bluuebunny/crossref_metadata_2025 huggingface dataset:
P10 Transfusion‐Related Cost of Aprotinin in Scoliosis Surgery for Children and Adolescents.
Authors: McCahon R. , Lamb J.
Published: September 2006

Introduction  Scoliosis surgery causes major blood loss. Previous research has demonstrated that aprotinin reduces perioperative blood loss and thus transfusion. To date there has not been a cost analysis of the effect of aprotinin on transfusion requirement in scoliosis surgery.

Methods  Retrospective case series of all patients <18 years old at the time of their scoliosis surgery. All patients were operated on and anaesthetised by the same consultant surgeon and anaesthetist between May 2002 and February 2006. Estimated blood volume (EBV) was 70 mL kg−1. Postoperative care was on the Paediatric Intensive Care Unit (PICU) or Spinal High Dependency Unit (HDU). The anaesthetic chart and cell salvage audit form recorded intra‐operative blood loss. The PICU/HDU charts recorded postoperative drain blood loss for the first 24 h. Aprotinin was given as a bolus prior to the start of surgery followed by an infusion until wound closure. Cost data for allogeneic blood products, autologous blood collection/processing and aprotinin were collected from the start of surgery until 24 h postoperatively. The analysis used current tariffs. Other consumables and drugs were excluded. Comparisons between groups were made using unpaired t tests.

Results  A total of 27 patients were reviewed. Fifteen patients received aprotinin and 12 did not. Intra‐operative cell salvage was used for all patients. Two thirds of the patients in each group were at high risk of major blood loss due to neuro‐muscular disease. The groups (aprotinin versus no aprotinin) were comparable for age (mean ± SD) 13 ± 2.8 versus 14 ± 2.7 years, weight 50.9 ± 16.9 versus 51.2 ± 30.4 kg, surgical time 254 ± 58.8 versus 286 ± 109.6 min and vertebral levels fused (median + interquartile range) 15 (10–16) versus 14.5 (8.5–16). Mean aprotinin bolus dose was 21.14 ± 10.91 kiU kg−1 and mean aprotinin infusion rate was 7.17 ± 2.44 kiU kg−1 h−1. The median transfusion‐related cost of aprotinin was £638.02 (£319.73–£1010.60) compared to £1086.00 (£423.42–£1476.01)(P = 0.107) without aprotinin, equating to a relative cost saving of 41.2%. Total peri‐operative blood loss (as a fraction of EBV), in the aprotinin group was 0.66 ± 0.40 EBV versus 1.25 ± 1.06 EBV(P = 0.09). Median units of blood product transfused in the aprotinin and no aprotinin groups were; blood 1 ( 0–2.5) versus 2.5 (1–5.25) (P = 0.06), fresh frozen plasma 2 (1–2.5) versus 2 (2.3–3.25) (P = 0.07), cryoprecipitate bags 0 (0–0) versus 0 (0–2) (P = 0.16), platelets 0 (nil given) versus 0 (0–1) (P = 0.07).

Conclusions  The reduction in peri‐operative blood loss and thus transfusion requirements associated with aprotinin has translated to a cost reduction. A small sample size has prevented the cost analysis from reaching statistical significance. As blood products become more scarce and costly, blood preservation techniques will become increasingly vital.
P12 An Audit of Fresh Frozen Plasma Transfusion Use in the Royal Hospitals Trust (RGHT)
Authors: Atkinson S.
Published: September 2006

Allogeneic fresh frozen plasma (FFP) transfusions have increased in recent years, in the Royal Group of Hospitals Trust and in the UK as a whole. In the 2003 Serious Hazards of Transfusion report, FFP was the blood product most commonly attributed to the development of transfusion associated acute lung injury and a leading cause of transfusion related mortality. In the British Committee for Standards in Haematology (BCSH) guidelines there are few indications for FFP transfusion. Stainsby found that appropriateness of FFP transfusion in England varied from 62–92%.

Audit objectives (i) To assess the appropriateness of FFP transfusions in the RGHT against BCSH guidelines ‐ 100% standard; and (ii) To assess the adequacy of documentation for FFP transfusion episodes re indication for transfusion and clinical effectiveness ‐ 100% standard.

Method Data relating to FFP transfusion episodes between October 2004 and January 2005 inclusive, was extracted retrospectively from available patient notes by an SpR in haematology and a consultant anaesthetist. Anonymously completed proformas were jointly assessed for appropriateness of transfusion by the same investigators.

FFP transfusion episodes
Appropriate
Inappropriate

137 episodes (114 patients)
93 (68%)
44 (32%)

Reversal of warfarin effect, bleeding not severe or absent

16

Hepatic disease induced coagulopathy, no bleeding

6

Heparin/antiplatelet induced coagulopathy, with bleeding

4

Other causes of coagulopathy without bleeding

13

Ongoing blood loss, normal coagulation screen

4

Normal coagulation screen, no evidence of bleeding

1

Clinical documentation
Present
Absent

Statement re indication for FFP transfusion
73 (53%)
64 (47%)

Statement re clinical effectiveness of transfusion
52 (38%)
85 (62%)

