[Application of thromboelastogram in reasonable transfusion for hospitalixed patients with critically illness]

To discuss the application value of thromboelastogram (TEG) in reasonable use of blood in critical patients.

The data of 100 critical patients with potential need for massive blood transfusion admitted to the Third Xiangya Hospital of Central South University from July 2014 to August 2015 were analyzed retrospectively. Their blood samples were collected and routine parameters including coagulation functions and TEG were tested; the correlation among the above parameters was analyzed. Then the components and amount of blood products ordered before and after TEG were compared.The diagnostic sensitivity and specificity of TEG and conventional coagulation test for these patients were assessed.

There were 51 men and 49 women in the 100 critical patients, and their ages were between 35 to 70 years old with an average of (54.0 ± 12.5) years old. A positive correlation was found between prothrombin time (PT),activated partial thromboplastin time (APTT) and R value (r1 =0.380, P1 =0.010;r2 =0.490,P2 =0.002).Fibrinogen (FIB) was positively correlated with MA value (r =0.390,P =0.020),and negatively correlated with K value (r =-0.310,P =0.040).Blood platelet count (PLT) was positively correlated with α angle and MA value (r1 =0.510, P1 =0.002; r2 =0.650, P2 =0.001). Meanwhile, there was no significant correlated between D-Dimer and TEG results. We performed a TEG-CKH to test 22 samples again which were highly suspected having a residue of heparin after TEG-CK test. The result showed a dramatic decline of R value and K value [R value (minutes):11.4±4.9 vs.28.6±22.4,K value (minutes):4.4±2.7 vs.18.5± 14.7,both P ＜ 0.05],while α angle and MA value were increased [α angle (°):44.8± 17.2 vs.22.6± 18.8,MA value (mm):48.7± 15.8 vs.28.8±23.2,both P ＜ 0.05].There was a significant change in the cases, the components and the amount of blood products after retest [plasma, PLT and cryoprecipitate patients needed were changed from 18,7,3 to 5,7,5,respectively;the amount of plasma (mL) was decreased from 600.00±256.10 to 150.00±70.71 per patient, the PLT (U) was decreased from 1.00 ± 0.46 to 0.50 ± 0.28 per patient,the cryoprecipitate (U) was increased from 4.00 ± 0.99 to 8.60 ± 2.07 per patient, all P ＜ 0.05].There was significant difference in volume of blood products after and before TEG was used to guide blood transfusion in 78 patients without residue of heparin [the amount of plasma (mL) was decreased from 422.66 ± 197.79 to 241.67 ± 210.22 per patient, the PLT (U) was increased from 0.75 ± 0.38 to 1.60 ± 1.00 per patient, both P ＜ 0.05].The sensitivity of R value, K value,α angle, MA value, PT,APTY,FIB and PLT were 15.94％, 17.39％, 24.63％, 30.43％, 46.37％, 39.13％, 28.98％ and 47.83％,respectively,in diagnosis of bleeding, while the specificity were 87.09％, 80.65％, 77.42％, 74.19％, 64.52％, 74.19％, 80.64％ and 54.84％, respectively.

There was significant correlation between TEG parameters and indicators of conventional coagulation test, but either of them has advantage over the other, and cannot be replaced. TEG can be used to guide reasonable transfusion for critical patients, though other clinical and laboratory tests should be combined.