There are age-dependent trends for many of the tests, notably in RDW, MCMV, platelet count, and granulocyte and lymphocyte percentages. Sex-dependent changes involved hemoglobin values, and race-related trends centered around mononuclear and lymphocyte percentages, hematocrit, MCHC, MCH, and hemoglobin. This study reveals the potential for using data mining of large samples to yield potentially useful reference ranges.

Trp-999 is a key residue for the action of beta-galactosidases (Escherichia coli). Several site specific substitutions (Phe, Gly, Tyr, Leu) for Trp-999 were made. Each substitution caused greatly decreased affinities for substrates and inhibitors that bind in the "shallow" mode, while the affinities of inhibitors that bind in the "deep" mode were not decreased nearly as much. This shows that Trp-999 is important for binding in the shallow mode. The residue is also very important for binding glucose to galactosyl-beta-galactosidase (as a transgalactosidic acceptor). Substitution greatly diminished the affinity for glucose. Substitutions also changed the activation thermodynamics and, subsequently, the rates of the catalytic reactions. The enthalpies of activation of the glycolytic bond cleavage step (galactosylation, k(2)) became less favorable while the entropies of activation of that step became more favorable as a result of the substitutions. Differing magnitudes of these enthalpic and entropic effects with ONPG as compared to PNPG caused the k(2) values for ONPG to decrease but to increase for PNPG. The enthalpies of activation for the common hydrolytic step (degalactosylation, k(3)) increased while the entropies of activation for this step did not change much. As a result, k(3) became small and rate determining for each substituted enzyme. The substitutions caused the rate constant (k(4)) of the transgalactosidic acceptor reactions with glucose (for the formation of allolactose) to become much larger and of the same order of magnitude as the normally large rate constants for transgalactosidic acceptor reactions with small alcohols. This is probably because glucose can approach with less restriction in the absence of Trp-999. However, since glucose binds very poorly to the galactosyl-beta-galactosidases with substitutions for Trp-999, the proportion of lactose molecules converted to allolactose is small. Thus, Trp-999 is also important for ensuring that an appropriate proportion of lactose is converted to allolactose.

This study describes the implementation of a novel PLT dashboard suite. This suite significantly reduced PLT outdate rates at our institution over the 48-month study period.

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Background and Objectives: Current manual and automated phenotyping methods are based on visual detection of the antigen-antibody interaction. This approach has several limitations including the use of large volumes of patient and reagent red blood cells (RBCs) and antisera to produce a visually detectable reaction. We sought to determine whether the flow cytometry could be developed and validated to perform RBC phenotyping to enable a high-throughput method of phenotyping using comparatively miniscule reagent volumes via fluorescence-based detection of antibody binding.Materials and Methods: RBC phenotyping by flow cytometry was performed using monoclonal direct typing antisera (human IgM): anti-C, -E, -c, -e, -K, -Jk a , -Jk b and indirect typing antisera (human IgG): anti-k, -Fy a , -Fy b , -S, -s that are commercially available and currently utilized in our blood transfusion services (BTS) for agglutination-based phenotyping assays.Results: Seventy samples were tested using both flow-cytometry-based-phenotyping and a manual tube standard agglutination assay. For all the antigens tested, 100% concordance was achieved. The flow-cytometry-based method used minimal reagent volume (0.5-1 μl per antigen) compared with the volumes required for manual tube standard agglutination (50 μl per antigen)Conclusion: This study demonstrates the successful validation of flow-cytometrybased RBC phenotyping. Flow cytometry offers many benefits compared to common conventional RBC phenotyping methods including high degrees of automation, quantitative assessment with automated interpretation of results and extremely low volumes of reagents. This method could be used for high-throughput, low-cost phenotyping for both blood suppliers and hospital BTS.