Conclusion and Recommendations A significant number of FFP transfusions are inappropriate, based on recent BCSH guidance. Documentation in clinical notes concerning the indication and response to FFP transfusion is frequently lacking. Appropriateness of FFP transfusion and associated clinical documentation should be improved by staff education and greater awareness of BCSH guidelines. Education should also include appropriate monitoring and management of bleeding secondary to warfarin or antiplatelet therapy. FFP transfusions should be re‐audited 1 year hence. Guidelines for the use of fresh‐frozen plasma, cryoprecipitate and cryosupernatant. The British Society for Haematology 2004, 126: 11–28 Stainsby D. Audit of the Appropriate Use of Fresh Frozen Plasma, National Blood Service, May 2002.
P16 What is the Best Way to Achieve Sustained Changes in Transfusion Prescribing Behaviour by Physicians?
Authors: Hyde C. , Stanworth S. J. , Murphy M. , Brunskill S. , Stearn B. , Howell C.
Published: September 2006

Background and Aim  Many different forms of behavioural interventions continue to be undertaken by UK hospitals and blood transfusion services to change transfusion practice, including adoption and dissemination of guidelines, retrospective and prospective audit, educational events and algorithms or IT linked prescribing modules (such as based in hospital blood banks). But how much do we know about their effectiveness and how best to achieve sustained change in transfusion practice.

Method  The currently available evidence on effectiveness of alternative methods of behaviour change was identified, based on our current methods (Systematic Reviews Initiative, NBS ‐Oxford) for selecting and appraising the evidence base for a focused question.

Results  There are several systematic reviews published by the Effective Practice and Organisation of Care Group of the Cochrane Collaboration. Two recent systematic reviews specifically examined the most rigorous research on changing behaviour in transfusion practice (1,2). These emphasise that, although there is evidence to support a positive effect of interventions, the existing research is limited in amount and generally poor in quality. Long‐term outcomes were rarely examined. The effectiveness and cost‐effectiveness of one approach relative to another is virtually unexplored.

Conclusions  Further robust and higher quality research on this topic is essential. A framework for the most plausible approach to change transfusion behaviour, selecting the right intervention to overcome any perceived barriers to changes in practice, is critical, including to identify those comparisons most likely to yield both meaningful and sustained results.

1. Tinmouth A, MacDougall L, Fergusson D, Amin M, Graham ID, Hebert P & Wilson K. (2005) Reducing the amount of blood transfused. Arch Int Med;165, 845–852.

2. Wilson K, MacDougall L, Fergusson D, Graham I, Tinmouth A, & Hebert P. (2002) The effectiveness of interventions to reduce physician's levels of inappropriate transfusion: what can be learned from a systematic review of the literature. Transfusion;42, 1224–1229.
P21 Therapeutic Efficacy of Plasmapheresis for the Treatment of Refractory Pruritis of Primary Billiary Cirrhosis: 2 Case Reports.
Authors: Mathur K. , McGarvey M. , Taylor S. , Sinclair J. , Lawrie J. , McPhelim A. , Douglas K.
Published: September 2006

Primary billiary cirrhosis (PBC), a chronic cholestatic disease of presumed autoimmune aetiology, is characterised by progressive intrahepatic bile duct destruction, liver cirrhosis, failure, and death, unless treated by liver transplantation. Distressing pruritis (skin itch), fatigue and metabolic bone diseases frequently complicate this disease, significantly reducing quality of life. The pathogenesis of pruritis remains uncertain. Some unknown pruritogen(s) produced by the liver have been implicated which accumulate in the plasma as a result of chronic cholestasis. Recent evidence also suggests a central mechanism, with increased neurotransmission/neuromodulation mediated by endogenous opioid agonists. Therapeutic interventions include unabsorbable oral resins, urso‐deoxycholeic acid, opiate antagonists and rifampicin. More experimental therapies include: partial diversion of bile; charcoal haemoperfusion; UVA; plasmapheresis and albumin‐based dialysis (for patients with renal impairment). We used plasma exchange for the treatment of intractable pruritis in two patients with primary billiary cirrhosis. Both were females between ages of 50–60 years, refractory to all medical treatments and severely disabled by intractable pruritis and fatigue. In the first patient, weekly to fortnightly plasmapheresis considerably reduced the intensity of itch and stabilized her condition until her liver transplant. The second patient was treated for a relapse of PBC following her liver transplant. She significantly improved with more than 50% reduction in the intensity of her generalized itch with healing of excoriations, and was able to sleep for 4 h undisturbed after only one procedure. We suggest that plasmapheresis may be helpful for the pruritis of chronic cholestasis refractory to medical management. It could also be considered for the initial treatment of selected patients in combination with other therapies.
P22 Immunohematologic Monitoring and Blood Component Support in a Major ABO Mismatch Allogeneic Peripheral Blood Stem Cell Transplant Recipient
Authors: Verma A. , Sinha S. , Chaudhary R. , Ray V.
Published: September 2006

Background  Close clinical and immunohematologic monitoring is essential in ABO mismatch peripheral blood stem cell transplantation (PBSCT) in order to anticipate potential complications and to plan appropriate blood component support throughout the disease course.

