Value of thromboelastography in monitoring effect of hypothermia on coagulation function in major trauma patients

Abstract

Objective To investigate effect of hypothermia on coagulation function in major trauma patients and assess value of thromboelastography (TEG) monitoring.Methods Twenty-two patients with major trauma admitted to the emergency intensive care unit between January 2010 and June 2011 were enrolled in the study.The venous blood of the patients was sampled for TEG determination at different temperatures (37,35 and 33 ℃) to analyze variation of the indices including coagulation reaction time (R),clot formation time (K),rate of clot formation (Angle),maximum amplitude (MA)and coagulation index (CI).The patients were divided into normal coagulation group and abnormal coagulation group based on the CI value at 37 ℃ to analyze effects of temperature on TEG indices in both groups and their differences between groups.Results (1) Among 22 patients,TEG indices including R and K trended upward (P ＜ 0.01),but Angle,MA and CI trended downward (P ＜ 0.01) with decline of the temperatures.(2) K and Angle values,indicators of fibrinogen function,were obviously inhibited (P ＜ 0.05) with the temperature decreasing from 37 ℃ to 35 ℃,but other TEG indices had no significant changes.Whereas,all TEG indices were significantly inhibited when the temperature was decreased from 35 ℃ to 33 ℃.(3) There were significant differences in variation of each TEG index inhibited by hypothermia (P ＜ 0.01).All TEG indices showed significant differerces in the pairwise comparison,except for the differences between R and K as well as between Angle and MA (P ＜0.01).(4) R and K were increased,but Angle,MA and CI were decreased in both groups,with decline of the temperatures.Moreover,all TEG indices in the abnormal group were worse than those in the normal group.Conclusions Hypothermia has significant effect on coagulation function of patients with major trauma.TEG,which may be measured at any temperature,is more accurate in reflection of patients' actual coagulation function and is helpful for choice of an appropriate temperature in the mild hypothermia therapy. Key words: Wounds and injuries; Blood coagulation disorders; Hypothermia; Thromboelastography