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Investigating Tissue factor gene regulation using the Chromosome Conformation Capture (3C) techniquePalisetty, Hari vanaja January 2011 (has links)
No description available.
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Experimental Studies on Diagnostic and Therapeutic Aspects of Intraosseous AccessStrandberg, Gunnar January 2017 (has links)
Reliable access to the circulation is paramount in most medical and surgical emergencies. When venous access cannot be expediently established, intraosseous (IO) access is indicated. This method has a high success rate even in relatively inexperienced hands and there is considerable clinical experience of IO administration of drugs and fluids. There is however limited evidence on the use of IO samples for laboratory analysis. Also, uptake of drugs during shock has not been extensively studied. Further, there have been concerns that analysis of IO samples may damage laboratory equipment. We have studied, in a porcine model, the use of IO samples for point of care analysis of blood gases, acid base parameters and blood chemistries in stable circulation, in experimental septic shock, and in hypovolemia after major hemorrhage, comparing IO samples with arterial and venous samples, and comparing IO samples from different sites. We have also studied coagulation assays on IO samples in stable circulation and after major hemorrhage. Furthermore, we have compared IO and intravenous administration of antibiotics in experimental sepsis. Average differences between IO and arterial/venous samples varied between the studied analytes. During stable circulation, average IO levels of blood gases, acid-base parameters, hemoglobin/hematocrit and several blood chemistries approximated venous levels relatively well. Differences in acid-base and blood gas parameters, and lactate, were more pronounced in hypovolemia, as well as in sepsis. The dispersion of the differences was often relatively large, indicating limited precision. Average differences between two intraosseous sites were small. Intraosseous samples were clinically hypercoagulable with a strong tendency to clot in vitro, and thromboelastography demonstrated shortened reaction times compared with venous samples. Major bleeding and hemodilution moderately affected the studied coagulation parameters. In endotoxemic animals with circulatory instability, concentrations of cefotaxime and gentamicin in samples from the pulmonary artery were comparable at 5 minutes after intraosseous and intravenous administration, and during a 3 hour observation period. In summary, agreement between analytes in intraosseous and conventional blood samples was variable and often unpredictable, especially during circulatory compromise. Intraosseous samples clinically appeared hypercoagulable, and thromboelastography confirmed this. High and comparable concentrations of cefotaxime and gentamicin were found after intraosseous and intravenous administration of equivalent doses, suggesting that uptake is acceptable during septic instability.
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Novas estratégias de purificação dos fatores de coagulação Fator VIII e Proteína C a partir de plasma humano empregando cromatografia líquida. / New strategies of purification of coagulation Factor VIII and Protein C from human plasma using liquid chromatography.Claudia Iwashita 19 March 2012 (has links)
Neste trabalho estudou-se a purificação de fator VIII de coagulação (FVIII) e da Proteína C (PC) por cromatografia. Em coluna ANX Sepharose FF como primeira etapa de purificação do plasma permite a eluição do FVIII e da PC com bom fator de purificação, mas não a separação destas. Propomos a separação de FVIII e PC empregando cromatografia de afinidade a metal (IMAC) empregando Cu2+, Ni2+, Zn2+, Co2+ e Fe3+ e dessorção empregando imidazol, cloreto de amônio e variação de pH. Em colunas de Fe3+ e Ni2+ as proteínas praticamente não se ligaram à resina. Em IMAC-Co2+, a PC não é adsorvida pela resina enquanto o FVIII pode ser eluído com imidazol 100 mM. Em IMAC-Cu2+ a PC eluiu com imidazol 10mM e o FVIII com 200mM. Não foi possível eluir as proteínas nem com NH4Cl 1M nem quando o pH foi abaixado até 4,0. Em IMAC-Zn2+ a PC não é adsorvida e o FVIII eluiu com imidazol 200mM ou NH4Cl 1M. Diminuindo-se o pH, a recuperação da atividade do FVIII foi baixa. Concluímos que IMAC-Co2+ apresentou os melhores rendimentos e melhores fatores de purificação para as 2 protéinas. / In this work purification methods for the coagulation factor VIII (FVIII) and Protein C (PC) by chromatography was studied. The use of ANX Sepharose FF column as the first purification step allows the elution of FVIII and PC with good purification factors, but not its separation. We propose the separation of FVIII and PC using immobilized metal ion affinity chromatography (IMAC) using Cu2+, Ni2+, Zn2+, Co2+ and Fe3+ and desorption employing imidazole, ammonium chloride and pH variation. In the columns containing Fe3+ and Ni2+ metal ions, proteins did not adsorb to the resin. In IMAC-Co2+, PC was not adsorbed to the resin, while FVIII could be eluted with 100 mM imidazole. In IMAC-Cu2+ PC could be eluted with 10 mM imidazole and FVIII with 200 mM. It was not possible to elute the proteins from IMAC-Cu2+ column with either 1M NH4Cl or when pH was descreased to 4,0. In IMAC-Zn2+, PC was not adsorbed and FVIII could be eluted with 200 mM imidazole or 1 M NH4Cl. We conclude that IMAC-Co2+ presented the best yield and purification factors for the 2 proteins.
