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BACKGROUND: Pathogen reduction technology (PRT) is increasingly used in the preparation of platelets for therapeutic transfusion. As the Czech Republic considers PRT, we asked what effects PRT may have on the recovery and function of platelets after cryopreservation (CP), which we use in both military and civilian blood settings. STUDY DESIGN AND METHODS: 16 Group O apheresis platelets units were treated with PRT (Mirasol, Terumo BCT, USA) before freezing; 15 similarly collected units were frozen without PRT as controls. All units were processed with 5-6% DMSO, frozen at - 80 °C, stored > 14 days, and reconstituted in thawed AB plasma. After reconstitution, all units were assessed for: platelet count, mean platelet volume (MPV), platelet recovery, thromboelastography, thrombin generation time, endogenous thrombin potential (ETP), glucose, lactate, pH, pO2, pCO2, HCO3, CD41, CD42b, CD62, Annexin V, CCL5, CD62P, and aggregates > 2 mm and selected units for Kunicki score. RESULTS: PRT treated platelet units had lower platelet number (247 vs 278 ×109/U), reduced thromboelastographic MA (38 vs 62 mm) and demonstrated aggregates compared to untreated platelets. Plasma coagulation functions were largely unchanged. CONCLUSIONS: Samples from PRT units showed reduced platelet number, reduced function greater than the reduced number would cause, and aggregates. While the platelet numbers are sufficient to meet the European standard, marked platelets activation with weak clot strength suggest reduced effectiveness.
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Remoção de Componentes Sanguíneos , Raios Ultravioleta , Humanos , Trombina , Preservação de Sangue , Plaquetas/fisiologia , Riboflavina/farmacologia , Ácido Láctico , CriopreservaçãoRESUMO
BACKGROUND: We present the case study of a 28-year-old pregnant woman with antithrombin deficiency who was treated with low-molecular-weight heparin (LMWH). METHODS: Due to severe homozygous type II antithrombin heparin binding site (HBS) deficiency, the thrombin generation (TG) was monitored in this woman via the Thrombin Generation Assay (TGA). We used Siemens diagnostic kits Berichrom® Antithrombin III (IIa) and INNOVANCE® Antithrombin (Xa) to determine antithrombin activity. We used a chromogenic method for determination of factor Xa (FXa) inhibition. RESULTS: There were no thrombotic complications during the whole pregnancy of the observed woman. Antithrombin was administered before and after delivery, which was significantly reflected in the decrease in thrombin generation. CONCLUSIONS: Consistent monitoring of thrombin generation with LMWH anticoagulant therapy administration during pregnancy together with antithrombin administration before and after delivery can improve the overall condition of pregnant women and the quality of their care.
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Deficiência de Antitrombina III , Antitrombinas , Feminino , Humanos , Gravidez , Adulto , Antitrombinas/uso terapêutico , Antitrombina III/farmacologia , Trombina , Gestantes , Heparina de Baixo Peso Molecular/uso terapêutico , Anticoagulantes/farmacologia , Heparina/farmacologia , Deficiência de Antitrombina III/diagnóstico , Deficiência de Antitrombina III/tratamento farmacológicoRESUMO
OBJECTIVES: There is a major problem in providing prophylactic treatment in antithrombin (AT)-deficient pregnant women with a homozygous mutation of the heparin binding site (HBS) and AT level of 17 %. The aim of the study was to determine the effectiveness of heparin by monitoring changes in thrombin generation (TG) in vitro so that pregnant women are not exposed to stress in vivo. METHODS: We used the chromogenic method for determination of factor Xa (FXa) inhibition for enoxaparine, nadroparine, dalteparine, fondaparinux and unfractionated heparin (UFH) and the Thrombin Generation Assay (TGA). RESULTS: We found that the degree of inhibition is very different when different heparins are compared. Nadroparin reduces TG the most compared to low molecular weight heparins (LMWH). CONCLUSION: Routine monitoring of anti FXa activity should be supplemented with TG monitoring, where the effect of LMWH does not manifest itself as this could help in estimating thrombophilic risk during pregnancy.
