A Clinical Study Of Perioperative Coagulation Abnormalities And Individualized Anticoagulation In Children With Congenital Heart Disease

Development and Internal Validation of Model Predicting Postoperative Blood Loss Risk Among Children with Pulmonary Atresia Undergoing Cardiopulmonary BypassObjective To develop and internally validate nomogram predicting postoperative blood loss risk among pediatric patients with pulmonary atresia(PA)undergoing cardiopulmonary bypass(CPB).Methods All patients aged from 6 months to 6 years with PA who underwent surgery at Fuwai Hospital from June 2015 to December 2019 were selected.And the prediction nomogram model was developed in the training set based on the selected patients.The demographic characteristics and laboratory data from each enrolled patient were gathered.Postoperative blood loss was defined as a blood loss exceeding 20.0 ml/kg within the first 24 postoperative hours.The least absolute shrinkage and selection operator(LASSO)method was used to optimize feature selection for multivariate logistic regression analysis that was applied to build a nomogram composed of all the features selected in the LASSO algorithm.The concordance index(C-index),calibration plot,and decision curve analysis(DCA)were used to evaluate the discrimination,calibration,and clinical net benefit of the nomogarm,respectively.Finally,internal validation was performed using the bootstrap technique.Results Of the 66 pediatric patients in the training set,21(31.82%)and 45(68.18%)patients were assigned into bleeding group and non-bleeding group,respectively.The first postoperative 24-h blood loss in the bleeding group was significantly higher than that in the non-bleeding group during ICU stay(P=0.000).Multivariate logistic regression analysis showed that,the immediate postoperative prothrombin time(odds ratio=1.419,95%confidence interval:1.094-1.841,P=0.008),the immediate postoperative platelet count(odds ratio=0.985,95%confidence interval:0.973-0.997,P=0.015)and the immediate postoperative red blood cell(RBC)count(odds ratio=0.335,95%confidence interval:0.166-0.667,P=0.002)were independent predictors of postoperative blood loss risk.The model presented favorable calibration and good discrimination with satisfactory calibration curve and a C-index of 0.858(95%confidence interval:0.758-0.958).High C-index value of 0.837 was achieved in the internal validation.The DCA revealed that the nomogram was great clinical effect when intervention was decided among nearly the entire range of threshold probabilities.Conclusion We developed and internally validated an accurate nomogram to assist in the clinical decision-making concerning the presence of postoperative blood loss in pediatric patients with PA undergoing CPB.However,the nomogram should be endorsed by external validation before it can be recommended for routine practice.Activated Partial Thromboplastin Time-Based Monitoring of Unfractionated Heparin:Clinical Outcomes after Cavo-pulmonary Connections undergoing Cardiopulmonary BypassObjective To evaluate the clinical value of heparin monitoring protocol based on activated partial thromboplastin time(aPTT)in children after cavo-pulmonary connections undergoing cardiopulmonary bypass.Methods Children aged from 6 months to 6 years old who underwent bidirectional Glenn procedure or total cavo-pulmonary connection in our hospital from June 2018 to December 2019 were prospectively selected.All dose adjustments of unfractionated heparin were based on the heparin monitoring protocol guided by aPTT.According to whether the therapeutic anticoagulation could be achieved within 48 hours and the aPTT could always be maintained within the target range,the selected children were categorized into two groups:up-to-standard group and non-up-to-standard group.Univariate analysis was used to compare the perioperative clinical data between the two groups.Results A total of 50 children were selected and all were included in the final statistical analysis,including 27 cases(54%)in the up-to-standard group and 23 cases(46%)in the non-up-to-standard group.The aPTT of the non-standard group was shorter than that in the standard group at 24 hours and 48 hours after the administration of heparin.When heparin had administrated for 48 hours,the level of antithrombin III was lower in the up-to-standard group(P<0.05).The chest tube output in the up-to-standard group was less than that in the non-up-to-standard group within 24 hours(P<0.01)and 48 hours after surgery(P=0.014).Moreover,the total amount of fresh frozen plasma transfusion within 48 hours in the up-to-standard group was less than that in the non-up-to-standard group(P<0.01).However,there was no statistically significant difference in the heparin