Avaliação da embebição e do desenvolvimento inicial das estruturas embrionárias de sementes de milho submetidas a diferentes potenciais hídricos

Substrates with water potentials between O and -12atm, were used to evaluate the behavior of corn seeds during the germination process. Water deficiency treatments were compared with the control (adequate available water) using seeds with and without fungicide treatment. The analysis and the interpretation of the results permitted to conclude that the absorption of water, the emergency and the initial development of the embryonic structures are interdependent and vary with the water deficit. For these cases the reduction of water potential promotes difficulties in the evolution of the processes. The presence of fungicide treatment may not influence quantitatively the processes occurring in the beginning of the germination.Empregando substratos com potenciais hídricos variáveis entre 0 e -12atm, o presente trabalho objetivou avaliar o comportamento das sementes de milho postas a germinar. As situações de deficiência hídrica foram diretamente comparadas à testemunha (plena disponibilidade de água), usando sementes com e sem tratamento fungicida. A análise e a interpretação dos resultados permitiram concluir que a absorção de água, a emergência e o desenvolvimento inicial das estruturas embrionárias são interdependentes e reagem no mesmo sentido ao déficit hídrico; para esses casos, a redução do potencial hídrico promove dificuldades na evolução dos processos. Paralelamente, a presença de tratamento fungicida pode não influenciar, quantitativamente, os fenômenos envolvidos no início da germinação

The sensitivity and specificity of rotational thromboelastometry (ROTEM) to detect coagulopathy during moderate and severe postpartum haemorrhage: a prospective observational study

Introduction Point-of-care viscoelastic haemostatic assays such as rotational thromboelastometry (including ROTEM and TEG) have been used in the management of postpartum haemorrhage (PPH). This study compared results obtained from the automated ROTEM Sigma with laboratory tests of coagulation and platelet count during PPH. Methods A prospective observational cohort study recruited women with PPH ≥1000 mL (or clinical concern of bleeding). The Fibtem A5, Extem CT and Pltem (Extem A5 – Fibtem A5) results were compared with laboratory tests of fibrinogen, prothrombin time (PT), activated partial thromboplastin time (APTT) and platelet count. Results 521 women were recruited, including 274/277 (98.9%) of women with PPH ≥1500 mL. Fibtem A5 results were matched with laboratory fibrinogen in 552/644 (85.7%) samples. The incidence of abnormal laboratory results was low: fibrinogen ≤2 g/L 23/464 (5.0%), PT or APTT >1.5 × midpoint of reference range 4/464 (0.9%), and platelet count <75 × 109/L 11/477 (2.3%). Area-under- the-receiver operator characteristic curve for Fibtem A5 to detect fibrinogen ≤2 g/L was 0.96 (95% Confidence Intervals (CI) 0.94 to 0.98, P<0.001), with sensitivity and specificity of Fibtem A5 ≤11 mm to detect fibrinogen ≤2 g/L of 0.76 and 0.96. Prolonged Extem CT results improved after treatment of hypofibrinogenaemia alone. Intervention points for platelet and fresh frozen plasma (FFP) transfusion based on ROTEM Sigma parameters could not be established. Conclusion During PPH (≥1000 mL or cases of clinical concern about bleeding), ROTEM Sigma Fibtem A5 can detect fibrinogen ≤2 g/L and guide targeted fibrinogen replacement. Laboratory results should continue to be used to guide platelet and FFP transfusion

Measurement of blood loss during postpartum haemorrhage

Background We set out to validate the accuracy of gravimetric quantification of blood loss during simulated major postpartum haemorrhage and to evaluate the technique in a consecutive cohort of women experiencing major postpartum haemorrhage. The study took part in a large UK delivery suite over a one-year period. All women who experienced major postpartum haemorrhage were eligible for inclusion. Methods For the validation exercise, in a simulated postpartum haemorrhage scenario using known volumes of artificial blood, the accuracy of gravimetric measurement was compared with visual estimation made by delivery suite staff. In the clinical observation study, the blood volume lost during postpartum haemorrhage was measured gravimetrically according to our routine institutional protocol and was correlated with fall in haemoglobin. The main outcome measure was the accuracy of gravimetric measurement of blood loss. Results Validation exercise: the mean percentage error of gravimetrically measured blood volume was 4.0 ± 2.7% compared to visually estimated blood volume with a mean percentage error of 34.7 ± 32.1%. Clinical observation study: 356 out of 6187 deliveries were identified as having major postpartum haemorrhage. The correlation coefficient between measured blood loss and corrected fall in haemoglobin for all patients was 0.77; correlation was stronger (0.80) for postpartum haemorrhage >1500 mL, and similar during routine and out-of-hours working. Conclusion The accuracy of the gravimetric method was confirmed in simulated postpartum haemorrhage. The clinical study shows that gravimetric measurement of blood loss is correlated with the fall in haemoglobin in postpartum haemorrhage where blood loss exceeds 1500 mL. The method is simple to perform, requires only basic equipment, and can be taught and used by all maternity services during major postpartum haemorrhag