
==== Front
Singapore Med J
Singapore Med J
SMJ
Singapore Med J
Singapore Medical Journal
0037-5675
2737-5935
Wolters Kluwer - Medknow India

37077056
SMJ-65-438
10.4103/singaporemedj.SMJ-2021-404
Original Article
Thromboelastography parameters in chronic viral liver disease and liver resection: a retrospective study
Di Ying MD 1
Li Jialu MD 1
Ye Chunjuan MD 1
Wang Zheng MD, PhD 1
Zhu Qianqian MD, PhD 2
1 Department of Hepatobiliary Surgery, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an City, Shaanxi Province, China
2 Department of Anesthesiology, The Seventh Affiliated Hospital of Sun Yat-Sen University, Shenzhen City, People’s Republic of China
Correspondence: Dr. Qianqian Zhu, Department of Anesthesiology, The Seventh Affiliated Hospital of Sun Yat-Sen University, No. 628 Zhenyuan Road, Shenzhen, Guangdong Province - 518107, China. E-mail: zhuxx25@mail.sysu.edu.cn
8 2024
13 4 2023
65 8 438443
23 10 2021
26 7 2022
Copyright: © 2024 Singapore Medical Journal
2024
https://creativecommons.org/licenses/by-nc-sa/4.0/ This is an open access journal, and articles are distributed under the terms of the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 License, which allows others to remix, tweak, and build upon the work non-commercially, as long as appropriate credit is given and the new creations are licensed under the identical terms.
Introduction:

Thromboelastography (TEG) provides a global assessment of haemostasis and is potentially applicable to liver disease. The present study aimed to explore the utility of TEG for the evaluation of patients with chronic viral liver disease, which has previously not been investigated.

Methods:

Demographic characteristics and TEG parameters were collected before surgery. Child–Turcotte–Pugh (CTP) and model for end-stage liver disease (MELD) scores were used to categorise stages of liver cirrhosis. Liver resections were classified as low, medium and high complexity.

Results:

A total of 344 patients were included. Results showed significantly longer K-time, smaller α-angle and lower maximum amplitude (MA) with increasing liver disease severity as measured by the CTP and MELD scores (P < 0.05 for all). After multivariable adjustment (including age, sex, liver disease aetiology, alanine aminotransferase [ALT], aspartate aminotransferase [AST], albumin, total bilirubin, haemoglobin and platelet count), TEG parameters (except R-times) were either weakly or inversely related to the severity of liver disease as defined by the MELD score (absolute r < 0.2 and P < 0.05 for all except R-times). R-times obtained before surgery were weakly correlated with perioperative blood loss (r < 0.2 and P < 0.05 for all).

Conclusions:

The correlation between TEG parameters and severity of liver disease was weak. In addition, R-times obtained before liver resection were weakly associated with perioperative blood loss after multivariable adjustments. TEG utility for haemostasis assessment and prediction of blood loss during liver resection should be further explored in high-quality studies.

Chronic viral liver disease
liver resections
thromboelastography
==== Body
pmcINTRODUCTION

Chronic liver disease has been considered the major cause of acquired coagulation disorders.[1] However, the coagulopathy of chronic liver diseases is complex. Recent studies have demonstrated that blood coagulation in chronic liver disease, especially in liver cirrhosis, is rebalanced due to a parallel reduction of procoagulant and anticoagulant factors.[234] Reports showed that the von Willebrand factor (vWF) and factor VIII were increased in chronic liver disease, whereas antithrombin and protein C were decreased.[567] High plasma level of vWF compensates for a reduction in platelet count, and conventional coagulation tests such as prothrombin time (PT), international normalised ratio (INR) and activated partial thromboplastin time (APTT) measure only procoagulant factors. Consequently, these tests may not be suitable for evaluation of this potentially rebalanced state.[89]

