Evaluating patients with autoimmune hemolytic anemia in the transfusion service and immunohematology reference laboratory: pretransfusion testing challenges and best transfusion-management strategies.

The serologic evaluation of autoimmune hemolytic anemia (AIHA) confirms the clinical diagnosis, helps distinguish the type of AIHA, and identifies whether any underlying alloantibodies are present that might complicate the selection of the safest blood for any needed transfusion. The spectrum of testing is generally dependent on the amount and class (immunoglobulin G or M) of autoantibody as well as the resources and methodologies where testing is performed. The approach may range from routine pretransfusion testing, including the direct antiglobulin test, to advanced techniques such as adsorptions, elution, and red cell genotyping. When transfusion is needed, the selection of the optimal unit of red blood cells is based on urgency and whether time allows for the completion of sophisticated serologic and molecular testing methods. From the start of when AIHA is suspected until the completion of testing, communication among the clinical team and medical laboratory scientists in the transfusion service and immunohematology reference laboratory is critical as testing can take several hours and the need for transfusion may be urgent. The frequent exchange of information including the patient's transfusion history and clinical status, the progress of testing, and any available results is invaluable for timely diagnosis, ongoing management of the patient, and the safety of transfusion if required before testing is complete.

A report of cerebral malaria treated with automated red blood cell exchange.

BACKGROUND: Adjunctive automated whole blood or red blood cell exchange (RBCEx) can rapidly decrease malarial hyperparasitemia. Several case reports and series suggest improvement in clinical symptomatology; however, recent Centers of Disease Control and Prevention (CDC) recommendations concluded that RBCEx has no efficacy as an adjunctive therapy. We present a case of mental status changes secondary to cerebral malaria treated with automated RBCEx resulting in rapid and dramatic neurologic improvement. CASE REPORT: An 84-year-old Somali woman presented with a 3-day history of altered mental status, spiking fevers, chills, bilateral leg pain and weakness, and intermittent diarrhea. Her travel history included a recent trip to Kenya for 1 month without antimalarial chemoprophylaxis. During the hospital stay, her health declined, and she became obtunded. Physical examination revealed fever, tachypnea, hypertension, hypoxia, and no response to verbal or physical stimuli. Her hemoglobin decreased from 12.6 to 6.5 g/dL with 12% intraerythrocytic parasitemia by thin smear. Intraerythrocytic trophozoites and banana-shaped gametocytes were present consistent with Plasmodium falciparum. An emergent 1.5-volume RBC mass automated RBCEx and quinidine infusion decreased her parasitemia to 2%. The patient's mental status improved throughout the procedure, and after the 2½-hour procedure, the patient was alert, oriented, and speaking coherently. The patient continued to receive quinidine and artesunate 1 day later from CDC. CONCLUSION: Automated RBCEx transfusion reduced the parasite burden and restored neurologic functioning in a patient with cerebral malaria while awaiting definitive treatment with artesunate.

Comparing ε-Aminocaproic Acid and Tranexamic Acid in Reducing Postoperative Transfusions in Total Knee Arthroplasty.

Multiple studies have shown tranexamic acid (TXA) to reduce blood loss and transfusion rates in patients undergoing total knee arthroplasty (TKA). Accordingly, TXA has become a routine blood conservation agent for TKA. In contrast, ε-aminocaproic acid (EACA), a similar acting antifibrinolytic to TXA, has been less frequently used. This study evaluated whether EACA is as efficacious as TXA in reducing postoperative blood transfusion rates and compared the cost per surgery between agents. A multicenter retrospective chart review of elective unilateral TKA from April 2012 through December 2014 was performed. Five hospitals within a health care system participated. Data collected included age, gender, severity of illness score, use of antifibrinolytic and dose, red blood cell (RBC) transfusions and the number of units, and preadmission and discharge hemoglobin (Hb). Dosing of the antifibrinolytic differed based on the agent used, 5 or 10 g (based on weight) for EACA versus 1 g for TXA. The institutional acquisition cost of each antifibrinolytic was obtained and averaged over the study period. Of 2,922 primary unilateral TKA cases, 820 patients received EACA, 610 patients received TXA, and 1,492 patients received no antifibrinolytic (control group). Compared with the control group both EACA and TXA groups had significantly fewer patients transfused (EACA 2.8% [p < 0.0001], TXA 3.2% [p < 0.0001] vs. control 10.8%) and lower mean RBC units transfused per patient (EACA 0.05 units/patient [pt] [p < 0.0001], TXA 0.05 units/pt [p < 0.0001] vs. control 0.19 units/pt]. There was no difference in mean RBC units transfused per patient, percentage of patients transfused, and discharge Hb levels between the EACA and TXA groups (p = 0.822, 0.236, and 0.322, respectively). Medication acquisition cost for EACA averaged $2.23 per surgery compared with TXA at $39.58 per surgery. Administration of EACA or TXA significantly decreased postoperative transfusion rates compared with no antifibrinolytic therapy. Utilization of EACA for unilateral TKA proved to be comparable to TXA in all studied aspects at a lower cost. The level of evidence for the study is Level 3.

Comparison of ε-Aminocaproic Acid and Tranexamic Acid in Reducing Postoperative Transfusions in Total Hip Arthroplasty.

