Retrospective cohort study on the coagulation characteristics of adult patients with extensively severe burn in shock stage and its alarming value

Objective To study the coagulation characteristics of adult patients with extensively severe burn in shock stage and its alarming value. Methods Retrospective cohort study was performed on medical records of 37 adult patients with extensively severe burn who were admitted to the First Affiliated Hospital of Naval Medical University from January 2014 to December 2019 and met the inclusion criteria. The patients were divided into survival group (

=23, 17 males and 6 females, aged 41 (31, 51) years) and death group (

=14, 11 males and 3 females, aged 50 (43, 58) years) according to the prognosis of within 60 d after burn. Basic data of patients in the two groups and their routine coagulation indexes during shock period including prothrombin time (PT), thrombin time, activated partial thromboplastin time (APTT), D-Dimer, fibrinogen degradation product (FDP), fibrinogen, platelet, and international normalized ratio (INR) were recorded. Data were statistically analyzed with Wilcoxon rank sum test and Fisher′s exact probability test, prognosis-related factors was analyzed with single factor and multivariate logistic regression analysis (α selected=0.05, α excluded=0.1), and receiver operating characteristic (ROC) curve analysis were established to screen out the risk factors. All the patients were grouped into high score group and low score group according to the optimal threshold value, Kaplan-Meier method was used for survival analysis and Log-rank test was performed between the two groups. Results Total burn surface area (TBSA) of patients in death group was obviously larger than that in survival group (

=2.980,

<0.01), while there were no statistically significant difference in the other indexes between the two groups (

>0.05). Compared with those in survival group (16.10 (14.30, 16.90) s, 40.80 (36.20, 42.80) s, 1.30 (1.10, 1.40)), PT (18.70 (16.30, 22.70) s), APTT (46.45 (41.00, 57.10) s) and INR (1.55 (1.30, 1.96)) of patients in death group were significantly increased (

=2.540, 2.330, 2.300,

<0.05), there were no statistically significant difference in the other indexes between the two groups (

>0.05). Single factor logistic regression analysis showed TBSA, PT, and APTT were factors related to death of adult patients with extensively severe burn within 60 d after burn (odds ratio (OR)=1.190, 1.214, 1.109, 95% confidence interval (CI)=1.053-1.346, 1.008-1.461, 1.012-1.215,

<0.05 or

<0.01). FDP and INR were potential factors related to death of adult patients with extensively severe burn within 60 d after burn (OR=1.040 and 4.559, 95% CI =0.998-1.083 and 0.918-22.641,

<0.1). Multivariate logistic stepwise regression was used to build models of APTT+ FDP+ TBSA and APTT+ FDP. Area under the curve (AUC) of APTT+ FDP+ TBSA model score was 0.944 (95% CI= 0.873-1.000), which was higher than AUC of APTT+ FDP model score (0.843, 95% CI=0.713-0.973) by ROC curve analysis. Optimal threshold value of APTT+ FDP+ TBSA model score was -0.879 4 with sensitivity of 100% (95% CI=100%-100%) and specificity of 87% (95% CI=74%-100%). Survival ratio of patients in high score group with optimal threshold value higher than -0.879 4 was significantly lower than that in low score group with optimal threshold value lower than -0.879 4,

²=27.090,

<0.01. Conclusions The coagulation state of adult patients with extensively severe burn in shock stage is characterized with procoagulant and hemostatic dysfunctions accompanied by enhanced fibrinolytic activity. The risk of death is significantly increased in adult patients with extensively severe burn with APTT+ FDP+ TBSA model score higher than -0.879 4.