Platelet Transfusion Policy Research Articles

Patient-tailored platelet transfusion practices for children supported by extracorporeal membrane oxygenation.

Extracorporeal membrane oxygenation (ECMO) serves as cardiopulmonary therapy in critically ill patients with respiratory/heart failure and often necessitates multiple blood product transfusions. The administration of platelet transfusions during ECMO is triggered by the presence or risk of significant bleeding. Most paediatric ECMO programmes follow guidelines that recommend a platelet transfusion threshold of 80-100 × 109/L. To reduce exposure to platelets, we developed a practice to dynamically lower the threshold to ~20 × 109/L. We describe our experience with patient-tailored platelet thresholds and related bleeding outcomes. We retrospectively evaluated our platelet transfusion policy, bleeding complications and patient outcome in 229 ECMO-supported paediatric patients in our unit. We found that more than 97.4% of patients had a platelet count <100 × 109/L at some point during their ECMO course. Platelets were transfused only on 28.5% of ECMO days; and 19.2% of patients never required a platelet transfusion. The median lowest platelet count in children who had bleeding events was 25 × 109/L as compared to 33 × 109/L in children who did not bleed (p < 0.001). Our patients received fewer platelet transfusions and did not require more red blood cell transfusions, nor did they experience more haemorrhagic complications. We have shown that a restrictive, 'patient-tailored' rather than 'goal-directed' platelet transfusion policy is feasible and safe, which can greatly reduce the use of platelet products. Although there was a difference in the lowest platelet counts in children who bled versus those who did not, the median counts were much lower than current recommendations.

Transfusion policy in pediatric extracorporeal membrane oxygenation patients: Less could be more.

To evaluate a restrictive transfusion policy of red blood cells (RBC) and platelets in pediatric patients submitted to extracorporeal membrane oxygenation (ECMO). Retrospective descriptive study of pediatric patients supported with ECMO, from January 2010 to December 2019. Hemoglobin, platelet, lactate and mixed venous oxygen saturation (SvO2) values of each patient while on ECMO, were collected. Transfusion efficiency and tissue oxygenation were statistically evaluated comparing pre-transfusion hemoglobin, lactate and SvO2 with post-transfusion values. Ranges of hemoglobin and platelets were established, and the number of transfusions registered. The bleeding complications and outcome were documented. Of a total of 1016 hemoglobin values, the mean value before transfusion was 8.6g/dl. Hemoglobin and SvO2 increased significantly post-transfusion. Red blood cell transfusion varied with hemoglobin values: when hemoglobin value was less than 7g/dl, 89% (41/46) were transfused but just 23% (181/794) when greater or equal to 7g/dl. In the presence of active bleeding, the frequency of RBC transfusion increased from 32% to 62%, with hemoglobin between 7g/dl and 8g/dl.The mean value for platelet transfusion was 32 x 109/L. Thirty-eight (43%) platelet values between 20 x 109/L and 30x109/L, and 31 (40%) between 30 x 109/L and 40 x 109/L led to platelet transfusion; between 40 x 109/L and 50 x 109/L, only 7 (9%) prompted platelet transfusion.Comparing the 2010-2015 to 2016-2019 periods there was a decrease in RBC and platelet transfusion threshold with similar survival (p = .528). Survival to discharge was 68%. Using a restrictive RBC and platelet transfusion policy was safe and allowed a good outcome in this case series. The presence of active bleeding was an important decision factor when hemoglobin was above 7g/dl and platelets were above 30 x 109/L.

Особенности вязко-эластических свойств сгустка крови и проявления геморрагического синдрома при тромбоцитопении у онкогематологических больных