maintenance dose between the two groups.Conclusion The protocol of activated partial thromboplastin time-based unfractionated heparin monitoring proposed in this study may improve the clinical outcomes in children after cavo-pulmonary connections undergoing cardiopulmonary bypass.Correlation between Different Anticoagulation Monitoring Assays and the Concentration of UFH during Extracorporeal Membrane Oxygenation in Children after Cardiac SurgeryObjective To evaluate the correlation of aPTT,ACT measurements and the activity of Anti-factor Xa assay with the concentration of UFH during ECMO in children after cardiac surgery.Methods The clinical data of children(aged 6 months to 6 years old)who received ECMO support after cardiac surgery in Fuwai Hospital from January 2010 to October 2020 were retrospectively collected.And record the aPTT value,ACT value,Anti-Xa activity and the corresponding UFH dose measured simultaneously during ECMO.According to the ELSO Anticoagulation guideline,the bleeding events of children during ECMO support were defined,and the children were divided into bleeding groups and non-bleeding groups according to whether bleeding events occurred.Pearson correlation was used to evaluate the correlation between ACT,aPTT or Anti-Xa activity measured simultaneously and UFH in the same patient.Results A total of 58 children,including 33 males and 25 females,aged 27.31 ±34.17 months,were enrolled and divided into bleeding group(n=39)and non-bleeding group(n=19)according to the definition of bleeding events.Univariate analysis showed that compared with children in the non-bleeding group,children in the bleeding group had lower red blood cell counts(P=0.049),hemoglobin concentration(P=0.010),and hematocrit(P=0.046)on the day of ECMO installation;In addition,the transfusions of fresh frozen plasma(P=0.034)and fibrinogen(P=0.033)in the bleeding group is relatively high,and the proportion of exploratory thoracotomy for hemostasis is significantly high(P=0.000);there is a moderate degree of correlation between Anti-Xa and UFH(r=0.418,P=0.013)but there is no correlation between ACT or aPTT and UFH.Conclusion The aPTT value and ACT value are poorly correlated with the concentration of UFH transfused during ECMO in children after cardiac surgery,while the Anti-Xa activity is moderately correlated with it.Value of Combining Activated Partial Thromboplastin Time with Activated Coagulation Time for Screening Bleeding Complications in Children during Extracorporeal Membrane Oxygenation after Cardiac SurgeryObjective To evaluate the efficiency of aPTT combined with ACT for screening bleeding complications in children during ECMO after cardiac surgery.Methods The clinical data of children(aged 6 months to 6 years old)who received ECMO support after cardiac surgery in Fuwai Hospital from January 2010 to October 2020 were retrospectively collected.The selected population usually measures aPTT and ACT at the same time every 1-3 hours during ECMO.Bleeding events in children during ECMO support were defined according to the ELSO anticoagulation guidelines.The Pearson correlation was used to evaluate the correlation between ACT and aPTT.And the linear by linear association method was used to analyze whether the combined indicator of ACT and aPTT has a linear trend with the bleeding events during ECMO.Logistic regression was used to combine the indicators of aPTT and ACT and the ROC was used to evaluate the sensitivity and specificity of the combined indicator in diagnosing bleeding complications in children during ECMO after cardiac surgery,and the AUC was calculated to evaluate its accuracy.Results A total of 58 children were enrolled and divided into bleeding group(n=39)and non-bleeding group(n=19)according to the definition of bleeding events.Univariate analysis showed that compared with children in the non-bleeding group,children in the bleeding group had lower red blood cell counts(P=0.049),hemoglobin concentration(P=0.010),and hematocrit(P=0.046)on the day of ECMO installation;In addition,the transfusions of fresh frozen plasma(P=0.034)and fibrinogen(P=0.033)in the bleeding group is relatively high,and the proportion of exploratory thoracotomy for hemostasis is significantly high(P=0.000);there is a moderate degree of correlation between ACT and aPTT(r=0.558,P=0.000);as the values of ACT and aPTT increase,there is a linear trend of bleeding events in the study population during ECMO(?2=165.240,P=0.000);the indicator of aPTT value combined with ACT value is used to screen bleeding events,and its AUC is equal to 0.757.Conclusion The aPTT combined with ACT is an effective method for screening bleeding complications in children during ECMO after cardiac surgery,and this method has good accuracy.