Table 3 Univariate analysis of risk factors for postoperative DVT

Age (≥ 65 years vs < 65 years)

36/2

300/230

Sex (women vs men)

28/10

306/224

BMI (≥ 25 vs < 25)

12/26

205/325

Hypertension (yes vs no)

22/16

207/323

Diabetes (yes vs no)

5/33

56/474

Cardiovascular disease (yes vs no)

6/32

62/468

Cerebral infarction (yes vs no)

9/29

79/451

Tumor (yes vs no)

6/32

20/510

Anticoagulation (yes vs no)

3/35

39/491

Triglyceride (mmol/L)

1.0(0.7, 1.4)

1.1(0.8, 1.5)

Cholesterol (mmol/L)

4.3 ± 1.0

4.8 ± 10.2

Apolipoprotein A (g/L)

1.1(0.9, 1.2)

1.0(0.9, 1.1)

Apolipoprotein B (g/L)

0.7(0.6, 0.9)

0.8(0.7, 0.9)

Preoperative hemoglobin (g/L)

129.0(117.3, 137.3)

128.0(117.0, 137.0)

Preoperative RBC (10^12/L)

4.2(3.9, 4.5)

4.2(3.9, 4.6)

Preoperative HCT (L/L)

37.6 ± 4.2

39.4 ± 10.0

Preoperative platelet (10^9/L)

196.0(155.5, 241.5)

190.0(155.0, 236.0)

Preoperative APTT (sec)

27.6(26.1, 28.3)

27.3(25.7, 29.1)

Preoperative PT (sec)

11.6(11.0, 12.1)

11.3(10.8, 12.0)

Preoperative TT (sec)

17.4(16.6, 18.8)

17.6(16.9, 18.5)

Preoperative fibrinogen (g/L)

3.3(2.7, 3.9)

3.0(2.6, 3.8)

Preoperative D-dimer (mg/L)

2.0(1.1, 6.7)

0.8(0.4, 1.9)

Duration of surgery (≥ 90 min vs < 90 min)

24/14

353/177

Intraoperative bleeding (ml)

150.0(100.0, 300.0)

200.0(100.0,250.0)

Postoperative bedrest time (day)

2.0(1.0, 3.0)

2.0(1.0, 2.0)

Postoperative drainage volume (ml)

140.0(50.0, 240.0)

120.0(60.0, 210.0)

Postoperative hemoglobin (g/L)

101.5(93.0, 111.3)

105.0(94.0,116.0)

Postoperative RBC (10^12/L)

3.4(3.1, 3.6)

3.4(3.1, 3.8)

Postoperative HCT (L/L)

30.7 ± 4.6

31.1 ± 5.0

Postoperative platelet (10^9/L)

202.0(182.0, 240.0)

178.0(142.0, 225.0)

Postoperative PT (sec)

12.3(11.4, 12.7)

11.6(10.9, 12.3)

Postoperative APTT (sec)

28.8(27.2, 32.7)

28.7(26.2,32.3)

Postoperative fibrinogen (g/L)

5.3 ± 1.1

5.1 ± 1.1

Postoperative TT (sec)

16.0(15.6, 16.5)

16.1(15.6, 16.7)

Postoperative D-dimer (mg/L)

2.2(1.5, 3.3)

1.9(1.3, 2.6)