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Estudo de fatores protrombóticos e proinflamatórios na cardiomiopatia chagásica / Evaluation of prothrombotic and proinflammatory factors in Chagas cardiomyopathyLeila Maria Magalhães Pessoa de Melo 17 July 2009 (has links)
Fundamento: A ativação da cascata inflamatória está presente na insuficiência cardíaca(IC). Existe relação entre esta ativação e estado protrombótico nesta síndrome. Dentre as etiologias de IC, a cardiomiopatia chagásica (CMC) parece ter maior ativação inflamatória e prognóstico mais reservado, possivelmente por especial risco para fenômenos tromboembólicos. A relação entre atividade inflamatória e protrombótica na cardiomiopatia chagásica e em outras etiologias é obscura. Objetivo: Estudar o perfil de marcadores protrombóticos e proinflamatórios em pacientes com insuficiência cardíaca chagásica comparando-os com os de etiologia não-chagásica. Métodos: Corte transversal. Critérios de inclusão: fração de ejeção do VE (FEVE) < 45% e tempo de início de sintomas > 1 mês. Os pacientes foram divididos em dois grupos: grupo 1(G1) sorologias positivas para Chagas e grupo 2(G2) sorologia negativa para Chagas. Dosou-se como fatores proinflamatórios: fator de necrose tumoral-alfa (TNF-), interleucina-6 (IL-6) e proteína C reativa (PCR) ultrassensível; fatores protrombóticos: dímero D, P-selectina solúvel, antígeno do fator de von Willebrand, fibrinogênio, complexo trombina-anti-trombina(TAT), fator tecidual(FT) e tromboelastograma(TEG). A amostra foi calculada para poder de 90%, assumindo-se diferença de 1/3 de desvio-padrão entre os grupos; p significativo se < 0,05. Análise estatística: teste exato de Fischer para comparação de proporções; teste t de student não-pareado para variáveis contínuas de distribuição normal e teste de Mann-Whitney para variáveis contínuas de distribuição assimétrica. Realizada análise de co-variância para ajuste de potenciais influências de co-variáveis. Resultados: Entre 16 de janeiro de 2008 e 08 de abril de 2009, 287 pacientes com IC crônica foram consecutivamente selecionados em nível ambulatorial ou de internação, sendo 138 no G1 e 149 no G2. O G1 apresentava maior porcentual de pacientes internados, de CF III/IV, PA sistólica mais baixa, maior freqüência de RHJ, ascite, menor fração de ejeção e níveis mais altos de BNP. Por outro lado, a prevalência de HAS, DM e DLP foi superior no G2. Dos marcadores proinflamatórios, o TNF- foi maior no G1, independentemente de outros fatores de gravidade(p<0,0001). A IL-6, apesar de maior no G1, sofreu maior influência de outras variáveis de gravidade do que da etiologia chagásica. Os níveis de PCR ultrassensível estavam elevados em ambos os grupos embora sem diferença entre eles. Dentre os fatores protrombóticos o dímero-D(p<0,0001), o fator de von Willebrand(p<0,0001) e a P-selectina(p=0,0262) foram mais altos no G1 que no G2. Os níveis de FT e TAT foram semelhantes. O fibrinogênio foi mais alto no G2 que no G1(p=0,0424), assim como os parâmetros do TEG - MA(p=0,0044), G(p=0,0022) e TG(p=0,001), embora todos estivessem dentro dos limites de referência na maioria dos pacientes em ambos os grupos. Na análise de co-variância apenas o dímero-D e a P-selectina mantiveram-se diferentes entre os grupos, sendo que os níveis de P-selectina estavam normais na maioria dos pacientes de ambos os grupos. Conclusões: A atividade proinflamatória esteve aumentada nos pacientes com IC chagásica e não-chagásica. A inflamação medida pelo TNF- foi independentemente maior entre chagásicos.Observou-se maior estado protrombótico entre chagásicos medido pelo dímero-D, independentemente de outros fatores de gravidade. / Background: Inflammatory cascade activation is present in heart failure (HF). This activation is closely related to a prothrombotic state in this syndrome. Among HF etiologies, Chagas cardiomyopathy (CCM) seems to have greater inflammatory activation and worse prognosis, possibly because of special risk for thromboembolic phenomena. The relation of inflammatory and prothrombotic activity between CCM and other HF etiologies remains unclear. Objective: To assess the profile of prothrombotic and proinflammatory markers in patients with chagasic in comparison to non-chagasic systolic heart failure. Methods: Cross sectional study. Inclusion criteria: LV ejection fraction (LVEF) < 45% and time of symptoms onset > 1 month. Patients were divided into two groups: group 1 (G1) positive Chagas serology and group 2 (G2) negative serology. Proinflammatory factors determined: tumor necrosis factor (TNF-), interleukin-6(IL-6) and ultrasensitive C-reactive protein (CRP); prothrombotic factors: D-dimer, soluble P-selectin, von Willebrand factor(vWF), fibrinogen, thrombin-anti-thrombin complex(TAT), tissue factor(TF) and thromboelastography(TEG). Sample was calculated for an 90% power, assuming a difference of 1 / 3 of the standard deviation; p significant if < 0.05. Statistical analysis: Fischer exact test for proportions, non-paired Students t test for parametric continuous variables and Mann-Whitney test for non-parametric continuous variables. Covariance analysis was performed to adjust for possible covariables influence on results. Results: From january 16th to april 8th 2009, 287 chronic HF patients were consecutively included, 138 in G1 and 149 in G2. G1 showed larger proportion of inpatients, higher III/IV functional class, lower systolic blood pressure, higher frequency of hepatojugular reflux, ascites, lower left ventricle ejection fraction and higher levels of B-type natriuretic peptide (BNP). On the other hand, G2 had higher proportion of hypertension, diabetes and hypercholesterolemia. Among proinflammatory markers, TNF- levels were higher in G1, independently of other prognosis variables (p<0,0001). Although IL-6 levels were higher in G1, there was greater influence of other prognosis variables than chagasic etiology itself. CRP levels were above reference values but there was no difference between G1 and G2. Among prothrombotic markers, D-dimer(p<0,0001), vWF(p<0,0001) and soluble P-selectin(p=0,0262) levels were higher in G1 than in G2. TF and TAT levels were similar in both groups. Fibrinogen levels were higher in G2 than in G1 (p = 0.0424), as well as TEG parameters MA(p=0,0044), G(p=0,0022) and TG(p=0,001), even though all of them were in normal reference range in most patients in both groups. D-dimer and soluble P-selectin kept different among groups in covariance analysis. However, soluble P-selectin levels were in normal reference range in both groups. Conclusions: Proinflammatory activity was increased in both groups. Inflammation measured by TNF- was independently greater among CCM patients. Greater prothrombotic state measured by D-dimer was observed in CCM patients independently of other prognosis variables.
