Comparison of thrombelastometry with simplified acute physiology score II and sequential organ failure assessment scores for the prediction of 30-day survival: a cohort study

Abstract

Disseminated intravascular coagulation contributes to mortality of sepsis. The study was performed to investigate thromboelastometry as a potential predictor of 30-day survival in severe sepsis and to compare thromboelastometry to Simplified Acute Physiology Score II (SAPS II) and Sequential Organ Failure Assessment (SOFA) scores. Ninety-eight patients with severe sepsis were included in the cohort study. Thromboelastometry clotting time, clot formation time (CFT), maximum clot firmness (MCF), and α angle as well as SAPS II and SOFA scores were determined at the day of diagnosis. Thromboelastometry variables differed in survivors and nonsurvivors. Mean CFT was prolonged (276 ± 194 vs. 194 ± 109 s, P = 0.021; mean ± SD), and both MCF (52.7 ± 12.1 mm vs. 57.3 ± 11.5 mm, P = 0.042) and α angle (53.4 ± 12.8 degrees vs. 58.9 ± 11.8 degrees, P = 0.028) were reduced in nonsurvivors. Clotting time and SAPS II and SOFA scores were not different. Thromboelastometry values were classified as normal and pathological, respectively, using the median of the variables as the cutoff. Thromboelastometry values were normal if CFT was less than 185 s, MCF was greater than 55 mm, and α was greater than 57.5 degrees. Thirty-day survival was 85.7% when all thromboelastometry variables were normal, but 58.7% when at least one variable was pathological (P = 0.005). Multivariate analysis revealed that the absence or presence of at least one pathological thromboelastometry variable allows for better prediction of 30-day survival in severe sepsis than the SAPS II and SOFA scores (P = 0.01; odds ratio, 4.1), respectively, emphasizing the importance of the coagulation system in sepsis.