Survey of Red Cell Transfusion Patterns in Patients with Chronic Bone Marrow Failure Disorders in Northern Alberta, Canada

BACKGROUND

Patients with chronic bone marrow failure syndromes often become dependent on recurrent red blood cell (RBC) transfusions (txn). Given the lack of standard RBC txn guidelines in this population, txn practices can be quite variable. Our aim is to study the pattern of RBC txns in chronically transfused patients with bone marrow failure syndromes in our jurisdiction to better understand Hemoglobin (Hb) triggers and volumes transfused.

METHODS

A chronic txn database containing information regarding all patients receiving a RBC txn at least once every two months for a minimum of six consecutive months between January 1, 2011 and December 31, 2014 exists for all 13 sites within the Edmonton Zone in Alberta, Canada. This database was queried for all adult patients (age > 18) with chronic bone marrow failure syndromes. We defined bone marrow failure as the intrinsic inability of the bone marrow to produce adequate amounts of blood cells, but not due to acute leukemia or non-myeloid malignancies. Patients were excluded if bone marrow failure was not the primary indication for the RBC txns. The data elements extracted included median pre-txn Hb, median number of RBCs transfused per episode, and location of txn. Data was inserted into an EXCEL spreadsheet for analysis.

RESULTS

We found 126 patients in the chronic transfusion database with bone marrow failure syndromes, who received RBCs between January 1, 2011 and December 31, 2014. We removed 10 patients with concurrent acute leukemia or non-myeloid malignancies, 7 with additional non-bone marrow causes for cytopenias, 4 with non-hematologicalmalignancies, and 3 who were <18 years of age. We included 102 out of 126 patients, 65 with myelodysplastic syndrome, 22 with myeloproliferative neoplasm, 9 with aplastic anemia, 5 with chronic myelomonocytic leukemia and 4 with pure red cell aplasia. Three patients had combined diagnoses. Mean age at time of txn was 73.9 years(range 23 to 99) and 66.72% were male. Medical therapies used included erythropoietin stimulating agents (29), iron chelation therapy (28), Azacitidine (17), Hydroxyurea (17), and stem cell transplantation (5).

In total, there were 5889 units of RBC transfused, 3809 (65%) at the Hematology based tertiary care facility (HEM), 1025 (17%) in non-Hematology tertiary centers (Non-HEM), and 1055 (18%) in community based facilities (COM). The differences in pre-txn Hbs based on site are in Table 1. Over time, normalization across sites has occurred.

Over the 4 years, the mean total units of RBCs transfused per patient was 57.74 (range 13 to 297).

The median quantity of units of RBCs transfused per transfusion event was 2 in HEM and non-HEM, compared to 3 in COM. There were no changes in the medians through the years.

CONCLUSIONS

Pre-tx Hb remained stable in tertiary centers, but started higher in community centers and trended downward becoming similar to tertiary centers by 2014. However, the number of units of blood given at each transfusion event remains higher in community centers compared to tertiary centers.