Clinical characteristics of women captured by extending the definition of severe postpartum haemorrhage with 'refractoriness to treatment': a cohort study

Background: The absence of a uniform and clinically relevant definition of severe postpartum haemorrhage hampers comparative studies and optimization of clinical management. The concept of persistent postpartum haemorrhage, based on refractoriness to initial first-line treatment, was proposed as an alternative to common definitions that are either based on estimations of blood loss or transfused units of packed red blood cells (RBC). We compared characteristics and outcomes of women with severe postpartum haemorrhage captured by these three types of definitions. Methods: In this large retrospective cohort study in 61 hospitals in the Netherlands we included 1391 consecutive women with postpartum haemorrhage who received either ≥4 units of RBC or a multicomponent transfusion. Clinical characteristics and outcomes of women with severe postpartum haemorrhage defined as persistent postpartum haemorrhage were compared to definitions based on estimated blood loss or transfused units of RBC within 24 h following birth. Adverse maternal outcome was a composite of maternal mortality, hysterectomy, arterial embolisation and intensive care unit admission. Results: One thousand two hundred sixty out of 1391 women (90.6%) with postpartum haemorrhage fulfilled the definition of persistent postpartum haemorrhage. The majority, 820/1260 (65.1%), fulfilled this definition within 1 h following birth, compared to 819/1391 (58.7%) applying the definition of ≥1 L blood loss and 37/845 (4.4%) applying the definition of ≥4 units of RBC. The definition persistent postpartum haemorrhage captured 430/471 adverse maternal outcomes (91.3%), compared to 471/471 (100%) for ≥1 L blood loss and 383/471 (81.3%) for ≥4 units of RBC. Persistent postpartum haemorrhage did not capture all adverse outcomes because of missing data on timing of initial, first-line treatment. Conclusion: The definition persistent postpartum haemo

Performance of the Advia Centaur second generation troponin assay TnI-Ultra compared to the first generation cTnI assay

BACKGROUND: A cardiac troponin concentration above the 99th percentile limit of a reference population is a sensitive marker of myocardial necrosis. Current guidelines require troponin assays to have a total imprecision of <or =10% at the 99th percentile limit. In this study, the Advia Centaur second-generation TnI-Ultra assay was validated and compared with its predecessor the cardiac troponin I (cTnI) assay, with a focus on the current guidelines for diagnosis of acute myocardial damage. METHODS: An imprecision profile of the TnI-Ultra assay was evaluated by analysing different pools over 20 days. The imprecision of the cTnI assay was used as comparison. The reference range was established based on TnI-Ultra analysis in 221 individuals. RESULTS: The cTnI concentration that could be determined with a total imprecision of 10% was 0.05 microg/L for the TnI-Ultra assay and 0.3 microg/L for the cTnI assay. The 99th percentile limit in the distribution of a reference population was 0.06 microg/L as determined with the TnI-Ultra assay. CONCLUSIONS: The TnI-Ultra assay provides significantly improved sensitivity when compared with the cTnI assay and a total imprecision of <or =10% is obtained at the 99th percentile limit of value distribution of a reference population. Using the TnI-Ultra assay, slightly increased cTnI concentration can be detected reliably following the current guidelines

Performance of the Advia Centaur second generation troponin assay TnI-Ultra compared to the first generation cTnI assay

BACKGROUND: A cardiac troponin concentration above the 99th percentile limit of a reference population is a sensitive marker of myocardial necrosis. Current guidelines require troponin assays to have a total imprecision of <or =10% at the 99th percentile limit. In this study, the Advia Centaur second-generation TnI-Ultra assay was validated and compared with its predecessor the cardiac troponin I (cTnI) assay, with a focus on the current guidelines for diagnosis of acute myocardial damage. METHODS: An imprecision profile of the TnI-Ultra assay was evaluated by analysing different pools over 20 days. The imprecision of the cTnI assay was used as comparison. The reference range was established based on TnI-Ultra analysis in 221 individuals. RESULTS: The cTnI concentration that could be determined with a total imprecision of 10% was 0.05 microg/L for the TnI-Ultra assay and 0.3 microg/L for the cTnI assay. The 99th percentile limit in the distribution of a reference population was 0.06 microg/L as determined with the TnI-Ultra assay. CONCLUSIONS: The TnI-Ultra assay provides significantly improved sensitivity when compared with the cTnI assay and a total imprecision of <or =10% is obtained at the 99th percentile limit of value distribution of a reference population. Using the TnI-Ultra assay, slightly increased cTnI concentration can be detected reliably following the current guidelines

Troponin I concentrations in heparinized plasma and serum differ when measured with the Advia Centaur TnI-Ultra assay

Letter to the edito

Blood group genotyping in a multitrauma patient: a case report

Currently DNA-based analysis of blood groups is mainly used to improve transfusion safety by reducing alloantibody formation in multiply transfused patients and by monitoring pregnancies at risk for hemolytic disease of the fetus and newborn. We present a case in which genotyping was performed after massive transfusion with unmatched group O, D- blood in a trauma setting. Our patient was genotyped as O1A1 and predicted to be D-, and we therefore transfused group A, D- red blood cell concentrates. This case demonstrates how the use of blood group genotyping in an acute setting can lead to a decrease in the unnecessary use of group O, D- blood products

Charcot-Leyden crystals in acute myeloid leukemia

Letter to the edito

Evaluation of the Ves-Matic Cube 200 erythrocyte sedimentation method : comparison with Westergren-based methods

The erythrocyte sedimentation rate (ESR) is still a widely used parameter for acute phase inflammation. Recently, new methods based on direct undiluted measurement of ESR in a standard EDTA tube have been developed. We evaluated the analytic performance of one of these new methods, the Ves-Matic Cube 200 (Diesse Diagnostica Senese, Siena, Italy), and compared it with several established Westergren-based diluted methods. The Ves-Matic Cube 200 showed a poor correlation (r = 0.83) with the International Council for Standardization in Haematology Westergren reference method, mainly caused by a considerable negative bias at low ESR levels. Moreover, a random bias was found at higher ESR levels that correlated with hematocrit levels, suggesting a differential influence of packed cell volume on the Ves-Matic Cube 200 results compared with Westergren results. We conclude that the Ves-Matic Cube 200 method is not interchangeable with Westergren-based diluted methods and generates ESR results that are too deviant to be clinically acceptable

Artifact formation due to ethyl thio-incorporation into silylated steroid structures as determined in doping analysis

Trimethylsilylation of target substances in a mixture of N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA), ammonium iodide and ethanethiol is frequently applied for the application of gas chromatography–mass spectrometry (GC–MS) in steroid analysis. However, artifacts were formed when using this mixture to silylate the steroids androsterone and etiocholanolone obtained from a urine matrix. The artifacts were identified as ethyl thio-containing products of the respective trimethylsilyl derivatives. The conversion of the studied products increased slowly as a function of time, was dependent on the presence of the urine matrix and was significantly accelerated by adding diethyl disulfide to the reagent before incubation. Also ethyl thio-incorporation into testosterone and epitestosterone was established. A mechanism for ethyl thio-incorporation is proposed. The conversion achieved after 120-h sample storage at room temperature was insufficient to significantly influence the analysis of androsterone and etiocholanolone under the studied conditions. However, the results provide fundamental insight into the mechanism of silylation and the occurring side-reactions. Moreover, when investigating the formation of new metabolites, the ethyl thio-incorporation can lead to misinterpretation