Assessment of Fibrinolysis in Sepsis Patients with Urokinase Modified Thromboelastography

<div><p>Introduction</p><p>Impairment of fibrinolysis during sepsis is associated with worse outcome. Early identification of this condition could be of interest. The aim of this study was to evaluate whether a modified point-of-care viscoelastic hemostatic assay can detect sepsis-induced impairment of fibrinolysis and to correlate impaired fibrinolysis with morbidity and mortality.</p><p>Methods</p><p>This single center observational prospective pilot study was performed in an adult Intensive Care Unit (ICU) of a tertiary academic hospital. Forty consecutive patients admitted to the ICU with severe sepsis or septic shock were included. Forty healthy individuals served as controls. We modified conventional kaolin activated thromboelastography (TEG) adding urokinase to improve assessment of fibrinolysis in real time (UK-TEG). TEG, UK-TEG, plasminogen activator inhibitor (PAI)-1, thrombin-activatable fibrinolysis inhibitor (TAFI), d-dimer, DIC scores and morbidity (rated with the SOFA score) were measured upon ICU admission. Logistic regression was used to calculate odds ratios (ORs) and 95% confidence intervals (95% CIs) of mortality at ICU discharge.</p><p>Results</p><p>UK-TEG revealed a greater impairment of fibrinolysis in sepsis patients compared to healthy individuals confirmed by PAI-1. TAFI was not different between sepsis patients and healthy individuals. 18/40 sepsis patients had fibrinolysis impaired according to UK-TEG and showed higher SOFA score (8 (6–13) vs 5 (4–7), p = 0.03), higher mortality (39% vs 5%, p = 0.01) and greater markers of cellular damage (lactate levels, LDH and bilirubin). Mortality at ICU discharge was predicted by the degree of fibrinolysis impairment measured by UK-TEG Ly30 (%) parameter (OR 0.95, 95% CI 0.93–0.98, p = 0.003).</p><p>Conclusions</p><p>Sepsis-induced impairment of fibrinolysis detected at UK-TEG was associated with increased markers of cellular damage, morbidity and mortality.</p></div

Distribution of MA and Ly30 measured by TEG and UK-TEG in healthy individuals and sepsis patients.

<p>Column scatter-plot for TEG_MA (Panel A), UK-TEG_MA (Panel B), TEG_Ly30 (Panel C) and UK-TEG_Ly30 (Panel D) in healthy individuals (circles) and sepsis patients (squares). Filled squares represent sepsis patients with SOFA score ≤ 10 (lower severity of disease), clear squares represent sepsis patients with SOFA score > 10 (higher severity of disease). Horizontal lines represent median (25^th- 75^th). * p<0.05, *** p<0.001, p value from Mann-Whitney test. TEG_MA, MA measured by TEG, UK-TEG_MA, MA measured by UK-TEG, TEG_Ly30, Ly30 measured by TEG, UK-TEG_Ly30, Ly30 measured by UK-TEG.</p

Characteristics of healthy individuals and sepsis patients.

<p>*From Mann-Whitney (continuous variables) or Fisher’s exact test (categorical variables).</p><p>Numbers in table refer to median (25^th– 75^th) or N(%). Abbreviations: SOFA, Sequential Organ Failure Assessment; DIC, disseminated intravascular coagulation; ISTH, International Society of Thrombosis and Haemostasis; JAAM, Japanese Association for Acute Medicine. Gram-positive microorganisms were: Methicillin Resistant Staphilococcus Aureus, Methicillin Subsceptible Staphilococcus Aureus, Enterococcus, Streptococcus Pyogenes, Streptococcus Pneumoniae. Enterobacteriae were: Escherichia Coli, Enterobacter, Serratia Marcescens. Other gram-negative bacilli were: Acynetobacter, Legionella Pneumophila. Virus was H1N1 influenza A virus.</p><p>Characteristics of healthy individuals and sepsis patients.</p

Clinical and laboratory parameters of sepsis patients in “normal response to UK” group and in “low response to UK” group.