Введение. Тромбоцитопения является частым осложнением онкогематологических заболеваний, которое провоцирует развитие геморрагического синдрома. Уровень тромбоцитов в периферической крови, являющийся пороговым для переливания концентрата тромбоцитов (КТ), окончательно не установлен. Применение тромбоэластографии (ТЭГ) при тромбоцитопениях у онкогематологических больных может повысить прогностические возможности определения риска кровотечений. Цель исследования: оценить вязко-эластические свой ства сгустка крови при тромбоцитопении менее 50×109/л и их взаимосвязь с проявлениями геморрагического синдрома у онкогематологических больных. Материалы и методы. В исследование включено 84 пациента с гемобластозами и тромбоцитопенией менее 50×109/л, 54 (64%) мужчины и 30 (36%) женщин, медиана возраста — 54 года. В зависимости от уровня тромбоцитов в периферической крови пациентов разделили на 2 группы: группа 1 — 44 пациента с числом тромбоцитов от 25 до 50×109/л, группа 2 — 40 больных с содержанием тромбоцитов менее 25×109/л. Исследовали показатели периферической крови, коагулограммы и ТЭГ. Степень тяжести кровотечений оценивали по шкале проявлений геморрагического синдрома (ВОЗ) и по шкале оценки побочных явлений Национального института рака (США). Результаты. Гипокоагуляция по ТЭГ в группе 1 выявлена в 46% случаев, в группе 2 — в 75%. Значимые межгрупповые различия показателей ТЭГ получены только в отношении максимальной амплитуды. Геморрагический синдром в группе 1 диагностирован у 6 (13%) пациентов, в группе 2 — у 14 (35%). Однако предиктивная роль влияния количества тромбоцитов на частоту развития геморрагического синдрома не установлена (β = 0,016; p = 0,92). Сочетание тромбоцитопении и гипокоагуляции по ТЭГ проявлялось в виде геморрагического синдрома в 3,3 раза чаще, чем без гипокоагуляции (RR = 3,3; 95% ДИ = 1,20–9,05). В ряде случаев основанная на результатах ТЭГ трансфузионная тактика позволила избежать переливания КТ при инвазивных манипуляциях у больных с тромбоцитопенией менее 25 × 109 / л. Заключение. Глубина тромбоцитопении не является надежным предиктором геморрагического синдрома. Применение ТЭГ у пациентов с тромбоцитопенией позволяет оптимизировать трансфузионную тактику, избежав ненужных переливаний КТ. Сочетание тяжелой тромбоцитопении с гипокоагуляцией по данным ТЭГ служит показанием для профилактических трансфузий КТ. Background. Thrombocytopenia is a frequent complication of hemoblastosis that causes hemorrhagic syndrome. The threshold of peripheral blood platelet count for transfusion of platelet concentrate is discussed. Thromboelastography (TEG) can be considered as additional prognostic method for bleeding risk assessment in thrombocytopenic patients with leukemia. Objectives: to study changes in the viscoelastic properties of blood clot in hemoblastosis patients with thrombocytopenia less than 50×109/L and their relationship with the manifestations of hemorrhagic syndrome. Patients/ Methods. The study included 84 hemoblastosis patients — 54 (64%) men и 30 (36%) women with thrombocytopenia less than 50 × 109/L, median age — 54 years. All patients are divided into 2 groups according to the platelet count: Group 1 — 25–50×109/L, Group 2 — less than 25×109/L. Peri pheral blood counts, TEG and coagulogram parameters were evaluated in both groups. Manifestations of hemorrhagic syndrome were assessed according to the WHO bleeding scale and Common terminology criteria for adverse events of the National Cancer Institute (USA). Results. Hypocoagulation according TEG in Group 1 was found in 46% of cases, in Group 2 — in 75%. Significant intergroup differences in TEG parameters were obtained only in maximum amplitude. Hemorrhagic syndrome in Group 1 diagnosed in 6 (14%) patients, in Group 2 — in 14 (35%). There was no dependence of hemorrhagic syndrome frequency on the severity of thrombocytopenia (β = 0.016; p = 0.92). The combination of thrombocytopenia and hypocoagulation according TEG manifested as a hemorrhagic syndrome 3.3 times more often than without hypocoagulation (RR = 3.3; 95% CI = 1.20–9.05). In some cases, TEG-based transfusion tactics allowed to avoid unnecessary platelet concentrate transfusion during invasive procedures in patients with thrombocytopenia less than 25 × 109/L. Conclusions. Severity of platelet depletion is not accuracy predictor for hemorrhagic events. Use of TEG in patients with thrombocytopenia allows to optimize the transfusion tactics and to avoid unnecessary platelet concentrate transfusions. The combination of severe thrombocytopenia with hypocoagulation according TEG serves as indication for prophylactic platelet concentrate transfusion.