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Point-of-care Blood Coagulation Monitoring Using Low-cost Paper-based No-reaction Lateral Flow Assay DeviceLi, Hua 29 October 2018 (has links)
No description available.
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Qualitative Blood Coagulation Test Using Paper-Based Microfluidic Lateral Flow DeviceLi, Hua 13 October 2014 (has links)
No description available.
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Platelet flow cytometry and coagulation tests as markers of immune activation in chronic HIV infectionNkambule, Bongani Brian 03 1900 (has links)
Thesis (MScMedSc)--Stellenbosch University, 2012. / Bibliography / ENGLISH ABSTRACT: Background: In the era of antiretroviral therapy (ART), the risk of acquired immune deficiency
syndrome (AIDS) related deaths has decreased and people living with Human
Immunodeficiency Virus (HIV) now have prolonged life spans. However, an increasing trend of
non-AIDS associated deaths has been reported despite adequate control of viral loads. HIV
infection is established as a chronic inflammatory condition which is associated with an
increased risk for thrombosis. Thus HIV infected patients are at a higher risk of developing
cardiovascular disease (CVD) and other inflammatory-associated complications.
Inflammation is linked with thrombosis and promotes the formation of thrombin, which plays an
important role in platelet activation. Furthermore, activated platelets have been shown to play a
key role during infection and the inflammatory process, particularly by mediating interactions
between cells of innate immunity. Soluble markers of platelet activation have been shown to be
increased in HIV-infection. However, these have not been well documented by flow cytometry.
P-selectin CD62P is stored in the alpha granules of platelets and is expressed on the surface
only upon platelet activation. This facilitates interaction with other blood cells and the
endothelium. Activated platelets may play a role in HIV-induced atherosclerosis through the
expression and release of mediators that induce endothelial activation and support the adhesion
of leukocytes to the inflamed vessel wall. Fibrinogen is a precursor of the blood coagulatory
protein fibrin and the degradation of fibrin to D-dimer is a measure of the formation and the
subsequent dissolution of blood clots. In HIV infected patients, chronic inflammation induces the
up-regulated expression of tissue factor (TF) on monocytes which triggers the activation of the
clotting cascade and increases the level of D-dimers.
Methods: This pilot study consisted of ART naïve patients and all platelet flow analyses were
carried out on whole blood. In this study, a total of 57 adult South Africans were recruited from a
clinic in the Western Cape. These included 32 HIV positive patients and 25 HIV negative
individuals. The levels of platelet activation and platelet function were investigated using a novel
platelet cytometry assay. The method was optimized to ensure minimal platelet activation: no
centrifugation or red blood cell (RBC) lysis steps were performed. The platelet-specific markers
CD41a and CD42b were used to ensure gating on platelets only. CD62P expression was used
to evaluate platelet activation and these levels were correlated with Fibrinogen, hsCRP, Ddimer,
CD4 counts and viral load. Furthermore, platelet function was evaluated by investigating
the response of platelets to endogenous agonists which included adenosine diphosphate(ADP)
and arachidonic acid (AA) at varying concentrations. Results:This study demonstrated higher baseline levels of CD62P expression in treatment
naïve HIV positive patients as compared to uninfected controls (mean %CD62P 71.74 ± 2.18 vs
control 54.52 ± 2.42; p=<0.0001). In addition it was shown that %CD62P expression correlated
directly with platelet counts (r=0.374, p=0.042). Platelet counts showed an inverse correlation
with viral loads (give values) Fibrinogen levels correlated with the absolute WCC (r=0.659,
p=0.0021); absolute neutrophil count (r=0.619, p=0.0105); absolute monocyte count (0.562,
p=0.0235) and hsCRP (r=0.688 p=0.0011). In addition, fibrinogen showed a strong negative
correlation with CD4 counts (r=-0.594, p=0.0014) and therefore, may be a valuable marker of
both disease progression and risk of thrombosis in treatment naïve HIV positive patients.