Thromboelastography (TEG) is a tool for rapid global haemostasis assessment that provides effective quantification of platelet function, thrombus formation, clot tensile strength and fibrinolysis. TEG has been used to monitor perioperative changes in coagulation during surgery and to guide transfusion in liver transplants.[101112] Additionally, a previous study demonstrated that TEG parameters were associated with severity of cirrhosis,[13] but another study indicated that the association was weak.[14] Notably, the study groups in the aforementioned reports included patients with viral liver disease and those with primary biliary cirrhosis. TEG results showed that patients with primary biliary cirrhosis were relatively hypercoagulable compared to those with non-cholestatic liver disease.[15] To the best of our knowledge, no study has investigated the potential application of TEG for chronic viral liver disease, and the correlation between TEG results before surgery and blood loss during liver resection. Therefore, we conducted the present study to explore the utility of TEG for assessment of haemostasis in patients with chronic viral liver disease.

METHODS

This retrospective study was approved by the Ethics Committee of the First Affiliated Hospital of Xi’an Jiaotong University. The need for obtaining informed consent from participants was waived because of the retrospective nature of the study and the use of anonymised data.

The inclusion criteria for the study were as follows: adult patients; patients with chronic viral liver diseases; and TEG conducted before surgery or any blood transfusions. The exclusion criteria were as follows: patients with acute liver failure; alcoholic patients and those with primary biliary cirrhosis; liver transplant patients; and patients with liver rupture due to cancer. Three hundred and forty-four consecutive adult patients with chronic viral hepatitis from June 2015 to December 2019 were included. Demographic characteristics, such as patient age, sex and clinical characteristics, were analysed. Admission diagnosis, preoperative laboratory tests, abdominal ultrasound and/or computed tomography examination results and TEG parameters before surgery were collected.

Child–Turcotte–Pugh (CTP) and model for end-stage liver disease (MELD) scores were calculated from the laboratory values at hospital admission before TEG measurement or any treatment. Patients with liver cirrhosis were stratified into three classes (A, B and C) by the CTP score. Class A was defined as a CPT score of 5–6, class B as a CPT score of 7–9 and class C as a CPT score of 10–15. MELD score was calculated as follows: MELD = 3.78 × loge (bilirubin in mg/dL) + 11.2 × loge (INR) + 9.57 × loge (creatinine in mg/dL) + 6.43. Based on a previous study, the cut-off for the MELD score was 10 (<10 or ≥10).[10]

Liver disease severity refers to the severity of chronic viral liver disease including in non-cirrhotic patients. Liver resection was classified as low, medium or high complexity based on previous studies.[1617] The detailed classification of liver resection can be found in a previous study by Lee et al[18] [see Supplementary Table 1, Appendix].

Statistical analysis

Data were expressed as proportions, means and standard deviation. Continuous variables were evaluated with one-way analysis of variance, the Mann–Whitney U test or the Kruskal–Wallis test in different groups. Categorical variables were compared using the chi-square test when appropriate. For all statistical comparisons, a P value <0.05 was considered statistically significant. Statistical analyses were performed using IBM SPSS Statistics version 22.0 (IBM Corp, Armonk, NY, USA). A partial correlation test assessed the correlations of variables. The absolute r for correlation was defined as strong when it was 0.6–1.0. A moderate correlation was indicated when the absolute r was 0.4–0.59. An absolute r of 0.0–0.39 indicated a weak correlation. A negative r indicated a reverse correlation.

RESULTS

Characteristics of patients

Demographic, clinical and laboratory data of the included patients are shown in Table 1. The mean age of the 344 patients was 52.51 years, and 82.26% (n = 283) were male. Hepatitis B virus was the most prevalent aetiology of viral hepatitis (94.18%, n = 324), and hepatocellular carcinoma (HCC) was diagnosed in 328 patients (95.35%). Of the 344 patients, 292 patients were cirrhotic and 52 were non-cirrhotic.

Table 1 Clinical and laboratory characteristics of the patients.

