Establishment of a risk assessment score for deep vein thrombosis after artificial liver support system treatment

Table 1 Comparison of demographic and clinical characteristics for deep venous thrombosis after artificial liver support system in Stage I

Parameters	DVT (n = 12)	No-DVT (n = 220)	Statistics	P value
Gender, n (%)
Man	7 (58.3)	165 (75)	1.649	0.306
Woman	5 (41.7)	55 (25)
Age (yrs), n (%)
< 40	2 (18.2)	51 (28.7)	7.17	0.027
< 60, ≥ 40	4 (36.4)	101 (56.7)
≥ 60	5 (45.5)	26 (14.6)
Mean arterial pressure (mmHg), mean ± SD	83.45 ± 14.47	84.11 ± 13.26	0.768	0.707
Fasting plasma glucose (mmol/L), mean ± SD	5.43 ± 1.51	5.41 ± 1.65	0.332	0.542
Smoke, n (%)
No	7 (58.3)	142 (64.5)	0.197	0.759
Yes	5 (41.7)	78 (35.5)
Catheterization mode, n (%)
Jugular vein	0 (0)	72 (30)	5.09	0.022
Femoral vein	12 (100)	168 (70)
Times of successful catheterization, n (%)
One	3 (25)	151 (71.9)	16.669	0
Two	4 (33.3)	41 (19.5)
Three and more	5 (21.7)	18 (8.6)
Heparin therapy, n (%)
No	3 (25)	56 (25.5)	0.01	0.971
Yes	9 (75)	164 (74.5)
Procoagulant therapy, n (%)
No	8 (67.7)	164 (74.5)	0.368	0.513
Yes	4 (33.3)	56 (125.5)
Etiology, n (%)
Virus hepatitis	9 (75)	133 (60.5)	1.028	0.795
Drug injury	1 (8.3)	29 (13.2)
Autoimmune liver disease	1 (8.3)	24 (11.8)
Others	1 (8.3)	32 (14.5)
ALSS times, n (%)
< 3	3 (25)	61 (27.7)	7.344	0.025
≥ 3, < 5	5 (21.7)	139 (63.2)
≥ 5	4 (33.3)	20 (9.1)
Activity status, n (%)
Free activities	0 (0)	23 (10.5)	10.773	0.013
Less than 4 h/d	2 (16.7)	89 (40.5)
Less than 1 h/d	4 (33.3)	74 (33.6)
Strict bed rest	6 (50.0)	32 (15.5)
Ascites status, n (%)
No	3 (25)	67 (28.1)	0.923	0.82
Mild	4 (33.3)	79 (37.6)
Moderate	3 (25)	56 (25.7)
Severe	2 (16.7)	19 (8.6)
Bleeding, n (%)
No	8 (67.7)	153 (69.5)	0.436	0.833
Yes	4 (33.3)	67 (30.5)
Hepatic encephalopathy, n (%)
No	6 (54.5)	148 (67.3)	1.933	0.385
I-II	4 (33.3)	55 (25.0)
III-IV	2 (17.5)	17 (7.7)
Infection, n (%)
No	4 (33.3)	144 (65.5)	5.083	0.031
Yes	8 (67.7)	76 (34.5)
Complicated by other serious diseases, n (%)
No	8 (67.7)	174 (79.1)	1.039	0.294
Yes	4 (33.3)	46 (20.9)
Body mass index (kg/m2), n (%)
< 23	2 (20.0)	77 (35)	2.262	0.332
≥ 23, < 25	4(40.0)	97 (44.1)
≥ 25	4 (40.0)	46 (20.9)
Platelet count (109/L), n (%)
< 100	3 (25)	99 (45)	2.258	0.277
≥ 100, < 300	8 (66.7)	95 (43.2)
≥ 300	1 (8.3)	16 (11.8)
Total bilirubin (μmol/L), mean ± SD	234.45 ± 155.12	231.65 ± 132.86	1.476	0.583
Alanine aminotransferase (U/L), mean ± SD	256.82 ± 243.455	294.65 ± 341.36	1.20·	0.578
D-dimer (ng/mL), n (%)
< 200	1 (8.3)	88 (40)	12.232	0.002
≥ 200, < 500	3 (25.9)	82 (37.3)
≥ 500	8 (66.7)	50 (22.7)
Fibrinogen (g/L), mean ± SD	1.25 ± 0.43	1.33 ± 1.12	2.554	0.212
International normalized ratio, n (%)
< 1.5	0 (0)	0 (0)	0.215	0.767
≥ 1.5, < 2	6 (54.5)	125 (56.8)
≥ 2	6 (45.5)	85 (43.2)

DVT: Deep venous thrombosis; ALSS: Artificial liver support system.

