Expected individual benefit of prophylactic platelet transfusions in hemato-oncology patients based on bleeding risks

Background: Prophylactic platelet transfusions prevent bleeding in hematooncology patients, but it is unclear how any benefit varies between patients. Our aim was to assess if patients with different baseline risks for bleeding benefit differently from a prophylactic platelet transfusion strategy. Study design and methods: Using the data from the randomized controlled TOPPS trial (Trial of Platelet Prophylaxis), we developed a prediction model for World Health Organization grades 2, 3, and 4 bleeding risk (defined as at least one bleeding episode in a 30 days period) and grouped patients in four risk-quartiles based on this predicted baseline risk. Predictors in the model were baseline platelet count, age, diagnosis, disease modifying treatment, disease status, previous stem cell transplantation, and the randomization arm. Results: The model had a c-statistic of 0.58 (95% confidence interval [CI] 0.54– 0.64). There was little variation in predicted risks (quartiles 46%, 47%, and 51%), but prophylactic platelet transfusions gave a risk reduction in all risk quartiles. The absolute risk difference (ARD) was 3.4% (CI 12.2 to 18.9) in the lowest risk quartile (quartile 1), 7.4% (95% CI 8.4 to 23.3) in quartile 2, 6.8% (95% CI 9.1 to 22.9) in quartile 3, and 12.8% (CI 3.1 to 28.7) in the highest risk quartile (quartile 4). Conclusion: In our study, generally accepted bleeding risk predictors had limited predictive power (expressed by the low c-statistic), and, given the wide confidence intervals of predicted ARD, could not aid in identifying subgroups of patients who might benefit more (or less) from prophylactic platelet transfusionClinical epidemiolog

Dynamic prediction of bleeding risk in thrombocytopenic preterm neonates

Clinical epidemiolog

Thrombocytopenia and the effect of platelet transfusions on the occurrence of intracranial hemorrhage in patients with acute leukemia - a nested case-control study

We designed a study to describe the incidence of intracranial hemorrhage according to severity and duration of thrombocytopenia and to quantify the associations of platelet transfusions with intracranial hemorrhage in patients with acute leukemia. In this case-control study nested in a cohort of 859 leukemia patients, cases (n = 17) were patients diagnosed with intracranial hemorrhage who were matched with control patients (n = 55). We documented platelet counts and transfusions for seven days before the intracranial hemorrhage in cases and in a "matched" week for control patients. Three measures of platelet count exposure were assessed in four potentially important time periods before hemorrhage. Among these leukemia patients, we observed the cumulative incidence of intracranial hemorrhage of 3.5%. Low platelet counts were, especially in the three to seven days preceding intracranial hemorrhage, associated with the incidence of intracranial hemorrhage, although with wide confidence intervals. Platelet transfusions during the week preceding the hemorrhage were associated with higher incidences of intracranial hemorrhage; rate ratios (95% confidence interval) for one or two platelet transfusions and for more than two transfusions compared with none were 4.04 (0.73 to 22.27) and 8.91 (1.53 to 51.73) respectively. Thus, among acute leukemia patients, the risk of intracranial hemorrhage was higher among patients with low platelet counts and after receiving more platelet transfusions. Especially, the latter is likely due to clinical factors leading to increased transfusion needs.Clinical epidemiolog

Clinical value of early assessment of hyperfibrinolysis by rotational thromboelastometry during postpartum hemorrhage for the prediction of severity of bleeding: a multicenter prospective cohort study in the Netherlands

Introduction: Coagulopathy may be the result of hyperfibrinolysis and could exacerbate bleeding following childbirth. Timely recognition of hyperfibrinolysis during the earliest stages of postpartum hemorrhage could identify women at risk of more severe blood loss who may benefit from targeted anti-fibrinolytic therapy. Rotational thromboelastometry (ROTEM (R)) is a point-of-care test that could detect hyperfibrinolysis. The aim of this study was to evaluate whether early assessment of hyperfibrinolysis by ROTEM during postpartum hemorrhage could predict progression to severe postpartum hemorrhage.Material and methods: During a prospective cohort study in the Netherlands among women with postpartum hemorrhage (total blood loss at least 1000 ml within 24 h after childbirth) ROTEM measurements were performed following 800-1500 ml of blood loss. Hyperfibrinolysis was defined as an enzymatic fibrinolysis index (ROTEM EXTEM maximum clot lysis [ML] minus the ROTEM APTEM ML) above 15%. Severe postpartum hemorrhage was defined as a composite end point of total blood loss greater than 2000 ml, transfusion of four or more units of packed cells, and/or need for an invasive intervention. The predictive value of hyperfibrinolysis for progression to severe postpartum hemorrhage was assessed by area under the receiver operating curve ( AUC) and positive and negative predictive values.Trial registration: ClinicalTrials. gov (NCT02149472).Results: Of 390 women included, 82 (21%) had severe postpartum hemorrhage. Four (1%) women had thromboelastometric evidence of hyperfibrinolysis, of whom two developed severe postpartum hemorrhage. The AUC for enzymatic fibrinolysis index more than 15% for progression to severe postpartum hemorrhage was 0.47 (95% CI 0.40-0.54). Positive and negative predictive values for this index were 50.0% (95% CI 6.8-93.2) and 79.3% (95% CI 74.9-83.2), respectively.Conclusions: Thromboelastometric evidence of hyperfibrinolysis was rare in women with postpartum hemorrhage when assessed between 800 and 1500 ml of blood loss. The clinical predictive value of viscoelastometric point-of-care testing for hyperfibrinolysis for progression to severe postpartum hemorrhage during early postpartum hemorrhage is limited.Clinical epidemiolog