Management of bleeding in palliative care patients in the general internal medicine ward: a systematic review.

BackgroundPalliative care patients, those suffering from at least one chronic lifelong medical condition and hospice care patients, those with a life expectancy less than 6 months, are regularly hospitalised in general internal medicine wards. By means of a clinical case, this review aims to equip the internist with an approach to bleeding in this population. Firstly, practical advice on platelet transfusions will be provided. Secondly, the management of bleeding in site-specific situations will be addressed (from the ENT/pulmonary sphere, gastrointestinal - urogenital tract and cutaneous ulcers). Finally, an algorithm pertaining to the management of catastrophic bleeding is proposed.MethodsElectronic databases, including EMBASE, Pubmed, Google Scholar and the Cochrane Library were studied as primary resources, in association with local guidelines, to identify papers exploring platelet transfusions and alternative management of site-specific bleeding in palliative care patients.ResultsHaemorrhagic complications are frequent in palliative care patients in the internal medicine ward. Current guidelines propose a therapeutic-only platelet transfusion policy. Nonetheless, prophylactic and/or therapeutic transfusion remains a physician-dependent decision. Site-specific therapeutic options are based on expert opinion and case reports. While invasive measures may be pertinent in certain situations, their application must be compatible with patient goals. Catastrophic bleeding requires caregivers' comforting presence; pharmacological management is secondary.ConclusionLiterature is lacking regarding management of bleeding in the palliative care population hospitalised in an acute medical setting. Recommendations are of limited quality, the majority based on case reports or expert opinion. Further studies, exploring for example the impact on patient quality of life, are desirable to improve the management of this frequently encountered complication.

Two Different Platelet Thresholds for Bleeding Prophylaxis in Children with Malignancies or Non-Malignant Disorders: The Bambino Gesù Children's Hospital Experience

Background: Prophylactic platelet transfusion is commonly used to prevent life-threatening bleeding events in patients with severe thrombocytopenia associated with chemotherapy courses or hematopoietic stem cells transplantation (HSCT). In adults, the transfusion threshold for prophylaxis is usually set at 10x109plts/L, but in pediatric setting, it is still a matter of debate. Moreover, evidences from the PLADO trial (Slichter SJ et al. N Engl J Med. 2010) and recommendations form international guidelines (ICTMG, Nahirniak S et al. Transfus Med Rev. 2015) suggest two different platelet doses in Inpatients and Outpatients, but clinical experiences in children are still lacking. Aims: In order to confirm the safety of the recommended transfusion threshold, to test two different platelet doses in hospitalized patients and Outpatient setting and to optimize platelet clinical use, as a Children's Hospital, we applied, starting from January 2018, a new prophylactic platelet transfusion policy. Methods: Platelet dose was calculated based on body-surface area (BSA) of each patient (from age-standardized weight). As suggested by ICTMG, different platelets doses were given to Inpatients and Outpatients: (low-dose) 1.1x1011platelets per square meter (plts/m2) and (medium-dose) 2.2x1011plts/m2, respectively. The transfusion threshold for prophylaxis was set at 10x109plts/L, but higher threshold could be considered as per clinical decision (in presence of bleeding signs or risk factors for major bleeding). Patients with platelets refractoriness and newborns, were excluded from our study. Only major bleeding events (grade 3 or higher according to World Health Organization criteria) were collected during the study period. Results: From January 2018 to June 2019, 15278 platelet pediatric aliquots were transfused in our Hospital. Of all the aliquots, 8876 (58.1%) were obtained from apheresis procedures and 6402 (41.9%) from buffy-coat-derived pooled platelet concentrates. Almost 77% (11751) of the all aliquots were transfused in patients with onco-hematologic diseases. Among these, 9771 (64.0%) in the Inpatient group (N=547) and 1980 (13.0%) in the Outpatient group (N=385). Between Inpatients, 6794 (44.5%) aliquots were transfused in Onco-Hematology Ward and 2977 (19.5%) in the HSCT unit. During the study period, only 10 major bleeding events were observed. No fatal hemorrhagic episode was recorded and all of the bleedings occurred in hospitalized patients, and accounted for almost 2% of this population. Intracranial bleeding accounted for five out of six grade 4 bleeding episodes, and occurred in two patients with acute myelogenous leukemia, in one patient with Hodgkin lymphoma and in two patients with advance neuroblastoma. The other grade 4 bleeding event was a massive peritoneal and pleuric hemorrhage with a life-threatening haemodinamic instability in a patient with acute lymphoblastic leukemia (the main characteristics of these patients are reported in the table). Conclusions: our results show that a platelet transfusion policy based on recommendation mainly developed in adults may be safely applied also to pediatric patients with cancer or receiving HSCT. In fact, the lower dose used in Inpatient group resulted in a grade 4 bleeding rate similar to that observed in the PLADO trial (1.0% vs 0.7%). The double dose transfused in Oupatients was effective in preventing major bleeding events. Table. Disclosures No relevant conflicts of interest to declare.