Case Report  We describe here a first case of a ABO incompatible PBSCT from our center‐ a 19‐year‐old male patient of aplastic anemia (O Rh positive) who had a successful HLA matched but major ABO mismatch PBSCT from his sibling donor (A Rh positive). On admission patient's hemoglobin (Hb) was 4.7 g dL−1, platelet count (PC) 12 × 109 L−1, total leukocyte count (TLC) 2 × 109 L−1. Patient was typed as O Rh positive with negative direct coombs test (DCT) and IgM isohemagglutinin anti‐A titer‐512 and anti‐B‐512. In the pretransplant period total number of blood components (recipient type) transfused were 35, 1, and 10 random donor platelets (RDP), single donor platelets (SDP) and packed red cells (PRBC) respectively. On day of transplant patient had Hb 9 g dL−1, PC 20 × 109 L−1, TLC 2.6 × 109 L−1, IgM anti‐A‐32, anti‐B‐16 (due to immunosuppressive regimen) and negative direct and indirect coombs tests (ICT). Adequate dose of peripheral blood stem cells harvested from donor by a continuous cell separator was infused to patient as per the institute protocol. Engraftment occurred on 12th day of transplant. During these 12 days patient received a total of four PRBC (recipient type) and 8, 3 units of RDP and SDP (stem cell donor type) respectively. After the engraftment patient's laboratory parameters were Hb 8.2 g dL−1, PC 40 × 109 L−1, TLC 5 × 109 L−1. Patient received very few transfusions after the engraftment and was discharged with Hb of 9.2 g dL−1, PC 146 × 109 L−1, TLC 10.9 × 109 L−1 and with blood group still O Rh positive. Post‐transplant immunohematological workup was done on a weekly basis for first 3 weeks and then on each outpatient visit. On follow up DCT showed mixed field reaction from 1st week till 3rd week post transplant, which became negative by 9th week. ABO cell grouping changed from O to A and thus a cell‐serum discrepancy was noted by 9th week (cell group A Rh positive and serum group O) and by 16th week his blood group finally changed to A Rh positive with IgM anti‐A‐undetectable, IgM anti‐B‐512 along with negative DCT. Throughout the disease course the patient received irradiated blood to avoid transfusion‐associated graft‐versus‐host disease.

Conclusion  Our patient had uneventful course with appropriate component support and immunohematologic monitoring during and after the transplant and ABO incompatible stem cell could be transplanted without negative outcome on stem cell engraftment.
P26 Learnbloodtransfusion E‐Learning ‐ Offering a Flexible Resource for Transfusion Training in England and North Wales
Authors: Thompson C. L. , Howell C. A.
Published: September 2006

The Health Service Circular 2002/009: Better Blood Transfusion ‐ Appropriate Use of Blood highlights the essential need to provide transfusion education to all staff involved in the transfusion process. Hospitals have made significant progress to ensure transfusion training is in place. This activity has largely been co‐ordinated by the role of the Transfusion Practitioner. However some staff groups and clinical areas remain difficult to access. In the Serious Hazards of Transfusion (SHOT) report 2004, SHOT recommend the e‐learning package ‘Learnbloodtransfusion’ (LBT). In an attempt to offer the opportunity to provide a blended approach to education and compliment existing training initiatives, the National Blood Service, with support from the National Blood Transfusion Committee purchased an access agreement from the Scottish National Blood Transfusion Service to provide access to the package and the On‐line Recording and Assessment System (ORAS) to hospitals in England and North Wales. A pilot commenced in June 2005 and included five NHS hospitals and one private hospital. Nominated administrators from these sites attended a workshop to better understand the features of and how to use the package. The pilot sites utilised LBT for a period of 3 months and were asked to record any challenges to implementation, difficulties utilising the package and any tips for implementation. Pilot sites completed evaluation forms and attended an evaluation meeting September 2005. Following feedback changes were made to the supportive documentation provided and the implementation process. In November 2005 the package and ORAS were launched in England and North Wales. Feedback from the pilot process showed the main challenge for hospitals was how to establish e‐learning as an integral part of transfusion education within their organisation. Since the purchase of the access agreement and launch of the LBT package, 119 organisations have expressed an initial interest in the package. 33 organisations have gone on to fully implement the package. For 17 further organisations the implementation process is ongoing. The learnbloodtransfusion e‐learning package provides a flexible, free, easy to utilise, evidence based education tool for hospitals to use to supplement existing programmes for transfusion training.
P27 Gathering evidence for BCSH FMH guidelines ‐ counting controversies in FMH
Authors: White J. L. , Milkins C. E. , Rowley M. R. , Lubenko A.
Published: September 2006

The BCSH guidelines for FMH first published in 1999 are now being updated. Evidence on which some of the recommendations are made is being re‐examined, e.g. the number of cells to be counted using the acid elution method (AE), to identify and quantify fetal bleeds. When using flow cytometry (FC) to measure FMH, the guidelines recommend that 500,000 events be collected, based on the statistics of rare event analysis where the CV% of the method decreases with the number of events collected (see Fig. 1). Extrapolating this statistical principle to acid elution (1 in 1000 ‘event’ equates to a 2.4ml bleed using Mollison's formula), where counting 6000 adult cells for FMH quantification is currently recommended, the CV% would be approximately 60 for a 4ml bleed. However this can be improved to approx. 25 if 10,000 cells are counted.

image

[
 CV% (y‐axis) vs number of events counted (x‐axis) for a Poisson distribution where approx. 1 in 1000 positive events is expected. ]

These statistics can also be applied to screening by FMH, where identification of bleeds >4ml is essential since the most commonly used post‐natal dose of anti‐D immunoglobulin (500 i.u.) covers a 4mL bleed. When scanning 25 low power fields (lpf) using x10 objective and x10 eyepiece, a minimum of 50,000 cells are screened (based on data from Mollison and UK NEQAS). The inter‐laboratory CV% = 38 for bleeds of 2 ‐ 6ml (by AE) in UK NEQAS exercises and the CV% according to rare event statistics is approximately 20. These figures can be used to predict the range of FMH values observed at different bleed volumes (see table), using the formula SD = (CV x mean) / 100 and where the expected bleed volume is the mean.

mL FMH
Expected range of FMH (mL) at 95% confidence (=2SD)

CV% 20 (rare event)
CV% = 38 (UK NEQAS)