HsCRP levels correlated with the absolute neutrophil counts (r=0.392, p=0.0005). The HIV
Group showed an overall hyper-response to ADP at a concentration 0.025 μM as compared to
uninfected controls (62.34 ± 9.7 vs control 36.90 ± 5.7, p=0.0433). Conclusions: In this study we describe a novel Flow Cytometry technique that may be used to
evaluate the levels of platelet activation and platelet function in HIV infected patients. In addition
we report a cost-effective panel in the form of fibrinogen, WCC and platelets that may be
valuable in predicting the progression of HIV infection to AIDS or other inflammatory- associated
complications in treatment naïve HIV infected patients. Platelet counts showed an inverse
correlation with viral loads and a direct correlation with the level of activated platelets. These
findings taken together suggest the potential prognostic value of platelet activation and platelet
counts in the context of asymptomatic HIV infected patients. Our findings suggest WCC and
Fibrinogen may be used to evaluate the inflammatory profile of individual HIV infected patients.
This may have a direct impact on HIV patient management prior to initiation of antiretroviral
therapy and valuable in monitoring responses to treatment. Further, we present a novel flow
cytometry based platelet functional assay and suggest the use of ADP at a concentration of
0.025 μM to evaluate platelet function optimally in HIV infected patients. The utilization of the
novel Flow Cytometry technique as described in this study would add significant value in the
assessment of thrombotic risk and disease progression in HIV infected patients and may
additionally prove to be of value in other chronic inflammatory conditions. / AFRIKAANSE OPSOMMING: Voorkennis: In die era van antiretrovirale terapie (ART), het die risiko van vigs-verwante
sterftes verminder en mense wat nou met volle naam (MIV) leef, het ‘n verlengde lewensduur.
Nogtans, word 'n toenemende neiging van nie-vigs geassosieer sterftes berig wat hoofsaaklik
toegeskryf word aan trombotiese toestande. MIV-infeksie word as 'n chroniese inflammatoriese
toestand beskou met ʼn verhoogde trombose risiko geassosieer word. Dus, MIV-besmette
pasiënte het 'n hoër risiko om kardiovaskulêre siekte (CVD) te ontwikkel ongeag of hulle ARV
naïef is of op behandeling is nie.
Inflammasie word geassosieer met trombose en bevorder die vorming van trombien, wat 'n
belangrike rol in plaatjie aktivering speel. Verder, word daar bewys dat geaktiveerde
bloedplaatjies 'n belangrike rol speel tydens infeksie en die inflammatoriese proses.Hulle
bemiddel interaksies tussen die selle van ingebore immuniteit. Daar word bewys dat oplosbare
merkers van plaatjie aktivering verhoog is in MIV-infeksie, maar die bewyse is nie so goed
gedokumenteer deur vloeisitometrie nie. P-selectin (CD62P) word gestoor in die alfa korrels van
plaatjies en word uitgedruk op die oppervlak slegs wanneer plaatjies geaktivering word;
daardeur fasilitering dit die interaksie met ander bloedselle en die endoteel. Geaktiveerde
plaatjies kan ook 'n rol in MIV-geïnduseerde aterosklerose speel deur middel van die uitdrukking
en vrylating van bemiddelaars wat endoteel aktivering induseer asook die adhesie van
leukosiete aan die ontsteekte vat wand ondersteun.. Fibrinogeen, 'n voorloper van die bloed
koagulatories proteïen fibrin en die degradasie van fibrin na D-dimeer is' n maatstaf van die
vorming en die daaropvolgende ontbinding van bloedklonte. Kroniese inflammasie in MIVbesmette
pasiënte, induseer die op-gereguleerde uitdrukking van weefsel faktor (TF) op
monosiete wat die aktivering van die stolling kaskade inisieer en die D-dimere vlakke verhoog.
Metodes: Hierdie loodsstudie bestaan uit ART naïewe pasiënte en al die plaatjie vloei ontleding
was op vol bloed uitgevoer. In hierdie studie, 'n totaal van 57 volwasse Suid-Afrikaners was van'
n kliniek in die Wes-Kaap gewerf. Dit sluit 32 MIV-positiewe pasiënte en 25 MIV negatiewe individue in. Die vlakke van plaatjie aktivering en plaatjie funksie was ge ondersoek deur middel
van 'n nuwe plaatjie sitometrie toets. Die metode was geoptimaliseer om minimale plaatjie
aktivering te verseker: dus geen sentrifugering of volle naam (RBS) liseer stappe was gebruik
nie. Die plaatjie-spesifieke merkers, CD41a en CD42b was gebruik om te verseker dat slegs
bloedplaatjes gekies word. Die uitdrukking van CD62P was gebruik vir die evaluering van
plaatjie aktivering en hierdie vlakke was gekorreleer met fibrinogeen, hsCRP, D-dimeer, CD4-
tellings en virale lading. Verder, was plaatjie funksie geëvalueer deur die reaksie van plaatjies
aan endogene agoniste wat ADP en AA by wisselende konsentrasies insluit te ondersoek.