Table 2 Logistic regression analysis of influencing factors of deep venous thrombosis after artificial liver support system

Parameters	β	Wald χ2	OR	95%CI	P value
Age (yrs)	0.454	5.776	1.734	1.034-2.543	0.01
< 40	1
< 60, ≥ 40	0.034	2.765	1.114	0.324-3.654	0.95
≥ 60	3.354	8.234	1.886	1.154-4.853	0.005
Catheterization mode
Jugular vein	1
Femoral vein	0.068	0.976	0.645	0.550-1.655	0.121
ALSS times	1.63	1.424		0.257-1.667	0.223
< 3	1
≥ 3, < 5	0.354	0.564	0.454	0.416-2.534	0.531
≥ 5	0.243	0.486	1.321	1.013-6.534	0.615
Times of successful catheterization
One	1
Two	0.672	1.534	0.674	0.056-1.132	0.242
Three and more	1.246	6.435	1.667	1.005-3.235	0.005
Activity status
Free activities	1
Less than 4 h/d	0.54	1.004	1.028	0.062-1.002	0.972
Less than 1 h/d	0.764	0.172	1.565	0.999-1.504	0.128
Strict bed rest	1.547	11.074	3.049	1.744-8.414	< 0.001
D-dimer (ng/mL)
< 200	1
≥ 200, < 500	1.322	1.653	1.674	1.056-2.232	0.064
≥ 500	2.115	12.231	5.532	1.404-12.133	< 0.001
Infection
No	1
Yes	2.431	16.236	2.426	1.003-89.342	0.008

OR: Odds ratio; CI: Confidence interval; ALSS: Artificial liver support system.

Table 3 Establishment of risk assessment score for deep venous thrombosis after artificial liver support system

Indicators	Score
D-dimer	3
Infection	2
Strict bed rest	2
Age (≥ 60 yrs)	2
Times of successful catheterization (≥ 3)	1

Total points: 10 points, ≥ 5 points for high risk, ≥ 3, and < 5 points for moderate risk, < 3 points for low risk.

Table 4 Comparison of demographic and clinical characteristics for deep venous thrombosis after artificial liver support system stage II, n (%)

Parameters	DVT (n = 14)	No-DVT (n = 199)	Statistics	P value
Gender
Man	9 (64.3)	165 (82.9)	3.035	0.082
Woman	5 (35.7)	34 (17.1)
Age (yrs)
< 40	2 (16.7)	51 (25.6)	11.004	0.004
< 60, ≥ 40	2 (16.7)	101 (50.8)
≥ 60	8 (66.7)	47 (23.6)
Catheterization mode
Jugular vein	2 (14.3)	51 (25.6)	0.903	0.343
Femoral vein	12 (85.7)	148 (74.4)
Times of successful catheterization
One	3 (21.4)	120 (60.3)	13.742	0.001
Two	4 (28.6)	51 (25.6)
Three and more	7 (50.0)	28 (14.1)
ALSS times
< 3	4 (28.6)	61 (30.7)	9.207	0.01
≥ 3, < 5	5 (35.7)	119 (50.8)
≥ 5	5 (35.7)	19 (9.5)
Activity status
Free activities	0 (0)	23 (11.6)	11.761	0.008
Less than 4 h/d	4 (28.6)	69 (34.7)
Less than 1 h/d	4 (28.6)	84 (42.6)
Strict bed rest	6 (42.9)	23 (11.6)
Infection
No	4 (28.6)	114 (57.6)	4.365	0.037
Yes	10 (71.4)	85 (42.4)
D-dimer (ng/mL)
< 200	1 (7.1)	65 (32.7)	14.84	0.001
≥ 200, < 500	4 (28.6)	94 (47.2)
≥ 500	9 (64.3)	40 (20.1)

DVT: Deep venous thrombosis; ALSS: Artificial liver support system.