BACKGROUND: Use of antifibrinolytic agents in total hip arthroplasty (THA) is well supported; however, most studies used tranexamic acid (TXA), whereas few used ε-aminocaproic acid (EACA), a similar antifibrinolytic. This study compares the efficacy and cost per surgery of intraoperative infusion of EACA and TXA in reducing postoperative blood transfusion rates in THA. METHODS: Retrospective chart review of 1799 primary unilateral THA cases from April 2012 through December 2014 at 5 hospitals within our health care network. RESULTS: In our cohort, 711 received EACA, 445 received TXA, and 643 (control group) received no antifibrinolytic. Both antifibrinolytic groups had significantly fewer patients receiving red blood cell (RBC) transfusions when compared with control group (EACA 6.8% [P < .0001], TXA 9.7% [P < .0001] vs control group 24.7%). Average number of RBC units per patient were similar for EACA and TXA (0.11 units/patient and 0.15 units/patient, respectively), and both were significantly lower than the control group (0.48 units/patient, P < .0001). No significant difference was noted in mean RBC units per patient and percentage of patients transfused between EACA and TXA groups (P = .144, P = .074). Logistic regression showed no difference between EACA and TXA when adjusting for age, gender, higher severity of illness levels, admission hemoglobin, performing surgeon, and hospital. Medication acquisition cost for EACA averaged $2.70 per surgery compared with TXA at $39.58 per surgery. CONCLUSION: Intraoperative antifibrinolytic use significantly decreases need for postoperative blood transfusions. At our institution, EACA is comparable to TXA in THA for reducing transfusion rates while at a lower cost per surgery.

Red cell storage age policy for patients with sickle cell disease: A survey of transfusion service directors in the United States.

In patients with sickle cell disease (SCD), the effects of the red cell storage lesion are not well defined. The objective of this study was to determine the prevalence of transfusion services that limit red cell units by storage age for patients with SCD. We developed a 22 question survey of transfusion service director opinions and their corresponding blood bank policies. Target subjects were systematically identified on the AABB website. Responses were recorded in SurveyMonkey and summarized using standard statistical techniques. Ninety transfusion service directors responded to the survey. Response rate was 22%. Only 23% of respondents had storage age policies in place for patients with SCD, even though 36% of respondents consider older units to be potentially harmful in this patient population. Of those with a policy, a less-than 15 day storage age requirement was most often used (75%), but practices varied, and most respondents (65%) agreed that evidence-based guidelines regarding storage age are needed for patients with SCD. Policies, practices and opinions about the risks of older units for patients with SCD vary. As patients with SCD may have unique susceptibilities to features of the red cell storage lesion, prospective studies in this population are needed to determine best practice.

Effects of red-cell storage duration on patients undergoing cardiac surgery.

BACKGROUND: Some observational studies have reported that transfusion of red-cell units that have been stored for more than 2 to 3 weeks is associated with serious, even fatal, adverse events. Patients undergoing cardiac surgery may be especially vulnerable to the adverse effects of transfusion. METHODS: We conducted a randomized trial at multiple sites from 2010 to 2014. Participants 12 years of age or older who were undergoing complex cardiac surgery and were likely to undergo transfusion of red cells were randomly assigned to receive leukocyte-reduced red cells stored for 10 days or less (shorter-term storage group) or for 21 days or more (longer-term storage group) for all intraoperative and postoperative transfusions. The primary outcome was the change in Multiple Organ Dysfunction Score (MODS; range, 0 to 24, with higher scores indicating more severe organ dysfunction) from the preoperative score to the highest composite score through day 7 or the time of death or discharge. RESULTS: The median storage time of red-cell units provided to the 1098 participants who received red-cell transfusion was 7 days in the shorter-term storage group and 28 days in the longer-term storage group. The mean change in MODS was an increase of 8.5 and 8.7 points, respectively (95% confidence interval for the difference, -0.6 to 0.3; P=0.44). The 7-day mortality was 2.8% in the shorter-term storage group and 2.0% in the longer-term storage group (P=0.43); 28-day mortality was 4.4% and 5.3%, respectively (P=0.57). Adverse events did not differ significantly between groups except that hyperbilirubinemia was more common in the longer-term storage group. CONCLUSIONS: The duration of red-cell storage was not associated with significant differences in the change in MODS. We did not find that the transfusion of red cells stored for 10 days or less was superior to the transfusion of red cells stored for 21 days or more among patients 12 years of age or older who were undergoing complex cardiac surgery. (Funded by the National Heart, Lung, and Blood Institute; RECESS ClinicalTrials.gov number, NCT00991341.).

Comparison and stability of ADAMTS13 activity in therapeutic plasma products.

BACKGROUND: The von Willebrand factor (VWF)-cleaving protease, ADAMTS13, is often deficient in cases of thrombotic thrombocytopenic purpura (TTP). The primary treatment of TTP is therapeutic plasma exchange (TPE) utilizing a variety of plasma products that help restore ADAMTS13 activity. However, multiple replacement products are available to choose from. Thawed plasma products have a variable refrigerated shelf life depending on the product type; stability of ADAMTS13 in thawed products stored at 1 to 6 degrees C has not been determined. STUDY DESIGN AND METHODS: ADAMTS13 activity was measured in three types of plasma products and cryoprecipitate. Fresh-frozen plasma (FFP) aliquots and cryoprecipitate-poor plasma (CPP) products were produced from 10 whole-blood (WB) donations. Twenty-four-hour plasma products were manufactured from 10 additional WB donations. ADAMTS13 activity in these products at time of thaw and after 5 days of storage at 1 to 6 degrees C was measured with a modified version of the FRETS-VWF73 fluorogenic assay. ADAMTS13 activity at time of thaw was measured in 10 units of cryoprecipitate and five related CPP products. RESULTS: ADAMTS13 is present in similar amounts in FFP, CPP, and 24-hour plasma products. Storage at 1 to 6 degrees C for up to 5 days did not significantly diminish ADAMTS13 activity. The concentration of ADAMTS13 in cryoprecipitate was significantly higher than that observed in plasma products. CONCLUSION: FFP, CPP, and 24-hour plasma products should be equally effective for ADAMTS13 restoration through TPE and should remain so for the duration of the shelf life of the thawed products.