple reports have identified a prognostic implication for the development of iron overload in patients with MDS, with an improvement in overall survival after the initiation of iron chelation therapy. This review includes a detailed discussion of iron overload in patients with MDS whether they are undergoing supportive therapy or curative hematopoietic stem cell transplantation, with a focus on the mechanism, diagnosis, and effect on survival as well as the optimal management of this highly variable complication.