Results: Hierdie studie het getoon hoër basislyn vlakke van CD62P uitdrukking in behandeling
naïewe MIV-positiewe pasiënte in vergelyking met onbesmette beheermaatreëls (beteken%
CD62P 71,74 ± 2,18 vs beheer 54,52 ± 2,42, p <0.0001). Daar is ook getoon dat% CD62P
uitdrukking direk gekorreleer met plaatjie tellings (r = 0,374, p = 0,042). Plaatjie tellings het 'n
omgekeerde korrelasie met virale ladings (gee waardes) fibrinogeen vlakke korreleer met die
absolute WCC (r = 0,659, p = 0,0021), absolute neutrofiel telling (r = 0,619, p = 0,0105);
absolute monosiet telling (0,562, p = 0,0235) en hsCRP (r = 0,688 p = 0,0011). Daarbenewens,
fibrinogeen het 'n sterk negatiewe korrelasie met 'n CD4-tellings (r = -0,594, p = 0,0014) en
daarom kan 'n waardevolle merker van beide die siekte en die risiko van trombose in
behandeling naïewe MIV-positiewe pasiënte. HsCRP vlakke gekorreleer met die absolute
neutrofiel tellings (r = 0,392, p = 0,0005). Die MIV-groep het 'n algehele hiper-reaksie op die
ADP by 'n konsentrasie 0,025 μM in vergelyking met onbesmette beheermaatreëls (62,34 ± 9,7
vs beheer 36,90 ± 5.7, p = 0,0433).
Gevolgtrekkings: In hierdie studie beskryf ons 'n roman vloeisitometrie tegniek wat gebruik kan
word om die vlakke van Plaatjie aktivering en plaatjie funksie in die MIV-besmette pasiënte te
evalueer. Verder het ons 'n verslag van 'n koste-effektiewe paneel in die vorm van fibrinogeen,
WCC en plaatjies wat waardevol kan wees in die voorspelling van die vordering van MIVinfeksie
tot VIGS of ander inflammatoriese-verwante komplikasies in die behandeling naïewe
MIV-besmette pasiënte. Plaatjie tellings het 'n omgekeerde korrelasie met die virale laste en 'n
direkte verband met die vlak van geaktiveerde bloedplaatjies. Hierdie bevindinge saam, dui op
die moontlike prognostiese waarde van Plaatjie aktivering en die plaatjie tel in die konteks van
die asimptomatiese MIV-geïnfekteerde pasiënte. Ons bevindinge dui daarop WCC en fibrinogeen kan gebruik word om die inflammatoriese profiel van individuele MIV-geïnfekteerde
pasiënte te evalueer. Dit kan 'n direkte impak op MIV pasiënt vooraf aan die inisiasie van
antiretrovirale terapie en waardevolle in die monitering van die reaksie op behandeling. Verder
bied ons 'n roman vloeisitometrie gebaseer plaatjie funksionele toets en dui op die gebruik van
die ADP teen 'n konsentrasie van 0,025 μM plaatjie funksie optimaal te evalueer in MIVgeïnfekteerde
pasiënte. Die benutting van die roman vloeisitometrie tegniek soos beskryf in
hierdie studie sal 'n beduidende waarde toevoeg in die beoordeling van die die trombotiese
risiko en die siekte in MIV-geïnfekteerde pasiënte en kan addisioneel bewys van waarde te
wees in 'n ander chroniese inflammatoriese toestande. / National Reserach Foundation
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Papel da tromboelastometria em pacientes com dengue e trombocitopenia / Thromboelastometry role in patients with dengue and thrombocytopeniaPiza, Felipe Maia de Toledo 19 July 2016 (has links)
INTRODUÇÃO: Dengue é uma doença viral prevalente e potencialmente fatal associada à alteração da permeabilidade capilar e coagulopatia. Entretanto, não há estudos concernentes aos achados tromboelastométricos nesta doença. Realizamos o presente estudo para analisar pacientes com dengue e plaquetopenia por meio de um exame rápido, efetivo e a beira leito comparando com os exames convencionais de coagulação. MÉTODOS: Trata-se de um estudo observacional e transversal conduzido entre os dias 6 de abril a 5 de maio de 2015, em São Paulo, Brasil, durante epidemia de dengue. Foi realizado tromboelastometria ROTEM® em 53 pacientes com dengue e trombocitopenia em associação com exames convencionais de coagulação: tempo de protrombina (TP), international normalized ratio (INR), tempo de tromboplastina parcial ativado (TTPa), tempo de trombina (TT), contagem de plaquetas, fibrinogênio e d-dímero. Um grupo controle de pacientes foi estabelecido para comparação do status tromboelastométrico. RESULTADOS: Um total de 38 pacientes de 53 (71,7%) apresentaram anormalidades no INTEM e 29/53 (57,4%) no EXTEM. Em contrapartida, alterações no FIBTEM foram encontradas apenas em 3/53 (5,7%). Houve significância estatística em pacientes correlacionando alterações tromboelastométricas no EXTEM e INTEM e contagem de plaquetas (p=0,052) e (p=0,005), respectivamente; assim como os valores de fibrinogênio (p=0,006) e (p=0,021), respectivamente. O grupo controle (GC) apresentou status tromboelastométrico normal em 10/10 (100%) na análise do INTEM, EXTEM, FIBTEM. Avaliação do EXTEM demonstrou significância estatística entre o GC e o grupo Dengue: CT (p=0,044); CFT (p<0,001); MCF (p < 0,001) e Alpha (p < 0,001). Foram observados níveis normais de fibrinogênio (mediana: 290) e altos níveis de d-dímero (mediana: 1330) com IQR (800-1840). Todos os pacientes (53/53) apresentavam trombocitopenia abaixo de 100 x 109/L (mediana 77 x 109/L) IQR (63-88). Exames convencionais de coagulação revelaram-se completamente normais: TP (mediana: 100%) IQR (90-100); INR (mediana: 1,0) IQR (1,0-1,1); TTPa (mediana: 28,9 segundos) IQR (26,0-32,5) e TT (mediana: 18,2 segundos) IQR (17,0-19,5). Apenas (7/49) 