4
2.4–5.6
1.0–7.0

2
1.2–2.8
0.5–3.5

Theoretically, 2ml is a safer trigger for quantification and follow‐up, since with a 4ml ‘cut‐off’ there is a risk that FMH of >4ml will not be recognised on screening 25 lpf, even where proficiency is good. Also, given the predicted high CV% for quantification by AE, the guidelines will recommend referral of bleeds >2ml for FC and instigation of follow‐up, even where the standard anti‐D dose exceeds 500 i.u.
P03 The Effect of Apheresis on the Donors’ Platelets
Authors: Garner S. F. , Jones C. I. , Angenent W. , Bernard A. , Carr P. , Rankin A. , Stephens J. , Tom B. D. , Walton J. , Dudbridge F. , Ouwehand W. H. , Goodall A. H.
Published: September 2006

Introduction  Many studies have investigated the effects of donation processes on the activation state of platelet concentrates. Apheresis platelets are often found to be the least activated products. However, little is known about the immediate or long‐term effects of frequent apheresis on donors’ platelets. This question was addressed in a cohort of donors in the BLOODOMICS research project, comprising 157 whole blood donors who had donated twice on average (range 1–4), and 349 apheresis donors with an average of 10 donations (range 1–25), in the previous year.

Method  The activation status of the platelets in the donors was determined from the percentage on platelets with bound fibrinogen, by whole‐blood flow cytometry. The immediate effect of apheresis on circulating platelets was studied in 10 donors in samples taken from the arm, pre and post donation, measuring platelet‐bound fibrinogen in unstimulated blood samples and in response to in vitro stimulation with ADP (10‐7M). The long‐term effect of apheresis was assessed by measuring fibrinogen binding to platelets in unstimulated blood, and in response to ADP (10‐7M) and cross‐linked collagen related peptide (XL‐CRP, 0.1μg/mL) activation prior to donation.

Results  Apheresis did not have a consistent immediate effect on resting platelet activation: pre‐donation bound fibrinogen levels ranged from 2.69–7.63% positive platelets (mean 4.41%) and post donation levels ranged from 1.46–9.66% (mean 4.71) (p=0.71). ADP induced fibrinogen binding levels ranged from 11.6–41.4% (mean 30.7%) prior to donation and decreased post donation in 8/10 cases, with values ranging from 6.74–43.6% (mean 23.45%) (p=0.024). The long‐term effect of apheresis was assessed by comparing the results of apheresis and whole blood donors. For all donors resting bound fibrinogen levels ranged from 0.51% to 6.96% positive, with no significant difference between the whole blood and apheresis donors (p=0.69). Responses to ADP did not differ between the two groups, but the apheresis donors showed a 4.01±1.8% (P=0.03) increase in fibrinogen binding in response to XL‐CRP.

Conclusion  Apheresis does not lead to short‐ or long‐term platelet activation. However, prior to donation, apheresis donors show slightly higher responses to XL‐CRP than whole blood donors. This may reflect an increase in circulating younger, more active platelets.
P30 Removal of the Endogenous TSE Infectivity From Blood Using PRDT TSE Affinity Resin And Integration Of The Resin Into The Macopharma P‐CAPT™ Filter
Authors: Rohwer R. G. , Gregori L. , Gurgel P. V. , Lathrop J. T. , Edwardson P. , Lambert B.C. , Carbonell R.G. , Burton S. J. , Hammond D. J.
Published: September 2006

Background  To date, there have been three transfusion transmitted cases of vCJD among 19 recipients that are known to have received blood from persons that later died of vCJD and lived long enough themselves to have developed detectable disease. This is a transmission rate of ∼15%. A survey of surgically removed tissues concluded that the number of incubating cases of vCJD in the UK was at least 4000. Seven percent of this group would on average be blood donors.

Methods  Pathogen Removal and Diagnostics Technologies (PRDT) screened millions of compounds to obtain high affinity ligands to prion protein. A group of ligands were challenged with scrapie infected hamster brain homogenate mixed with a unit of leucoreduced human RBC. Infectivity of the challenge and the unbound were compared. To test for removal of the endogenous blood TSE infectivity, blood from scrapie infected hamsters was collected, leucoreduced and passed through the resin. Whole blood, leucoreduced blood and resin flow‐through samples were titered by the limiting dilution method. A total of 5 ml of each sample was inoculated in 50 μl aliquots into 100 hamsters. The experiment was terminated at 540 days and the brain of every animal was checked for evidence of prion amyloid.

Results  The best resins reduced the titer of the brain‐derived spike into RBC of 107 ID50/ml by over 4 log10ID50, far exceeding the capacity needed to capture endogenous RBC infectivity. To address the uncertainty about the relevance of brain‐derived spikes, the lead resin was also assessed for its ability to remove the infectivity endogenously present in blood. There were no infections among the 100 hamsters inoculated with the resin treated blood. The resin removed > 1.2 log10ID of relevant TSE blood infectivity. The resin has been incorporated by MacoPharma into the P‐CAPTTM filter, a stand alone device for removing TSE infectivity from leucoreduced red blood cells.