Association of Timing of Plasma Transfusion With Adverse Maternal Outcomes in Women With Persistent Postpartum Hemorrhage

IMPORTANCE Early plasma transfusion for women with severe postpartum hemorrhage (PPH) is recommended to prevent coagulopathy. However, there is no comparative, quantitative evidence on the association of early plasma transfusion with maternal outcomes. OBJECTIVE To compare the incidence of adverse maternal outcomes among women who received plasma during the first 60 minutes of persistent PPH vs women who did not receive plasma for similarly severe persistent PPH. DESIGN, SETTING, AND PARTICIPANTS This multicenter cohort study used a consecutive sample of women with persistent PPH, defined as PPH refractory to first-line measures to control bleeding, between January 1, 2011, and January 1, 2013. Time-dependent propensity score matching was used to select women who received plasma during the first 60 minutes of persistent PPH and match each of them with a woman who had shown the same severity and received the same treatment of PPH but who had not received plasma at the moment of matching. Transfusions were not guided by coagulation tests. Statistical analysis was performed from June 2018 to June 2019. EXPOSURES Transfusion of plasma during the first 60 minutes of persistent PPH vs no or later plasma transfusion. MAIN OUTCOMES AND MEASURES Incidence of adverse maternal outcomes, defined as a composite of death, hysterectomy, or arterial embolization. RESULTS This study included 1216 women (mean [SD] age, 31.6 [5.0] years) with persistent PPH, of whom 932 (76.6%) delivered vaginally and 780 (64.1%) had PPH caused by uterine atony. Seven women (0.6%) died because of PPH, 62 women (5.1%) had a hysterectomy, and 159 women (13.1%) had arterial embolizations. Among women who received plasma during the first 60 minutes of persistent PPH, 114 women could be matched with a comparable woman who had not received plasma at the moment of matching. The incidence of adverse maternal outcomes was similar between the women, with adverse outcomes recorded in 24 women (21.2%) who received early plasma transfusion and 23 women (19.9%) who did not receive early plasma transfusion (odds ratio, 1.09; 95% CI, 0.57-2.09). Results of sensitivity analyses were comparable to the primary results. CONCLUSIONS AND RELEVANCE In this cohort study, initiation of plasma transfusion during the first 60 minutes of persistent PPH was not associated with adverse maternal outcomes compared with no or later plasma transfusion, independent of severity of PPH

Transition from fresh frozen plasma to solvent/detergent plasma in the Netherlands: comparing clinical use and transfusion reaction risks

Plasma transfusion is indicated for replenishment of coagulative pro- teins to stop or prevent bleeding. In 2014, the Netherlands switched from using similar to 300mL fresh frozen plasma (FFP) units to using 200mL Omniplasma, a solvent/detergent treated pooled plasma (SD plasma), units. We evaluated the effect of the introduction of SD plasma on clinical plasma use, associated bleeding, and transfusion reaction incidences. Using diagnostic data from six Dutch hospitals, national blood bank data, and national hemovigilance data for 2011 to 2017, we compared the plasma/red blood cell (RBC) units ratio (f) and the mean number of plasma and RBC units transfused for FFP (similar to 300mL) and SD plasma (200mL) for various patient groups, and calculated odds ratios comparing their associated transfusion reaction risks. Analyzing 13,910 transfusion episodes, the difference (Delta f = f(SD) (-) f(FFP)) in mean plasma/RBC ratio (f) was negligible (Delta f(entire-cohort) = 0.01 [95% confidence interval (CI): -0.02 - 0.05]; P=0.48). SD plasma was associated with fewer RBC units transfused per episode in gynecological (difference of mean number of units -1.66 [95% CI: -2.72, -0.61]) and aneurysm (-0.97 [-1.59, -0.35]) patients. SD plasma was further associated with fewer anaphylactic reactions than FFP (odds ratio 0.37 [0.18, 0.77; P<0.01]) while the differences for most transfusion reactions were not statistically significant. SD plasma units, despite being one third smaller in volume than FFP units, are not associated with a higher plasma/RBC ratio. SD plasma is associated with fewer anaphylactic reactions than FFP plasma/RBC units ratio.Clinical epidemiolog