Characteristic	Non-cirrhosis (n=52)	Cirrhosis	P	Non-cirrhosis (n=52)	Cirrhosis	P	
		
CTP A (n=238)	CTP B (n=54)	MELD <10 (n=220)	MELD ≥10 (n=72)	
Age (yr)	50.23±10.49	52.68±9.82	53.93±11.07	0.154	50.23±10.49	53.74±9.51	50.39±11.26	0.011	
	
Male gender	41 (78.8)	201 (84.5)	41 (75.9)	0.261	41 (78.8)	183 (83.2)	59 (81.9)	0.767	
	
Viral type									
	
 HBV	51 (98.1)	226 (95.0)	47 (8)	0.094	51 (98.1)	208 (94.5)	65 (90.3)	0.356	
	
 HCV	1 (1.9)	5 (2.1)	4 (7.4)		1 (1.9)	5 (2.3)	4 (5.6)		
	
 HBV + HCV	0	7 (2.9)	3 (5.6)		0	7 (3.2)	3 (4.2)		
	
 HCC	50 (96.2)	231 (97.1)	47 (87.0)	0.012	50 (96.2)	214 (97.3)	64 (88.9)	0.016	
	
ALT (U/L)	42.93±33.37	43.65±37.12	41.94±45.21	0.954	42.93±33.37	42.34±30.95	46.36±56.22	0.736	
	
AST (U/L)	44.94±28.85	45.62±34.89	45.69±40.84	0.991	44.94±28.85	43.60±31.74	51.84±46.36	0.220	
	
Albumin (g/L)	39.51±4.41	39.53±4.40	34.31±3.34	<0.001	39.51±4.41	38.98±4.55	37.29±4.88	<0.001	
	
Total bilirubin (µmol/L)	14.61±6.32	16.72±8.14	20.62±12.57	0.001	14.61±6.32	14.54±6.30	26.30±10.97	<0.001	
	
PT (s)	13.81±0.74	14.34±1.05	15.53±1.23	<0.001	13.81±0.74	14.14±0.80	15.84±1.21	<0.001	
	
APTT (s)	39.31±3.60	39.22±4.60	41.19±7.15	0.030	39.31±3.60	38.76±4.51	42.12±6.29	<0.001	
	
INR	1.08±0.07	1.13±0.11	1.25±0.12	<0.001	1.08±0.07	1.11±0.08	1.28±0.12	<0.001	
	
Hb (g/dL)	140.23±14.69	136.67±17.73	116.35±22.71	<0.001	140.23±14.69	135.52±17.65	124.96±25.37	<0.001	
	
PLT (109/L)	216.79±73.82	138.48±77.62	118.00±71.43	<0.001	216.79±73.82	143.74±76.08	107.07±72.79	<0.001	
	
Liver resection	49 (94.2)	218 (91.6)	46 (85.2)	0.490	49 (94.2)	207 (94.1)	57 (79.2)	0.045	
	
 Low complexity (n=28)	3 (6.1)	19 (8.7)	6 (13.0)		3 (6.1)	14 (6.8)	11 (19.3)		
	
 Medium complexity (n=263)	44 (89.8)	184 (84.4)	35 (76.1)		44 (89.8)	175 (84.5)	44 (77.2)		
	
 High complexity (n=22)	2 (4.1)	15 (6.9)	5 (10.9)		2 (4.1)	18 (8.7)	2 (3.5)		
Data are presented as either n (%) or mean±standard deviation. ALT: alanine aminotransferase, APTT: activated partial thromboplastin time, AST: aspartate aminotransferase, CTP: Child–Turcotte–Pugh, Hb: haemoglobin, HBV: hepatitis B virus, HCC: hepatocellular carcinoma, HCV: hepatitis C virus, INR: international normalised ratio, MELD: model for endstage liver disease, PT: prothrombin time, PLT: platelet count

The CTP score classification identified 238 CTP A-class patients and 54 CTP B-class patients. No significant differences due to age, sex or aetiology were observed among patients in the non-cirrhotic group or among patients with cirrhosis of different severities at baseline (all P > 0.05) [Table 1]. The MELD score classification identified 220 liver cirrhosis patients with MELD scores <10 and 72 patients with MELD scores ≥10. Except for age (P = 0.011) [Table 1], no significant differences were observed among patients in the non-cirrhotic group or among patients with cirrhosis of different severities at baseline. No significant differences were observed due to sex or aetiology (all P > 0.05) [Table 1].

