Establishment and evaluation of intraoperative blood transfusion prediction model based on random forest algorithm / 中国输血杂志

【Objective】 To predict the risk factors of intraoperative blood transfusion by establishing a random forest algorithm prediction model, and to evaluate its prediction performance in clinical. 【Methods】 A total of 48 176 patients who underwent surgery from January 2014 to December 2017 in the First Medical Center of the Chinese People′s Liberation Army General Hospital were collected and divided into a blood transfusion group(n=5 035) and a non-transfusion group(n=43 141) according to whether blood was transfused or not during the operation, and the age, gender, weight, blood routine, coagulation test indicators, surgical grade, number of operations and anesthesia methods, and preoperative blood transfusion history between the two groups were compared and analyzed. All cases were randomly divided into training set(n=33 723) and the test set(n=14 453), using the sklearn function package in the computer programming language(Python V 3.9.0) to introduce the random forest algorithm, with 2 groups of different factors incorporated into the random forest algorithm to build the model, and the model was evaluated using the operating curve(ROC). 【Results】 1) There were statistically significant differences between the blood transfusion group and the non-transfusion group in terms of gender, age, blood routine, coagulation function, surgical grade, and preoperative blood transfusion history(P0.05); 3) In the established intraoperative blood model, the blood routine, coagulation function and general anesthesia had a great influence, with the cumulative importance > " 0.90" ; 4) The ROC analysis showed that the area under the ROC curve of the random forest model was 0.91 and 0.82 in the training set and the test set, which demonstrated a good predictive ability. 【Conclusion】 The intraoperative blood, using prediction model based on random forest method, can predict intraoperative blood use and blood transfusion risk factors.

Blood typing in positive DEA 1 dogs: comparative analysis between immunochromatography, hemagglutination and flow cytometry / Tipificação sanguínea em cães AEC 1 positivo: análise comparativa entre a imunocromatografia, hemoaglutinação e citometria de fluxo

Blood typing techniques have been improved to ensure greater safety for transfusion procedures. Typification for the DEA 1 antigen through flow cytometry should offer more reliability to routine immunohematology in donor and recipient dogs. Currently, the DEA 1 group is starting to be an autosomal dominant allelic system with the DEA 1 negative type and its variations of positivity. The present study investigated the DEA 1 antigen using the techniques of immunochromatography, hemagglutination and flow cytometry. Among the positive animals for the DEA 1 group, typified by flow cytometry, medium intensities of fluorescence were found, which are indicative of weak, moderate and strong antigenicity. This enabled the division of the DEA 1 group into weak positive, moderate positive and strong positive. The blood typing techniques for the DEA 1 group by flow cytometry, agglutination and immunochromatography had positive (Spearman r=0.70) and statistically significant (p>0.0001) correlations.(AU)

As técnicas de tipificação sanguínea vêm sendo aperfeiçoadas para garantir maior segurança aos procedimentos transfusionais. A tipificação para o antígeno AEC 1 com o emprego da citometria de fluxo poderá oferecer mais confiabilidade à rotina da imunohematologia em cães doadores e receptores. Na atualidade, o grupo AEC 1 passou a ser denominado como um sistema alélico autossômico dominante com o tipo AEC 1 negativo e suas variações de positividade. O presente trabalho comparou os resultados de três técnicas utilizadas para a pesquisa do antígeno AEC 1: cromatografia; hemoaglutinação e citometria de fluxo. Dentro dos indivíduos positivos para o grupo AEC 1, tipificados pela citometria de fluxo, foram encontradas intensidades médias de fluorescência indicadoras de antigenicidade fraca, moderada e forte, podendo-se dividir o grupo AEC 1 em positivo fraco, positivo moderado e positivo forte. As técnicas de tipificação sanguínea para o grupo AEC 1 por cromatografia, hemoaglutinação e citometria de fluxo apresentaram correlação positiva (Spearman r=0,70) e estatisticamente significativa (p<0,0001).(AU)

Frequency of dog erythrocyte antigen 1 blood group and risk of incompatible transfusion in dogs of different breeds and mongrels from the city of Salvador - BA, Brazil / Frequência do antígeno eritrocitário canino 1 e risco de transfusão incompatível em cães de diferentes raças e mestiços da cidade de Salvador-BA, Brasil