Background:Effective blood inventory management reduces outdates of blood products. Multiple strategies have been employed to reduce the rate of red blood cell (RBC) unit outdate. We designed an automated real-time web-based dashboard interfaced with our laboratory information system to effectively recycle red cell units. The objective of our approach is to decrease RBC outdate rates within our transfusion service.Methods:The dashboard was deployed in August 2011 and is accessed by a shortcut that was placed on the desktops of all blood transfusion services computers in the Capital District Health Authority region. It was designed to refresh automatically every 10 min. The dashboard provides all vital information on RBC units, and implemented a color coding scheme to indicate an RBC unit's proximity to expiration.Results:The overall RBC unit outdate rate in the 7 months period following implementation of the dashboard (September 2011-March 2012) was 1.24% (123 units outdated/9763 units received), compared to similar periods in 2010-2011 and 2009-2010: 2.03% (188/9395) and 2.81% (261/9220), respectively. The odds ratio of a RBC unit outdate postdashboard (2011-2012) compared with 2010-2011 was 0.625 (95% confidence interval: 0.497-0.786; P < 0.0001).Conclusion:Our dashboard system is an inexpensive and novel blood inventory management system which was associated with a significant reduction in RBC unit outdate rates at our institution over a period of 7 months. This system, or components of it, could be a useful addition to existing RBC management systems at other institutions.

BACKGROUND: Phlebotomy for diagnostic testing is among the commonest hospital procedures, but hospitalwide surveys of all inpatients characterizing blood draw volumes have not been published. The objectives were to characterize the daily blood volumes drawn for diagnostic testing from patients discharged from a Canadian tertiary care center, describe the daily distributions of phlebotomy volumes across service locations, and describe changes in hemoglobin (Hb) and transfusion across service locations. STUDY DESIGN AND METHODS: Data wereobtained on all patients discharged between 2012 and 2014 using linked discharge abstract and laboratory data. Cumulative daily blood volume and draw frequency were reported by service and days since admission. Changes in Hb and red blood cell (RBC) transfusion rates were reported for nontransfused and transfused patients.RESULTS: Data were included on 59,715 subjects.Mean daily estimated blood loss varied from 8.5 AE 6.5 mL/day onward to 27.2 AE 20.0 mL/day in the intensive care unit (ICU; p < 0.001). Phlebotomy volumes were highest on the first day of admission and declined thereafter (p < 0.001). For nontransfused individuals in the first week of admission, Hb levels decreased by the highest percentage in the ICU. The rate of RBC unit transfusion was highest in the ICU (232.4 units/1000 patient-days; 95% confidence interval, 225.8-239.2; p < 0.0001 compared with all other locations). CONCLUSION:Considerable variation was observed in estimated blood loss due to diagnostic phlebotomy across different services within one teaching hospital. Thi information is foundational for planning interventions to minimize estimated blood loss from phlebotomy.ABBREVIATIONS: AMI = acute myocardial infarction; ICU = intensive care unit; IMCU(s) = medical intermediate care unit(s);

BACKGROUND Blood bank inventories must balance adequate supply with minimal outdate rates. The day‐to‐day practice of ordering red blood cell (RBC) inventory usually involves manually comparing current inventory levels with predetermined thresholds calculated from historical usage and ordering the difference. To date, there have been no published methods for ordering RBC inventory based on laboratory characteristics of admitted patients. STUDY DESIGN AND METHODS We designed and implemented a blood ordering algorithm to provide a more accurate measure of predicted RBC utilization in our institution. Cerner Command Language (Cerner Millennium) was used to extract and combine historical RBC unit usage, current inventory levels, and system‐wide hematology values and blood groups. This report contains a suggested order based on current inventory, historical inventory data, ABO group, and the current “anemia index” for the institution. RESULTS The mean daily total RBC inventory was significantly reduced after implementation (401.7 units vs. 309.0 units, p < 0.05). There was a significant reduction in monthly RBC outdates in this period (19.1 vs. 8.1, p < 0.05). The age of RBCs at time of transfusion was reduced as well. CONCLUSION We developed a novel algorithm that automatically generates a suggested RBC inventory order using real‐time hospital‐wide survey of patient ABO typing, hematology values, and historical data. After implementation of the algorithm we demonstrated a significant reduction in daily inventory levels and RBC outdate rates.