Patients with more severe liver disease had lower haemoglobin concentrations (P < 0.001) and platelet counts (P < 0.001) as determined by both CTP and MELD scoring systems [Table 1].

TEG parameters and severity of chronic viral liver disease

CTP score classes

Except for R-times, all other TEG parameters significantly trended towards longer K-times, smaller α-angles, lower maximum amplitude (MA) and smaller confidence interval (CI) with increased liver disease severity (all P < 0.05) [Table 2]. However, the correlation between the TEG parameters and the severity of chronic liver disease or liver cirrhosis revealed no significant means after adjusting the following variables in Table 1: age, sex, liver disease aetiology, alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total bilirubin, haemoglobin and platelet count (all P > 0.05) [Table 2].

Table 2 Thromboelastography parameters in severity of chronic viral hepatitis according to CTP scores.

Parameter	Non-cirrhosis (n=52)	Cirrhosis	P trend	Severity of chronic liver disease correlation coefficient*a	P	Severity of liver cirrhosis correlation coefficient*b	P	
	
CTP A (n=238)	CTP B (n=54)	
R-time (min)	5.51±1.08	5.65±1.39	5.64±1.14	0.614	0.057	0.303	0.067	0.264	
	
K-time (min)	1.87±0.82	2.53±1.34	2.54±1.14	0.007	0.049	0.377	0.012	0.839	
	
α-angle (°)	65.08±7.73	60.25±9.15	60.63±9.30	0.011	−0.078	0.153	−0.059	0.326	
	
MA (mm)	62.26±6.66	55.67±8.45	54.27±9.32	<0.001	−0.107	0.051	−0.082	0.168	
	
CI	0.47±2.14	−0.99±2.59	−1.03±2.71	0.003	−0.089	0.105	−0.068	0.257	
*Adjusted for variables such as age, sex, liver disease aetiology, alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin, haemoglobin and platelet count. aIncluding non-cirrhosis. bExcluding non-cirrhosis. CI: confidence interval, CTP: Child–Turcotte–Pugh, MA: maximum amplitude

MELD score classes

Similar to the CTP score classes, the MELD scores for all the TEG parameters (except R-times) also showed a significant trend towards longer K-times, smaller α-angles, lower MA and smaller CI (all P < 0.05) [Table 3] with increased liver disease severity. Furthermore, after multivariable adjustment, the TEG parameters (except R-times) were still weakly or inversely correlated to liver disease severity or liver cirrhosis according to the MELD scores after adjustment (all absolute r < 0.2) [Table 3].

Table 3 Thromboelastography parameters in severity of chronic viral hepatitis according to MELD scores.

Parameter	Non-cirrhosis (n=52)	Cirrhosis	P trend	Severity of chronic liver disease correlation coefficient*a	P	Severity of liver cirrhosis correlation coefficient*b	P	
	
MELD <10 (n=220)	MELD ≥10 (n=72)	
R-time (min)	5.51±1.08	5.60±1.39	5.77±1.25	0.280	0.073	0.184	0.104	0.083	
	