The dog erythrocyte antigen 1 (DEA 1) is the most immunogenic blood group in dogs, and blood transfusions may trigger some undesirable effects in veterinary patients, which are directly associated with incompatible transfusions. The present study aimed to investigate the frequency of positive DEA 1 blood group in blood donor dogs from a blood bank in Salvador, Bahia, Brazil, and also to calculate the risk of managing incompatible blood in both first and second transfusion. A number of 203 dogs of different breeds, aged between 1 and 8 years, weighing 28 kg, with no degree of kinship and of both sexes in Salvador - BA, Brazil were evaluated to investigate the blood type DEA 1 frequency, by means of chromatography and flow cytometry tests for blood typing. The risk of incompatible blood transfusion in either a first or a second transfusion was also calculated. The frequency of the DEA 1 group ranged from 0% to 100% in various breeds, but with a mean positivity of 62.07% (126/203). And the lowest risk of an DEA 1 negative animal receiving DEA 1 positive blood within the group of animals evaluated was 0.92% at a first transfusion; and the risk of the same animal receiving incompatible blood for the DEA group 1 in the second transfusion was 0.008%. The highest risk of an DEA 1 negative animal receiving DEA 1 positive blood from these animals was 69.12%; and the risk of receiving incompatible blood for DEA 1 was 47.77%. In conclusion, the frequency of the DEA 1 group varied between the studied breeds and the risk of incompatible blood transfusions varies according to donor and recipiente breeds, but this can be overridden if blood typing tests are performed along with the cross-reaction test for compatibility.

O antígeno eritrocitário canino 1 (AEC 1) é o grupo sanguíneo mais imunogênico em cães, podendo as transfusões sanguíneas desencadearem alguns efeitos indesejáveis nos pacientes veterinários. Estes estão diretamente associados à transfusões incompatíveis. O presente trabalho teve como objetivo estudar a frequência do grupo sanguíneo AEC 1 em cães doadores de sangue de um banco de sangue de Salvador-BA, Brasil, e calcular o risco de administrar sangue incompatível tanto em uma primeira quanto em uma segunda transfusão. Foram avaliados 203 cães de diversas raças, de ambos os sexos, com idade entre 1 e 8 anos, peso a partir de 28 kg, sem nenhum grau de parentesco originários de Salvador ­ BA, Brasil, para pesquisa da frequência do tipo sanguíneo AEC 1, por meio de testes de imunocromatografia e citometria de fluxo para tipagem sanguínea. E calculado o risco de transfusão sanguínea incompatível tanto em uma primeira como em uma segunda transfusão. A frequência do grupo AEC 1 variou entre as raças estudadas de 0% a 100%, porém com uma positividade média de 62,07% (126/203). O menor risco de um animal AEC 1 negativo receber sangue AEC 1 positivo, dentro do grupo dos animais avaliados foi de 0,92% em uma primeira transfusão e o risco do mesmo animal receber sangue incompatível para o gruo AEC 1 na segunda transfusão foi de 0,008%. Quanto ao maior risco de um animal AEC 1 negativo receber sangue AEC 1 positivo destes animais foi de 69,12% e o risco do mesmo receber sangue incompatível para o AEC 1 foi de 47,77%. A frequência do grupo AEC 1 variou entre as raças estudadas e o risco de transfusões incompatíveis variou de acordo com as raças doadoras e receptoras, mas esse risco pode ser anulado se sempre forem realizados os testes para tipagem sanguínea junto com a prova de reação cruzada para compatibilidade.

Risk of Zika virus transmission by blood donations in Brazil

ABSTRACT Background: Zika, a disease caused by Zika virus infections, has recently emerged and caused outbreaks in many parts of the world. The clinical manifestations of Zika are usually mild, mostly presenting as an exanthematic febrile disease, but on some occasions, it might be associated with microcephaly after intrauterine infection, and Guillain-Barré Syndrome. Zika virus is primarily transmitted by mosquito bites, but other means of transmission have been described, and potential risk for blood transmission has been reported in French Polynesia and Brazil. Methods: To investigate the risk of Zika virus infection after a blood transfusion in an area of Brazil where a possible transmission by a platelet concentrate has been described. Using a mini-pool format, 1857 blood donations were evaluated by real-time reverse transcriptase polymerase chain reaction designed to detect Zika virus RNA. Results: After testing samples individually from positive mini-pools, the prevalence of Zika virus RNA was only 0.16%, a result probably associated to the low circulation of this virus in the study area. In addition, it was evident that the implementation of post-surveillance programs is important to detect Zika virus infections in blood donors, as the post-donation surveillance program detected two blood donors with the disease in this study. Conclusion: This study shows that the risk for Zika virus transmission by blood transfusion is real, even in regions with a low circulation of the disease, but the combination of the detection of Zika virus RNA by polymerase chain reaction and post-donation surveillance might reduce the risk of transmission by blood transfusions.

