Objective:To prospectively investigate the prevalence of heparin-induced thrombocytopenia (HIT) in critically ill children during extracorporeal membrane oxygenation(ECMO) and explore the clinical characteristics and prognosis of HIT during ECMO.Methods:A total of 22 critically ill children, who had received ECMO support for more than 96 hours in the Intensive Care Unit at the Children′s Hospital of Fudan University from March 2019 to December 2020, were enrolled.According to the 4T score and the heparin/platelet factor 4(PF4) antibody, children whose 4T scores were not less than 6 and heparin/ PF4 antibodies were positive, were classified into HIT group ( n=6), and non-HIT group ( n=16). The clinical outcomes and the incidence of thrombotic events were compared between two groups. Results:The incidence of HIT during ECMO in critically ill children was 27% in this study.The incidence of thrombosis in the ECMO circuit in the HIT group was higher (100% vs.63%, P=0.133), and the average time to the first thrombosis in ECMO circuit in the HIT group was shorter than that in the non-HIT group (3.70 d vs.5.44 d, P=0.06). During the first 14 days of ECMO, the proportion of children with thrombotic events no less than twice was higher in the HIT group (67% vs.19%, P=0.054). There was no significant difference regarding the survival rate at 28 days after ECMO withdrawal between two groups (33% vs.50%, P=0.664). Conclusion:The prevalence of HIT during ECMO in critically ill children is high.Thrombosis events tend to occur earlier and more extensively in children with HIT during ECMO.No significant effect of HIT on the survival rate of children during ECMO is found.Whether HIT has effect on the survival rate of children with ECMO requires a prospective and large clinical study.

Objective:To investigate the correlation and consistency between the parameters of the thromboelastography(TEG) and of routine coagulation tests and platelet count(PLT) in critically ill children in the pediatric intensive care unit.Methods:We conducted a retrospective analysis on the results of the simultaneous TEGs, coagulation tests and PLT of 231 children in pediatric intensive care unit at Children′s Hospital Affiliated to Fudan University from March 2019 to July 2019, including the correlation analysis, the chi-square test and Kappa consistency analysis.Results:The reaction time(R) was linearly dependent on activated partial thromboplastin time(APTT), prothrombin time(PT) and thrombin time(TT), respectively.The maximal amplitude(MA), clot time formation(K) and alpha-angle(α) were linearly dependent on fibrinogen.The MA, K and α were linearly dependent on PLT, too.And the correlation between MA and PLT was the best( R=0.656). There were significant differences( P<0.001) and poor consistency(Kappa value: 0.112, 0.047, 0.124) between R and APTT, PT, TT.There was no significant difference( P>0.05) and there was moderate consistency(Kappa value: 0528, 0.518, 0.408) between Ma, K, α and PLT.There were significant differences( P<0.001) and the consistency was poor or fair(Kappa value: 0.324, 0.188, 0.170) between Ma, K, α and fibrinogen. Conclusion:TEG is significantly correlated with PLT in evaluating platelet function and the consistency is good.The TEG parameters are linearly correlated with the relevant results of routine coagulation tests in evaluating the coagulation factor and fibrinogen function, but consistency is weak.Therefore, it is concluded that these two methods are irreplaceable.