Comparison of a therapeutic-only versus prophylactic platelet transfusion policy for people with congenital or acquired bone marrow failure disorders.

This is the protocol for a review and there is no abstract. The objectives are as follows: To compare a therapeutic-only versus prophylactic platelet transfusion policy for people with myelodysplasia, inherited or acquired aplastic anaemia, and other congenital bone marrow failure disorders.

Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Comparison of different platelet count thresholds to guide administration of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Different doses of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Different doses of prophylactic platelet transfusion for preventing bleeding in people with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

A therapeutic-only versus prophylactic platelet transfusion strategy for preventing bleeding in patients with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

A therapeutic-only versus prophylactic platelet transfusion strategy for preventing bleeding in patients with haematological disorders after myelosuppressive chemotherapy or stem cell transplantation.

Current trends in platelet transfusions practice: The role of ABO-RhD and human leukocyte antigen incompatibility.

Platelet transfusions have contributed to the revolutionary modern treatment of hypoproliferative thrombocytopenia. Despite the long-term application of platelet transfusion in therapeutics, all aspects of their optimal use (i.e., in cases of ABO and/or Rh (D incompatibility) have not been definitively determined yet. We reviewed the available data on transfusion practices and outcome in ABO and RhD incompatibility and platelet refractoriness due to anti-human leukocyte antigen (HLA) antibodies. Transfusion of platelets with major ABO-incompatibility is related to reduced posttransfusion platelet (PLT) count increments, compared to ABO-identical and minor, but still are equally effective in preventing clinical bleeding. ABO-minor incompatible transfusions pose the risk of an acute hemolytic reaction of the recipient that is not always related to high anti-A, B donor titers. ABO-identical PLT transfusion seems to be the most effective and safest therapeutic strategy. Exclusive ABO-identical platelet transfusion policy could be feasible, but alternative approaches could facilitate platelet inventory management. Transfusion of platelets from RhD positive donors to RhD negative patients is considered to be effective and safe though is associated with low rate of anti-D alloimmunization due to contaminating red blood cells. The prevention of D alloimmunization is recommended only for women of childbearing age. HLA alloimmunization is a major cause of platelet refractoriness. Managing patients with refractoriness with cross-matched or HLA-matched platelets is the current practice although data are still lacking for the efficacy of this practice in terms of clinical outcome. Leukoreduction contributes to the reduction of both HLA and anti-D alloimmunization.

Prophylactic platelet transfusions in patients with blood malignancies: cost analysis of a randomized trial.