Conclusions  PRDT's lead resin adsorbs high concentrations (107 ID50/ml) of brain derived TSE infectivity with high efficiency (4 log10ID50) even in the presence of RBC, and removes the low concentrations (10 ID/ml) of endogenous infectivity that is present in leucoreduced whole blood to the limit of detection (>1.2 log10ID). Implemented as the Macopharma P‐CAPTTM filter it should significantly reduce the risk of transmission of vCJD by blood and blood products.
P36 A Novel RhD Variant
Authors: Tilley L. , Bullock T. , Mason R. , Poole J. , Daniels G.
Published: September 2006

Introduction  Variants of the RhD antigen are often categorised into weak D and partial D phenotypes, although the distinction between the two groups is unclear. One frequently used definition is the ability to make alloanti‐D in partial D, but not in weak D phenotypes, however some phenotypes characterised as weak D are now known to be associated with alloanti‐D production. On a molecular level, weak D phenotypes usually possess RHD mutations encoding amino acid subsitutions within the cytoplasmic or membrane spanning regions of RhD, whilst partial D phenotypes result from changes in the extracellular loops. Thus, weak D red cells could be regarded as having all epitopes of D, but expressed weakly, whilst partial D cells lack some D epitopes. We investigated the red cells of a black pregnant woman because of aberrant reactions obtained in routine D typing, in order to decide if prophylactic anti‐D should be given.

Methods  Routine anti‐D sera and a reagent anti‐D panel were tested serologically by their recommended techniques. Genomic DNA was extracted from whole blood and subjected to sequencing of exons 1 to 9 of the RHD gene.

Results and treatment  The Rh phenotype of the patient was C‐ c+, E‐, e+, V+, VS+. Anti‐D reagents gave variable reactions and a novel pattern of reactions was seen with an anti‐D panel. Sequencing analysis revealed a single G>A mutation at position 490, within exon 4 of the RHD gene, resulting in an Aspartate to Asparagine change at position 164 of the RhD protein (D164N). This appears to be a novel RHD mutation. The patient received prophylactic anti‐D antenatally and at delivery. The maternal antibody screen and Kliehauer screen were negative and she delivered a full term D+ DAT negative infant.

Conclusions  A novel D variant has been identified with an D164N mutation, predicted to lie within the third extracellular loop of the RhD protein. We propose to call this D variant DDN. The molecular basis of this novel phenotype suggests that this could be categorised as a partial D , as the mutation results in a loss of D epitopes. This would be expected to result in the ability to produce alloanti‐D although alloanti‐D production was not reported in this case.
P37 Molecular and Serologic Characterization of RhD Status
Authors: Catherwood M. , Curran M. C. , Wylie J. , Daniels G. , Martin P. , Morris K.
Published: September 2006

Introduction  Developments in technology and knowledge have allowed the elucidation of many of the blood group systems at the molecular level, much of this work is still mainly confined to larger centres and reference facilities. The D antigen is highly complex and of enormous clinical significance causing both haemolytic disease of the newborn and haemolytic transfusion reactions. D typing is routinely performed using serological techniques but examples of weakened expression can be difficult to resolve. Molecular techniques have permitted a greater understanding of these problems and can also be applied to predicting the D type of the foetus using a maternal sample which has obvious benefits to mother and baby.

Aims  The development of a molecular method for RhD typing and compare this to serological typing.

Study Design and Methods  Multiplex PCR was used to analyze RhD status in DNA from 127 randomly selected blood donors from the Northern Ireland Blood Transfusion Service. This method was compared to the serological assessment of RhD typing using the Ortho AutoVueTM System.

Results  Serological results showed that 93 samples (73%) were RhD+ and 34 (27%) were RhD− which is expected for a Caucasian population. 75 samples (50%) were RhC+ and 52 (41%) were RhC−. 111 samples (87%) were Rhc+ and 16 (13%) were Rhc−. Positive and negative molecular results were compared to the corresponding serological results. A concordance rate of 78.7% existed for the comparison of both methods for RhD status. 65.4% of samples were concordant for both methods when assessing RhC status. The concordance rate was 73.2% for Rhc.

Conclusion  We describe a multiplex PCR method for the assessment of RhD status and compare this to results obtained using standard serology. Further development of this molecular method is required to obtain a higher concordance rate. Molecular typing has potential future benefits, along with serological methods, in adding to our understanding of the Rh blood system and identifying RhD variants.
P38 An Acute Hemolytic Transfusion Reaction Due to Anti‐Wra Antibodies.
Authors: Cherian G. , Search S. , Thomas E. , Davies S. V. , Massey E.
Published: September 2006

The Wra antigen is found on the red blood cells of approximately 1 : 1000 caucasians. Anti‐Wra antibodies have been reported to be present in 1 : 25 to 1 : 100 healthy blood donors and an even higher proportion of hospital patients. Wra incompatibilty might therefore be expected to occur in approximately one in 50,000 blood transfusions. Reports of hemolytic transfusion reactions (HTR) and hemolytic disease of the newborn (HDN) due to anti‐Wra are however rare. We report an acute HTR due to anti‐ Wra in a 58 year old male with MDS associated with rigors, shortness of breath and a significant rise in serum bilirubin from 16 μmol L−1 pre‐transfusion to 110 μmol L−1 immediately afterwards. This was accompanied by the appearance of bilirubin and urobilinogen in his urine and a fall in haemoglobin of nearly 2 g dL−1 following the transfusion. Anti‐ Wra was the only antibody implicated. Wra antigen expressing reference panel cells and the unit being transfused during the gave 2–3+ reactions by IAT against the recipient's plasma. The donation typed as positive with Wra antisera. The recipient typed as Wra antigen negative. The reaction resulted in the patient being admitted to hospital for 2 days. The increasing use of electronic issue may result in more frequent reports of reactions due to anti‐Wra as commonly used screening cells do not express this antigen.
P41 Anti‐Cra , Pegnancy and Transfusion Support
Authors: Win N. , Needs M.
Published: September 2006