K-time (min)	1.87±0.82	2.36±1.01	3.06±1.86	<0.001	0.141	0.010	0.134	0.025	
	
α-angle (°)	65.08±7.73	61.26±8.33	57.45±10.92	<0.001	−0.148	0.007	−0.159	0.008	
	
MA (mm)	62.26±6.66	56.62±7.84	51.72±9.82	<0.001	−0.159	0.004	−0.148	0.013	
	
CI	0.47±2.14	−0.74±2.39	−1.79±3.07	<0.001	−0.137	0.012	−0.135	0.024	
*Adjusted for variables such as age, sex, liver disease aetiology, alanine aminotransferase, aspartate aminotransferase, albumin, total bilirubin, haemoglobin and platelet count. aIncluding non-cirrhosis. bExcluding non-cirrhosis. CI: confidence interval, CTP: Child–Turcotte–Pugh, MA: maximum amplitude, MELD: model for endstage liver disease

TEG parameters and blood loss during liver resection

Of the 344 patients, 313 underwent liver resection. The surgery complexity distribution revealed no significant differences among patients in the non-cirrhotic group or among those with cirrhosis of different severities according to the CTP score classes (P = 0.490) [Table 1]. In contrast, statistically significant differences were observed in surgery complexity distribution among patients in the non-cirrhotic group and those with cirrhosis of different severities according to the MELD score classes (P = 0.045) [Table 1].

In the partial correlation analyses, the following variables in Table 1 were included in the adjustment: age, sex, liver disease aetiology, ALT, AST, albumin, total bilirubin, haemoglobin, platelet count and liver resection complexity. After multivariable adjustment, all the TEG parameters except R-times obtained before surgery, measured by either CTP or MELD scores, were not correlated with blood loss during surgery in patients with chronic viral liver diseases (including non-cirrhosis) (all P > 0.05) [Table 4]. The correlation between R-times and blood loss was weak (r < 0.2) [Table 4]. The results were not significantly different after excluding non-cirrhotic patients [Table 4].

Table 4 Association between thromboelastography parameters and blood loss (coefficients with 95% CI).

Parameter	Blood loss correlation coefficient*a	P	Blood loss correlation coefficient*b	P	Blood loss correlation coefficient†a	P	Blood loss correlation coefficient†b	P	
R-time (min)	0.128	0.027	0.147	0.019	0.130	0.024	0.154	0.014	
K-time (min)	0.059	0.312	0.052	0.411	0.064	0.267	0.059	0.353	
α-angle (°)	−0.072	0.213	−0.072	0.257	−0.078	0.180	−0.081	0.202	
MA (mm)	−0.026	0.651	−0.003	0.966	−0.032	0.586	−0.010	0.873	
CI	0.038	0.517	0.062	0.331	0.034	0.562	0.055	0.382	
*Liver severity according to CTP scores. †Liver severity according to MELD scores. aIncluding non-cirrhosis. bExcluding non-cirrhosis. CI: confidence interval, CTP: Child–Turcotte–Pugh, MA: maximum amplitude, MELD: model for endstage liver disease

DISCUSSION

The present study demonstrated that TEG parameters (except R-times) significantly trended towards longer K-times, smaller α-angles and lower MA with increased liver disease severity, regardless of whether they were determined by CTP or MELD scores. Though after multivariable adjustment, TEG parameters were not correlated with liver disease severity or cirrhosis according to the CTP scores, and they were still correlated to liver disease severity or cirrhosis according to the MELD scores. R-times before surgery were associated with blood loss during liver resection according to the CTP or MELD scores, though the correlation between R-times and blood loss was weak.