<p>*P value from Mann-Whitney (continuous variables) or Fisher’s exact test (categorical variables). Numbers in table refer to median (25^th– 75^th) or N(%). Low response to UK group is defined as those patients with UK-TEG_Ly30 value less than 64.9% (limits of normality of healthy individuals UK-TEG_Ly30 = 64.9%-100%).</p><p>Abbreviations: SOFA, Sequential Organ Failure Assessment; LDH, lactate dehydrogenase; DIC, disseminated intravascular coagulation; MAP, mean arterial pressure; Hb, hemoglobin; ScvO₂, central venous oxygen saturation; SpO2, pulse oximetry.</p><p>Clinical and laboratory parameters of sepsis patients in “normal response to UK” group and in “low response to UK” group.</p

Graphical representation of two typical thromboelastographic tracings and parameters in a healthy individual (a) and a sepsis patient (b).

<p>TEG (dashed line) and UK-TEG (solid line) performed adding UK at a concentration of 80 IU/mL Abbreviations: r, reaction time; α, angle α; MA, maximal amplitude; Ly30, lysis at 30 min from MA.</p

Correlation between different methods for assessing fibrinolysis in sepsis patients.

<p>Panel A: Correlation between PAI-1 Activity (ng/ml) and UK-TEG_Ly30 (%), Spearman's rho = -0.13, p = 0.44. Panel B: Correlation between PAI-1 Antigen (ng/ml) and UK-TEG_Ly30 (%), Spearman’s rho = -0.06, p = 0.72. Filled circles represent sepsis patients with SOFA score ≤ 10 (lower severity of disease), clear circles represent sepsis patients with SOFA score > 10 (higher severity of disease). PAI-1, Plasminogen Activator Inhibitor 1; UK-TEG_Ly30, Ly30 measured by UK-TEG.</p

Coagulation and TEG parameters in healthy individuals, sepsis patients with “normal response to UK” and sepsis patients with “low response to UK”.

<p>*P value from Kruskal-Wallis rank test. Post-hoc multiple comparison analyses from Dunn’s test with Bonferroni correction,</p><p>^° low responders vs normal responders p<0.05;</p><p>^°° low responders vs normal responders p<0.001;</p><p>^§ low responders vs healthy individuals p<0.05;</p><p>^§§ low responders vs healthy individuals p<0.001;</p><p>^{^} normal responders vs healthy individuals p<0.05;</p><p>^{^^} normal responders vs healthy individuals p<0.001.</p><p>Numbers in table refer to median (25^th– 75^th). Low response to UK group is defined as those patients with UK-TEG_Ly30 value less than 64.9% (limits of normality of healthy individuals UK-TEG_Ly30 = 64.9%-100%).</p><p>Abbreviations: PT ratio, prothrombin time ratio; aPTT ratio, activated partial thromboplastin time ratio; PAI-1, Plasminogen Activator Inhibitor 1; TAFI, Thrombin Activatable Fibrinolysis Inhibitor; TEG, Thromboelastography; TEG_r, reaction time measured by TEG; TEG_angle, angle α measured by TEG; TEG_MA, maximum amplitude measured by TEG; TEG_Ly30, lysis at 30 minutes after MA measured by TEG; UK-TEG, urokinase kaolin activated thromboelastography, UK-TEG_r, reaction time measured by UK-TEG; UK-TEG_angle, angle α measured by UK-TEG; UK-TEG_MA, maximum amplitude measured by UK-TEG; UK-TEG_Ly30, lysis at 30 minutes after MA measured by UK-TEG.</p><p>Coagulation and TEG parameters in healthy individuals, sepsis patients with “normal response to UK” and sepsis patients with “low response to UK”.</p

Predicted probability (risk) of death in relation with UK-TEG_Ly30 (%).

<p>Predicted probability (risk) of death in relation with UK-TEG_Ly30 (%).</p

Odds ratios (OR) and 95% confidence interval (95% CI) of death for different lysis parameters using logistic regression analysis.

<p>Odds ratios (OR) and 95% confidence interval (95% CI) of death for different lysis parameters using logistic regression analysis.</p

Online_supplement_777441 – Supplemental material for Effects of sodium citrate, citric acid and lactic acid on human blood coagulation

<p>Supplemental material, Online_supplement_777441 for Effects of sodium citrate, citric acid and lactic acid on human blood coagulation by Vittorio Scaravilli, Luca Di Girolamo, Eleonora Scotti, Mattia Busana, Osvaldo Biancolilli, Patrizia Leonardi, Andrea Carlin, Caterina Lonati, Mauro Panigada, Antonio Pesenti and Alberto Zanella in Perfusion</p