This cost analysis uses data from a randomized trial comparing a no prophylaxis versus prophylactic platelet (PLT) transfusion policy (counts <10 × 10(9) /L) in adult patients with hematologic malignancies. Results are presented for all patients and separately for autologous hematopoietic stem cell transplantation (HSCT) (autoHSCT) and chemotherapy/allogeneic HSCT (chemo/alloHSCT) patients. Data were collected to 30 days on PLT and red blood cell (RBC) transfusions, major bleeds, serious adverse events, critical care, and hematology ward stay. Data were costed using 2011 to 2012 UK unit costs and converted into US$. Sensitivity analyses were performed on uncertain cost variables. Across the whole trial no prophylaxis saved costs compared to prophylaxis: -$1760 per patient (95% confidence interval [CI], -$3250 to -$249; p < 0.05). For autoHSCT patients there was no cost difference between arms: -$110 per patient (95% CI, -$1648 to $1565; p = 0.89). For chemo/alloHSCT patients no prophylaxis cost significantly less than prophylaxis: -$5686 per patient (95% CI, -$8580 to -$2853; p < 0.01). The cost impact of no prophylaxis differed significantly between subgroups. Sensitivity analyses varying daily treatment costs and ward stay for chemo/alloHSCT patients reduced cost differences to -$941 per patient (p = 0.21) across the whole trial and -$2927 per patient (p < 0.05) in chemo/alloHSCT subgroup. It is unclear whether a no-prophylaxis policy saves costs overall. In chemo/alloHSCT patients cost savings are apparent but their magnitude is sensitive to a number of variables and must be considered alongside clinical data showing increased bleeding rates. In autoHSCT patients savings generated through lower PLT use in no-prophylaxis arm were offset by cost increases elsewhere, for example, additional RBC transfusions. Cost-effectiveness analyses of alternative PLT transfusion policies simultaneously considering costs and patient-reported outcomes are warranted.

A therapeutic-only versus prophylactic platelet transfusion strategy for preventing bleeding in patients with haematological disorders after chemotherapy or stem cell transplantation.

This is the protocol for a review and there is no abstract. The objectives are as follows: To determine whether a therapeutic-only platelet transfusion policy (platelet transfusions given when patient bleeds) is as effective and safe as a prophylactic platelet transfusion policy (platelet transfusions given to prevent bleeding usually when the platelet count falls below a given trigger level) in patients with haematological disorders undergoing myelosuppressive chemotherapy or stem cell transplantation.

Therapeutic rather than prophylactic platelet transfusion policy for severe thrombocytopenia during liver transplantation

Platelet transfusion (PTx) has been identified as an important risk factor for morbidity and mortality after liver transplantation (LTx). Our aim was to evaluate the safety of therapeutic rather than prophylactic PTx policy in severe thrombocytopenic patients undergoing LTx. Recipients of LTx were divided into two groups: group I (GI) (n = 76) platelet count (PC) ≥ 50 × 109/l and group II (GII) PC < 50 × 109/l (n = 76). Platelets were transfused following a thromboelastometry protocol and clinical signs of diffuse bleeding. Both groups were compared regarding hemoglobin (Hb), international normalized ratio (INR), fibrinogen level, blood loss (BL), blood products required, percentage of bloodless surgery, duration of mechanical ventilation, ICU stay, and vascular complications. Each group was further subdivided according to PTx into (GI NPTx and GII NPTx) with no platelet transfusion (NPTx) and (GI PTx and GII PTx) received PTx. These subgroups were further compared for some variables. Base line Hb was significantly higher while INR was significantly lower in GI.75% avoided PTx in GII. Comparisons of BL, packed red blood cells (PRBCs), and cryoprecipitate transfusion were insignificant. Fresh frozen plasma (FFP) transfusion was higher and the percentage of bloodless surgery was lower in GII. In GII, PC increased after start of surgery. Two cases of hepatic artery thrombosis in GI and one in GII were recorded. Recovery of platelets was quicker, and duration of mechanical ventilation and ICU stay was shorter in NPTx patients regardless the base line PC. Cut-off values of PC 30 × 109/l (with sensitivity 73.7% and specificity 78.8%, p < 0.01), BL of 3750 ml in GI (sensitivity of 75% and specificity of 69%, p < 0.01) and of 3250 ml in GII (sensitivity of 84.2% and specificity of 87.7% (p < 0.01)) could indicate the need of PTx. With therapeutic approach, 75% of patients in GII could avoid unnecessary PTx with its hazards without excessive bleeding. PC in GII increased intraoperatively, PTx may lead to delayed recovery of platelets, increased duration of mechanical ventilation and ICU stay. The given cut-off values may help to guide PTx.