14,3% pacientes apresentaram sangramento e (3/52) 5,8% necessitou de hospitalização. Não houve associação entre alterações tromboelastométricas com sangramento ou hospitalização. CONCLUSÕES: Dengue representa um processo inflamatório intenso, mantendo níveis normais de fibrinogênio. Portanto, FIBTEM mantém-se normal promovendo boa formação do coágulo sem risco imediato de sangramento. Não houve correlação entre os achados tromboelastométricos com os exames convencionais de coagulação, sugerindo que testes viscoelásticos são exames mais sensíveis para análise de coagulopatia precoce nessa população / INTRODUCTION: Dengue is a prevalent and potentially fatal viral disease associated with plasma leakage and coagulopathy, though no information is available on thromboelastometric profile. We performed this study to analyze dengue fever patients with thrombocytopenia clot changes through point-ofcare thromboelastometry tests and standard coagulation tests. METHODS: This was an observational, transversal and cross sectional study conducted between April 6th and May 5th 2015 in São Paulo, Brazil, during a dengue outbreak. Thromboelastometry ROTEM® was performed in 53 patients with dengue and thrombocytopenia, in association with conventional coagulation tests: prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT), thrombin time (TT); platelet count, fibrinogen level, and d-dimer. A control group of 10 patients was established to compare thromboelastometry profiles. RESULTS: A total of 38 patients in 53 (71,7%) had abnormalities in INTEM, 29 in 53 (57,4%) in EXTEM. Conversely, FIBTEM was abnormal in 3/53 (5,7%). Statistical analysis revealed significant relation in those patients with impairment EXTEM and INTEM with lowered platelet (p=0,052) and (p=0,005) respectively and lowered fibrinogen levels (p=0,006) and (p=0,021) respectively. Control group (CG) had normal status in 10/10 (100%) of INTEM, EXTEM, FIBTEM analysis. EXTEM analysis demonstrated statistical differences between CG and dengue group: CT (p=0,044); CFT (p < 0,001); MCF (p < 0,001) and Alpha (p < 0,001). Normal levels of fibrinogen (median: 290) and high levels of ddimer (median: 1330) IQR (800-1840) were found. All patients (53/53) had platelet under 100 x 109/L (median 77 x 109/L) IQR (63-88). Standard coagulation tests were completely normal: PT (median: 100%) IQR (90-100); INR (median: 1,0) IQR (1,0-1,1); aPTT (median: 28,9 seconds) IQR (26.0- 32,5) and TT (median: 18,2 seconds) IQR (17,0-19.5). Only (7/49) 14,3% patients had bleeding manifestations and (3/52) 5,8% needed hospitalization. There was no association between altered thromboelastometry with bleeding manifestations or hospitalization. CONCLUSIONS: Dengue represents an intense inflammatory process, maintaining normal levels of fibrinogen. FIBTEM remains normal providing good clot strength without immediate bleeding risk. There were no correlation between thromboelastometry findings and standard coagulation exams, suggesting that viscoelastic tests are more sensible method to analyze early coagulation impairments in this population
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Exames convencionais da coagulação como variáveis preditoras da indicação de transfusão de plasma fresco congelado durante o transplante de fígado / Conventional coagulation assays as predictors of indication of fresh frozen plasma transfusion during liver transplantationMarinho, David Silveira 29 April 2015 (has links)
INTRODUÇÃO: sangramento por coagulopatia é problema comum durante o transplante hepático (TH). O uso adequado da monitorização da coagulação pode reduzir a transfusão de hemocomponentes, como o Plasma Fresco Congelado (PFC). Exames Convencionais da Coagulação (ECC), tais como Tempo de Protrombina (TP) e Tempo de Tromboplastina Parcial Ativada (TTPa), são os testes mais amplamente utilizados para monitorizar a coagulação durante o TH, mas algumas limitações têm sido apontadas acerca do seu uso em pacientes cirróticos. OBJETIVO: investigar o uso de ECC como variáveis preditoras da indicação de transfusão de PFC durante o TH em pacientes cirróticos. MÉTODO: analisou-se coorte histórica de 297 transplantes hepáticos com enxertos provenientes de doadores cadáveres. Foram incluídos receptores cirróticos de uma única instituição durante nove anos (2002-2010). A infusão profilática de ácido épsilon-aminocaproico (20 mg/kg/h) e outros pré-requisitos hemostáticos foram mantidos na cirurgia. O TP [expresso na forma de Percentual de Atividade da Protrombina (TP%) e de Relação Normalizada Internacional (INR)] e o TTPa foram medidos no pré-operatório e no fim de cada fase do TH. Os participantes só receberam transfusão de PFC quando se diagnosticou coagulopatia, independentemente dos resultados dos ECC. Os pacientes foram distribuídos em dois grupos, de acordo com a ocorrência de transfusão intraoperatória de PFC. Examinou-se o comportamento dos resultados dos ECC durante a cirurgia. Analisaram-se os fatores de risco para a transfusão de PFC por análises uni e multivariada. Os resultados pós-operatórios de ambos os grupos foram comparados. A acurácia dos ECC para predizer o uso de PFC em cada fase da cirurgia