The managemet of a patient with anti‐Cra presents a challenge as it is impossible to locate Cr(a‐) blood from the UK donors. The data regarding haemolytic transfusion reactions (HTR) in association with anti‐Cra is very flimsy. Patients with anti‐Cra have been transfused with Cr(a+) blood uneventfully, some have provided Cr(a‐) units when red cell survival studies demonstrated shorten survival. UK guidelines (Daniels et al) recommended that weak Cr antibodies are not considered clinically significant, and Cr(a‐) blood is not indicated. There is no firm evidence that anti‐Cra causes HTR, but has been suggested to provide Cr(a‐) units for those with strong antibodies. Anti‐Cra is unique as the antibody may diminish or even disappear during the course of the pregnancy. Weber et al have demonstrated that the decrease in anti‐Cra during pregnancy is due to sequestration by the placenta. This protects the fetus from developing HDN. There were only four reported cases of anti‐Cra during pregnancy. We report our experience in planning transfusion support for a pregnant patient with anti‐Cra. Anti‐Cra (IAT titre 32) was identified in the booking sample of a 31‐year‐old Somalian woman. Her blood typed as O,R1R1 At 28 weeks gestation antibody titre dropped to four. Plan for transfusion support was discussed with the obstetricians. Previous pregnancies were uneventful and the patient did not require any transfusion. In view of the significant drop in antibody level, instead of searching for rare Cr(a‐) blood, we advised transfusing group O, R1R1, K‐ rbcs if the patient required a transfusion. It was planned to deliver by vaginal route. The patient was seen again at 35 weeks gestation. By that time, the IAT titre had further dropped to 1. The healthy baby was delivered by vaginal route during the weekend. There was no clinical evidence of HDN. Delivery was uneventful and the mother did not require blood transfusion. Both the mother and baby were discharged the next day. Attempts to obtain cord and post delivery infant's sample was unsuccessful. Anti‐Cra has not been reported causing HDN, therefore the patient with anti‐Cra does not require close monitoring.The purpose of the serial antibody titration study in our case is to demonstrate the drop or disappearance of antibody. This assisted in making a final decision for selection of suitable blood for the patient.
P42 A Simple Test for the Differential of Maternal and Fetal Bloods
Authors: Thomas E.
Published: September 2006

The structure of fetal haemoglobin (HbF) differs to that of adult haemoglobin (HbA) and protects it from denaturing when subjected to a pH change. With this knowledge, Apt et al1 adjusted the pH of the meconium, in melena neonatorium, by the addition of NaOH, and noted that a change of colour to green from pink occurred only if HbA was present. By utilising the same principle, the process can be modified to confirm the source of blood samples requested for the investigation of a possible fetomaternal haemorrhage, post delivery, for the prevention of Rhesus haemolytic disease of the newborn. 10 adult male bloods and six cord samples were used as the test material for the investigation. The rate at which the colour changed from pink to green of the test material was measured over a range of variables. The haematicrit was artificially adjusted between 30% and packed cells, with a permutation of volumes from 10 to 500 μL added to NaOH at concentrations between 0.05 M and 3 M.

Results The optimum NaOH concentration was 0.1 M, equating to a pH 13.0 The haematicrit showed no influence on the reaction, but packed cells were chosen as the easiest to reproduce for consistency. The rate of colour change from pink to green took a maximum 1 min. Contamination of maternal with fetal bloods, and visa versa, at a low ratio is undetectable and at a high ratio gives a visual chimera of colour and intact erythrocytes.

Method Using the above data a simple routine laboratory method of adding 100 μL of packed cells to 0.5 mL of 0.1 M NaOH, rapid mixing, and observing for a colour change between 1 min and a maximum of 10 mins. Pink to green show the blood to maternal i.e. HbA, but remaining pink indicative of HbF. The simultaneous testing of blood from and adult male and known cord blood, provides a positive and negative control respectively. This simple test has been extensively used to verify which are maternal and cord samples, when both express the same ABO and Rh(D) blood groups.

1. Apt L, Downey WS Jr. (1953) Melena neonatorium: the swallowed‐blood syndrome. AMA Am J Dis Child.; 86(5): 639; discussion, 639–40.
P43 Extension of the Hospital Transfusion Team to Include a Transfusion Auditor Improves the Quality of Clinical Transfusion Medicine Whilst Proving Self‐funding in Our Organisation.
Authors: Johnson J. , Goudie K. J. , Hall R. L.
Published: September 2006

The introduction of a local Hospital Transfusion Committee in 1999 allowed the Transfusion Laboratory the opportunity to present levels of red cell use to clinicians. This information was easily obtained from the laboratory information system, and the data presented in the form of league tables by individual Consultant and their medical speciality. Agreement was obtained for the league tables to be published via global electronic mail every quarter, and natural competition contributed to an immediate reduction in red cell use within our organisation. The blood and blood product budget is held by the Transfusion Laboratory, hence the laboratory was able to utilise the financial savings generated by the reduction in red cell use to fund a 0.2 whole time equivalent Transfusion Auditor, based in the Transfusion Laboratory but performing extensive audit on behalf of the Hospital Transfusion Team/Committee. The role has allowed blood use by clinician, anaesthetist, infusion location and diagnosis to be audited, the results being examined by the Hospital Transfusion Committee, and recommendations for change in practice made to the clinicians involved. The process has saved over £500,000 since its introduction, facilitated improved clinical Transfusion Medicine, reduced clinical risk, and funded alternatives to homologous red cell transfusions, near patient testing devices, rapid infuser's and theatre equipment designed to keep patient's warm during major surgery. Concurrently the cost of wastage of red cells and platelets has been reduced from £30,000 per annum in 1999 to £14,630 in 2005. In spite of an 11.5% increase in clinical activity, red cell use in our district general hospital has been reduced by 30% from 13,605 units per annum in 1999 to 9551 in 2005. The Transfusion Auditor post is now established in our organisation and continues to prove self‐funding whilst facilitating improved clinical Transfusion Medicine.
P46 Sharing Information Via a Regional Web Site
Authors: Cotton S. , Hearnshaw K. , Qureshi H. , Prangnell D. , Bailey C.
Published: September 2006