Prophylactic platelet transfusion for prevention of bleeding in patients with haematological disorders after chemotherapy and stem cell transplantation

Prophylactic platelet transfusion for prevention of bleeding in patients with haematological disorders after chemotherapy and stem cell transplantation

An audit of platelet transfusion within the Wellington Cancer Centre

An audit of platelet transfusion was performed to assess adherence to local prophylactic policy and to assess if therapeutic transfusions were administered in line with international recommendations. A prospective audit of platelet transfusion therapy was conducted at the Wellington Cancer Centre in patients with hypoproliferative thrombocytopenia over a 3-month period from 26 January 2008 to 30 April 2008. There were 398 episodes of evaluable clinical decision activity generated through either platelet counts <50 × 10(9) /L or platelet transfusion events. Each episode was assessed and defined as either adhering to or breaching the local prophylactic platelet transfusion policy. Thrombocytopenia and/or platelet transfusion occurred in 63 patients aged 16-84 years with either a haematological or solid organ malignancy. Decisions to withhold prophylactic platelet transfusion in thrombocytopenic patients adhered to policy for 99% of platelet counts <50 × 10(9) /L. Where transfusions were administered, 77% were prophylactic and 23% were for therapeutic indications. Prophylactic transfusions adhered to policy for 72% of platelet counts <50 × 10(9) /L. Adherence to prophylactic transfusion policy for febrile patients with a threshold of ≤15 × 10(9) /L was 84%, compared to 63% for stable afebrile patients with a threshold of ≤10 × 10(9) /L. Where policy was breached, in 80% of cases the platelet count had not reached the prophylactic transfusion threshold. Of the clinical decisions leading to therapeutic transfusions, 67% were deemed appropriate and predominantly a single adult therapeutic dose of platelets was administered. Where multiple doses of platelets were transfused, 86% of these transfusion events either breached policy or were deemed suboptimal management. The audit demonstrated a high rate of adherence to local transfusion policy. Where policy was breached, predominantly a transfusion had occurred prior to a platelet count reaching the pre-defined trigger. The use of multiple dose platelet transfusions was almost never appropriate. Educating staff in the use of a stringent transfusion policy may lead to reductions in platelet product use.

Influence of Prophylactic Platelet Transfusions on the Recovery of Bone Marrow Function After Intensive Chemotherapy for Acute Myeloid Leukemia.

AbstractAbstract 1118▪ Introduction:Treatment of acute myeloid leukemia (AML) patients (< 65 years) consists of intensive chemotherapy. During the aplastic period after chemotherapy it is common to support the patient with prophylactic platelet transfusions (PT) in order to keep platelet count above 10 × 109/L. However, by some it is questioned if the prophylactic transfusion is necessary and whether a therapeutic platelet transfusion (TT) policy might be sufficient. We studied the effects of the two transfusion policies on number of platelet transfusions, bleeding complications, duration of thrombocytopenia and days of hospital stay in two departments of hematology: one in a large tertiary care hospital (MCL;TT) and the other in an university hospital (UMCG; PT). In both hospitals the same chemotherapy was used for the treatment of AML patients. The first chemotherapy course consists of Ara-C (200 mg/m2/ci, days 1–7) and Idarubicin (12 mg/m2/i.v., days 5,6,7); the second course consists of Ara-C (1000 mg/m2, 3 hrs inf, q 12 hrs × 12, days 1–6) and Amsa (120 mg/m2/i.v. days 3,5,7); some patients received a third course consisting of Mitoxantrone (10 mg/m2/i.v. × 5, days 1–5) and Etoposide (100 mg/m2/i.v. × 5, days 1–5). With PT platelets were transfused if the morning platelet count dropped below 10 × 109/L; in case of TT platelets were transfused when new petechiae developed, clinically relevant bleeding occurred or gastro-intestinal bleeding is suspected. Results:26 patients were treated with 54 chemotherapy courses and received PT; 15 patients, 34 chemotherapy courses received TT. Age was similar in both groups: 50 ± 11 resp 50 ± 12 years. There was no significant difference in the number of different chemotherapy courses between the two groups. 48% of the chemotherapy courses in the PT group consisted of Ara-C/Idarubicin, 44% Ara-C/Amsa en 8% Mitoxantrone /Etoposide, compared to 41% (p=0.7), 38% (p=0.7) and 21% (p=0.1) in the TT group. In the PT group 8,5 ± 5,1 platelet transfusions were used per chemotherapy course compared to 4,2 ± 2,5 in the TT group (p < 0.0001). Bleeding complications occurred significantly more in the TT group. In the TT group 11 bleeding complications were observed in 34 chemotherapy courses: 6 gastro-intestinal bleedings, inconvenient vaginal bleeding in 2 chemotherapy courses, 1 hematuria,1 significant subcutaneous bleeding and 1 cerebral hemorrhage; in the PT group 7 bleeding complications occurred in 54 courses (p=0.03): 5 chemotherapy courses were complicated by vaginal bleedings, 1 retinal bleeding and 1 gastro-intestinal bleeding. Especially gastro-intestinal bleedings occurred significantly more in the TT group: 6/34 courses vs 1/54 courses (p=0.01) in the PT group. Recovery of bone marrow function (absolute neutrophil count > 0.5 × 109/L; platelet count > 20 × 109/L, without platelet transfusions) was reached earlier in the TT group. Absolute neutrophil count > 0.5 × 109/L was noticed 26 ± 12 days after start of chemotherapy in the TT group compared to 32 ± 7 days after start chemotherapy in the PT group (p=0.01). Platelet count > 20 × 109/L without platelet transfusions was seen 21 ± 11 days after start chemotherapy in the TT group compared to 32 ± 13 days in the PT group (p<0.0001). Days in hospital was significantly reduced in the TT group: 29 ± 8 days compared to 38 ± 15 in the PT group (p=0.002). In summary, these data demonstrate that a therapeutic platelet transfusion strategy might lead to a reduced number of platelet transfusions, faster recovery of bone marrow function after chemotherapy and reduced hospital stay. Although manageable, more gastro-intestinal bleedings occurred in this group of patients. Disclosures:No relevant conflicts of interest to declare.