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WHAT IS KNOWN AND OBJECTIVE: Fondaparinux exhibits a similar mechanism of action as LMWH. Since both of these drugs bind to antithrombin and increase its affinity to factor Xa, fondaparinux is not expected to be an effective alternative anticoagulant to LMWH in case of LMWH resistance. CASE SUMMARY: We report on a case of effective anticoagulation using fondaparinux following total unresponsiveness to high doses of nadroparin administered twice daily, as confirmed via repeated anti-Xa measurements. The antithrombin levels were within the normal range. WHAT IS NEW AND CONCLUSION: To the best of our knowledge, this is the first report of the effective use of fondaparinux in the case of unresponsiveness to LMWH.
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Anticoagulantes/uso terapêutico , Fondaparinux/uso terapêutico , Heparina de Baixo Peso Molecular/uso terapêutico , Nadroparina/uso terapêutico , Idoso , Anticoagulantes/administração & dosagem , Anticoagulantes/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Fondaparinux/administração & dosagem , Fondaparinux/farmacologia , Heparina de Baixo Peso Molecular/administração & dosagem , Heparina de Baixo Peso Molecular/farmacologia , Humanos , Masculino , Nadroparina/administração & dosagem , Nadroparina/farmacologiaRESUMO
BACKGROUND: Surgery for benign disease is associated with a low-risk of developing venous thromboembolism (VTE). Despite a relatively low incidence of postoperative VTE in patients after elective cholecystectomy and abdominal hernia repair there are data proving hypercoagulability in the early postoperative period. We focused on assessment of the systemic inflammatory response and coagulation status in these surgical patients after hospital discharge. METHODS: Prospectively, patients who underwent surgery for benign disease were included. Two hundred sixteen patients were enrolled - 90 patients in laparoscopic cholecystectomy (LC) group and 126 patients in hernia surgery (HS) group. Risk assessment of VTE according to the Caprini risk assessment model was performed in all patients. Prevalence of VTE in postoperative period was observed. Markers of systemic inflammatory response (IL-6, CRP, α-1-acid glycoprotein, transferrin) and coagulation markers (PLT, fibrinogen, prothrombin fragment F1 + 2 and D-dimer) were measured before surgery, on 7-10th postoperative day and on 28-30th postoperative day. RESULTS: Clinically apparent deep vein thrombosis was diagnosed in only one patient - 0.46%. Statistically significant elevation of inflammatory markers IL-6, CRP and α-1-acid glycoprotein (p < 0.001; all) were proved in both groups of patients on 7-10th postoperative day. Statistically significant elevation of coagulation markers PLT, fibrinogen, prothrombin fragment F1 + 2 and D-dimer (p < 0.001; all) were proved in LC and HS groups on 7-10th postoperative day. No statistical difference was observed in IL-6, CRP and α-1-acid glycoprotein levels a month after surgery as compared with preoperative levels within each group. Statistically significant elevation of fibrinogen and prothrombin fragment F1 + 2 levels (p < 0.001; both) persisted on 28-30th postoperative day in both groups. Persisted elevation of D-dimer levels was proved only in HS group (p < 0.001), not in LC group (p = 0.138), a month after surgery. CONCLUSIONS: Activated systemic inflammatory response and hypercoagulable condition were verified in patients after laparoscopic cholecystectomy and hernia surgery after their hospital discharge. Hypercoagulability persisted even a month after surgery. Nevertheless, we observed very low prevalence of clinically apparent VTE in patients with in-hospital postoperative VTE prophylaxis. TRIAL REGISTRATION: Trials of the Czech Ministry of Health No. RVO-VFN64165 and NT 13251-4 .
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Colecistectomia Laparoscópica/efeitos adversos , Herniorrafia/efeitos adversos , Trombofilia/etiologia , Adulto , Idoso , Biomarcadores/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Estudos Prospectivos , Protrombina , Medição de Risco , Trombofilia/sangue , Trombofilia/diagnóstico , Adulto JovemRESUMO
There are presently new oral anticoagulants (NOAC) for prevention and the treatment of thromboembolic diseases and they are registered in CZ. It concerns of orally direct inhibitors of thrombin (dabigatran etexilate), inhibitors of factor Xa (apixaban, rivaroxaban), respectively, with advantage of some properties not being seen in "classical" anticoagulants. In the use of new anticoagulants, however, are some problems - such as laboratory monitoring in urgent situations of effective treatment and the absence of specific antidote - resolved. The text below brings indications, dosage of the drugs, their elimination, follow-up of efficacy of the treatment or risk of the bleeding as well as the therapy of bleeding complications.Key words: apixaban - dabigatran etexilate - NOAC - rivaroxaban.
