Platelet transfusion in critical care: A new method to analyze transfusion practice based on decision time intervals.

BACKGROUND: While prior studies of platelet transfusion in critical care have focused on transfusions given, proper analysis of clinical transfusion practice also requires consideration of the decision not to transfuse. STUDY DESIGN AND METHODS: We introduce a new method to assess transfusion practice based on decision time intervals (DTIs). Each patient's intensive care (ICU) stay was segmented into a series of DTIs defined by a time interval following results of a complete blood count (CBC). We studied the presence of 17 clinical factors during each DTI whether transfusion was given or not. We used a generalized linear mixed model to assess the most influential clinical triggers for platelet transfusion. RESULTS: Among 6125 ICU patients treated between October 2016 and October 2021, we analyzed 39,745 DTIs among patients (n = 2921) who had at least one DTI with thrombocytopenia (≤150,000/µL). We found no association between platelet count and two markers of bleeding: drop in hemoglobin and chest tube drainage. We found that the majority of DTIs were associated with no platelet transfusion regardless of the platelet count; that no specific platelet value triggered transfusion; but rather that multiple clinical factors in conjunction with the platelet count influenced the decision to transfuse. DISCUSSION: DTI analysis represents a new method to assess transfusion practice that considers both transfusions given and not given, and that analyzes clinical circumstances present when decisions regarding transfusion are made. The method is easily adapted to blood components other than platelet transfusions and is easily extended to other ICU and other hospital settings.

Time interval between antibody investigations among patients who demonstrate serial red cell antibody formation.

BACKGROUND: Current national standards for pretransfusion testing do not address the frequency or optimal time interval to repeat antibody identification testing for patients in whom antibodies have been previously detected. STUDY DESIGN AND METHODS: A retrospective review was performed of patients with existing red blood cell (RBC) antibodies who subsequently developed new antibody specificities. Data were drawn from a single institution where the antibody investigation was repeated if the screen suggested a new antibody or if 14 days had elapsed since the previous investigation. Clinically insignificant or drug-dependent antibodies were excluded. Among cases in which new antibodies were detected within 30 days of a previous sample that already demonstrated existing antibodies, the median and lower 95% confidence intervals for the number of days between the detection of the existing and new antibodies were determined. RESULTS: Over a 9-year period, among 2114 patients with more than 1 antibody, 699 (33%) had serially detected antibodies from separate samples. Among 152 patients whose subsequent antibody was detected within 30 days of the existing antibodies, the median time interval to detection of the new antibody was 13 days. The lower 95% confidence interval was 1 day. By Day 3, 18% of the new antibodies had already appeared. CONCLUSION: In patients who form multiple antibodies, the serial emergence of clinically significant antibodies is common. In some patients, detection of a new specificity occurs in a sample drawn shortly after the sample that demonstrated the first antibody. These results have implications for the frequency of pretransfusion testing.

Survival after ultramassive transfusion: a review of 1360 cases.

BACKGROUND: Information about patient survival after transfusion of multiple blood volumes is limited, and most reports have focused on trauma patients. STUDY DESIGN AND METHODS: Retrospective study of blood use and survival at 11 hospitals in six nations between 2009 and 2013. Ultramassive transfusion (UMT) was defined as transfusion of 20 or more red blood cell (RBC) units over the course of any 2 consecutive calendar days. RESULTS: A total of 1975 patients received UMT and a representative sample of 1360 patients was studied in detail. Patients were grouped into seven diagnostic categories: solid organ transplantation (n = 411), cardiac or major vascular surgery (n = 317), general surgery (n = 228), trauma (n = 221), general medicine (n = 124), obstetrics (n = 23), and other (n = 36). During the 7 days after initiation of UMT, these patients used more than 120,000 blood components. The median (interquartile range) blood use was 35 (26-50) RBC units, 30 (20-47) plasma units, and 7 (4-13) platelet doses. Five- and 30-day survival significantly declined with increasing RBC use. Overall survivals of patients receiving UMT were 71% (5 day) and 60% (30 day), and in the subset of 165 patients receiving 60 or more RBC units over 2 consecutive days, 5-day survival was 54% ranging from 17% (trauma) to 75% (solid organ transplant). The decline in survival with increasing RBC transfusions was minimal for patients undergoing solid organ transplantation and was most pronounced for trauma and nonsurgical bleeding patients. CONCLUSION: Trauma was not the leading cause of UMT. Increasing RBC requirements were significantly associated with decreasing survival. However, survival was more strongly associated with diagnostic category than total RBCs transfused, with highest survival rates in solid organ transplant surgery.

Transfusion Medicine in Sub-Saharan Africa: Conference Summary.