Haemostasis in chronic liver diseases is complex. Procoagulant and anticoagulant factors decrease in parallel, accompanied by platelet dysfunction and a decrease in fibrinolytic factors.[19] Consequently, it is thought that haemostasis in liver disease is rebalanced with an increased risk for both thrombosis and bleeding, and therefore, conventional coagulation tests such as PT, APTT and INR are not suitable.[142021] Previous studies demonstrated that PT and related tests do not truly represent a balance of coagulation in vivo and are inadequate for assessing the risk of haemorrhage or thrombosis in patients with liver disease.[522] In contrast, TEG is considered a global test for haemostasis. A previous study suggested that in acute liver injury or acute liver failure, the R-time strongly correlated with APTT and weakly correlated with INR.[23] In contrast, our present results found that the TEG parameters were weakly correlated with PT, APTT and INR [Supplementary Table 2, Appendix]. TEG-guided haemostasis monitoring has been shown to be effective during surgery.[10] Furthermore, TEG also demonstrated potential as a guide for blood product transfusion in liver transplant surgery or before invasive procedures performed in patients with liver diseases.[1112] The present study demonstrated that TEG parameters measured before surgery were not related to blood product transfusion during surgery [Supplementary Table 3, Appendix]. Therefore, in order to guide blood product infusion, TEG should be measured during surgery.[23] However, although TEG-guided infusion decreased the use of blood products, it did not improve morbidity or mortality.[242526]

The correlation between TEG parameters and cirrhosis severity has also been explored. A study involving 51 patients with cirrhosis suggested that TEG could be used to measure haemostasis.[27] Another study involving 164 cirrhotic patients suggested that hypocoagulable TEG parameters were associated with advanced stages of cirrhosis.[13] Nevertheless, the number of included patients in these studies was small, and patients with primary biliary cirrhosis in addition to viral liver disease were included.[1327] TEG results showed that patients with primary biliary cirrhosis were relatively hypercoagulable in comparison to those with non-cholestatic liver diseases.[28] Our study demonstrated that hypocoagulable TEG parameters were correlated with increased chronic viral liver disease severity. Of note, after adjustment for multiple factors, the correlation between TEG parameters and chronic viral liver diseases or cirrhosis was not significant according to the CTP scores, and the MELD scores still revealed a weak correlation. The results of our study were consistent with a previous study, which also demonstrated a weak correlation between TEG parameters and liver cirrhosis.[14]

Previous studies have also attempted to predict bleeding in chronic liver diseases with TEG measurements. However, the results remain controversial. A study involving 20 patients suggested that hypocoagulability in cirrhotic patients determined by TEG measurements might be associated with early rebleeding.[29] Another study involving 60 cirrhotic patients suggested that TEG measurements were not related to bleeding after invasive procedures.[11] The present study, which involved more than 300 patients who underwent liver resection, showed that R-times obtained before liver resection were weakly associated with blood loss during the procedure, after making adjustments for liver disease severity and resection complexity.

The results of our study, which included more than 300 patients, suggests the potential use of TEG analysis to evaluate haemostasis in chronic viral liver disease and liver cirrhosis patients or to predict blood loss during surgery. Haemostasis in patients with liver disease is complicated, and various studies have attempted to investigate haemostasis by analysis of TEG parameters. Some results, including ours, indicated that patients with liver cirrhosis showed hypocoagulability, whereas other studies demonstrated a rebalanced haemostasis equilibrium in liver cirrhosis, with a prothrombotic tendency.[132730] Moreover, the risk of bleeding in patients with stable cirrhosis is low. A previous report showed a similar coagulation profile regardless of underlying cirrhosis after liver resection, and many cirrhotic patients also showed hypercoagulability.[31] R-times before surgery were weakly associated with blood loss during liver resection in the present study. Therefore, the use of TEG for assessing haemostasis and predicting blood loss in chronic viral liver diseases or liver cirrhosis remains unclear and should be explored in future high-quality studies involving large number of patients.

Our study had several limitations. First, it was a retrospective, single-centre, cross-sectional study and TEG measurements were assessed only once for each patient. Prospective studies involving serial TEG measurements might explain the correlation between TEG parameters and chronic liver disease severity that we observed. Second, the bleeding and thrombotic events were deficient, and the association between hypocoagulability and bleeding or thrombosis could not be analysed. Third, only patients with well-decompensated liver disease were considered for liver resection and underwent TEG measurement. Therefore, the results might not reflect applicability of TEG for patients with more advanced disease.