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The cases of antithrombin (AT)-deficient pregnant women with a homozygous HBS II mutation are relatively rare and are accompanied by an increased thrombophilic risk, which is manifested by increased thrombin generation (TG). It is very difficult to ensure their prophylactic treatment during pregnancy. We aimed to determine the utility of the thrombin generation assay (TGA) and anti-factor Xa (anti-FXa) test to monitor the effects of a prophylactic dose of low-molecular-weight heparin (LMWH) in a 28-year-old woman with homozygous AT deficiency caused by mutation c.391C > T#, (p.Leu131Phe) in the SERPINC1 gene and to compare the findings with those from a group of pregnant and non-pregnant women also treated with LMWH. TG monitoring was chosen due to severe AT deficiency that was manifested by low levels of anti-FXa activity when monitoring the efficacy of LMWH treatment. A significant decrease in TG was detected in all monitored groups (P < .05). There were no thrombotic complications during the whole pregnancy of the woman with AT deficiency. Consistent monitoring of TG with LMWH anticoagulant therapy administration during pregnancy together with AT administration before and after delivery may improve the overall condition of pregnant women and the quality of their care.
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Deficiência de Antitrombina III , Heparina de Baixo Peso Molecular , Feminino , Humanos , Gravidez , Adulto , Gestantes , Trombina/uso terapêutico , Antitrombinas/uso terapêutico , Anticoagulantes/uso terapêutico , Antitrombina III , Deficiência de Antitrombina III/tratamento farmacológico , Deficiência de Antitrombina III/genética , MutaçãoRESUMO
BACKGROUND & AIMS: Wilson disease (WD) is an inherited disorder of copper disposition caused by an ATP7B transporter gene mutation, leading to copper accumulation in predisposed tissues. In addition to a genetic predisposition, other factors are likely to contribute to its clinical manifestation. The aim of the study was to assess whether oxidative stress affects the phenotypic manifestation of WD. METHODS: In 56 patients with WD (29 men; 26 with the hepatic form, 22 with the neurologic form, and eight asymptomatic; mean age 38.5 ± 12 years), total serum antioxidant capacity (TAC) and inflammatory parameters (hs-CRP, IL-1ß, IL-2, IL-6, IL-10, and TNF-α) were analyzed and related to the clinical manifestation, and mutations of the ATP7B gene. The control group for the TAC and inflammatory parameters consisted of 50 age- and gender-matched healthy individuals. RESULTS: WD patients had a significantly lower TAC (p < 0.00001), lower IL-10 levels (p = 0.039), as well as both higher IL-1ß (p = 0.019) and IL-6 (p = 0.005) levels compared to the control subjects. TNF-α, hs-CRP, and IL-2 did not differ from the controls. Patients with the neurological form of WD had a significantly lower TAC than those with the hepatic form (p < 0.001). In addition, the lower TAC was associated with the severity of the neurological symptoms (p = 0.02). No relationship between the inflammatory parameters and clinical symptoms was found. CONCLUSIONS: Data from our study suggest that the increased oxidative stress contributes significantly to the clinical manifestation of WD; as a lower TAC is associated with the neurological symptoms in WD patients.