The Trent Regional Transfusion Committee (RTC) identified that communication of information and best practice was a priority following feedback from an education day for hospital transfusion teams in July 2005. At this time there was no route of communication to the hospital transfusion teams other than via the RTC members. An RTC ‘newsletter sub‐group’, co‐ordinated by the NBS regional hospital liaison team, was established to produce a newsletter which was sent to members of hospital transfusion teams in the region. This was effective in providing information about the RTC, its members and its purpose. However the communication was one way and limited to the frequency of the production of newsletters. A further RTC ‘web‐site sub‐group’ was established and included multidisciplinary membership from the Trent region. A regional web‐site was developed and hosted by United Lincolnshire Hospitals NHS Trust. The web site is accessible to hospital transfusion teams in the region and contains information regarding meetings, presentations, and regional initiatives together with a database of documents. The sub‐groups of the RTC and members of hospital transfusion teams send information to the web master for inclusion on the web‐site. The web‐site was launched in June 2006 http://www.trtc.nhs.uk and a survey was conducted with members of the hospital transfusion teams to assess improvement in communication within the region. The survey has concluded that sharing of information and best practice has improved within the region. The web‐site will be further developed and will have links to other web‐sites and useful documents. This has been a successful project for the RTC, meeting local need and supporting networking between hospital trusts within the Trent region.
P51 Variation in the Ex Vivo Response to LPS Stimulation in Healthy Volunteers: Identification of Extremes of Monocyte Function
Authors: Farrugia R. , Garner S. F. , Gray E. , Watkins N. A. , Goodall A. H. , Ouwehand W. H.
Published: September 2006

Introduction  Numerous epidemiological and clinical studies have established a firm link between infection, the inflammatory response and cardiovascular disease. Furthermore, it is known that individuals differ in their responses to immune stimuli such as Lipopolysaccharide (LPS) that stimulates monocytes through Toll‐like receptor 4 (TLR4). In this study we set out to identify healthy individuals with extremes of monocyte response to LPS stimulation. Once identified these individuals will be studied further to identify genes responsible for the observed differences.

Methods  Small volumes of whole blood from 208 healthy blood donors were incubated with 0, 1 or 5 ng mL−1E. coli LPS for 4 hr at 37°C. Cell free plasma was collected both pre‐ and post‐incubation and the production of the pro‐inflammatory cytokine IL‐6 measured by ELISA. In addition, TaqMan genotyping was performed on two TLR4 SNPs, (rs4986790 and rs4986791, encoding D299G and T399I respectively) to determine whether these SNPs correlated with the observed functional responses.

Results  The range of IL‐6 produced was 0–26 ng mL−1 in response to 1 ng mL−1 LPS, and 2–56 ng mL−1 in response to 5 ng mL−1 LPS. Frequency distributions of IL‐6 levels show one‐tailed distributions for both stimuli with more outlying high extremes than low extremes. Quality control assays showed that both inter‐ and intra‐assay variability had a CV <10% and that the response correlates weakly with monocyte counts. Furthermore, repeat testing on 20 individuals demonstrated that the response to LPS is reproducible over time. No correlation was observed between TLR4 genotype and IL‐6 production following LPS stimulation.

Conclusions  Our stimulation results demonstrate that there is substantial inter‐individual variation in response to both 1 ng mL−1 and 5 ng mL−1 doses of LPS. We now have identified a number of individuals with either a high or low response to LPS stimulation. These individuals will be recalled for further functional testing and gene expression profiling to identify differences between the two extremes of monocyte function.
P53 Electron Microscopical Localisation of CD61 (Beta3 Integrin) on Placental Syncytiotrophoblast Microvilli
Authors: Kumpel B. , Jackson D. , Sibley K. , White G.
Published: September 2006

Introduction  Neonatal alloimmune thrombocytopenia (NAIT) due to maternal antibodies to the human platelet antigen (HPA)‐1a can occur in first pregnancies. The HPA‐1 polymorphism is located on platelet glycoprotein (GP)IIIa (CD61, beta3 integrin). It is hypothesised that besides fetal platelets, an additional source of fetal CD61 could cause alloimmunisation early in pregnancy. CD61 was earlier identified on placental villous trophoblasts by immunocytochemistry.

Methods  Whole‐mount immuno‐electron microscopy was used to study the ultrastructural localisation of CD61 on placental tissue. Fragments of first trimester (n = 5, 8–12 weeks gestational age) and term (n = 1) placental chorionic villi were incubated with anti‐CD61 or IgG1 isotype control, washed, incubated with 18 nm colloidal gold‐conjugated anti‐mouse IgG, washed, fixed in phosphate‐buffered glutaraldehyde and processed through to embedding in epoxy resin. 100 nm sections were prepared from the EM blocks; these were stained with uranyl acetate and lead citrate, and examined with a Phillips CM10 electron microscope. Positive control was term tissue stained with anti‐placental alkaline phosphatase (PLAP).