foi investigada por curvas ROC. Além disso, pontos de corte dos ECC não associados à coagulopatia foram calculados para cada fase da cirurgia. RESULTADOS: a análise multivariada demonstrou que hematócrito pré-operatório (odds ratio [OR] = 0,90, P < 0,001), fibrinogênio pré-operatório (OR = 0,99, P < 0,001) e ausência de carcinoma hepatocelular (OR = 3,57, P = 0,004) foram as únicas variáveis preditoras independentes para a transfusão de PFC durante o TH. As mortalidades precoce e tardia, a permanência em UTI e a incidência de reoperações por sangramento microvascular foram semelhantes entre os grupos. Os ECC demonstraram baixa acurácia global para a predição de transfusão de PFC durante o TH (as áreas sob as curvas ROC não chegaram a 70%, independentemente do teste da coagulação e do momento da aferição). Pontos de corte de ECC com alta especificidade para a não transfusão de PFC foram determinados em cada fase do TH para TP% (39,4, 27,8 e 20,3), INR (2,14, 2,62 e 3,52) e TTPa (50,5, 80,2 e 119,5 segundos). CONCLUSÕES: os únicos preditores independentes para a transfusão de PFC durante o TH foram hematócrito pré-operatório, fibrinogênio pré-operatório e ausência de carcinoma hepatocelular. Os ECC demonstraram baixa correlação com a transfusão intraoperatória de PFC, independentemente do momento da coleta ou dos pontos de corte adotados / BACKGROUND & AIMS: Bleeding due to coagulopathy is a common problem during liver transplantation (LT). Coagulation monitoring may reduce transfusion of blood components, including Fresh Frozen Plasma (FFP). Conventional coagulation assays (CCA), like Prothrombin Time (PT) and Activated Partial Thromboplastin Time (aPTT), are the most widely employed tests to monitor coagulation during LT, but some limitations have been assigned to their use in cirrhotic patients. This study investigated the predictive value of these blood coagulation tests in predicting FFP transfusions during LT in cirrhotic patients. METHODS: This historical cohort study analyzed 297 isolated, deceased donor LTs performed in cirrhotic patients from a single institution during a nine-year period (2002 - 2010). Prophylactic infusion of epsilon-aminocaproic acid [EACA] (20 mg/kg/h) and other hemostatic requirements were maintained intraoperatively. PT [expressed as Activity Percentage (PT%) and International normalized ratio (INR)] and aPTT [expressed in seconds] were measured preoperatively and by the end of each phase of LT. Hemostatic blood components were transfused only in case of coagulopathy. Patients were divided in two groups according to intraoperative FFP transfusion: FFP group and Non-FFP group. Behavior of CCA results during LT were examined in both groups. Univariate and multivariate analyses of risk factors associated with FFP transfusion were performed. Post-operative outcomes were compared between groups. Accuracy of CCA to predict FFP transfusions was investigated using receiver operating characteristic (ROC) curves. Also, alert values of CCA unassociated with coagulopathy in each phase of surgery were calculated. RESULTS: Multivariate analysis showed that preoperative hematocrit (odds ratio [OR] = 0.90, P < 0.001), preoperative fibrinogen (OR = 0.99, P < 0.001) and absence of hepatocellular carcinoma (OR = 3.57, P = 0.004) were the only significant predictors for FFP transfusion. Short- and long-term survival, ICU stay and incidence of early reoperations for bleeding were similar between the groups. CCA demonstrated poor overall accuracy for predicting FFP transfusions (area under the ROC curves did not reach 0.70, irrespective of assay and of phase of sampling). High-specificity values of CCA unassociated with coagulopathy in each of 3 phases of LT were identified for INR (2.14, 2.62 and 3.52), PT% (39.4, 27.8 and 20.3%) and aPTT (50.5, 80.2 and 119.5 seconds). CONCLUSIONS: the only significant predictors for FFP transfusion were preoperative hematocrit, preoperative fibrinogen and absence of hepatocellular carcinoma. CCA, regardless of adopted cutoffs and of time of sampling during LT, have poor correlation with intraoperative FFP transfusion
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Exames convencionais da coagulação como variáveis preditoras da indicação de transfusão de plasma fresco congelado durante o transplante de fígado / Conventional coagulation assays as predictors of indication of fresh frozen plasma transfusion during liver transplantationDavid Silveira Marinho 29 April 2015 (has links)