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Adenosina Trifosfatases/genética , Antioxidantes/metabolismo , Proteínas de Transporte de Cátions/genética , Degeneração Hepatolenticular/sangue , Mutação , Doenças do Sistema Nervoso/sangue , Adulto , Cobre/metabolismo , ATPases Transportadoras de Cobre , Feminino , Predisposição Genética para Doença , Humanos , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Masculino , Pessoa de Meia-Idade , Estresse OxidativoRESUMO
Oxidative stress and inflammation contribute significantly to atherogenesis. We and others have demonstrated that mildly elevated serum bilirubin levels protect against coronary and peripheral atherosclerosis, most likely due to the antioxidant and anti-inflammatory activities of bilirubin. The aim of the present study was to assess serum bilirubin and the markers of oxidative stress and inflammation in both healthy subjects and patients with various forms of atherosclerosis. The study was performed in patients with premature myocardial infarction (n = 129), chronic ischemic heart disease (n = 43), peripheral artery disease (PAD, n = 69), and healthy subjects (n = 225). In all subjects, standard serum biochemistry, UGT1A1 genotypes, total antioxidant status (TAS), and concentrations of various pro- and anti-inflammatory chemokines were determined. Compared to controls, all atherosclerotic groups had significantly lower serum bilirubin and TAS, while having much higher serum high-sensitivity C-reactive protein (hsCRP) and most of the analyzed proinflammatory cytokines (p < 0.05 for all comparisons). Surprisingly, the highest inflammation, and the lowest antioxidant status, together with the lowest serum bilirubin, was observed in PAD patients, and not in premature atherosclerosis. In conclusion, elevated serum bilirubin is positively correlated with TAS, and negatively related to inflammatory markers. Compared to healthy subjects, patients with atherosclerosis have a much higher degree of oxidative stress and inflammation.
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BACKGROUND: Rivaroxaban represents a selective direct inhibitor of activated coagulation factor X (FXa) having peroral bioavailability and prompt onset of action. OBJECTIVE: The absorbtion of rivaroxaban is quick, reaching maximum plasma concentration 2-4 hours following its administration. Peroral bioavailability is high (80-100 %) and pharmacokinetic variability is considered to be moderate (coefficient of variation 30-40 %). This review discusses the properties, drug interactions, pharmacokinetics and clinical indications of rivaroxaban. METHOD: Dosing regimen of rivaroxaban was derived from pharmacologic data of the development program aimed to gain strong antithrombotic drug and balance between efficacy and risk of bleeding in patients. Results of doseranging trials, pharmacokinetic models and randomised studies of phase III advocate the use of such schemes in everyday practice. RESULTS: The drug has been manufactured to fulfill clinical requirements in a variety of indications in adults: prophylaxis of venous thromboembolism (VTE) following elective knee or hip replacement surgical intervention, therapy and secondary prophylaxis of VTE, prophylaxis of ischemic stroke and embolism in individuals diagnosed with nonvalvular atrial fibrillation (NVAF) with risky characteristics, and in Europe the prophylaxis of atherothrombotic episodes following an acute coronary syndrome in subjects with increased levels of cardiac biomarkers. CONCLUSION: Rivaroxaban may offer benefit in many clinical situations. In comparison with low molecular weight heparin and fondaparinux requiring subcutaneous way of administration, and with vitamin K antagonists (VKAs), which require regular monitoring of international normalized ratio, rivaroxaban is relatively easy to use. However, adjustments of dose are needed in individuals with impaired renal functions.
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Inibidores do Fator Xa , Rivaroxabana , Interações Medicamentosas , Inibidores do Fator Xa/farmacocinética , Inibidores do Fator Xa/farmacologia , Humanos , Rivaroxabana/farmacocinética , Rivaroxabana/farmacologiaRESUMO
BACKGROUND: Contemporary continuous-flow left ventricular assist devices (CF-LVADs) are associated with degradation of von Willebrand factor (vWF) high-molecular-weight multimers (HMWMs), a critical factor supporting platelet function. We hypothesized that the HeartMate 3 fully magnetically levitated LVAD, designed to reduce circulatory shear stress, favorably influences these hemostatic parameters. METHODS: Fifteen consecutive HeartMate 3 LVAD patients were compared with 11 consecutive HeartMate II controls. Serial plasma samples were collected pre-implant and on Days 2, 7, 30 and 45 post-operatively. Changes in vWF HMWMs were evaluated by 2 independent, study-blind hematologists and confirmed using densitometry-based computerized software. Ristocetin cofactor (RiCO) and vWF antigen (vWF Ag) were measured using standard protocols with enzyme-linked immunosorbent assay. RESULTS: HeartMate 3 patients and HeartMate II controls had a mean age of 67.3 ± 1.4 and 52.8 ± 2.5 years, respectively (INTERMACS Profiles 2 to 4 in 93.3% and 91%, respectively). HeartMate 3 group demonstrated a significantly greater preservation of HMWMs compared with the HeartMate II group, with the most prominent decrease occurring by Day 2 post-operatively and sustained through 45 days (71.94% vs 31.16%, p = 0.001). Laboratory values (normalized to baseline) for RiCO activity, vWF Ag and RiCO:vWF Ag ratio remained in the functional range with no statistically significant differences observed between groups. CONCLUSION: The HeartMate 3 LVAD is associated with enhanced hemocompatibility compared with the HeartMate II LVAD, as demonstrated by the improved preservation of vWF HMWMs, In contrast, effects on HMWM degradation appeared to be dissociated from functional attributes. Further confirmation of these findings in randomized clinical trials is warranted.