Estudo da frequência dos antígenos eritrocitários caninos 1, 1.1 e 7 e risco de transfusão incompatível em cães de diferentes raças e mestiços da região metropolitana da cidade de São Paulo-SP, Brasil / Study of the frequency on the dog erythrocyte antigen 1, 1.1 and 7 and incompatible transfusion risk in different dog breeds and mongrel dogs of the metropolitan region of São Paulo-SP, Brazil

O presente trabalho estudou a frequência dos grupos sanguíneos identificados como antígenos eritrocitários caninos (AEC) 1, 1.1 e 7 em cães da região metropolitana da cidade de São Paulo-SP, Brasil, e calculou o risco de administração de sangue incompatível tanto em uma primeira quanto em uma segunda transfusão. Para tanto, 300 cães não aparentados foram divididos igualmente em seis grupos de acordo com as raças: Pastor Alemão (PA); Rottweiler (R); Poodle (P); Cocker Spaniel Inglês (CS); raças definidas diversas (RDD) e mestiços (M). Foi avaliada a relação entre a frequência dos AEC e os grupos raciais. A frequência geral de AEC 1 na população foi de 71 por cento (AEC 1.1 – 53,35 por cento) e houve variações de acordo com as raças: PA- 32 por cento (AEC 1.1 – 20 por cento), R- 98 por cento (1.1 – 80 por cento), P- 76 por cento (1.1 – 54 por cento), CS- 84 por cento (1.1 – 50 por cento), RDD- 62 por cento (1.1 – 56 por cento) e M- 74 por cento (1.1 – 60 por cento). A frequência geral de AEC 7 foi de 39,33 por centoe não houve diferenças significativas entre as raças. O risco de um cão negativo para o AEC 1 receber sangue positivo foi de 0,6 a 66,6 por cento em uma primeira transfusão e de 0,21 a 65,3 por cento do mesmo cão receber sangue incompatível em uma segunda transfusão. O risco quanto ao AEC 7 foi de 23,86 por cento na primeira transfusão e 9,4 por cento numa segunda transfusão. Este trabalho concluiu que houve variação na frequência de AEC1 e AEC 1.1, mas não quanto ao AEC 7 entre raças. Esta variação na porcentagem de animais positivos quanto ao AEC 1 se refletiu na grande variação no risco de uso de sangue incompatível. Portanto, conhecer a frequência dos AEC na população tem impacto direto no manejo entre cães doadores e receptores, mas a utilização conjunta de teste de tipagem sanguínea e reação cruzada reduz a possibilidade de transfusão de sangue incompatível.

It was investigated the frequency of blood groups identified as Dog Erythrocyte Antigens (DEA) 1, 1.1 and 7 dogs in the metropolitan region of São Paulo-SP, Brazil, and calculated the risk of administering incompatible blood in both first and second transfusion. For both, 300 unrelated dogs were equally divided into six groups according to the breeds: German Shepherd (GS), Rottweiler (R) Poodle (P), Cocker Spaniel (CS); defined several races (DSR), mongrel dogs (M). It was evaluated the relationship between the frequency of AEC and racial groups. The overall frequency of DEA 1 in population was 71 percent (DEA 1.1 – 53.35 percent) and there were variations according to the breeds: GS- 32 percent (DEA 1.1 – 20 percent), R –98 percent (1.1 – 80 percent) P – 76 percent (1.1 – 54 percent), CS-84 percent (1.1 – 50 percent), DSR- 62 percent (1.1 – 56 percent) and M – 74 percent(1.1 – 60 percent). The overall frequency of BCE 7 was 39.33 percent, and there were no significant differences between the breeds. The risk of a dog negative DEA receiving 1 positive blood was 0.6 to 66.6 percent in the first transfusion and 0.21 to 65.3 percent from the same animal dog receiving incompatible blood transfusion in a second. The risk of the DEA 7 was 23.86 percent in the first transfusion and 9.4 percent in a second transfusion. This study concluded that there was variation in the frequency of DEA 1 and 1.1, but not on the DEA 7 between races. This variation in the percentage of positive animals to DEA 1 was reflected in the large variation in the risk of use of incompatible blood. Therefore, knowing the frequency of the DEA in the population has a direct impact on handling dogs between donors and recipients, but the joint use of testing blood typing and cross-reactivity reduces the possibility of incompatible blood transfusion.