Abstract
An estimated 13,785,000 units of packed red blood cells (PRBC) were transfused in the United States in 2011 of which an estimated 57.9% were found to be from the general medical service, the ICU or hematology/oncology. Risks of blood transfusion include infections, transfusion reactions circulatory overload, and transfusion-related immunomodulation. Furthermore, there is an economic cost to the administration of blood and a personal cost to those volunteers who give their time.
There have been a number of guidelines published for the administration of PRBCs. In the past year, the American Association of Blood Banks released new guidelines for PRBC transfusion in hospitalized, hemodynamically stable patients. These guidelines set a threshold Hb of ≤7 g/dL in critically-ill patients, and a Hb ≤8 g/dL for surgical patients, for patients with pre-existing cardiovascular disease, or for patients with relevant symptoms. Symptoms were defined as tachycardia, chest pain or hypotension not corrected by crystalloids.
We studied the potential impact on our inpatient hospital utilization of PRBC over time in relation to the publication of recent guidelines.
With IRB approval, a retrospective study of PRBC transfusion at New Hanover Regional Medical Center in Wilmington, NC was conducted. The primary endpoint of the study was to evaluate the impact of the new AABB guidelines on the transfusion utilization in the first 12 months. Secondary endpoints included a cost analysis, an evaluation of the use of PRBC for two pre-specified Hb levels, and a quantification of the number of units transfused.
A total of 337 patients were reviewed. 116 were excluded due to one of the following reasons: anemia attributed to active blood loss, the presence of stage 5 chronic kidney disease, the presence of an acute coronary syndrome, the recent administration of outpatient transfusions, the use of blood products besides PRBCS, and the timing of a transfusion in the postoperative period. We randomly assigned two separate timeframes to review transfusions at ≤ 4 months and 8-12 months after the AABB guidelines were published. Data was analyzed using Chi-square and T tests.
The average pre-treatment hemoglobin for the group ≤4 months was 7.82 ± 0.85 and 7.42 ± 0.92 for the 8-12 month group (p=0.0009). The average number of units transfused were 1.66 ± 0.53 and 1.78 ± 0.58 (P=0.1133), respectively. For those patients whose Hb was ≤ 7.0, there was a 21.6% reduction in inappropriate transfusions 8-12 months after the guidelines were released compared with the first 4 months (Chi-Square p = 0.0070). For those patients whose Hb was ≤ 8.0, the number of inappropriate transfusions went from 40.7% in the first group to 17.3% in the second group (Chi-Square p=0.0001).
The total cost of transfusions to the patients was estimated to be $102,400 and $55,600 to the hospital. The potential savings if all transfusions were given according to the new guidelines is estimated to be $66,389 to the patients and $36,037 to the hospital.
A total of 11,577 transfusions were given between 6/12/12-3/13/13. If the guidelines had been strictly followed, the number of transfusions would have been reduced to 3,855 transfusions.
An improvement in adherence to AABB guidelines with a more restrictive PRBC transfusion strategy was found over time. This can be attributed to physicians practicing evidenced-based medicine. Data of transfusions at pre-treatment Hb ≤7, suggest that physicians are becoming more restrictive in their threshold for transfusions with a statistically significance in the drop of the average pre-treatment hemoglobin. Despite this restrictive pattern, physicians are still uncomfortable at transfusing 1 unit at a time. Although it was not statistically significant between the two groups, the average number of units transfused were ≥1.5, and 67% of the time 2 units were given. Overtransfusion with PRBCs is a problem that needs to be addressed. Physicians should give one unit and reassess for an appropriate response. This strategy will reduce cost to the patient and hospital.
We feel that additional improvement is still possible and we are forming a blood management committee to promote better PRBC transfusion practice guidelines. We plan a series of educational presentations to each department along with a new Computerized Physician Order Set to improve patient care and reduce overall cost to the health care system.
No relevant conflicts of interest to declare.
Author notes
Asterisk with author names denotes non-ASH members.