Results  Microvilli were observed on the apical membrane of some but not all of the villous syncytiotrophoblast (STB) surfaces. Formation of this brush border occurs during the first trimester to increase the surface area of these cells for optimal transfer of nutrients and gases from the adjacent maternal blood to the fetus. All specimens had some microvilli. After staining with anti‐CD61, gold particles were present on and between some microvilli of all specimens, either singly or in small groups. Stronger staining with more frequent occurrence of groups of gold particles was evident on microvilli of the term tissue incubated with anti‐PLAP. No gold particles were seen on the isotype control specimens.

Conclusion  From early on in pregnancy, CD61 is present on the surface of fetal STB in contact with maternal blood. This protein carrying the HPA‐1 polymorphism might be the cause of the initial immunising event that leads to NAIT.
P55 The Management of Blood Samples to be Used in Assessing Tests for vCJD in Donor Blood.
Authors: Pelle B.
Published: September 2006

There are presently 161 reported cases of vCJD in the UK, with three cases associated with the receipt of blood components. However, there is currently no routine large‐scale screening test for vCJD in humans. The NHSBT considers that it is essential to be in a position to validate emerging tests for vCJD as quickly as possible, to ensure that suitable tests can be implemented in a timely manner, if required by the DoH. NHSBT is proactively preparing a panel of samples that will be used in assessing tests, to determine if they are operationally fit for purpose. This work is being undertaken in a specifically designed Test Assessment Facility (TAF) at Manchester Blood Centre, which went live in November 2005. To manage the panel, the Thermo Nautilus Laboratory Information Management System (LIMS) has been installed. Nautilus is a highly configurable LIMS, capable of handling large amounts of data. Irreversible anonymisation, integration with robotic equipment, and the ability to interrogate other data systems and retrieve information, are key features. Whole blood donations are received into the TAF and are logged into the LIMS, which retrieves basic donor demographic information, then irreversibly anonymises it. Red cell, buffy coat and plasma components are then prepared, and robot sample handlers sub‐aliquot them. The LIMS then references a data output file, and processes the sub‐aliquot information, creating a detailed inventory. Wireless technology is used for plate storage. The LIMS underwent extensive validation, including the use of designated test scripts to challenge and validate all aspects of the system, plus verification of compliance with GMP and GAMP regulations. The panel builds at a rate of around 125 donations per week, equating to 18,000 individual sub‐aliquots, all managed by the LIMS. The panel will take 2 years to complete, when it will consist of samples from 10,000 donations(5000 from UK donors and 5000 from US donors), producing a panel size of 1,440,000 sub‐aliquots. The use of Nautilus LIMS in the TAF has proved invaluable to the project, and has contributed to its successful implementation. Furthermore, it will continue to manage the panel, and all associated activities.
P56 Platelet Screening by Bactalert Prior to Issue ‐ Limited Sensitivity Revealed by Residual Rate of Contamination in Outdated Screened Units.
Authors: Doherty C. , Foley M. , Salami A. , Cadden E. , Coakley P. , Murphy W. G.
Published: September 2006

Introduction and Methods  Since November 2004 we have tested all platelets for bacterial contamination prior to release. Platelets are stored for a minimum of 12 h at 22 oC after manufacture, and a 7.5–10 ml sample is then inoculated into an aerobic BacTAlert bottle, and a similar volume into an anaerobic bottle. (For the first 10 months an 8 mL inoculum in aerobic culture only was used.) All units stored to expiry are retested using a 10 mL aerobic sample and a 10 mL anaerobic sample on BacTAlert. Confirmed positive is a positive result on BacTAlert, a positive subculture from the BacTAlert bottle, and a further culture of the same species from the platelet unit, or for pools, from the pool or from one other component from the donations used in the pool. False positive is a positive signal from the bottle, but no organism detected on subculture, Gram stain, and re‐culture of the unit. Unconfirmed positive is a positive subculture or Gram stain from the bottle but no residual material available for culture, or all residual material negative on culture. Since November 2005 we have extended the shelf life of Gambro Trima apheresis platelets on the basis of a retest at day 4; platelets still in stock on day 4 of storage have a repeat aerobic and anaerobic culture performed, and are returned to stock with a extra two days of shelf life.

Results  In total 30,751 platelet units have been screened prior to issue. There were 12 confirmed and 16 non‐confirmed positives on the initial test, for a total positive rate of 0.09%. 13/9213 (0.14%) were from apheresis collections; 15/21538 (0.07%) were from pools of four buffy coats after 22oC overnight hold of the whole blood units (95% confidence interval for the difference in positive rate = 0.0%–0.2%, i.e. statistically significantly different). 5651/30,751 expired unused and were retested: there were 12 positives ‐ five confirmed and seven non‐confirmed, for a total positive rate of 0.21% (12/5651). This is not statistically significantly different from the initial test rate (95% confidence interval for the difference is −0.003–0.000). All day four tests for extending shelf life (n = 1293) were negative. There were 14 isolates of coagulase negative staphylococci, 11 of P acnes, three of bacillus spp, and two of diphtheroids among the 40 positive units.

Conclusions  Screening platelets for bacteria prior to issue using relatively large sample volumes to increase detection rates has a limited sensitivity in the order of 50%.

Apheresis platelets are more likely to be contaminated after collection than platelets manufactured from pooled buffy coats made from whole blood units stored overnight at 22oC.

Using a day four retest for extending platelet shelf life is a practicable approach to the problem of low initial sensitivity of bacterial screening.