In November 2014, a 3-day conference devoted to transfusion medicine in sub-Saharan Africa was held in Kampala, Uganda. Faculty from academic institutions in Uganda provided a broad overview of issues pertinent to transfusion medicine in Africa. The conference consisted of lectures, demonstrations, and discussions followed by 5 small group workshops held at the Uganda Blood Transfusion Service Laboratories, the Ugandan Cancer Institute, and the Mulago National Referral Hospital. Highlighted topics included the challenges posed by increasing clinical demands for blood, the need for better patient identification at the time of transfusion, inadequate application of the antiglobulin reagent during pretransfusion testing, concern regarding proper recognition and evaluation of transfusion reactions, the expanded role for nurse leadership as a means to improve patient outcomes, and the need for an epidemiologic map of blood usage in Africa. Specialty areas of focus included the potential for broader application of transcranial Doppler and hydroxyurea therapy in sickle cell disease, African-specific guidelines for transfusion support of cancer patients, the challenges of transfusion support in trauma, and the importance of African-centered clinical research in pediatric and obstetric transfusion medicine. The course concluded by summarizing the benefits derived from an organized quality program that extended from the donor to the recipient. As an educational tool, the slide-audio presentation of the lectures will be made freely available at the International Society of Blood Transfusion Academy Web site: http://www.isbtweb.org/academy/.

Hyperhemolysis syndrome in a patient without a hemoglobinopathy, unresponsive to treatment with eculizumab.

BACKGROUND: Hyperhemolysis is a serious transfusion reaction, most often described in patients with hemoglobinopathies. Hyperhemolysis is characterized by the destruction of host red blood cells (RBCs), in addition to donor RBCs, via an unknown mechanism. STUDY DESIGN AND METHODS: We present the case of a 58-year-old woman with treated human immunodeficiency virus and a normal hemoglobin (Hb) electrophoresis who developed hyperhemolysis in the setting of a delayed hemolytic transfusion reaction (DHTR). RESULTS: The patient was ABO group B and had a previously identified anti-Fy(b) alloantibody. After transfusion of Fy(b)--RBCs, she developed a DHTR and was found to have anti-E, anti-C(w), anti-s, and an additional antibody to an unrecognized high-frequency RBC alloantigen. Subsequent transfusion of ABO-compatible RBCs that were negative for Fy(b), E, C(w), and s antigens resulted in immediate intravascular hemolysis. In the absence of bleeding, her hematocrit (Hct) decreased to 10.2%. An extensive serologic evaluation failed to identify the specificity of the high-frequency antibody. Severe hemolytic reactions also occurred despite pretransfusion conditioning with eculizumab. The Hct and clinical symptoms slowly improved after the cessation of transfusions and treatment with erythropoietin and steroids. This case demonstrates several noteworthy features including hyperhemolysis in a patient without a Hb disorder, the development of an antibody to an unknown RBC antigen, and the failure of eculizumab to prevent intravascular hemolysis after transfusion. CONCLUSION: Hyperhemolysis is not restricted to patients with hemoglobinopathies. Whether eculizumab offers any benefit in the hyperhemolysis syndrome or in the prevention of intravascular hemolysis due to RBC alloantibodies remains uncertain.

Utilization management in the blood transfusion service.

The scope of activity of the Blood Transfusion Service (BTS) makes it unique among the clinical laboratories. The combination of therapeutic and diagnostic roles necessitates a multi-faceted approach to utilization management in the BTS. We present our experience in utilization management in large academic medical center.

Reversal of drug-induced anticoagulation: old solutions and new problems.

Anticoagulant drugs are taken by millions of patients throughout the world. Warfarin has been the most widely prescribed anticoagulant for decades. In recent years, new oral anticoagulants have been approved for use, are being positioned as alternatives to warfarin, and represent an enormous market opportunity for pharmaceutical companies. Requests for urgent reversal of anticoagulants are not uncommon especially in the setting of critical bleeding. This review summarizes information on reversal of warfarin by vitamin K, plasma, prothrombin complex concentrates, and recombinant VIIa. In addition, we emphasize the lack of current evidence supporting reversibility of the new oral direct thrombin inhibitors and Factor Xa inhibitors. This review is presented to assist transfusion medicine specialists, hematologists, and other clinicians who prescribe blood components for reversal of drug-induced anticoagulation.

Errors in patient specimen collection: application of statistical process control.

BACKGROUND: Errors in the collection and labeling of blood samples for pretransfusion testing increase the risk of transfusion-associated patient morbidity and mortality. Statistical process control (SPC) is a recognized method to monitor the performance of a critical process. An easy-to-use SPC method was tested to determine its feasibility as a tool for monitoring quality in transfusion medicine. STUDY DESIGN AND METHODS: SPC control charts were adapted to a spreadsheet presentation. Data tabulating the frequency of mislabeled and miscollected blood samples from 10 hospitals in five countries from 2004 to 2006 were used to demonstrate the method. Control charts were produced to monitor process stability. RESULTS: The participating hospitals found the SPC spreadsheet very suitable to monitor the performance of the sample labeling and collection and applied SPC charts to suit their specific needs. One hospital monitored subcategories of sample error in detail. A large hospital monitored the number of wrong-blood-in-tube (WBIT) events. Four smaller-sized facilities, each following the same policy for sample collection, combined their data on WBIT samples into a single control chart. One hospital used the control chart to monitor the effect of an educational intervention. CONCLUSION: A simple SPC method is described that can monitor the process of sample collection and labeling in any hospital. SPC could be applied to other critical steps in the transfusion processes as a tool for biovigilance and could be used to develop regional or national performance standards for pretransfusion sample collection. A link is provided to download the spreadsheet for free.