Coagulation parameters during the course of severe postpartum hemorrhage: a nationwide retrospective cohort study

Research into fetal development and medicin

Clinical value of early viscoelastometric point-of-care testing during postpartum hemorrhage for the prediction of severity of bleeding: a multicenter prospective cohort study in the Netherlands

Introduction To evaluate rotational fibrin-based thromboelastometry (ROTEM(R) FIBTEM) with amplitude of clot firmness at 5 min (A5) as an early point-of-care parameter for predicting progression to severe postpartum hemorrhage, and compare its predictive value with that of fibrinogen.Material and methods Prospective cohort study in the Netherlands including women with 800-1500 ml of blood loss within 24 h following birth. Blood loss was quantitatively measured by weighing blood-soaked items and using a fluid collector bag in the operating room. Both FIBTEM A5 values and fibrinogen concentrations (Clauss method) were measured between 800 and 1500 ml of blood loss. Predictive accuracy of both biomarkers for the progression to severe postpartum hemorrhage was measured by area under the receiver operating curves (AUC). Severe postpartum hemorrhage was defined as a composite endpoint of (1) total blood loss >2000 ml, (2) transfusion of >= 4 packed cells, and/or (3) need for an invasive intervention to cease bleeding.Results Of the 391 women included, 72 (18%) developed severe postpartum hemorrhage. Median (IQR) volume of blood loss at blood sampling was 1100 ml (1000-1300) with a median (interquartile range [IQR]) fibrinogen concentration of 3.9 g/L (3.4-4.6) and FIBTEM A5 value of 17 mm (13-20). The AUC for progression to severe postpartum hemorrhage was 0.53 (95% confidence interval [CI] 0.46-0.61) for FIBTEM A5 and 0.58 (95% CI 0.50-0.65) for fibrinogen. Positive predictive values for progression to severe postpartum hemorrhage for FIBTEM A5 <= 12 mm was 22.5% (95% CI 14-33) and 50% (95% CI 25-75) for fibrinogen <= 2 g/L.Conclusions The predictive value of FIBTEM A5 compared to fibrinogen concentrations measured between 800 and 1500 ml of blood loss following childbirth was poor to discriminate between women with and without progression towards severe postpartum hemorrhage.Research into fetal development and medicin

The bright and the dark side of blood transfusion : turning data into knowledge

C. Caram-Deelder’s thesis explores the potential of secondary data – data that was generated for a different purpose than the research itself - to answer questions regarding safety and efficacy of blood products. By combining datasets of several hospitals, she demonstrated that receiving red cell transfusions from a female donor who has been pregnant is associated with increased mortality among male patients under the age of 50. Also using data from hospitals she demonstrated that old platelets shorter the time between platelets transfusions, resulting in an increased total number of transfusions on a population level. This increase is, however, unlikely to outweigh the benefit of reduced outdating and wastage. By meta-analysing studies it is shown that old platelets are inferior to fresh platelets for platelet related counts, time between transfusions and the need of additional platelet transfusions. Additionally the thesis discusses the methodological issue of the use of the terms ‘prospective’ and ‘retrospective’ in clinical observational research. These terms are still broadly used in spite of the recommendation to refrain from using them by guidelines and journals’ editorial boards. The usage of the terms was, however, not associated with the quality of the report. </p

The bright and the dark side of blood transfusion : turning data into knowledge

C. Caram-Deelder’s thesis explores the potential of secondary data – data that was generated for a different purpose than the research itself - to answer questions regarding safety and efficacy of blood products. By combining datasets of several hospitals, she demonstrated that receiving red cell transfusions from a female donor who has been pregnant is associated with increased mortality among male patients under the age of 50. Also using data from hospitals she demonstrated that old platelets shorter the time between platelets transfusions, resulting in an increased total number of transfusions on a population level. This increase is, however, unlikely to outweigh the benefit of reduced outdating and wastage. By meta-analysing studies it is shown that old platelets are inferior to fresh platelets for platelet related counts, time between transfusions and the need of additional platelet transfusions. Additionally the thesis discusses the methodological issue of the use of the terms ‘prospective’ and ‘retrospective’ in clinical observational research. These terms are still broadly used in spite of the recommendation to refrain from using them by guidelines and journals’ editorial boards. The usage of the terms was, however, not associated with the quality of the report. LUMC / Geneeskund