INTRODUÇÃO: sangramento por coagulopatia é problema comum durante o transplante hepático (TH). O uso adequado da monitorização da coagulação pode reduzir a transfusão de hemocomponentes, como o Plasma Fresco Congelado (PFC). Exames Convencionais da Coagulação (ECC), tais como Tempo de Protrombina (TP) e Tempo de Tromboplastina Parcial Ativada (TTPa), são os testes mais amplamente utilizados para monitorizar a coagulação durante o TH, mas algumas limitações têm sido apontadas acerca do seu uso em pacientes cirróticos. OBJETIVO: investigar o uso de ECC como variáveis preditoras da indicação de transfusão de PFC durante o TH em pacientes cirróticos. MÉTODO: analisou-se coorte histórica de 297 transplantes hepáticos com enxertos provenientes de doadores cadáveres. Foram incluídos receptores cirróticos de uma única instituição durante nove anos (2002-2010). A infusão profilática de ácido épsilon-aminocaproico (20 mg/kg/h) e outros pré-requisitos hemostáticos foram mantidos na cirurgia. O TP [expresso na forma de Percentual de Atividade da Protrombina (TP%) e de Relação Normalizada Internacional (INR)] e o TTPa foram medidos no pré-operatório e no fim de cada fase do TH. Os participantes só receberam transfusão de PFC quando se diagnosticou coagulopatia, independentemente dos resultados dos ECC. Os pacientes foram distribuídos em dois grupos, de acordo com a ocorrência de transfusão intraoperatória de PFC. Examinou-se o comportamento dos resultados dos ECC durante a cirurgia. Analisaram-se os fatores de risco para a transfusão de PFC por análises uni e multivariada. Os resultados pós-operatórios de ambos os grupos foram comparados. A acurácia dos ECC para predizer o uso de PFC em cada fase da cirurgia foi investigada por curvas ROC. Além disso, pontos de corte dos ECC não associados à coagulopatia foram calculados para cada fase da cirurgia. RESULTADOS: a análise multivariada demonstrou que hematócrito pré-operatório (odds ratio [OR] = 0,90, P < 0,001), fibrinogênio pré-operatório (OR = 0,99, P < 0,001) e ausência de carcinoma hepatocelular (OR = 3,57, P = 0,004) foram as únicas variáveis preditoras independentes para a transfusão de PFC durante o TH. As mortalidades precoce e tardia, a permanência em UTI e a incidência de reoperações por sangramento microvascular foram semelhantes entre os grupos. Os ECC demonstraram baixa acurácia global para a predição de transfusão de PFC durante o TH (as áreas sob as curvas ROC não chegaram a 70%, independentemente do teste da coagulação e do momento da aferição). Pontos de corte de ECC com alta especificidade para a não transfusão de PFC foram determinados em cada fase do TH para TP% (39,4, 27,8 e 20,3), INR (2,14, 2,62 e 3,52) e TTPa (50,5, 80,2 e 119,5 segundos). CONCLUSÕES: os únicos preditores independentes para a transfusão de PFC durante o TH foram hematócrito pré-operatório, fibrinogênio pré-operatório e ausência de carcinoma hepatocelular. Os ECC demonstraram baixa correlação com a transfusão intraoperatória de PFC, independentemente do momento da coleta ou dos pontos de corte adotados / BACKGROUND & AIMS: Bleeding due to coagulopathy is a common problem during liver transplantation (LT). Coagulation monitoring may reduce transfusion of blood components, including Fresh Frozen Plasma (FFP). Conventional coagulation assays (CCA), like Prothrombin Time (PT) and Activated Partial Thromboplastin Time (aPTT), are the most widely employed tests to monitor coagulation during LT, but some limitations have been assigned to their use in cirrhotic patients. This study investigated the predictive value of these blood coagulation tests in predicting FFP transfusions during LT in cirrhotic patients. METHODS: This historical cohort study analyzed 297 isolated, deceased donor LTs performed in cirrhotic patients from a single institution during a nine-year period (2002 - 2010). Prophylactic infusion of epsilon-aminocaproic acid [EACA] (20 mg/kg/h) and other hemostatic requirements were maintained intraoperatively. PT [expressed as Activity Percentage (PT%) and International normalized ratio (INR)] and aPTT [expressed in seconds] were measured preoperatively and by the end of each phase of LT. Hemostatic blood components were transfused only in case of coagulopathy. Patients were divided in two groups according to intraoperative FFP transfusion: FFP group and Non-FFP group. Behavior of CCA results during LT were examined in both groups. Univariate and multivariate analyses of risk factors associated with FFP transfusion were performed. Post-operative outcomes were compared between groups. Accuracy of CCA to predict FFP transfusions was investigated using receiver operating characteristic (ROC) curves. Also, alert values of CCA unassociated with coagulopathy in each phase of surgery were calculated. RESULTS: Multivariate analysis showed that preoperative hematocrit (odds ratio [OR] = 0.90, P < 0.001), preoperative fibrinogen (OR = 0.99, P < 0.001) and absence of hepatocellular carcinoma (OR = 3.57, P = 0.004) were the only significant predictors for FFP transfusion. Short- and long-term survival, ICU stay and incidence of early reoperations for bleeding were similar between the groups. CCA demonstrated poor overall accuracy for predicting FFP transfusions (area under the ROC curves did not reach 0.70, irrespective of assay and of phase of sampling). High-specificity values of CCA unassociated with coagulopathy in each of 3 phases of LT were identified for INR (2.14, 2.62 and 3.52), PT% (39.4, 27.8 and 20.3%) and aPTT (50.5, 80.2 and 119.5 seconds). CONCLUSIONS: the only significant predictors for FFP transfusion were preoperative hematocrit, preoperative fibrinogen and absence of hepatocellular carcinoma. CCA, regardless of adopted cutoffs and of time of sampling during LT, have poor correlation with intraoperative FFP transfusion
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