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Insuficiência Cardíaca , Ensaio de Imunoadsorção Enzimática , Coração Auxiliar , Humanos , Pessoa de Meia-Idade , Estresse Mecânico , Doenças de von Willebrand , Fator de von WillebrandRESUMO
Hip trauma and surgery are associated with systemic inflammatory reaction. However, little evidence exists about the role of IL-6. In order to assess the inflammatory response, we evaluated white blood cell (WBC) count, C-reactive protein (CRP) and IL-6 dynamics in sequential pre- and postsurgical samples collected from 125 elderly patients (mean age 78+/-9 years) undergoing osteosynthesis (OS) for extracapsular hip fractures (n=69), hemiarthroplasty (HA) or urgent total hip arthroplasty for intracapsular fractures (UA) (n=35), and elective total hip arthroplasty for osteoarthrosis (OA) (n=21). Both preoperative CRP and IL-6 levels were higher in patients with intracapsular fractures. IL-6 levels reached peak values immediately after the surgery, while CRP peak levels were reached 48 h after the surgery. The overall inflammatory reaction was more intense in HA patients compared to the other subgroups. Independent of each other, older age and the hip fracture type affected the IL-6 response, while the CRP response depended only on the type of surgery. The abrupt increase in IL-6 immediately after the procedure suggests its involvement in the early stages of the postoperative inflammatory reaction after hip surgery. This reaction is particularly pronounced in elderly patients receiving HA.
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Fraturas do Quadril , Inflamação , Interleucina-6/metabolismo , Procedimentos Cirúrgicos Operatórios/classificação , Procedimentos Cirúrgicos Operatórios/estatística & dados numéricos , Idoso , Feminino , Fraturas do Quadril/metabolismo , Fraturas do Quadril/mortalidade , Fraturas do Quadril/cirurgia , Humanos , Inflamação/epidemiologia , Inflamação/metabolismo , Inflamação/patologia , Masculino , Complicações Pós-Operatórias , Taxa de SobrevidaRESUMO
The objective of our study was to examine the changes in coagulation parameters and inflammatory reaction over the course of 15 days in patients with severe sepsis. We tried to identify mechanisms by which sepsis-induced pathophysiological changes may influence the effectiveness of subcutaneously (SC) administered enoxaparin 40 mg once daily. A total of 16 patients (8 men, 8 women; age 35-83 years) meeting the inclusion criteria of severe sepsis were enrolled in this study. The follow-up was performed on days 1, 2, 3, 6, 9, 12, and 15 of hospitalization at the intensive care unit (ICU). Blood coagulation (activated partial thromboplastin time [aPTT], prothrombin time [PT], fibrinogen, antithrombin (AT), protein C [PC], D-dimer, fragment 1.2 [F1.2], factor Xa [FXa] inhibition) and inflammatory reactants (interleukin 6 [IL-6], C-reactive protein [CRP], orosomucoid, alpha-1-antitrypsin) were tested. The mean FXa inhibition was 0.17 (+ or - 0.17) IU/mL. The arbitrarily established range of FXa inhibition for prophylaxis, 0.2 to 0.4 IU/mL, was reached in 22 cases (20%), while in 74 cases (68%), it was below and in 13 cases (12%) above the aforementioned range. Factor Xa inhibition positively correlated with AT (r = .42; P < .001) and PC (r = .45; P < .001) activities. A negative correlation was found between the FXa inhibition and alpha-1-antitrypsin concentrations (r = -.33; P = .01) but only in the subgroup with alpha-1-antitrypsin concentrations > or = 2.2 g/L. We confirmed that in most patients with sepsis, the prophylaxis with enoxaparin did not lead to the required FXa inhibition. The inhibition of FXa by enoxaparin depends mainly on the AT and PC activities.