A General Change of the Platelet Transfusion Policy from Apheresis Platelet Concentrates to Pooled Platelet Concentrates is Associated with a Sharp Increase in Donor Exposure and Infection Rates

Background: We compare the actual with the potential donor exposure and possible infection rates in the Hanover Medical School (MHH) platelet (PLT) transfusion recipients if the current MHH standard of apheresis PLT concentrate (A-PC) supply would be replaced by a pooled PLT concentrate (P-PC) transfusion regimen. Donors, Patients, and Methods: The electronic records of the MHH Institute of Transfusion Medicine and the MHH Department of Medical Controlling were evaluated to assess the development of PLT needs and supply at MHH from 2003–2006. For 2006, we evaluated all PLT transfusion recipients with respect to their overall transfusion needs, classified them for low and high PLT transfusion needs, and related them to the diagnostic groups that underlie their PLT demands. We assumed a P-PC preparation procedure using 4 whole blood-derived buffy coats for all calculations for potential donor exposure. To predict the possible infection rates of an unrecognized viral infection with low prevalence in the general population to A-PC or to P-PC recipients and the influence of neutralizing agent specific antibodies (NAB), we established a mathematical contamination/ infection model based on the current PLT transfusion mode and data about GBV-C virus infection among Hanover blood donors. Results: From 2003 to 2006, the 1,300–1,400 persons comprising MHH apheresis donor pool covered a 36% increase in PC transfusions. The exclusive use of P-PCs instead of A-PC would require a total of 36,240–49,276 whole blood donations to meet MHH demands, corresponding to a more than 1 log step increase in donor exposure. For individual hematological patients, the change to P-PCs would imply an 80–125%, for individual surgical patients a 40–50% higher donor exposure. Our infection model revealed an approximately 4 times higher infection. Conclusions: A change to P-PC would imply a more than one log step higher donor exposure, and an unrecognized infection with a prevalence around 1% leads to an up to 4 times higher infection rate. A general change in the PC transfusion policy that favors P-PCs is dangerous and must be avoided.

Severe Acute Hemolytic Transfusion Reaction Following ABO-Mismatched Platelet Transfusion: Should ABO-Mismatched Platelet Transfusion Policy Be Evaluated.