In conclusion, our study demonstrated that TEG parameters were significantly associated with advanced stages of chronic viral liver disease, though the correlations were weak. R-times before surgery were weakly associated with blood loss during liver resection. Our results suggest the potential use of TEG analysis for the assessment of haemostasis and prediction of blood loss during surgery in patients with chronic viral liver disease, though the results should be further explored in high-quality studies with a larger number of patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Supplemental digital content

Appendix at http://links.lww.com/SGMJ/A128

Acknowledgement

The authors would like to extend their gratitude to Ms. Xiaoqing Yu for helping with the data collection and all surgeons in the Department of Hepatobiliary Surgery at the First Affiliated Hospital of Xi’an Jiaotong University.

APPENDIX

Supplementary Table 1 Classification for the complexity of liver resections.

Complexity	Resection	
Low complexity	• Peripheral wedge resection, <3cm	
	• Left lateral sectionectomy	
Medium complexity	• Left hepatectomy without caudate	
	• Right hepatectomy	
	• Right posterior sectionectomy	
	• Left hepatectomy with caudate	
	• Isolated caudate resection	
	• Right trisectionectomy	
High complexity	• Right anterior sectionectomy	
	• Right hepatectomy with caudate resection	
	• Right hepatectomy with hepaticojejunostomy	
	• Anatomic middle hepatectomy	
	• Right trisectionectomy with caudate resection	
	• Left trisectionectomy without caudate resection	
	• Right trisectionectomy with hepaticojejunostomy	
	• Left trisectionectomy with caudate resection	
	• Right hepatectomy with portal vein reconstruction (main to left)	
	• Right trisectionectomy with portal vein reconstruction (main to left)
• Right hepatectomy with IVC reconstruction	

Supplementary Table 2 The correlation of TEG parameters with PT, APTT, INR and PLT in 292 cirrhotic patients (coefficients* with P value).

 Parameter	PT	APPT	INR	PLT	
R-time (min)	0.056 (0.353)	0.182 (0.002)	0.044 (0.463)	—0.170(0.004)	
K-time (min)	0.232 (<0.001)	0.009 (0.877)	0.246 (<0.001)	—0.504 (<0.001)	
α-angle (°)	—0.230 (<0.001)	—0.032 (0.588)	0.235 (<0.001)	0.565 (<0.001)	
R-time (min)	—0.293 (<0.001)	—0.094 (0.117)	0.294 (<0.001)	0.716 (<0.001)	
CI	—0.257 (<0.001)	—0.124 (0.037)	0.261 (<0.001)	0.582 (<0.001)	
*Adjust for the variables such as age, sex, liver disease aetiology, alanine aminotransferase (ALT), aspartate aminotransferase (AST), albumin, total bilirubin, haemoglobin and platelet count, and severity of cirrhosis according to Child–Turcotte–Pugh (CTP) scores. APTT: activated partial thromboplastin time, CI: confidence interval, INR: international normalised ratio, PLT: prothrombin time, PT: platelet count, TEG: thromboelastography

Supplementary Table 3 Association between TEG parameters and blood transfusion adjust for liver resection complexity in 264 cirrhotic patients (coefficients with P value).

 Parameter	Red blood cell	The plasma	Cryoprecipitate	Blood platelet	
R-time (min)	—0.18 (0.075)	0.045 (0.427)	—0.024 (0.677)	—0.012 (0.828)	
K-time (min)	—0.074 (0.200)	0.026 (0.650)	0.033 (0.558)	0.067 (0.236)	
α-angle (degree)	0.087 (0.133)	—0.014 (0.802)	—0.032 (0.576)	—0.068 (0.229)	
R-time (min)	0.057 (0.322)	—0.009 (0.874)	—0.063 (0.266)	—0.103 (0.070)	
CI	0.160 (0.005)	0.065 (0.250)	0.023 (0.686)	—0.072 (0.204)	
CI: confidence interval, TEG: thromboelastography
==== Refs
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