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Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Enoxaparina/uso terapêutico , Inibidores do Fator Xa , Sepse/sangue , Trombose Venosa/sangue , Trombose Venosa/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: The capacity of mononuclear blood cells to form autoreactive cytotoxic T lymphocytes was investigated in order to elucidate the mechanism of successful immunosuppressive therapy in some myelodysplastic syndrome (MDS) patients (autoreactivity studies). The failure in autoreactivity studies raised the question of alloreactive cytotoxic T lymphocyte formation in MDS (alloreactivity studies). MATERIALS AND METHODS: Sixteen MDS patients and relevant controls were examined. Autoreactive lymphocytes directed against autologous bone marrow mononuclear cells and alloreactive lymphocytes directed against unrelated third-party cells were tested using cytotoxicity assay. In addition, we used one-way mixed lymphocyte reaction, human androgen receptor test for clonality detection, and enzyme-linked immunosorbent assay kits for tumor necrosis factor and interferon-gamma testing. RESULTS: We did not confirm the presence of autoreactive T cells in eight of nine MDS patients tested. The response to allogeneic cells was impaired in 11 of 16 MDS patients, more often in refractory anemia (RA; 80%) than in RA with ring sideroblasts (40%). Interestingly, the response to allogeneic cells in mixed lymphocyte reaction was normal in all MDS patients. T lymphocytes were polyclonal in all but one patient. Tumor necrosis factor and interferon-gamma level in supernatants of mononuclear cells was significantly reduced in RA. CONCLUSION: The presumed autoaggressive T cells were not confirmed in MDS in our experimental arrangement. Alloreactivity studies demonstrated the impairment of effector cytotoxic phase of cell-mediated immunological reaction in MDS, namely in RA. The significance of our finding of defective cytotoxicity for pathogenesis, clinical course, and even for therapy is discussed together with other immunological defects reported so far.
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Autoimunidade , Síndromes Mielodisplásicas/imunologia , Linfócitos T Citotóxicos/imunologia , Anemia Refratária/imunologia , Anemia Refratária com Excesso de Blastos/imunologia , Estudos de Casos e Controles , Células Clonais , Humanos , Imunidade , Leucócitos/patologia , Síndromes Mielodisplásicas/patologiaRESUMO
Twenty-three patients with fondaparinux prophylaxis over 75 years of age who underwent hip fracture surgery were enrolled in the study. Fondaparinux sodium (2.5 mg) was administered subcutaneously 6 h postoperatively and then every 24 h for 28 days. Coagulation and inflammatory parameters were measured preoperatively, then 10 h, 2, 7, and 28 days postoperatively. Increased D-dimers, positive acute phase proteins, and IL-6, and decreased negative acute phase proteins were observed preoperatively (P < 0.05). Maximum values were reached 10 h postoperatively for IL-6 and D-dimer, and on postoperative days 2 and 7 for positive acute phase proteins (P < 0.05). Transferrin, prealbumin and antithrombin levels were lowest 10 h postoperatively and on postoperative day 2 (P < 0.05). Increased D-dimers, IL-6, and positive acute phase proteins, and decreased negative acute phase proteins persisted until postoperative day 28 (P < 0.05). Prothrombin fragments (F1 + 2) reached peak levels preoperatively and decreased gradually until postoperative day 28. Fondaparinux promoted the inhibition of thrombin generation, as documented by negative correlation between F1 + 2 and FXa inhibition (r = -0.46; P < 0.001). Fondaparinux-induced FXa inhibition increased gradually until postoperative day 28. This increase correlated positively with antithrombin activity (r = 0.4; P < 0.05). Fondaparinux prophylaxis counteracted pro-thrombogenic effect associated with hip fracture and subsequent surgery without severe bleeding complications.