Transfusion of ABO-mismatched platelets is common practice. Although a unit of single donor apheresis platelet (SDP) contains as much plasma and passive anti-A or/and anti-B antibodies (allo-agglutinins) as a unit of fresh frozen plasma, ABO- mismatched platelet transfusions are considered safe and hemolytic transfusion reactions have only rarely been reported. We report a case of a 67-year old male, blood group A, with mantle cell lymphoma who received 1 SDP for chemotherapy induced thrombocytopenia. Several prior platelet transfusions had been uneventful. After 150 ml of irradiated, leukoreduced, SDP from blood group O donor had been infused, he developed nausea, light-headiness, chills, and back pain. He became bradycardic and hypotensive. Platelet transfusion was discontinued and intravenous dexamethasone and rapid saline infusion was administered. Later, his hemoglobin dropped from 10.6 to 7.4 g/dl and total serum bilirubin increased by 9 fold. A direct antiglobulin test (DAT) on post-transfusion sample demonstrated 1+ reactivity at room temperature. An elution test performed on the patient's circulating red blood cells contained anti-A antibodies. These results are consistent with a severe acute hemolytic transfusion reaction. The donor anti-A and anti-B antibodies titers at room temperature and at 37°C were 512 and 2048 with A1 cells and 128 and 256 with B cells, respectively.This case illustrates the rare possibility of hemolytic transfusion reaction occurring as a result of ABO-mismatched platelets from group O donor with high-titer anti-A antibodies. SDP (in contrast to pooled platelets) offers the advantages of reduced risk of infection transmission and alloimmunization by limiting exposure to one donor only. However, it increases the opportunity for hemolytic transfusion reaction to occur if the donor has high-titer antibodies which would have been diluted if pooled platelets were used. As SDP use becomes more widespread, the risk of clinically significant hemolytic reactions is likely to increase, especially in seriously ill patients who tolerate these reactions particularly poorly. Moreover, increasingly, apheresis platelets are being donated by a small group of highly motivated donors, raising the chances of repeated transfusions from the same donors. We propose that the safety of ABO-mismatched platelet transfusions be re-evaluated. Effectiveness (and costs) of potential preventive strategies such as screening all SDP units for high-titer antibodies and/or plasma volume reduction of all mismatched SDP units should be studied.

The frequency of bleeding complications in patients with haematological malignancy following the introduction of a stringent prophylactic platelet transfusion policy : C.R. Callow, R. Swindell, W. Randall, et al. Br J Haematol 118: 677–682, 2002

The frequency of bleeding complications in patients with haematological malignancy following the introduction of a stringent prophylactic platelet transfusion policy : C.R. Callow, R. Swindell, W. Randall, et al. Br J Haematol 118: 677–682, 2002

The frequency of bleeding complications in patients with haematological malignancy following the introduction of a stringent prophylactic platelet transfusion policy.

Indications for platelet transfusion remain controversial and are frequently based on arbitrary numerical criteria. In October 2000, we introduced a stringent prophylactic-platelet transfusion policy < 10 x 109/l for stable patients and < 20 x 10(9)/l in the presence of major bleeding or additional risk factors. A trigger of < 50 x 10(9)/l was introduced for patients undergoing invasive procedures. A prospective analysis was performed measuring the frequency of minor and major bleeding events, morbidity, mortality and duration of pancytopenia. Blood product usage was assessed and health care savings measured. A total of 98 patients were evaluated on 2147 patient study days and 271 bleeding episodes were recorded. Major bleeding occurred on 1.39% (30/2147) of the study days when platelet counts were < 10 x 10(9)/l and 2.3% (50/2147) of the study days when platelet counts were 10-20 x 10(9)/l. In patients with platelets > 20 x 10(9)/l, there were 117 major bleeding episodes observed on 5.4% of the study days. In patients with no identified additional risk factors present, major haemorrhages were recorded in 0.51% (11/2147) of the study days in patients with platelet counts > or = 10 x 10(9)/l . There was a 36% reduction in platelet units transfused compared with retrospective data when an arbitrary transfusion trigger of 20 x 10(9)/l was in place (P = < 0.02). Of note, a 16% reduction in red cell transfusions was recorded. These data confirm that the introduction of a transfusion trigger of < 10 x 10(9)/l in the absence of fresh bleeding and sepsis (> 38 degrees C) is safe and has a significant impact on overall hospital transfusion costs.